Characteristics of Amorphophallus campanulatus Modified Starch as Novel Adsorbent for Nickel and Cadmium Removal from Aqueous Solution

NASA Astrophysics Data System (ADS)

Lestari, A. Y. D.; Dewi, L. K.

2018-05-01

Novel adsorbents are succesfully manufactured from Amorphophalluscampanulatus (Porang or Suweg or Elephant Foot Yam or Foot Yam) starch. The experiment focused on modifiying the starch with citric acid and detailing those morphologies and chemical bonds. Analysis with FTIR and SEM showed that PTM (modified porous porang starch) sample is the best adsorbent which has most stable of chemical bonding and also has the most pores that influence an adsorption phenomena. Isotherm adsorption analysis showed that the adsorption mechanism of Cd and Ni ions onto the suface of PB, PT and PTM followed the Temkin and Langmuir isotherm adsorption. Adsorption ability of PTM is the best than the other PB and PT which can adsorps 256,23 mg Cd/g PTM and 87,45 mg Ni/g PTM in 500 ppm synthetic aqueous solution

Electron beam technology for modifying the functional properties of maize starch

NASA Astrophysics Data System (ADS)

Nemţanu, M. R.; Minea, R.; Kahraman, K.; Koksel, H.; Ng, P. K. W.; Popescu, M. I.; Mitru, E.

2007-09-01

Maize starch is a versatile biopolymer with a wide field of applications (e.g. foods, pharmaceutical products, adhesives, etc.). Nowadays there is a continuous and intensive search for new methods and techniques to modify its functional properties due to the fact that native form of starch may exhibit some disadvantages in certain applications. Radiation technology is frequently used to change the properties of different polymeric materials. Thus, the goal of the work is to discuss the application of accelerated electron beams on maize starch in the view of changing some of its functional properties. Maize starch has been irradiated with doses up to 52.15 kGy by using electron beam technology and the modifications of differential scanning calorimetry (DSC) and pasting characteristics, paste clarity, freezing and thawing stability as well as colorimetric characteristics have been investigated. The results of the study revealed that the measured properties can be modified by electron beam treatment and, therefore, this method can be an efficient and ecological alternative to obtain modified maize starch.

Comparative Emulsifying Properties of Octenyl Succinic Anhydride (OSA)-Modified Starch: Granular Form vs Dissolved State

PubMed Central

Marefati, Ali; Gutiérrez, Gemma; Wahlgren, Marie; Rayner, Marilyn

2016-01-01

The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable. PMID:27479315

Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch

NASA Astrophysics Data System (ADS)

Teixeira, Bruna S.; Garcia, Rafael H. L.; Takinami, Patricia Y. I.; del Mastro, Nelida L.

2018-01-01

The objective of this work was to evaluate the effect of irradiation treatment on physicochemical properties of three natural polymers, i.e. native potato and corn starches and a typical Brazilian product, cassava starch modified through fermentation -sour cassava- and also to prepare composite hydrocolloid films based on them. Starches were irradiated in a 60Co irradiation chamber in doses up to 15 kGy, dose rate about 1 kGy/h. Differences were found in granule size distribution upon irradiation, mainly for corn and cassava starch but radiation did not cause significant changes in granule morphology. The viscosity of the potato, corn and cassava starches hydrogels decreased as a function of absorbed dose. Comparing non-irradiated and irradiated starches, changes in the Fourier transform infrared (FTIR) spectra in the 2000-1500 cm-1 region for potato and corn starches were observed but not for the cassava starch. Maximum rupture force of the starch-based films was affected differently for each starch type; color analysis showed that doses of 15 kGy promoted a slight rise in the parameter b* (yellow color) while the parameter L* (lightness) was not significantly affected; X-ray diffraction patterns remained almost unchanged by irradiation.

Optimization and characterization of high pressure homogenization produced chemically modified starch nanoparticles.

PubMed

Ding, Yongbo; Kan, Jianquan

2017-12-01

Chemically modified starch (RS4) nanoparticles were synthesized through homogenization and water-in-oil mini-emulsion cross-linking. Homogenization was optimized with regard to z-average diameter by using a three-factor-three-level Box-Behnken design. Homogenization pressure (X 1 ), oil/water ratio (X 2 ), and surfactant (X 3 ) were selected as independent variables, whereas z-average diameter was considered as a dependent variable. The following optimum preparation conditions were obtained to achieve the minimum average size of these nanoparticles: 50 MPa homogenization pressure, 10:1 oil/water ratio, and 2 g surfactant amount, when the predicted z-average diameter was 303.6 nm. The physicochemical properties of these nanoparticles were also determined. Dynamic light scattering experiments revealed that RS4 nanoparticles measuring a PdI of 0.380 and an average size of approximately 300 nm, which was very close to the predicted z-average diameter (303.6 nm). The absolute value of zeta potential of RS4 nanoparticles (39.7 mV) was higher than RS4 (32.4 mV), with strengthened swelling power. X-ray diffraction results revealed that homogenization induced a disruption in crystalline structure of RS4 nanoparticles led to amorphous or low-crystallinity. Results of stability analysis showed that RS4 nanosuspensions (particle size) had good stability at 30 °C over 24 h.

Green natural rubber-g-modified starch for controlling urea release.

PubMed

Riyajan, Sa-Ad; Sasithornsonti, Yodsathorn; Phinyocheep, Pranee

2012-06-05

The hydrophilicity of natural rubber (NR) was improved by grafting with modified cassava starch (ST) (NR-g-ST) by using potassium persulfate (K2S2O8) as a catalyst. The modified ST was added to NR latex in the presence of Terric16A16 as a non-ionic surfactant at 60 °C for 3 h and cast film on a glass plate to obtain NR-g-ST. The chemical structure of NR-g-ST was confirmed by FTIR. The swelling ratio of NR-g-ST was investigated in water and results showed that the swelling ratio of the modified NR decreased as function of ST. In addition, the tensile strength of the modified NR in the presence of modified ST at 50 phr was the highest value. Also, the thermal stability modified NR-g-ST was higher than of NR/ST blend confirmed by TGA. Finally, the NR-g-ST was used a polymer membrane for controlling urea fertilizer and it easily degraded in soil. This product with good controlled-release and water-retention could be especially useful in agricultural and horticultural applications. Published by Elsevier Ltd.

Enzyme-modified starch as an oil delivery system for bake-only chicken nuggets.

PubMed

Purcell, Sarah; Wang, Ya-Jane; Seo, Han-Seok

2014-05-01

This study investigated the effects of enzyme modification on starch as an effective oil delivery system for bake-only chicken nuggets. Various native starches were hydrolyzed by amyloglucosidase to a hydrolysis degree of 20% to 25% and plated with 50% (w/w, starch dry basis) with canola oil to create a starch-oil matrix. This matrix was then blended into a dry ingredient blend for batter and breader components. Nuggets were prepared by coated with predust, hydrated batter, and breader, and the coated nuggets were steam-baked until fully cooked and then frozen until texture and sensory analyses. The enzyme-modified starches showed a significant decrease in pasting viscosities for all starch types. For textural properties of nuggets, no clear relationship was found between peak force and starch source or amylose content. Sensory attributes related to fried foods (for example, crispness and mouth-coating) did not significantly differ between bake-only nuggets formulated using the enzyme-modified starches and the partially fried and baked ones. The present findings suggest that enzyme-modified starches can deliver sufficient quantity of oil to create sensory attributes similar to those of partially fried chicken nuggets. Further study is needed to optimize the coating formulation of bake-only chicken nugget to become close to the fried one in sensory aspects. The food industry has become increasingly focused on healthier items. Frying imparts several critical and desirable product functionalities, such as developing texture and color, and providing mouth-feel and flavor. The food industry has yet to duplicate all of the unique characteristics of fried chicken nuggets with a baking process. This study investigated the application of enzyme-modified starch as an oil delivery system in bake-only chicken nugget formulation in attempts to provide characteristics of fried items. This information is useful to improve the nutritional value of fried food by eliminating the

21 CFR 172.892 - Food starch-modified.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Food starch-modified. 172.892 Section 172.892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION...

21 CFR 172.892 - Food starch-modified.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Food starch-modified. 172.892 Section 172.892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION...

21 CFR 172.892 - Food starch-modified.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Food starch-modified. 172.892 Section 172.892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.892 Food...

Starch--value addition by modification.

PubMed

Tharanathan, Rudrapatnam N

2005-01-01

Starch is one of the most important but flexible food ingredients possessing value added attributes for innumerable industrial applications. Its various chemically modified derivatives offer a great scope of high technological value in both food and non-food industries. Modified starches are designed to overcome one or more of the shortcomings, such as loss of viscosity and thickening power upon cooking and storage, particularly at low pH, retrogradation characteristics, syneresis, etc., of native starches. Oxidation, esterification, hydroxyalkylation, dextrinization, and cross-linking are some of the modifications commonly employed to prepare starch derivatives. In a way, starch modification provides desirable functional attributes as well as offering economic alternative to other hydrocolloid ingredients, such as gums and mucilages, which are unreliable in quality and availability. Resistant starch, a highly retrograded starch fractionformed upon food processing, is another useful starch derivative. It exhibits the beneficial physiological effects of therapeutic and nutritional values akin to dietary fiber. There awaits considerable opportunity for future developments, especially for tailor-made starch derivatives with multiple modifications and with the desired functional and nutritional properties, although the problem of obtaining legislative approval for the use of novel starch derivatives in processed food formulations is still under debate. Nevertheless, it can be predicted that new ventures in starch modifications and their diverse applications will continue to be of great interest in applied research.

Modified starch containing liquid fuel slurry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Metzger, G.W.

1978-04-04

A substantially water-free, high solids content, stably dispersed combustible fuel slurry is provided, with a method of preparing the slurry. The slurry contains a minor amount of a solid particulate carbonaceous material such as powdered coal, with substantially the entire balance of the slurry being comprised of a liquid hydrocarbon fuel, particularly a heavy fuel oil. In extremely minor amounts are anionic surfactants, particularly soaps, and a stabilizing amount of a starch modified with an anionic polymer.

Effect of alkali and oxidative treatments on the physicochemical, pasting, thermal and morphological properties of corn starch.

PubMed

Spier, Franciela; Zavareze, Elessandra da Rosa; Marques e Silva, Ricardo; Elias, Moacir Cardoso; Dias, Alvaro Renato Guerra

2013-07-01

Few studies on starch modifications using different chemical agents are available in the literature, and no reports were found on the combined effect of oxidation and alkaline treatment of corn starch. Thus this work evaluated the physicochemical, pasting, morphological, cystallinity and thermal properties of chemically modified corn starch, after either the isolated or combined action of alkaline (sodium hydroxide) and oxidative (sodium hypochlorite) treatments. The highest values for the sum of carbonyl and carboxyl and enzymatic hydrolysis occurred in starches submitted to oxidative treatment at high active chlorine concentrations. The alkali treatment in isolation modified the pasting properties, reduced the paste temperature and increased the peak viscosity, breakdown, final viscosity and setback of starches. Starch modified by the action of sodium hypochlorite and hydroxide in combination presented more severe damage on granule surfaces. The results show that corn starch modified by the combined action of oxidative and alkaline treatments should be studied more, especially at the concentration limit of sodium hydroxide where gelatinization occurs. Under these conditions the effect of oxidation can be more intense and thus allow the production of starches with different properties and an increase in their industrial applications. © 2013 Society of Chemical Industry.

Evaluation of the material and tablet formation properties of modified forms of Dioscorea starches.

PubMed

Odeku, Oluwatoyin A; Picker-Freyer, Katharina M

2009-11-01

Starches obtained from four different Dioscorea species-namely, White yam (Dioscorea rotundata), Bitter yam (Dioscorea dumetorum), Chinese yam (Dioscorea oppositifolia), and Water yam (Dioscorea alata)-were modified by cross-linking, hydroxypropylation, and dual modification-cross-linking followed by hydroxypropylation. The physicochemical, material, and tablet properties of the modified starches were investigated with the aim of understanding their properties to determine their potential use for different applications. The tablet formation properties were assessed using 3D modeling, the Heckel equation, and force-displacement profiles. The analyzed tablet properties were elastic recovery, compactibility, and disintegration. The result indicates that the modifications generally increased the swelling power for all the starches in the rank order hydroxypropyl > hydroxypropylated cross-linked > cross-linked (CL) while the solubility did not show a clear-cut pattern. This indicates that hydroxypropylation generally showed the strongest effects on swelling. Furthermore, hydroxypropylation improved the hot water swelling of the CL starches. The modifications did not cause any detectable morphological change in the starch granules shape or size although slight rupture was observed in some granules. CL starch had the lowest water sorption capacity and hydroxypropylation increased the sorption capacity of the CL starches. The material property results indicate that hydroxypropylation and cross-linking did not significantly improve the flowability and compressibility but improved bonding, which resulted in an increased compaction and higher tablet crushing force even though they all disintegrated rapidly. Thus, the modified Dioscorea starches showed potentials for development as new excipients in solid dosage form design, and they could be useful as disintegrants or for Soft tableting.

Dynamic high-pressure microfluidization assisting octenyl succinic anhydride modification of rice starch.

PubMed

Li, Yu-Ting; Wang, Ri-Si; Liang, Rui-Hong; Chen, Jun; He, Xiao-Hong; Chen, Rui-Yun; Liu, Wei; Liu, Cheng-Mei

2018-08-01

Octenyl succinic anhydride (OSA) modified starch is widely used in food industries. In this study, rice starch (RS) was pretreated by dynamic high-pressure microfluidization (DHPM) and subsequently modified by OSA. The influence of DHPM on OSA modification of rice starch was investigated. Results showed that DHPM pretreatment enhanced the degree of substitution by changing the morphology and crystallinity of rice starch. Compared with the rice starch modified by OSA without DHPM pretreatment (OSA-RS), the DHPM-pretreated OSA starch (DHPM-OSA-RS) presented higher peak viscosity and lower pasting temperature. DHPM-OSA-RS also exhibited better emulsifying activity and emulsion stability. This study suggested that DHPM will provide an opportunity to change the physicochemical properties of starch, with the resulting starch being more suitable for chemical modification. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preparation and physico-chemical properties of hydrogels from carboxymethyl cassava starch crosslinked with citric acid

NASA Astrophysics Data System (ADS)

Boonkham, Sasikan; Sangseethong, Kunruedee; Chatakanon, Pathama; Niamnuy, Chalida; Nakasaki, Kiyohiko; Sriroth, Klanarong

2014-06-01

Recently, environmentally friendly hydrogels prepared from renewable bio-based resources have drawn significant attention from both industrial and academic sectors. In this study, chemically crosslinked hydrogels have been developed from cassava starch which is a bio-based polymer using a non-toxic citric acid as a crosslinking agent. Cassava starch was first modified by carboxymethylation to improve its water absorbency property. The carboxymethyl cassava starch (CMCS) obtained was then crosslinked with citric acid at different concentrations and reaction times. The gel fraction of hydrogels increased progressively with increasing citric acid concentration. Free swelling capacity of hydrogels in de-ionized water, saline solution and buffers at various pHs as well as absorption under load were investigated. The results revealed that swelling behavior and mechanical characteristic of hydrogels depended on the citric acid concentration used in reaction. Increasing citric acid concentration resulted in hydrogels with stronger network but lower swelling and absorption capacity. The cassava starch hydrogels developed were sensitive to ionic strength and pH of surrounding medium, showing much reduced swelling capacity in saline salt solution and acidic buffers.

Substitution of modified starch with hydrogen peroxide-modified rice bran in salad dressing formulation: physicochemical, texture, rheological and sensory properties.

PubMed

Maani, Bahareh; Alimi, Mazdak; Shokoohi, Shirin; Fazeli, Fatemeh

2017-06-01

Rice bran samples were treated under different conditions including hydrogen peroxide content (1, 4, and 7 wt%) and media pH (10.5, 11.5, and 12.5). Water holding capacity and color measurement results showed acceptable improvements compared with the untreated native bran confirmed by Fourier transform infrared analysis. Optimization of modification conditions upon characterization results suggested the introduction of 7% hydrogen peroxide at pH = 12.5. Accordingly, 1, 2 and 3 wt% of the rice bran treated under the optimized conditions, was used in salad dressing formulation; as for .3 wt% of modified starch in the formulation of blank sample, 1 wt% of treated rice bran dietary fiber was substituted. Biopolymer swelling and formation of a stable viscous gel network promoted by the chemical treatment of lignocellulosic rice bran restrict the mobility of oil droplets dispersed in the continuous phase which would consequently retard the emulsion instability phenomena. This effect was also confirmed by flow behavior and viscoelastic characterization results. Salad dressing samples containing 1 and 2 wt% treated rice bran showed acceptable physicochemical, rheological and organoleptic properties besides superior nutritional characteristics compared with the commercial modified starch traditionally used in salad dressing formulations. Despite recommended consumption of dietary fibers, addition of unprocessed lignocellulosic materials to food products usually raise negative effects in sensory, color, and texture quality. This study investigates the modification of rice bran, the byproduct of brown rice milling, to substitute modified starch traditionally used in salad dressing formulations to achieve optimum properties desirable for the final product. Optimization of modification conditions upon characterization of the formulated samples in this study would suggest new improved formulation for the commercial product. © 2016 Wiley Periodicals, Inc.

A technical feasibility study of surfactant-free drug suspensions using octenyl succinate-modified starches.

PubMed

Kuentz, Martin; Egloff, Peter; Röthlisberger, Dieter

2006-05-01

Many new drugs exhibit poor wetting behaviour and low aqueous solubility. This is particularly an issue for preclinical studies like toxicological trials, in which considerably higher doses and volumes are being administered compared to clinical studies. Preclinical vehicles typically contain high levels of surfactants that can exert biological effects. However, the biological inertness of vehicles is pivotal for the application in preclinical studies stressing the need in finding new excipients to solve formulation problems of today's drug discovery. The present study investigated the technical feasibility of surfactant-free suspensions using a new poorly soluble drug as model. It was shown that octenyl succinate-modified starches adequately wetted the drug and homogenous tasteless suspensions were obtained. The polymer xanthan gum was identified as macroscopically compatible gelling agent. Concentration effects of xanthan, drug and different modified starches were studied in a D-optimal design with respect to rheological properties. The suspensions were also tested in an analytical centrifuge using NIR transmission profiles to obtain a measure of sedimentation stability under accelerated conditions. The modified starches exhibited only little influence on the viscosity as well as on the yield point in contrast to the rheological effects of xanthan gum. This gelling agent was the main stabilising excipient as the modified starches hindered to a lesser extent sedimentation. The most stable suspensions displayed convenient flow properties. The viscosity at 100 s(-1) and 25 degrees C was in technically acceptable range of 120-140 mPa s in view of a application via gavage or a syringe in animal studies. The results demonstrated that surfactant-free drug suspensions with excellent technical performance can be obtained using octenyl succinate-modified starches. The vehicles were tasteless and based on the experience of modified starches in the food industry, the

[Effect of acetylation and oxidation on some properties of breadfruit (Artocarpus altilis) seed starch].

PubMed

Rincón, Alicia Mariela; Bou Rached, Lizet; Aragoza, Luis E; Padilla, Fanny

2007-09-01

Starch extracted from seeds of Artocarpus altilis (Breadfruit) was chemically modified by acetylation and oxidation, and its functional properties were evaluated and compared with these of native starch. Analysis of the chemical composition showed that moisture content was higher for modified starches. Ash, protein, crude fiber and amylose contents were reduced by the modifications, but did not alter the native starch granules' irregularity, oval shape and smooth surface. Acetylation produced changes in water absorption, swelling power and soluble solids, these values were higher for acetylated starch, while values for native and oxidized starches were similar. Both modifications reduced pasting temperature; oxidation reduced maximum peak viscosity but it was increased by acetylation. Hot paste viscosity was reduced by both modifications, whereas cold paste viscosity was lower in the oxidized starch and higher in the acetylated starch. Breakdown was increased by acetylation and reduced with oxidation. Setback value was reduced after acetylation, indicating it could minimize retrogradation of the starch.

Chemical composition and functional properties of native chestnut starch (Castanea sativa Mill).

PubMed

Cruz, Bruno R; Abraão, Ana S; Lemos, André M; Nunes, Fernando M

2013-04-15

Starch isolation methods can change their physico-chemical and functional characteristics hindering the establishment of a starch-food functionality relation. A simple high yield and soft isolation method was applied for chestnut (Castanea sativa Mill) starch consisting in steeping and fruit disintegration in a 25 mM sodium bisulfite solution and purification by sedimentation. Starch integrity, physico-chemical composition, morphology and functional properties were determined, being observed significant differences from previous described methods for chestnut starch isolation. The X-ray pattern was of B-type, with a degree of crystallinity ranging from 51% to 9%, dependent on the starch moisture content. The onset, peak, and conclusion gelatinization temperatures were 57.1°C, 61.9°C and 67.9°C, respectively. Total amylose content was 26.6%, and there was not found any evidence for lipid complexed amylose. Swelling power at 90°C was 19 g/g starch, and the amount of leached amylose was 78% of the total amylose content. Native chestnut starch presents a type B pasting profile similar to corn starch but with a lower gelatinization (56.1°C) and peak viscosity (79.5°C) temperatures, making native chestnut starch a potential technological alternative to corn starch, especially in application where lower processing temperatures are needed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Characterization of Modified Tapioca Starch in Atmospheric Argon Plasma under Diverse Humidity by FTIR Spectroscopy

NASA Astrophysics Data System (ADS)

Deeyai, P.; Suphantharika, M.; Wongsagonsup, R.; Dangtip, S.

2013-01-01

Tapioca is economical crop grown in Thailand and continues to be one of the major sources of starch. Nowadays, tapioca starch has been widely used in industrial applications, however the native form of starch has limited the applications. Thus scientists try to modify the properties of starch for increasing the stability of the granules, pastes to low pH, heat, and shear during the food process. We modify the tapioca starch by plasma treatment under an argon atmosphere. The degree of modification is determined by following water content in the starch granules. The tablet samples of native starch are also prepared and compared with the plasma treated starch. Before plasma treatment, the starch tablets are stored under three different relative humilities (RH) including 11%, 68%, and 78%RH, respectively. The samples are characterized using FTIR spectroscopy associated with the degree of cross-linking. The results show that the water molecules are engulfed into the starch structure in two ways, a tight bond and a weak absorption of water molecules which is represented at two wave number of 1630 cm-1 and 3272 cm-1, respectively. The degree of cross-linking can be identified from the relative intensity of these two peaks with the C—O—H peak at 993 cm-1. The results show that the degree of cross-linking increase in the plasma treated starch. The degree of cross-linking of the treated starch with high relative humidity is less than that of the treated starch with low relative humidity.

Novel FT-IR Microspectroscopic Census of Simple Starch Granules for Octenyl Succinate Ester Modification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bai, Y.; Shi, Y; Wetzel, D

Fourier transform infrared (FT-IR) microspectroscopy was used to investigate reaction homogeneity of octenyl succinic anhydride modification on waxy maize starch and detect uniformity of blends of modified and native starches. For the first time, the level and uniformity of chemical substitution on individual starch granules were analyzed by FT-IR microspectroscopy. More than 100 starch granules of each sample were analyzed one by one by FT-IR microspectroscopy. In comparison to the native starch, modified starch had two additional bands at 1723 and 1563 cm{sup -1}, indicative of ester formation in the modified starch. For the 3% modification level, the degree ofmore » substitution (DS) was low (0.019) and the distribution of the ester group was not uniform among starch granules. For the modified starch with DS of 0.073, 99% of individual starch granules had a large carbonyl band area, indicating that most granules were modified to a sufficient extent that the presence of their carbonyl ester classified them individually as being modified. However, the octenyl succinate concentration varied between granules, suggesting that the reaction was not uniform. When modified starch (DS = 0.073) was blended with native starch (3:7, w/w) to achieve a mixture with an average DS of 0.019, FT-IR microspectroscopy was able to detect heterogeneity of octenyl succinate in the blend and determine the ratio of the modified starch to the native starch granules.« less

Acetylated adipate of retrograded starch as RS 3/4 type resistant starch.

PubMed

Kapelko-Żeberska, M; Zięba, T; Spychaj, R; Gryszkin, A

2015-12-01

This study was aimed at producing acetylated adipate of retrograded starch (ADA-R) with various degrees of substitution with functional groups and at determining the effect of esterification degree on resistance and pasting characteristics of the produced preparations. Paste was prepared from native potato starch, and afterwards frozen and defrosted. After drying and disintegration, the paste was acetylated and crosslinked using various doses of reagents. An increase in the total degree of esterification of the produced ADA-R-preparation caused an increase in its resistance to the action of amyloglucosidase. Viscosity of the paste produced from ADA-R-preparation in a wide range of acetylation degrees was increasing along with increasing crosslinking of starch. The study demonstrated that acetylated adipate of retrograded starch may be classified as a preparation of RS 3/4 type resistant starch (retrograded starch/chemically-modified starch) with good texture-forming properties. The conducted modification offers the possibility of modeling the level of resistance of the produced preparation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Plasma modification of starch.

PubMed

Zhu, Fan

2017-10-01

Plasma is a medium of unbound negative and positive particles with the overall electrical charge being roughly zero. Non-thermal plasma processing is an emerging green technology with great potential to improve the quality and microbial safety of various food materials. Starch is a major component of many food products and is an important ingredient for food and other industries. There has been increasing interest in utilizing plasma to modify the functionalities of starch through interactions with reactive species. This mini-review summarises the impact of plasma on composition, chemical and granular structures, physicochemical properties, and uses of starch. Structure-function relationships of starch components as affected by plasma modifications are discussed. Effect of plasma on the properties of wheat flour, which is a typical example of starch based complex food systems, is also reviewed. Future research directions on how to better utilise plasma to improve the functionalities of starch are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

Use of enzymes to minimize the rheological dough problems caused by high levels of damaged starch in starch-gluten systems.

PubMed

Barrera, Gabriela N; León, Alberto E; Ribotta, Pablo D

2016-05-01

During wheat milling, starch granules can experience mechanical damage, producing damaged starch. High levels of damaged starch modify the physicochemical properties of wheat flour, negatively affecting the dough behavior as well as the flour quality and cookie and bread making quality. The aim of this work was to evaluate the effect of α-amylase, maltogenic amylase and amyloglucosidase on dough rheology in order to propose alternatives to reduce the issues related to high levels of damaged starch. The dough with a high level of damaged starch became more viscous and resistant to deformations as well as less elastic and extensible. The soluble fraction of the doughs influenced the rheological behavior of the systems. The α-amylase and amyloglucosidase reduced the negative effects of high damaged starch contents, improving the dough rheological properties modified by damaged starch. The rheological behavior of dough with the higher damaged-starch content was related to a more open gluten network arrangement as a result of the large size of the swollen damaged starch granules. We can conclude that the dough rheological properties of systems with high damaged starch content changed positively as a result of enzyme action, particularly α-amylase and amyloglucosidase additions, allowing the use of these amylases and mixtures of them as corrective additives. Little information was reported about amyloglucosidase activity alone or combined with α-amylase. The combinations of these two enzymes are promising to minimize the negative effects caused by high levels of damaged starch on product quality. More research needs to be done on bread quality combining these two enzymes. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Emulsion stabilizing capacity of intact starch granules modified by heat treatment or octenyl succinic anhydride.

PubMed

Timgren, Anna; Rayner, Marilyn; Dejmek, Petr; Marku, Diana; Sjöö, Malin

2013-03-01

Starch granules are an interesting stabilizer candidate for food-grade Pickering emulsions. The stabilizing capacity of seven different intact starch granules for making oil-in-water emulsions has been the topic of this screening study. The starches were from quinoa; rice; maize; waxy varieties of rice, maize, and barley; and high-amylose maize. The starches were studied in their native state, heat treated, and modified by octenyl succinic anhydride (OSA). The effect of varying the continuous phase, both with and without salt in a phosphate buffer, was also studied. Quinoa, which had the smallest granule size, had the best capacity to stabilize oil drops, especially when the granules had been hydrophobically modified by heat treatment or by OSA. The average drop diameter (d 32) in these emulsions varied from 270 to 50 μm, where decreasing drop size and less aggregation was promoted by high starch concentration and absence of salt in the system. Of all the starch varieties studied, quinoa had the best overall emulsifying capacity, and OSA modified quinoa starch in particular. Although the size of the drops was relatively large, the drops themselves were in many instances extremely stable. In the cases where the system could stabilize droplets, even when they were so large that they were visible to the naked eye, they remained stable and the measured droplet sizes after 2 years of storage were essentially unchanged from the initial droplet size. This somewhat surprising result has been attributed to the thickness of the adsorbed starch layer providing steric stabilization. The starch particle-stabilized Pickering emulsion systems studied in this work has potential practical application such as being suitable for encapsulation of ingredients in food and pharmaceutical products.

Development of modified starch technology (maltodextrin) from commercial tapioca on semi production scale using oil heater dextrinator

NASA Astrophysics Data System (ADS)

Triyono, Agus; Cecep Erwan Andriansyah, Raden; Luthfiyanti, Rohmah; Rahman, Taufik

2017-12-01

One way to improve functional starch is by modification of starch into dextrin or maltodextrin. Maltodextrin is used in the food industry as a food substitution. Development of enzymatically modified starch technology has been performed with the use of α-amylase at optimum pH of 5.5, temperature 75-85 °C, with enzyme activity of 135 KNU/g. The maltodextrin produced from commercial tapioca has the quality requirements for food according to SNI 1992. The yield of maltodextrin obtained is about 80%. The use of the optimum amount of the α-amylase enzyme is 0.07 % v/w and the substrate amount of tapioca starch is 35%. Analysis of the feasibility of modified starch with the assumption of production scale of 300 kg per day, the economic value of 10 years business, the price of starch is IDR 8,350/kg, from tapioca starch (tapioca) IDR 4,000 - IDR 4,500/kg.

[Resistant starches. Part II. Physico-chemical and technological aspects solution medico-biological problems].

PubMed

Iur'ev, V P; Gapparov, M M; Vasserman, L A; Genkina, N K

2006-01-01

This paper is a review of the recent literature data related to structure, composition and physico-chemical properties of starches as well as the special methods of processing of the starch containing raw sources producing the food products with increasing content of resistant starches. The prognosis is made about usefulness of such resistant starches for control of some metabolic disorder in human organism and for prophylactic aims.

Physicochemical Characteristics of Artificial Rice from Composite Flour: Modified Cassava Starch, Canavalia ensiformis and Dioscorea esculenta

NASA Astrophysics Data System (ADS)

Sumardiono, Siswo; Pudjihastuti, Isti; Handayani, Noer Abyor; Kusumayanti, Heny

2018-02-01

Indonesia is the third largest country on the global paddy rice production and also considered as a rice importer. Even, Indonesia has the biggest per capita consumption of paddy rice (140 kg of paddy rice per person per year). Product diversification using local commodities. Artificial rice is potential to be developed as a new value product using different types of grains. It is one of appropriate solutions for reducing imported rice rate. Artificial rice was produced using high nutrition composite flours (modified cassava starch, corn, Canavalian ensiformis, and Dioscorea esculenta). This study consists of three main stages, preparation of composite flour, formulation, and artificial rice production using hot extruder capacity 10 kg/day. The objectives of this studies were to investigate some formulation in compare with commercial paddy rice. Artificial rice has been successfully conducted using prototype of hot extruder with the temperature 95°C. Physical analyses (color and water absorption) were carried out to artificial rice product and commercial paddy rice. Chemical analyses (nutrition and amylose content) of product will be also presented in this study. The best formulation of artificial rice was achieved in 80% modified cassava starch, 10% Canavalian ensiformis, and 10% Dioscorea esculenta, respectively.

Engineering Potato Starch with a Higher Phosphate Content

PubMed Central

Xu, Xuan; Huang, Xing-Feng; Visser, Richard G. F.

2017-01-01

Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-binding module and a dual-specificity phosphatase domain, is involved in the dephosphorylation of glycogen. To modify phosphate content and better understand starch (de)phosphorylation in storage starch, laforin was engineered and introduced into potato (cultivar Kardal). Interestingly, expression of an (engineered) laforin in potato resulted in significantly higher phosphate content of starch, and this result was confirmed in amylose-free potato genetic background (amf). Modified starches exhibited altered granule morphology and size compared to the control. About 20–30% of the transgenic lines of each series showed red-staining granules upon incubation with iodine, and contained higher phosphate content than the blue-stained starch granules. Moreover, low amylose content and altered gelatinization properties were observed in these red-stained starches. Principle component and correlation analysis disclosed a complex correlation between starch composition and starch physico-chemical properties. Ultimately, the expression level of endogenous genes involved in starch metabolism was analysed, revealing a compensatory response to the decrease of phosphate content in potato starch. This study provides a new perspective for engineering starch phosphate content in planta by making use of the compensatory mechanism in the plant itself. PMID:28056069

76 FR 19096 - National Starch and Chemical Company, Salisbury, Rowan County, North Carolina; Notice of Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-06

... ENVIRONMENTAL PROTECTION AGENCY [Docket EPA-RO4-SFUND-2011-0278, FRL-9290-7] National Starch and... National Starch and Chemical Company Site located in Salisbury, Rowan County, North Carolina. In the...- SFUND-2011-0278 or Site name National Starch and Chemical Company Superfund Site by one of the following...

Chemical, morphological and functional properties of Brazilian jackfruit (Artocarpus heterophyllus L.) seeds starch.

PubMed

Madruga, Marta Suely; de Albuquerque, Fabíola Samara Medeiros; Silva, Izis Rafaela Alves; do Amaral, Deborah Silva; Magnani, Marciane; Queiroga Neto, Vicente

2014-01-15

Starches used in food industry are extracted from roots, tubers and cereals. Seeds of jackfruit are abundant and contain high amounts of starch. They are discarded during the fruit processing or consumption and can be an alternative source of starch. The starch was extract from the jackfruit seeds and characterised to chemical, morphological and functional properties. Soft and hard jackfruit seeds showed starch content of 92.8% and 94.5%, respectively. Starch granules showed round and bell shape and some irregular cuts on their surface with type-A crystallinity pattern, similar to cereals starches. The swelling power and solubility of jackfruit starch increased with increasing temperature, showing opaque pastes. The soft seeds starch showed initial and final gelatinisation temperature of 36°C and 56°C, respectively; while hard seeds starch presented initial gelatinisation at 40°C and final at 61°C. These results suggest that the Brazilian jackfruit seeds starches could be used in food products. Copyright © 2013 Elsevier Ltd. All rights reserved.

Interfacial rheology of surface-active biopolymers: Acacia senegal gum versus hydrophobically modified starch.

PubMed

Erni, Philipp; Windhab, Erich J; Gunde, Rok; Graber, Muriel; Pfister, Bruno; Parker, Alan; Fischer, Peter

2007-11-01

Acacia gum is a hybrid polyelectrolyte containing both protein and polysaccharide subunits. We study the interfacial rheology of its adsorption layers at the oil/water interface and compare it with adsorbed layers of hydrophobically modified starch, which for economic and political reasons is often used as a substitute for Acacia gum in technological applications. Both the shear and the dilatational rheological responses of the interfaces are considered. In dilatational experiments, the viscoelastic response of the starch derivative is just slightly weaker than that for Acacia gum, whereas we found pronounced differences in shear flow: The interfaces covered with the plant gum flow like a rigid, solidlike material with large storage moduli and a linear viscoelastic regime limited to small shear deformations, above which we observe apparent yielding behavior. In contrast, the films formed by hydrophobically modified starch are predominantly viscous, and the shear moduli are only weakly dependent on the deformation. Concerning their most important technological use as emulsion stabilizers, the dynamic interfacial responses imply not only distinct interfacial dynamics but also different stabilizing mechanisms for these two biopolymers.

Encapsulation and delivery of food ingredients using starch based systems.

PubMed

Zhu, Fan

2017-08-15

Functional ingredients can be encapsulated by various wall materials for controlled release in food and digestion systems. Starch, as one of the most abundant natural carbohydrate polymers, is non-allergenic, GRAS, and cheap. There has been increasing interest of using starch in native and modified forms to encapsulate food ingredients such as flavours, lipids, polyphenols, carotenoids, vitamins, enzymes, and probiotics. Starches from various botanical sources in granular or amorphous forms are modified by chemical, physical, and/or enzymatic means to obtain the desired properties for targeted encapsulation. Other wall materials are also employed in combination with starch to facilitate some types of encapsulation. Various methods of crafting the starch-based encapsulation such as electrospinning, spray drying, antisolvent, amylose inclusion complexation, and nano-emulsification are introduced in this mini-review. The physicochemical and structural properties of the particles are described. The encapsulation systems can positively influence the controlled release of food ingredients in food and nutritional applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urea encapsulation in modified starch matrix for nutrients retention

NASA Astrophysics Data System (ADS)

Naz, Muhammad Yasin; Sulaiman, Shaharin Anwar; Ariff, Mohd. Hazwan Bin Mohd.; Ariwahjoedi, Bambang

2014-10-01

It has been estimated that 20-70% of the used urea goes to the environment via leaching, nitrification and volatilization which not only harms the environment but also reduces the urea efficiency. By coating the urea granules, the farmers can achieve high urea performance through controlling the excess release of nitrogen. Up until now, different materials have been tested for nutrients retention. However, most of them are either expensive or unfriendly to the environment. Being cheap and biodegradable materials, the starches may also be used to coat the urea fertilizer for controlling the nutrients release. However, the pure starches do not meet the standards set by many industrial processes due to their slow tacking and too low viscosities and should be modified for getting smooth, compact and mechanically stronger coatings. In these studies, the tapioca starch was modified by reacting it with urea and different masses of borax. The prepared solutions were used to coat the urea granules of 3.45 mm average diameter. Different volumes (1, 1.5 and 2 mL) of each solution were used to coat 30 g of urea fluidized above the minimum level of fluidization. It was noticed that the coating thickness, percent coating, dissolution rate and percent release follow an increasing trend with an increase of solution volume; however, some random results were obtained while investigating the solution volume effects on the percent release. It was seen that the nutrients percent release over time increases with an increase in solution volume from 1 to 1.5 mL and thereafter reaches to a steady state. It confirms that the 1.5 mL of solution for 30 g urea samples will give the optimized coating results.

Glycemic response to corn starch modified with cyclodextrin glycosyltransferase and its relationship to physical properties

USDA-ARS?s Scientific Manuscript database

Corn starch was modified with cyclodextrin glycosyltransferase (CGTase) below the gelatinization temperature. The porous, partially hydrolyzed, granules with or without CGTase hydrolysis products, cyclodextrins (CDs) and short chain maltodextrins, may be used as an alternative to modified corn starc...

Chemical Composition, Starch Digestibility and Antioxidant Capacity of Tortilla Made with a Blend of Quality Protein Maize and Black Bean

PubMed Central

Grajales-García, Eva M.; Osorio-Díaz, Perla; Goñi, Isabel; Hervert-Hernández, Deisy; Guzmán-Maldonado, Salvador H.; Bello-Pérez, Luis A.

2012-01-01

Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50%) and the predicted glycemic index (88 to 80) of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g) than control tortilla (7.8 μmol Trolox eq/g). The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics. PMID:22312252

Chemical composition, starch digestibility and antioxidant capacity of tortilla made with a blend of quality protein maize and black bean.

PubMed

Grajales-García, Eva M; Osorio-Díaz, Perla; Goñi, Isabel; Hervert-Hernández, Deisy; Guzmán-Maldonado, Salvador H; Bello-Pérez, Luis A

2012-01-01

Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50%) and the predicted glycemic index (88 to 80) of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g) than control tortilla (7.8 μmol Trolox eq/g). The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics.

In vitro Starch Hydrolysis Rate, Physico-chemical Properties and Sensory Evaluation of Butter Cake Prepared Using Resistant Starch Type III Substituted for Wheat Flour.

PubMed

Pongjanta, J; Utaipattanaceep, A; Naivikul, O; Piyachomkwan, K

2008-09-01

Resistant starch type III (RS III) derived from enzymatically debranched high amylose rice starch was prepared and used to make butter cake at different levels (0, 5, 10, 15 and 20%) in place of wheat flour. Physico-chemical properties, sensory evaluation, and in vitro starch hydrolysis rate of the developed butter cake were investigated. This study showed that the content of resistant starch in butter cake increased significantly (P<0.05) as the level of substitution with RS III increased from 2.1 to 4.4% of resistant starch content. The butter cake with RS III replacement had a significantly lower in vitro starch hydrolysis rate compared to the control cake (0% RS III). The rates of starch hydrolysis from 0 to 180 min digestion time for 0, 5, 10 15, and 20% RS III in place of wheat flour in butter cakes were 3.70 to 67.65%, 2.97 to 64.86%, 2.86 to 59.99%, 2.79 to 55.96 and 2.78 to 53.04% respectively. The physico-chemical properties of 5 to 10% RS III substituted with wheat flour in the butter cake were not significantly different from the control cake and were moderately accepted by panellists in the sensory evaluation test.

76 FR 14970 - National Starch and Chemical Company, Salisbury, Rowan County, NC; Notice of Settlement

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-18

... ENVIRONMENTAL PROTECTION AGENCY [Docket EPA-RO4-SFUND-2011-0278, FRL-9284-1] National Starch and... entered into a settlement for reimbursement of past response costs concerning the National Starch and... No. EPA-RO4- SFUND-2011-0278 or Site name National Starch and Chemical Company Superfund Site by one...

Formulation and development of plasma volume expander using natural and modified starch from Solanum tuberosum

PubMed Central

Thombre, Nilima A.; Vishwakarma, Ajit V.; Jadhav, Trupti S.; Kshirsagar, Sanjay J.

2016-01-01

Background: To formulation and development of plasma volume expander (PVE) by using natural and modified starch from Solanum tuberosum. The function of blood circulation is to provide the needs of the body tissues and to maintain an appropriate environment in all tissue fluids of the body for the optimal survival and functions of the cells. Rapid restoration of the blood volume is necessary to decrease reduction in the amount of the blood. The PVEs are isotonic colloidal solutions, act by increasing the osmotic pressure of the intravascular compartment, which leads to the influx of the interstitial fluids through the capillary pore which, in turn, leads to the increase in the volume of the blood. Therefore, there is a need to discover the PVE with less side effects. The main aim of the present study is to use amylopectin as PVEs, fractionated from natural and modified starch obtained from S. tuberosum. Methods: The starch extracted from the normal grains and the tubers of potatoes was selected for the production of starch. Statistical analysis includes in vitro characterization that involves viscosity studies, plasma–product interaction, osmotic pressure detection, molecular weight–viscosity relationship, determination of weight average molecular weight, enzymatic interaction, and in vivo characterization such as toxicity studies and the effect of the products on the blood coagulation. The isolated starch and fractionated amylopectin were analyzed for the physicochemical characteristics. Result and Conclusion: The amylopectin fractionated from isolated starch from grains and tubers of potatoes can be used as PVE, as per the outcome of the study. PMID:28123990

Utilization of a Biodegradable Mulch Sheet Produced from Poly(Lactic Acid)/Ecoflex®/Modified Starch in Mandarin Orange Groves

PubMed Central

Tachibana, Yuya; Maeda, Takuya; Ito, Osamu; Maeda, Yasukatsu; Kunioka, Masao

2009-01-01

We have developed a mulch sheet made by inflation molding of PLA, Ecoflex® and modified starch, which all have different biodegradabilities. A field test of use as an agricultural mulch sheet for mandarin oranges was carried out over two years. The mechanical properties of the mulch sheet were weakened with time during the field test, but the quality of the mandarin oranges increased, a result of the controlled degradation of the sheet. The most degradable modified starch degraded first, allowing control of the moisture on the soil. Accelerator mass spectroscopy was used for evaluation of the biomass carbon ratio. The biomass carbon ratio decreased by degradation of the biobased materials, PLA and modified starch in the mulch sheet. PMID:19812715

Effect of starch type on the physico-chemical properties of edible films.

PubMed

Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

2017-05-01

Food preservation is mostly related to packaging in oil-based plastics, inducing environmental problems, but this drawback could be limited by using edible/biodegradable films and coatings. Physical and chemical properties were assessed and reflect the role of the starch type (wheat, corn or potato) and thus that of the amylose/amylopectin ratio, which influences thickness, colour, moisture, wettability, thermal, surface and mechanical properties. Higher amylose content in films induces higher moisture sensitivity, and thus affects the mechanical and barrier properties. Films made from potato starch constitute a greater barrier for oxygen and water vapour though they have weaker mechanical properties than wheat and corn starch films. Starch species with higher amylose content have lower wettability properties, and better mechanical resistance, which strongly depends on the water content due to the hydrophilic nature of starch films, so they could be used for products with higher water activity, such as cheese, fruits and vegetables. It especially concerns wheat starch systems, and the contact angle indicates less hydrophilic surfaces (above 90°) than those of corn and potato starch films (below 90°). The starch origin influences optical properties and thickness: with more amylose, films are opalescent and thicker; with less, they are transparent and thinner. Copyright © 2017 Elsevier B.V. All rights reserved.

Starch Characteristics Linked to Gluten-Free Products

PubMed Central

Horstmann, Stefan W.; Lynch, Kieran M.; Arendt, Elke K.

2017-01-01

The increasing prevalence of coeliac disease (CD) and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products. PMID:28383504

Starch Characteristics Linked to Gluten-Free Products.

PubMed

Horstmann, Stefan W; Lynch, Kieran M; Arendt, Elke K

2017-04-06

The increasing prevalence of coeliac disease (CD) and gluten-related disorders has led to increasing consumer demand for gluten-free products with quality characteristics similar to wheat bread. The replacement of gluten in cereal-based products remains a challenge for scientists, due to its unique role in network formation, which entraps air bubbles. When gluten is removed from a flour, starch is the main component left. Starch is used as gelling, thickening, adhesion, moisture-retention, stabilizing, film forming, texturizing and anti-staling ingredient. The extent of these properties varies depending on the starch source. The starches can additionally be modified increasing or decreasing certain properties of the starch, depending on the application. Starch plays an important role in the formulation of bakery products and has an even more important role in gluten-free products. In gluten-free products, starch is incorporated into the food formulation to improve baking characteristics such as the specific volume, colour and crumb structure and texture. This review covers a number of topics relating to starch; including; an overview of common and lesser researched starches; chemical composition; morphology; digestibility; functionality and methods of modification. The emphasis of this review is on starch and its properties with respect to the quality of gluten-free products.

Peculiarities of Enhancing Resistant Starch in Ruminants Using Chemical Methods: Opportunities and Challenges

PubMed Central

Deckardt, Kathrin; Khol-Parisini, Annabella; Zebeli, Qendrim

2013-01-01

High-producing ruminants are fed high amounts of cereal grains, at the expense of dietary fiber, to meet their high energy demands. Grains consist mainly of starch, which is easily degraded in the rumen by microbial glycosidases, providing energy for rapid growth of rumen microbes and short-chain fatty acids (SCFA) as the main energy source for the host. Yet, low dietary fiber contents and the rapid accumulation of SCFA lead to rumen disorders in cattle. The chemical processing of grains has become increasingly important to confer their starch resistances against rumen microbial glycosidases, hence generating ruminally resistant starch (RRS). In ruminants, unlike monogastric species, the strategy of enhancing resistant starch is useful, not only in lowering the amount of carbohydrate substrates available for digestion in the upper gut sections, but also in enhancing the net hepatic glucose supply, which can be utilized by the host more efficiently than the hepatic gluconeogenesis of SCFA. The use of chemical methods to enhance the RRS of grains and the feeding of RRS face challenges in the practice; therefore, the present article attempts to summarize the most important achievements in the chemical processing methods used to generate RRS, and review advantages and challenges of feeding RRS to ruminants. PMID:23736826

Nano-encapsulation of coenzyme Q10 using octenyl succinic anhydride modified starch

USDA-ARS?s Scientific Manuscript database

Octenyl succinic anhydride modified starch (OSA-ST) was used to encapsulate Coenzyme Q10 (CoQ10). CoQ10 was dissolved in rice bran oil (RBO), and incorporated into an aqueous OSA-ST solution. High pressure homogenization (HPH) of the mixture was conducted at 170 MPa for 5-6 cycles. The resulting ...

In vitro digestion and physicochemical characteristics of corn starch mixed with amino acid modified by low pressure treatment.

PubMed

Ji, Ying

2018-03-01

The digestibility and molecular structure of corn starch mixed with amino acid modified by low-pressure treatment (LPT) was investigated. Amino acid induced a significant increase in the slowly digestible starch (SDS) and decrease in the rapidly digestible starch (RDS) after LPT. The reason is the formation of ester bond between the molecular chains of amino acid and starch. Low pressure treatment altered greatly the morphology of corn starch mixed with or without amino acid. After LPT, less ordered Maltese and more granule fragments were observed for starch-amino acid complex. An increase in size distribution was obvious after LPT and the size distribution curves provided from a new variety. We found that higher enthalpy and relative crystallinity of the starch-amino acid complex were associated with a higher SDS content. It can be inferred that LPT had a greater impact on the digestion and structural characterization of corn starch mixed with amino acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation and characterization of aminoethyl hydroxypropyl starch modified with collagen peptide.

PubMed

Wen, Huigao; Hu, Jin; Ge, Hongyu; Zou, Shengqiong; Xiao, Yao; Li, Ya; Feng, Han; Fan, Lihong

2017-08-01

The preparation of aminoethyl hydroxypropyl starch collagen peptide (AEHPS-COP) was via an enzyme-catalyzed reaction between amino groups in aminoethyl hydroxypropyl starch (AEHPS) and γ-carboxamide groups in collagen peptide (COP) by using microbial transglutaminase (MTGase) as biocatalyst. As an intermediate reactant, AEHPS was synthesized from hydroxypropyl starch (HPS) and 2-chloroethylamine hydrochloride (CEH). The chemical structures of HPS, AEHPS and AEHPS-COP were characterized by Fourier transform infrared spectroscopy (FT-IR) and 13 C nuclear magnetic resonance ( 13 C NMR). The reaction conditions that influenced the degree of substitution (DS) of AEHPS-COP were optimized, which included the reaction temperature, the reaction time, the mass ratio of collagen peptide to aminoethyl hydroxypropyl starch and the pH value. In addition, in vitro antioxidant activities of AEHPS-COP were evaluated through the scavenging activity of hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Furthermore, the methylthiazol tetrazolium (MTT) assay was applied to investigate the cell viability of AEHPS-COP. The results indicated that the AEHPS-COP exhibited better cell viability to L929 mouse fibroblast cells. Therefore, the AEHPS-COP showed a promising potential application in cosmetic, biomedical and pharmaceutical fields. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of low-fat and low-calorie beef sausage using modified starch as fat replacement agent.

PubMed

Mohammadi, Mehrdad; Oghabi, Firouz

2012-04-01

The effects of modified waxy maize starch (MWMS, 10-32.5 g kg(-1)) as a replacement for varying levels of oil or both oil and wheat flour (WF) on the chemical and technological characteristics of 60% beef sausages were investigated. Addition of MWMS increased water-holding capacity and decreased moisture content and both cooking and purge losses. Incorporation of MWMS improved organoleptic acceptance compared with control sausages. Sausage formula 5 (F5), containing 20 g kg(-1) MWMS and 50 g kg(-1) WF, was better (P < 0.05) than all other formulae. The total caloric content of the sausages decreased significantly with decreasing fat level (P < 0.05); for example, the decrease in fat content of 57.4% in F5 led to a significant decrease in energy value of 34.9% (P < 0.05). Copyright © 2011 Society of Chemical Industry.

Chemical characteristic and functional properties of arenga starch-taro (Colocasia esculanta L.) flour noodle with turmeric extracts addition

NASA Astrophysics Data System (ADS)

Ervika Rahayu N., H.; Ariani, Dini; Miftakhussolikhah, E., Maharani P.; Yudi, P.

2017-01-01

Arenga starch-taro (Colocasia esculanta L.) flour noodle is an alternative carbohydrate source made from 75% arenga starch and 25% taro flour, but it has a different color with commercial noodle product. The addition of natural color from turmeric may change the consumer preference and affect chemical characteristic and functional properties of noodle. This research aims to identify chemical characteristic and functional properties of arenga starch-taro flour noodle with turmeric extract addition. Extraction was performed using 5 variances of turmeric rhizome (0.06; 0.12; 0.18; 0.24; and 0.30 g (fresh weight/ml water). Then, noodle was made and chemical characteristic (proximate analysis) as well as functional properties (amylose, resistant starch, dietary fiber, antioxidant activity) were then evaluated. The result showed that addition of turmeric extract did not change protein, fat, carbohydrate, amylose, and resistant starch content significantly, while antioxidant activity was increased (23,41%) with addition of turmeric extract.

Silicon tetrachloride plasma induced grafting for starch-based composites

NASA Astrophysics Data System (ADS)

Ma, Yonghui C.

Non-modified virgin starch is seldom used directly in industrial applications. Instead, it is often physically and/or chemically modified to achieve certain enhanced properties. For many of the non-food applications, these modifications involve changing its hydrophilicity to create hydrophobic starch. In this study, the hydrophobic starch was produced through silicon tetrachloride (SiCl4) plasma induced graft polymerization, so that it could be used as a renewable and biodegradable component of, or substitute for, the petrochemical-based plastics. It was suggested that this starch graft-copolymer might be used as reinforcing components in silicone-rubber materials for starch-based composites. To make this starch graft-copolymer, the ethyl ether-extracted starch powders were surface functionalized by SiCl4 plasma using a 13.56 MHz radio frequency rotating plasma reactor and subsequently stabilized by either ethylene diamine or dichlorodimethylsilane (DCDMS). The functionalized starch was then graft-polymerized with DCDMS to form polydimethylsiloxane (PDMS) layers around the starch granules. The presence of this PDMS layer was demonstrated by electron spectroscopy for chemical analysis (ESCA/XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), gas chromatography-mass spectroscopy (GC-MS), thermo gravimetry/differential thermal analysis (TG/DTA), and other analyses. It was shown that the surface morphology, thermal properties, swelling characteristic, and hydrophilicity of starch were all changed due to the existence of this protective hydrophobic PDMS layer. Several different procedures to carry out the functionalization and graft polymerization steps were evaluated to improve the effectiveness of the reactions and to prevent the samples from being hydrolyzed by the grafting byproduct HCl. Actinometry, GC-MS, and residual gas analyzer (RGA) were used to investigate the mechanisms of the SiCl4 discharge and to optimize the plasma

Slow digestion property of octenyl succinic anhydride modified waxy maize starch in the presence of tea polyphenols.

PubMed

Peng, Shanli; Xue, Lei; Leng, Xue; Yang, Ruobing; Zhang, Genyi; Hamaker, Bruce R

2015-03-18

The in vivo slow digestion property of octenyl succinic anhydride modified waxy corn starch (OSA-starch) in the presence of tea polyphenols (TPLs) was studied. Using a mouse model, the experimental results showed an extended and moderate postprandial glycemic response with a delayed and significantly decreased blood glucose peak of OSA-starch after cocooking with TPLs (5% starch weight base). Further studies revealed an increased hydrodynamic radius of OSA-starch molecules indicating an interaction between OSA-starch and TPLs. Additionally, decreased gelatinization temperature and enthalpy and reduced viscosity and emulsifiability of OSA-starch support their possible complexation to form a spherical OSA-starch-TPLs (OSAT) complex. The moderate and extended postprandial glycemic response is likely caused by decreased activity of mucosal α-glucosidase, which is noncompetitively inhibited by tea catechins released from the complex during digestion. Meanwhile, a significant decrease of malondialdehyde (MDA) and increased DPPH free radical scavenging activity in small intestine tissue demonstrated the antioxidative functional property of the OSAT complex. Thus, the complex of OSAT, acting as a functional carbohydrate material, not only leads to a flattened and prolonged glycemic response but also reduces the oxidative stress, which might be beneficial to health.

Field testing and exploitation of genetically modified cassava with low-amylose or amylose-free starch in Indonesia.

PubMed

Koehorst-van Putten, H J J; Sudarmonowati, E; Herman, M; Pereira-Bertram, I J; Wolters, A M A; Meima, H; de Vetten, N; Raemakers, C J J M; Visser, R G F

2012-02-01

The development and testing in the field of genetically modified -so called- orphan crops like cassava in tropical countries is still in its infancy, despite the fact that cassava is not only used for food and feed but is also an important industrial crop. As traditional breeding of cassava is difficult (allodiploid, vegetatively propagated, outbreeding species) it is an ideal crop for improvement through genetic modification. We here report on the results of production and field testing of genetically modified low-amylose transformants of commercial cassava variety Adira4 in Indonesia. Twenty four transformants were produced and selected in the Netherlands based on phenotypic and molecular analyses. Nodal cuttings of these plants were sent to Indonesia where they were grown under biosafety conditions. After two screenhouse tests 15 transformants remained for a field trial. The tuberous root yield of 10 transformants was not significantly different from the control. Starch from transformants in which amylose was very low or absent showed all physical and rheological properties as expected from amylose-free cassava starch. The improved functionality of the starch was shown for an adipate acetate starch which was made into a tomato sauce. This is the first account of a field trial with transgenic cassava which shows that by using genetic modification it is possible to obtain low-amylose cassava plants with commercial potential with good root yield and starch quality.

Chemical composition, mineral profile, and functional properties of Canna (Canna edulis) and Arrowroot (Maranta spp.) starches.

PubMed

Pérez, Elevina; Lares, Mary

2005-09-01

The aim of the present study was to evaluate some chemical and mineral characteristics and functional and rheological properties of Canna and Arrowroot starches produced in the Venezuelan Andes. Canna starch showed a higher (P < 0.05) moisture, ash, and crude protein content than arrowroot starch, while crude fiber, crude fat, and amylose content of this starch were higher (P < 0.05). Starches of both rhizomes own phosphorus, sodium, potassium, magnesium, iron, calcium, and zinc in their composition. Phosphorus, sodium, and potassium are the higher in both starches. Water absorption, swelling power, and solubility values revealed weak bonding forces in Canna starch granules; this explained the lower gelatinization temperature and the substantial viscosity development of Canna starch during heating. Arrowroot starch showed a higher gelatinization temperature measure by DSC, than Canna starch and exhibited a lower value of DeltaH. Both starches show negative syneresis. The apparent viscosity of Canna starch was higher (P < 0.05) than the Arrowroot starch values. The size (wide and large) of Canna starch granules was higher than arrowroot starch. From the previous results, it can be concluded that Canna and Arrowroot starches could become interesting alternatives for food developers, depending on their characteristics and functional properties.

Rice starch vs. rice flour: differences in their properties when modified by heat-moisture treatment.

PubMed

Puncha-arnon, Santhanee; Uttapap, Dudsadee

2013-01-02

Starch and flour from the same rice grain source (with 20, 25 and 30% moisture content) were exposed to heat-moisture treatment (HMT) at 100 °C for 16 h in order to investigate whether there were differences in their susceptibility to modification by HMT and, if any, to determine the main causes of the differences. HMT had a far greater effect on paste viscosity of flour than of starch. A significant increase in paste viscosity after removal of proteins from HMT flour - as well as images of fast green-stained HMT flour gels - indicated that an important role was played by proteins in affecting properties of the modified samples. Greater effects of HMT on thermal parameters of gelatinization and gel hardness values of flours were observed - more so than those for starches. Following this observation, it was ascertained that components in rice flour other than rice starch granules also underwent alterations during HMT. Copyright © 2012 Elsevier Ltd. All rights reserved.

Antimicrobial nanostructured starch based films for packaging.

PubMed

Abreu, Ana S; Oliveira, M; de Sá, Arsénio; Rodrigues, Rui M; Cerqueira, Miguel A; Vicente, António A; Machado, A V

2015-09-20

Montmorillonite modified with a quaternary ammonium salt C30B/starch nanocomposite (C30B/ST-NC), silver nanoparticles/starch nanocomposite (Ag-NPs/ST-NC) and both silver nanoparticles/C30B/starch nanocomposites (Ag-NPs/C30B/ST-NC) films were produced. The nanoclay (C30B) was dispersed in a starch solution using an ultrasonic probe. Different concentrations of Ag-NPs (0.3, 0.5, 0.8 and 1.0mM) were synthesized directly in starch and in clay/starch solutions via chemical reduction method. Dispersion of C30B silicate layers and Ag-NPs in ST films characterized by X-ray and scanning electron microscopy showed that the presence of Ag-NPs enhanced clay dispersion. Color and opacity measurements, barrier properties (water vapor and oxygen permeabilities), dynamic mechanical analysis and contact angle were evaluated and related with the incorporation of C30B and Ag-NPs. Films presented antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans without significant differences between Ag-NPs concentrations. The migration of components from the nanostructured starch films, assessed by food contact tests, was minor and under the legal limits. These results indicated that the starch films incorporated with C30B and Ag-NPs have potential to be used as packaging nanostructured material. Copyright © 2015 Elsevier Ltd. All rights reserved.

Application of corona electrical discharge plasma on modifying the physicochemical properties of banana starch indigenous to Taiwan.

PubMed

Wu, Tsung-Yen; Sun, Nan-Nong; Chau, Chi-Fai

2018-01-01

Corona electrical discharge (CED) belongs to an atmospheric pressure cold plasma. In this study, raw banana starch (indigenous to Taiwan), which contained resistant starch and amylose at a level of 58.4 g/100 g and 14.5 g/100 g, respectively, was treated by CED at 30 kV/cm, 40 kV/cm, and 50 kV/cm for 3 minutes. After the CED treatment, starch analyses showed that there were no apparent changes in the resistant starch and amylose contents. Only surface and nonpenetrative damage caused by plasma etching at different voltage strengths were observed on the starch granules. The CED treatments reduced the total area of diffraction peak, gelatinization enthalpy (by -21% to -38%), and different pasting behaviors including peak viscosity, breakdown, final viscosity, and setback. The CED treatments were capable of increasing relative crystallinity and gelatinization temperature. This study revealed the potential of CED plasma technology as a tool to modify the characteristics of banana starch. Copyright © 2017. Published by Elsevier B.V.

Enzymatic modification of corn starch with 4-α-glucanotransferase results in increasing slow digestible and resistant starch.

PubMed

Jiang, Huan; Miao, Ming; Ye, Fan; Jiang, Bo; Zhang, Tao

2014-04-01

In this study, partial 4-α-glucanotransferase (4αGT) treatment was used to modulate the fine structure responsible for the slow digestion and resistant property of starch. Normal corn starch modified using 4αGT for 4h showed an increase of slowly digestible starch from 9.40% to 20.92%, and resistant starch from 10.52 to 17.63%, respectively. The 4αGT treatment decreased the content of amylose from 32.6% to 26.8%. The molecular weight distribution and chain length distribution of 4αGT-treated starch showed a reduction of molecular weight and a great number of short (DP<13) and long (DP>30) chains through cleaving and reorganization of starch molecules. Both the short and long chain fractions of modified amylopectin were attributed to the low in vitro digestibility. The viscosity was inversely related to the digestibility of the 4αGT-treated starch. These results suggested that the 4αGT modified starch synthesized the novel amylopectin clusters with slow digestible and resistant character. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Barley callus: a model system for bioengineering of starch in cereals.

PubMed

Carciofi, Massimiliano; Blennow, Andreas; Nielsen, Morten M; Holm, Preben B; Hebelstrup, Kim H

2012-09-07

Starch is the most important source of calories for human nutrition and the majority of it is produced by cereal farming. Starch is also used as a renewable raw material in a range of industrial sectors. It can be chemically modified to introduce new physicochemical properties. In this way starch is adapted to a variety of specific end-uses. Recombinant DNA technologies offers an alternative to starch industrial processing. The plant biosynthetic pathway can be manipulated to design starches with novel structure and improved technological properties. In the future this may reduce or eliminate the economical and environmental costs of industrial modification. Recently, many advances have been achieved to clarify the genetic mechanism that controls starch biosynthesis. Several genes involved in the synthesis and modification of complex carbohydrates in many organisms have been identified and cloned. This knowledge suggests a number of strategies and a series of candidate genes for genetic transformation of crops to generate new types of starch-based polymers. However transformation of cereals is a slow process and there is no easy model system available to test the efficiency of candidate genes in planta. We explored the possibility to use transgenic barley callus generated from immature embryo for a fast test of transgenic modification strategies of starch biosynthesis. We found that this callus contains 4% (w/w dw) starch granules, which we could modify by generating fully transgenic calli by Agrobacterium-transformation. A Green Fluorescent Protein reporter protein tag was used to identify and propagate only fully transgenic callus explants. Around 1 - 1.5 g dry weight of fully transgenic callus could be produced in 9 weeks. Callus starch granules were smaller than endosperm starch granules and contained less amylose. Similarly the expression profile of starch biosynthesis genes were slightly different in callus compared with developing endosperm. In this study

Barley callus: a model system for bioengineering of starch in cereals

PubMed Central

2012-01-01

Background Starch is the most important source of calories for human nutrition and the majority of it is produced by cereal farming. Starch is also used as a renewable raw material in a range of industrial sectors. It can be chemically modified to introduce new physicochemical properties. In this way starch is adapted to a variety of specific end-uses. Recombinant DNA technologies offers an alternative to starch industrial processing. The plant biosynthetic pathway can be manipulated to design starches with novel structure and improved technological properties. In the future this may reduce or eliminate the economical and environmental costs of industrial modification. Recently, many advances have been achieved to clarify the genetic mechanism that controls starch biosynthesis. Several genes involved in the synthesis and modification of complex carbohydrates in many organisms have been identified and cloned. This knowledge suggests a number of strategies and a series of candidate genes for genetic transformation of crops to generate new types of starch-based polymers. However transformation of cereals is a slow process and there is no easy model system available to test the efficiency of candidate genes in planta. Results We explored the possibility to use transgenic barley callus generated from immature embryo for a fast test of transgenic modification strategies of starch biosynthesis. We found that this callus contains 4% (w/w dw) starch granules, which we could modify by generating fully transgenic calli by Agrobacterium-transformation. A Green Fluorescent Protein reporter protein tag was used to identify and propagate only fully transgenic callus explants. Around 1 – 1.5 g dry weight of fully transgenic callus could be produced in 9 weeks. Callus starch granules were smaller than endosperm starch granules and contained less amylose. Similarly the expression profile of starch biosynthesis genes were slightly different in callus compared with developing

Treatment of high salt oxidized modified starch waste water using micro-electrolysis, two-phase anaerobic aerobic and electrolysis for reuse

NASA Astrophysics Data System (ADS)

Yi, Xuenong; Wang, Yulin

2017-06-01

A combined process of micro-electrolysis, two-phase anaerobic, aerobic and electrolysis was investigated for the treatment of oxidized modified starch wastewater (OMSW). Optimum ranges for important operating variables were experimentally determined and the treated water was tested for reuse in the production process of corn starch. The optimum hydraulic retention time (HRT) of micro-electrolysis, methanation reactor, aerobic process and electrolysis process were 5, 24, 12 and 3 h, respectively. The addition of iron-carbon fillers to the acidification reactor was 200 mg/L while the best current density of electrolysis was 300 A/m2. The biodegradability was improved from 0.12 to 0.34 by micro-electrolysis. The whole treatment was found to be effective with removal of 96 % of the chemical oxygen demand (COD), 0.71 L/day of methane energy recovery. In addition, active chlorine production (15,720 mg/L) was obtained by electrolysis. The advantage of this hybrid process is that, through appropriate control of reaction conditions, effect from high concentration of salt on the treatment was avoided. Moreover, the process also produced the material needed in the production of oxidized starch while remaining emission-free and solved the problem of high process cost.

Formation and stability of Vitamin E enriched nanoemulsions stabilized by Octenyl Succinic Anhydride modified starch

USDA-ARS?s Scientific Manuscript database

Vitamin E (VE) is highly susceptible to autoxidation; therefore, it requires systems to encapsulate and protect it from autoxidation.In this study,we developed VE delivery systems, which were stabilized by Capsul® (MS), a starch modified with octenyl succinic anhydride. Influences of interfacial ten...

Dietary starch intake modifies the relation between copy number variation in the salivary amylase gene and BMI.

PubMed

Rukh, Gull; Ericson, Ulrika; Andersson-Assarsson, Johanna; Orho-Melander, Marju; Sonestedt, Emily

2017-07-01

Background: Studies have shown conflicting associations between the salivary amylase gene ( AMY1 ) copy number and obesity. Salivary amylase initiates starch digestion in the oral cavity; starch is a major source of energy in the diet. Objective: We investigated the association between AMY1 copy number and obesity traits, and the effect of the interaction between AMY1 copy number and starch intake on these obesity traits. Design: We first assessed the association between AMY1 copy number (genotyped by digital droplet polymerase chain reaction) and obesity traits in 4800 individuals without diabetes (mean age: 57 y; 60% female) from the Malmö Diet and Cancer Cohort. Then we analyzed interactions between AMY1 copy number and energy-adjusted starch intake (obtained by a modified diet history method) on body mass index (BMI) and body fat percentage. Results: AMY1 copy number was not associated with BMI ( P = 0.80) or body fat percentage ( P = 0.38). We observed a significant effect of the interaction between AMY1 copy number and starch intake on BMI ( P -interaction = 0.007) and body fat percentage ( P -interaction = 0.03). Upon stratification by dietary starch intake, BMI tended to decrease with increasing AMY1 copy numbers in the low-starch intake group ( P = 0.07) and tended to increase with increasing AMY1 copy numbers in the high-starch intake group ( P = 0.08). The lowest mean BMI was observed in the group of participants with a low AMY1 copy number and a high dietary intake of starch. Conclusions: Our findings suggest an effect of the interaction between starch intake and AMY1 copy number on obesity. Individuals with high starch intake but low genetic capacity to digest starch had the lowest BMI, potentially because larger amounts of undigested starch are transported through the gastrointestinal tract, contributing to fewer calories extracted from ingested starch. © 2017 American Society for Nutrition.

Evaluation studies on the combined effect of hydrothermal treatment and octenyl succinylation on the physic-chemical, structural and digestibility characteristics of sweet potato starch.

PubMed

Lv, Qing-Qing; Li, Gao-Yang; Xie, Qiu-Tao; Zhang, Bao; Li, Xiao-Min; Pan, Yi; Chen, Han-Qing

2018-08-01

In order to increase the degree of substitution (DS), a combination of heat-moisture treatment (HMT) and octenyl succinylation (OSA) was used to modify sweet potato starch (SPS). The content of OSA had significant influence on the DS of starch, and DS of HMT OSA-modified SPS (HOSA-SPS) was higher than that of OSA-modified SPS (OSA-SPS), indicating that prior HMT could enhance the reaction. HOSA-SPS showed higher contents of SDS and RS in comparison with OSA-SPS as OSA concentration was beyond 6%. HMT decreased swelling power of starch while OSA modification had a contrary role (p < 0.05). Scanning electron microscopy (SEM) showed starch was destroyed by OSA modification while HMT had slight effect on the structure. X-ray diffraction (XRD) indicated that crystal type of starch was transformed from C- to A-type resulted from HMT, and remained unchanged by OSA modification. The onset, peak, and conclusion gelatinization temperatures of starch increased by HMT and decreased by OSA modification (p < 0.05). Copyright © 2018 Elsevier Ltd. All rights reserved.

Study of heat-moisture treatment of potato starch granules by chemical surface gelatinization.

PubMed

Bartz, Josiane; da Rosa Zavareze, Elessandra; Dias, Alvaro Renato Guerra

2017-08-01

Native potato starch was subjected to heat-moisture treatment (HMT) at 12%, 15%, 18%, 21%, and 24% of moisture content at 110 °C for 1 h, and the effects on morphology, structure, and thermal and physicochemical properties were investigated. To reveal the internal structure, 30% and 50% of the granular surface were removed by chemical surface gelatinization in concentrated LiCl solution. At moisture contents of 12% and 15%, HTM reduced the gelatinization temperatures and relative crystallinity of the starches, while at moisture contents of 21% and 24 % both increased. The alterations on morphology, X-ray pattern, physicochemical properties, and increase of amylose content were more intense with the increase of moisture content of HMT. The removal of granular layers showed that the changes promoted by HMT occur throughout the whole granule and were pronounced at the core or peripheral region, depending of the moisture content applied during HMT. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Comparison of ambient solvent extraction methods for the analysis of fatty acids in non-starch lipids of flour and starch

PubMed Central

Bahrami, Niloufar; Yonekura, Lina; Linforth, Robert; Carvalho da Silva, Margarida; Hill, Sandra; Penson, Simon; Chope, Gemma; Fisk, Ian Denis

2014-01-01

BACKGROUND Lipids are minor components of flours, but are major determinants of baking properties and end-product quality. To the best of our knowledge, there is no single solvent system currently known that efficiently extracts all non-starch lipids from all flours without the risk of chemical, mechanical or thermal damage. This paper compares nine ambient solvent systems (monophasic and biphasic) with varying polarities: Bligh and Dyer (BD); modified Bligh and Dyer using HCl (BDHCL); modified BD using NaCl (BDNaCl); methanol–chloroform–hexane (3:2:1, v/v); Hara and Radin (hexane–isopropanol, 3:2, v/v); water-saturated n-butanol; chloroform; methanol and hexane for their ability to extract total non-starch lipids (separated by lipid classes) from wheat flour (Triticum aestivum L.). Seven ambient extraction protocols were further compared for their ability to extract total non-starch lipids from three alternative samples: barley flour (Hordeum vulgare L.), maize starch (Zea mays L.) and tapioca starch (Manihot esculenta Crantz). RESULTS For wheat flour the original BD method and those containing HCl or NaCl tended to extract the maximum lipid and a significant correlation between lipid extraction yield (especially the glycolipids and phospholipids) and the polarity of the solvent was observed. For the wider range of samples BD and BD HCl repeatedly offered the maximum extraction yield and using pooled standardized (by sample) data from all flours, total non-starch lipid extraction yield was positively correlated with solvent polarity (r = 0.5682, P < 0.05) and water ratio in the solvent mixture (r = 0.5299, P < 0.05). CONCLUSION In general, BD-based methods showed better extraction yields compared to methods without the addition of water and, most interestingly, there was much greater method dependence of lipid yields in the starches when compared to the flour samples, which is due to the differences in lipid profiles between the two sample types (flours and

Gelatin- and starch-based hydrogels. Part A: Hydrogel development, characterization and coating.

PubMed

Van Nieuwenhove, Ine; Salamon, Achim; Peters, Kirsten; Graulus, Geert-Jan; Martins, José C; Frankel, Daniel; Kersemans, Ken; De Vos, Filip; Van Vlierberghe, Sandra; Dubruel, Peter

2016-11-05

The present work aims at constructing the ideal scaffold matrix of which the physico-chemical properties can be altered according to the targeted tissue regeneration application. Ideally, this scaffold should resemble the natural extracellular matrix (ECM) as close as possible both in terms of chemical composition and mechanical properties. Therefore, hydrogel films were developed consisting of methacrylamide-modified gelatin and starch-pentenoate building blocks because the ECM can be considered as a crosslinked hydrogel network consisting of both polysaccharides and structural, signaling and cell-adhesive proteins. For the gelatin hydrogels, three different substitution degrees were evaluated including 31%, 72% and 95%. A substitution degree of 32% was applied for the starch-pentenoate building block. Pure gelatin hydrogels films as well as interpenetrating networks with gelatin and starch were developed. Subsequently, these films were characterized using gel fraction and swelling experiments, high resolution-magic angle spinning (1)H NMR spectroscopy, rheology, infrared mapping and atomic force microscopy. The results indicate that both the mechanical properties and the swelling extent of the developed hydrogel films can be controlled by varying the chemical composition and the degree of substitution of the methacrylamide-modified gelatin applied. The storage moduli of the developed materials ranged between 14 and 63kPa. Phase separation was observed for the IPNs for which separated starch domains could be distinguished located in the surrounding gelatin matrix. Furthermore, we evaluated the affinity of aggrecan for gelatin by atomic force microscopy and radiolabeling experiments. We found that aggrecan can be applied as a bioactive coating for gelatin hydrogels by a straightforward physisorption procedure. Thus, we achieved distinct fine-tuning of the physico-chemical properties of these hydrogels which render them promising candidates for tissue engineering

Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch.

PubMed

Wokadala, Obiro Cuthbert; Emmambux, Naushad Mohammad; Ray, Suprakas Sinha

2014-11-04

In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dynamic moisture sorption characteristics of enzyme-resistant recrystallized cassava starch.

PubMed

Mutungi, Christopher; Schuldt, Stefan; Onyango, Calvin; Schneider, Yvonne; Jaros, Doris; Rohm, Harald

2011-03-14

The interaction of moisture with enzyme-resistant recrystallized starch, prepared by heat-moisture treatment of debranched acid-modified or debranched non-acid-modified cassava starch, was investigated in comparison with the native granules. Crystallinities of the powdered products were estimated by X-ray diffraction. Moisture sorption was determined using dynamic vapor sorption analyzer and data fitted to various models. Percent crystallinities of native starch (NS), non-acid-modified recrystallized starch (NAMRS), and acid-modified recrystallized starch (AMRS) were 39.7, 51.9, and 56.1%, respectively. In a(w) below 0.8, sorption decreased in the order NS > NAMRS > AMRS in line with increasing sample crystallinities but did not follow this crystallinity dependence at higher a(w) because of condensation and polymer dissolution effects. Adsorbed moisture became internally absorbed in NS but not in NAMRS and AMRS, which might explain the high resistance of the recrystallized starches to digestion because enzyme and starch cannot approach each other over fairly sufficient surface at the molecular level.

Effects of cyclodextrin glycosiltransferase modified starch and cyclodextrins on plasma glucose and lipids metabolism in mice

USDA-ARS?s Scientific Manuscript database

The potential functional and nutritional benefits of granular starch treated with cyclodextrin glycosyltransferase (CGTase) and the released cyclodextrins (CDs) were explored in in vivo studies. The metabolic effects of diets in the C57BL/6J mouse containing native and enzymatically modified corn st...

Using heat-treated starch to modify the surface of biochar and improve the tensile properties of biochar-filled stryene-butadiene rubber composites

USDA-ARS?s Scientific Manuscript database

Heat-treated starch is a renewable material that can be used to modify the surface chemistry of small particles. In this work, heat-treated starch was used to coat hydrophilic biochar particles in order to make them more hydrophobic. Then when added as filler to hydrophobic styrene-butadiene rubber,...

Optimization of Extrusion Process of Directly Expanded Snacks Based on Potato Starch in a Single Step for the Formation of Type IV Resistant Starch.

PubMed

Calvo-López, Amira Daniela; Martínez-Bustos, Fernando

2017-09-01

Resistant starch type IV (RSIV) can be produced by chemical modifications (etherized or esterified) such as conversion, substitution, or cross-linking, which can prevent its digestion by blocking enzyme access and forming atypical linkages. In this research, the effects of barrel temperature (145.86-174.14 °C), the screw speed (42.93-57.07 Hz) and derivatization (esterification) in the formation of RSIV content of directly expanded snacks (second generation snacks) were studied. Potato starch was chemically modified by phosphorylation and succinylation, and expanded by using the extrusion cooking process. Snacks with phosphorylated starch showed expansion index from 2.57 to 3.23, bulk density from 306.19 to 479.00 kg/m 3 and RSIV from 43.27 to 55.81%. Snacks with succinylated starch had expansion index from 3.52 to 3.82, bulk density from 99.85 to 134.51 kg/m 3 and RSIV from 23.17 to 35.01%. The results found in this work showed that it is possible to manufacture extruded directly expanded snacks (second-generation snacks) such as a ready-to-eat (RTE) with good physicochemical properties and without substantial loss of extrusion functionality, which could bring a healthy benefit due to the presence of RSIV.

Swelling and tensile properties of starch glycerol system with various crosslinking agents

NASA Astrophysics Data System (ADS)

Mohamed, R.; Mohd, N.; Nurazzi, N.; Siti Aisyah, M. I.; Fauzi, F. Mohd

2017-07-01

Brittle properties of starch had been overcome by the modification process. In this work, sago starch is being modified with variable amount of plasticiser, namely glycerol at 20 and 40% and crosslinking agent had been added to the system. The film of the modification and characterizations of the starch glycerol system with various crosslinking systems were produced by casting method. The film properties of the starch glycerol system were then characterized by tensile strength (mechanical properties) and swelling (physical properties). The modification of the starch glycerol had improved that system by increasing the tensile strength, modulus however lowering its elongation. The increasing in percentage of the water absorption and also swelling are due to the intrinsic hydroxyl groups presence from the starch and glycerol itself that can attract more water to the system. Upon crosslinking, films casted with chemicals namely, glyoxal, malonic acid, borax, PEG were characterised. It was found that, all the film of sago starch crosslinked and undergoing easy film formation. From this modification, borax and malonic acid crosslinking agent had been determined as the best crosslinking agent to the starch glycerol system.

Comparison of waxy and normal potato starch remaining granules after chemical surface gelatinization: pasting behavior and surface morphology.

PubMed

Huang, Junrong; Chen, Zhenghong; Xu, Yalun; Li, Hongliang; Liu, Shuxing; Yang, Daqing; Schols, Henk A

2014-02-15

To understand the contribution of granule inner portion to the pasting property of starch, waxy potato starch and two normal potato starches and their acetylated starch samples were subjected to chemical surface gelatinization by 3.8 mol/L CaCl2 to obtain remaining granules. Native and acetylated, original and remaining granules of waxy potato starch had similar rapid visco analyzer (RVA) pasting profiles, while those of two normal potato starches behaved obviously different from each other. All remaining granules had lower peak viscosity than the corresponding original granules. Contribution of waxy potato starch granule's inner portion to the peak viscosity was significant more than those of normal potato starches. The shell structure appearing on the remaining granule surface for waxy potato starch was smoother and thinner than that for normal potato starches as observed by scanning electron microscopy, indicating a more regular structure of shell and a more ordered packing of shell for waxy potato starch granules. The blocklet size of waxy potato starch was smaller and more uniform than those of normal potato starches as shown by atomic force microscopy images of original and remaining granules. In general, our results provided the evidence for the spatial structure diversity between waxy and normal potato starch granules: outer layer and inner portion of waxy potato starch granule had similar structure, while outer layer had notably different structure from inner portion for normal potato starch granule. Copyright © 2013 Elsevier Ltd. All rights reserved.

Starch-based xerogels: Effect of acetylation on Physicochemical and rheological properties.

PubMed

Kemas, Chinwe U; Ngwuluka, Ndidi C; Ochekpe, Nelson A; Nep, Elijah I

2017-05-01

This study was aimed at evaluating the physicochemical and rheological properties of starch-based xerogels. The starch from the shoots of Borassus aethiopium was physically modified by xerogelization, and chemically by acetylation, and combination of acetylation and xerogelization. The solubility, swelling and syneresis of the starches were determined by gravimetric techniques. Evaluation of the native starch and derivatives was done using microscopy, Fourier transform infra-red (FTIR), x-ray diffractometry (XRD), and 1 H NMR spectroscopy. Rheological evaluation was done on 10%w/v dispersions using a Bohlin Gemini rheometer (fitted with a 55mm and 2° cone and plate geometry with gap of 70). The diffractograms displayed three peaks, centered on 2θ=15.3, 17.2 and 23.1° for the native and the starch acetate while the xerogel and the starch acetate xerogel were amorphous. The 1 H NMR and FTIR confirmed the presence of acetyl groups at about 2.05ppm and 1720cm -1 , respectively. Acetylation of the native starch resulted in improvement of solubility. The starch acetate-xerogel sample formed viscoelastic gels without the need for heating. Acetylation and/or xerogelization of the native starch inhibited syneresis. Starch acetate-xerogels, may find application as stabilizer or suspending agent in liquid food and pharmaceutical formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of Resistant Starches in Rat Cecal Contents Using Fourier Transform Infrared Photoacoustic Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Timothy J.; Ai, Yongfeng; Jones, Roger W.

Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) qualitatively and quantitatively measured resistant starch (RS) in rat cecal contents. Fisher 344 rats were fed diets of 55% (w/w, dry basis) starch for 8 weeks. Cecal contents were collected from sacrificed rats. A corn starch control was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. To calibrate the FTIR-PAS analysis, samples from each diet were analyzed using an enzymatic assay. A partial least-squares cross-validation plot generated from the enzymatic assay and FTIR-PAS spectral results for starch fitmore » the ideal curve with a R2 of 0.997. A principal component analysis plot of components 1 and 2 showed that spectra from diets clustered significantly from each other. This study clearly showed that FTIR-PAS can accurately quantify starch content and identify the form of starch in complex matrices.« less

Effect of algal flocculation on dissolved organic matters using cationic starch modified soils.

PubMed

Shi, Wenqing; Bi, Lei; Pan, Gang

2016-07-01

Modified soils (MSs) are being increasingly used as geo-engineering materials for the sedimentation removal of cyanobacterial blooms. Cationic starch (CS) has been tested as an effective soil modifier, but little is known about its potential impacts on the treated water. This study investigated dissolved organic matters in the bloom water after algal removal using cationic starch modified soils (CS-MSs). Results showed that the dissolved organic carbon (DOC) could be decreased by CS-MS flocculation and the use of higher charge density CS yielded a greater DOC reduction. When CS with the charge density of 0.052, 0.102 and 0.293meq/g were used, DOC was decreased from 3.4 to 3.0, 2.3 and 1.7mg/L, respectively. The excitation-emission matrix fluorescence spectroscopy and UV254 analysis indicated that CS-MS exhibits an ability to remove some soluble organics, which contributed to the DOC reduction. However, the use of low charge density CS posed a potential risk of DOC increase due to the high CS loading for effective algal removal. When CS with the charge density of 0.044meq/g was used, DOC was increased from 3.4 to 3.9mg/L. This study suggested, when CS-MS is used for cyanobacterial bloom removal, the content of dissolved organic matters in the treated water can be controlled by optimizing the charge density of CS. For the settled organic matters, other measures (e.g., capping treatments using oxygen loaded materials) should be jointly applied after algal flocculation. Copyright © 2016. Published by Elsevier B.V.

Changes in protein and starch digestibility in sorghum flour during heat-moisture treatments.

PubMed

Vu, Thanh-Hien; Bean, Scott; Hsieh, Chao-Feng; Shi, Yong-Cheng

2017-11-01

Heat-moisture treatment (HMT) has been used to modify properties of sorghum starches. However, information is limited on the effects of HMT on the digestibility of starch and the concurrent changes in protein in sorghum flour. The objectives of this research were to identify heat-moisture conditions to increase the resistant starch (RS) content of sorghum flour and investigate changes in sorghum proteins and starch structure. Sorghum flours with different moisture contents (0, 125, 200, and 300 g kg -1 w.b.) were heated at three temperatures (100, 120 and 140 °C) and times (1, 2 and 4 h). HMT of sorghum flour increased its RS level. The flour treated at 200 g kg -1 moisture and 100 °C for 4 h had a high RS content (221 g kg -1 vs. 56 g kg -1 for the untreated flour). Starch was not gelatinized when sorghum flours heated at moisture content of 200 g kg -1 or below. Sorghum protein digestibility and solubility decreased during HMT. The increase in RS of sorghum flour upon HMT was attributed to enhanced amylose-lipid complexes and heat induced structural changes in its protein fraction. HMT can be used to increase RS content in sorghum flour without gelatinizing its starch, thereby providing sorghum flour with unique food applications. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Elucidation of stabilizing oil-in-water Pickering emulsion with different modified maize starch-based nanoparticles.

PubMed

Ye, Fan; Miao, Ming; Jiang, Bo; Campanella, Osvaldo H; Jin, Zhengyu; Zhang, Tao

2017-08-15

The aim of present study was to study the medium-chain triacylglycerol-in-water (O/W) Pickering emulsion stabilized using different modified starch-based nanoparticles (octenylsuccinylation treated soluble starch nanoparticle, OSA-SSNP, and insoluble starch nanoparticle, ISNP). The major factors for affecting the system stability, rheological behaviour and microstructure of the emulsions were also investigated. The parameters of the O/W emulsions stabilized by OSA-SSNP or ISNP were selected as follows: 3.0% of starch nanoparticles concentration, 50% of MCT fraction and 7.0 of system pH. The rheological properties indicated that both emulsions displayed shear-thinning behaviour as a non-Newtonian fluid. For OSA-SSNP, the viscosities of the emulsion were higher than those of ISNP throughout shear rate range for the same condition. The plot of droplet size distribution for emulsion stabilized OSA-SSNP appeared as a single narrow peak, whereas a broader droplet size distribution with bimodal pattern was observed for emulsion stabilized ISNP. The microscopy results showed that both OSA-SSNP and ISNP were adsorbed at oil-water interface to form a barrier film and retard the phase separation. When emulsion was stored for 30d, no phase separation was detected for O/W emulsion, revealing high stability of emulsion stabilized by both OSA-SSNP and ISNP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of single and dual physical modifications on pinhão starch.

PubMed

Pinto, Vânia Zanella; Vanier, Nathan Levien; Deon, Vinicius Gonçalves; Moomand, Khalid; El Halal, Shanise Lisie Mello; Zavareze, Elessandra da Rosa; Lim, Loong-Tak; Dias, Alvaro Renato Guerra

2015-11-15

Pinhão starch was modified by annealing (ANN), heat-moisture (HMT) or sonication (SNT) treatments. The starch was also modified by a combination of these treatments (ANN-HMT, ANN-SNT, HMT-ANN, HMT-SNT, SNT-ANN, SNT-HMT). Whole starch and debranched starch fractions were analyzed by gel-permeation chromatography. Moreover, crystallinity, morphology, swelling power, solubility, pasting and gelatinization characteristics were evaluated. Native and single ANN and SNT-treated starches exhibited a CA-type crystalline structure while other modified starches showed an A-type structure. The relative crystallinity increased in ANN-treated starches and decreased in single HMT- and SNT-treated starches. The ANN, HMT and SNT did not provide visible cracks, notches or grooves to pinhão starch granule. SNT applied as second treatment was able to increase the peak viscosity of single ANN- and HMT-treated starches. HMT used alone or in dual modifications promoted the strongest effect on gelatinization temperatures and enthalpy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dry Starch Powders Modified Teabag Method

EPA Pesticide Factsheets

The following is a test protocol for a “tea bag analysis” that was conducted on PMN starches by the Corn Refiners Association. This protocol is one approach to providing information on swellability of high molecular weight polymers.

Impact of amylosucrase modification on the structural and physicochemical properties of native and acid-thinned waxy corn starch.

PubMed

Zhang, Hao; Zhou, Xing; He, Jian; Wang, Tao; Luo, Xiaohu; Wang, Li; Wang, Ren; Chen, Zhengxing

2017-04-01

Recombinant amylosucrase from Neisseria polysaccharea was utilized to modify native and acid-thinned starches. The molecular structures and physicochemical properties of modified starches were investigated. Acid-thinned starch displayed much lower viscosity after gelatinization than did the native starch. However, the enzyme exhibited similar catalytic efficiency for both forms of starch. The modified starches had higher proportions of long (DP>33) and intermediate chains (DP 13-33), and X-ray diffraction showed a B-type crystalline structure for all modified starches. With increasing reaction time, the relative crystallinity and endothermic enthalpy of the modified starches gradually decreased, whereas the melting peak temperatures and resistant starch contents increased. Slight differences were observed in thermal parameters, relative crystallinity, and branch chain length distribution between the modified native and acid-thinned starches. Moreover, the digestibility of the modified starches was not affected by acid hydrolysis pretreatment, but was affected by the percentage of intermediate and long chains. Copyright © 2016 Elsevier Ltd. All rights reserved.

Paraformaldehyde-Resistant Starch-Fermenting Bacteria in “Starch-Base” Drilling Mud

PubMed Central

Myers, G. E.

1962-01-01

Starch-fermenting bacteria were found in each of 12 samples of nonfermenting starch-base drilling mud examined. Of the 12 samples, 3 contained very active starch-fermenting gram-positive spore-bearing bacilli closely resembling Bacillus subtilis. Similar active starch-fermenting bacteria were found in fermenting starch-base drilling mud and in corn starch and slough water used to prepare such mud. The active starch-fermenting microorganisms completely hydrolyzed 1% (w/v) corn starch within 24 hr at 37.5 C. The active starch-fermenting bacteria isolated from fermenting drilling mud were capable of surviving 12 hr of continuous exposure to 0.1% (w/w) paraformaldehyde or 1 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, with no diminution in starch-fermenting ability. The same organisms fermented starch after 3 hr of continuous exposure to 0.5% (w/w) paraformaldehyde, but not after 4 hr of exposure. The phenomenon of rapid disappearance of paraformaldehyde from fermenting drilling mud was observed in the laboratory using a modified sodium sulfite test. Paraformaldehyde, initially present in a concentration of 0.192 lb per barrel of mud, completely disappeared in 9 hr at 22 to 23 C. A significant decrease in paraformaldehyde concentration was detected 0.5 hr after preparation of the mud. It is suggested that the presence of relatively high concentrations of ammonia and chloride in the mud may facilitate the disappearance of paraformaldehyde. The failure of 0.1% (w/w) paraformaldehyde to inhibit the strong starch-fermenting microorganisms isolated from fermenting drilling mud, and the rapid disappearance of paraformaldehyde from the mud, explains the fermentation of starch which occurred in this mud, despite the addition of paraformaldehyde. PMID:13936949

Isolation and characterisation of nanoparticles from tef and maize starch modified with stearic acid.

PubMed

Cuthbert, Wokadala O; Ray, Suprakas S; Emmambux, Naushad M

2017-07-15

Nanoparticles were isolated from tef and maize starch modified with added stearic acid after pasting at 90°C for 130min. This was followed by thermo-stable alpha-amylase hydrolysis of the paste. The resultant residues were then characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic laser scattering particle size distribution (DLPSD), atomic force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM). XRD and DSC showed that the isolated residues consisted of amylose-lipid complexes. These complexes were type II with melting temperature above 104°C. DLPSD, AFM and HRTEM showed that the isolated tef and maize starch residues consisted of nanoparticles which became more distinct with increased hydrolysis time. The isolated tef and maize nanoparticles had distinct particles of about 3-10nm and 2.4-6.7nm, respectively and the yield was about 24-30%. The results demonstrated that distinct (physically separate) nanoparticles of less than 10nm can be isolated after formation during pasting of tef and maize starch with stearic acid. The production and isolation of the nanoparticles uses green chemistry principles and these nanoparticles can be used in food and non-food systems as nanofillers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of PLA-Starch Fibers

USDA-ARS?s Scientific Manuscript database

Composites of polylactic acid (PLA) with starch have been prepared previously in an effort to reduce cost as well as to modify other properties such as biodegradation rate. However, strength and elongation both decrease on addition of starch due to poor adhesion and stress concentration at the inte...

Chemical and functional properties of cassava starch, durum wheat semolina flour, and their blends

PubMed Central

Oladunmoye, Olufunmilola O; Aworh, Ogugua C; Maziya-Dixon, Bussie; Erukainure, Ochuko L; Elemo, Gloria N

2014-01-01

High-quality cassava starch (HQCS) produced from high-yielding low-cyanide improved cassava variety, TMS 30572, was mixed with durum wheat semolina (DWS) on a replacement basis to produce flour samples containing 0, 20, 30, 50, 70, and 100% cassava starch. They were analyzed for chemical composition (proximate, amylose, free sugars, starch, wet gluten, and cyanide) and functional properties (pasting, swelling power, solubility, water absorption, water binding, starch damage, diastatic and α-amylase activity, dough mixing, and stability). Protein, carbohydrate, fat, and ash of flour samples ranged from 0.75–12.31%, 70.87–87.80%, 0.95–4.41%, and 0.12–0.83%, respectively. Cyanide levels in all the flour samples were less than 0.1 ppm. Amylose content varied between 19.49% for cassava and 28.19% for wheat, correlating significantly with protein (r = 0.95, P = 0.004) and ash contents (r = 0.92, P = 0.01) at 5%. DWS and HQCS had similar pasting temperatures (50.2–53°C), while other pasting properties increased with increasing levels of HQCS. Dough mixing stability of samples decreased with increasing levels of HQCS. All the flour samples had α-amylase activity greater than 200. Both HQCS and DWS compare favorably well in swelling power (7.80–9.01%); but the solubility of wheat starch doubled that of cassava. Starch damage varied between 3.3 and 7.2 AACC for semolina and starch, with the latter having higher absorption rate (97%), and the former, higher absorption speed (67 sec). Results obtained showed positive insight into cassava–wheat blend characteristics. Data thus generated provide additional opportunities of exploiting cassava utilization and hence boost its value–addition potentials for product development. PMID:24804071

Effect of molecular weight profile of sorghum proanthocyanidins on resistant starch formation.

PubMed

Barros, Frederico; Awika, Joseph; Rooney, Lloyd W

2014-04-01

There is a growing interest to increase resistant starch (RS) in foods through natural modification of starch. Sorghum tannins (proanthocyanidins, PAs) were recently reported to interact with starch, increasing RS. However, there is no information about how the molecular weight profile of PAs affects RS formation. This study investigated how different-molecular-weight PAs from sorghum affected RS formation in different starch models. The levels of RS were higher (331-437 mg g(-1)) when high-amylose starch was cooked with phenolic extracts containing mostly high-molecular-weight PAs compared with extracts containing lower-molecular-weight PAs or monomeric catechin (249-285 mg g(-1)). In general, binding capacity of PAs with amylose increased proportionally with molecular weight. For example, the percentage of PAs bound to amylose increased from 45% (PAs with degree of polymerization (DP) = 6) to 94% (polymeric PAs, DP > 10). The results demonstrate that molecular weight of the PAs directly affects their interaction with starch: the higher the molecular weight, the stronger the binding to amylose and the higher the RS formation. Polymeric PAs from sorghum can naturally modify starch by interacting strongly with amylose and are thus most suitable to produce foods with higher RS. © 2013 Society of Chemical Industry.

Chemical modification with phthalic anhydride and chitosan: Viable options for the stabilization of raw starch digesting amylase from Aspergillus carbonarius.

PubMed

Nwagu, Tochukwu Nwamaka; Okolo, Bartholomew; Aoyagi, Hideki; Yoshida, Shigeki

2017-06-01

The raw starch digesting type of amylase (RSDA) presents greater opportunities for process efficiency at cheaper cost and shorter time compared to regular amylases. Chemical modification is a simple and rapid method toward their stabilization for a wider application. RSDA from Aspergillus carbonarius was modified with either phthalic anhydride (PA) or chitosan. Activity retention was 87.3% for PA-modified and 80.9% for chitosan-modified RSDA. Optimum pH shifted from 5 to 7 after PA-modification. Optimum temperature changed from 30°C (native) to 30-40°C and 60°C for PA-modified and chitosan-modified, respectively. Activation energy (kJmol -1 ) for hydrolysis was 13.5, 12.7, and 10.2 while the activation energy for thermal denaturation was 32.8, 80.3, 81.9 for free, PA-modified and chitosan-modified, respectively. The specificity constants (V max /K m ) were 73.2 for PA-modified, 63.1 for chitosan-modified and 77.1 for native RSDA. The half-life (h) of the RSDA at 80°C was increased from 6.1 to 25.7 for the PA-modified and 138.6 for the chitosan derivative. Modification also led to increase in D value, activation enthalpy and Gibbs free energy of enzyme deactivation. Fluorescence spectra showed that center of spectral mass decreased for the PA-modified RSDA but increased for chitosan modified RSDA. Copyright © 2017 Elsevier B.V. All rights reserved.

In vitro digestibility of banana starch cookies.

PubMed

Bello-Pérez, Luis A; Sáyago-Ayerdi, Sonia G; Méndez-Montealvo, Guadalupe; Tovar, Juscelino

2004-01-01

Banana starch was isolated and used for preparation of two types of cookies. Chemical composition and digestibility tests were carried out on banana starch and the food products, and these results were compared with corn starch. Ash, protein, and fat levels in banana starch were higher than in corn starch. The high ash amount in banana starch could be due to the potassium content present in this fruit. Proximal analysis was similar between products prepared with banana starch and those based on corn starch. The available starch content of the banana starch preparation was 60% (dmb). The cookies had lower available starch than the starches while banana starch had lower susceptibility to the in vitro alpha-amylolysis reaction. Banana starch and its products had higher resistant starch levels than those made with corn starch.

Development of native and modified banana starch nanoparticles as vehicles for curcumin.

PubMed

Acevedo-Guevara, Leonardo; Nieto-Suaza, Leonardo; Sanchez, Leidy T; Pinzon, Magda I; Villa, Cristian C

2018-05-01

In recent years, starch nanoparticles have been of great interest for drug delivery due to their relatively easy synthesis, biocompatibility, and vast amount of botanical sources. Native and acetylated starch obtained from green bananas were used for synthesis of curcumin-loaded starch nanoparticles. Mean particle size, encapsulation efficiency, and curcumin release in simulated gastric and intestinal fluids were studied. Both nanosystems showed sizes lower than 250 nm and encapsulation efficiency above 80%, with acetylated banana starch nanoparticles having the capacity to encapsulate more curcumin molecules. Both FTIR and XRD analyses showed that starch acetylation allows stronger hydrogen bond interaction between curcumin and the starch matrix, thus, higher encapsulation efficiency. Finally, curcumin release studies showed that acetylated banana starch nanoparticles allowed more controlled release, probably due to their stronger hydrogen bond interaction with curcumin. Copyright © 2018. Published by Elsevier B.V.

Effect on in vitro starch digestibility of Mexican blue maize anthocyanins.

PubMed

Camelo-Méndez, Gustavo A; Agama-Acevedo, Edith; Sanchez-Rivera, Mirna M; Bello-Pérez, Luis A

2016-11-15

The purpose of this study was to evaluate the effect of blue maize extracts obtained by acid-methanol treatment on the nutritional in vitro starch fractions such as: rapidly digestive starch (RDS), slowly digestive starch (SDS) and resistant starch (RS) of native and gelatinized commercial maize starch. Chromatographic analysis (HPLC-DAD/ESI-MS) of blue maize extracts showed the presence of seven anthocyanins, where cyanidin-3-(6″-malonylglucoside) was the main. Blue maize extracts modified nutritional in vitro starch fractions (decrease of RDS) while RS content increased (1.17 and 2.02 times for native and gelatinized commercial maize starch, respectively) when anthocyanins extracts were added to starch up to 75% (starch weight). This preliminary observation provides the basis for further suitability evaluation of blue maize extract as natural starch-modifier by the possible anthocyanins-starch interaction. Anthocyanin extracts can be a suitable to produce functional foods with higher RS content with potential human health benefits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microstructural and techno-functional properties of cassava starch modified by ultrasound.

PubMed

Monroy, Yuliana; Rivero, Sandra; García, María A

2018-04-01

This work was focused on the correlation between the structural and techno-functional properties of ultrasound treated cassava starch for the preparation of tailor-made starch-based ingredients and derivatives. Furthermore, the effect of treatment time, sample conditioning and ultrasound amplitude was studied. Ultrasonic treatment of cassava starch induced structural disorganization and microstructural changes evidenced mainly in the morphological characteristics of the granules and in their degrees of crystallinity. These structural modifications were supported by ATR-FTIR and SEM and CSLM studies as well as DRX and thermal analysis. The selection of the processing conditions is critical due to the complete gelatinization of the starch was produced with the maximum amplitude tested and without temperature control. Rheological dynamical analysis indicated changes at the molecular level in starch granules due to the ultrasound treated, revealing the paste stability under refrigeration condition. PCA allow to establish the interrelationships between microstructural and techno-functional properties. In summary, different starch derivatives could be obtained by adjusting the ultrasound treatment conditions depending on their potential applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Bio-insecticide Bacillus thuringiensis spores encapsulated with amaranth derivatized starches: studies on the propagation "in vitro".

PubMed

Rodríguez, Ana Priscila García; Martínez, Marcela Gaytán; Barrera-Cortés, Josefina; Ibarra, Jorge E; Bustos, Fernando Martínez

2015-02-01

Bacillus thuringiensis (Bt) is one of the bioinsecticides used worldwide due to its specific toxicity against target pests in their larval stage. Despite this advantage, its use is limited because of their short persistence in field when exposed to ultra violet light and changing environmental conditions. In this work, microencapsulation has been evaluated as a promising method to improve Bt activity. The objective of this study was to develop and characterize native and modified amaranth starch granules and evaluate their potential application as wall materials in the microcapsulation of B thuringiensis serovar kurstaki HD-1 (Bt- HD1), produced by spray drying. Native amaranth starch granules were treated by hydrolyzation, high energy milling (HEM) and were chemically modified by phosphorylation and succinylation. The size of the Bt microcapsules varied from 12.99 to 17.14 μm adequate to protect the spores of Bt from ultraviolet radiation. The aw coefficient of the microcapsules produced by the modified starches after drying was low (0.14-1.88), which prevent microbial growth. Microcapsules prepared with phosphorylated amaranth starch presented the highest bacterial count and active material yield. Different concentrations of the encapsulated Bt formulation in phosphorylated amaranth starch showed a high level of insecticidal activity when tested on M. sexta larvae and has great potential to be developed as a bioinsecticide formulation, also, the level of toxicity is much higher than that found in some of the products commercially available.

Development of photo-modified starch/kefiran/TiO2 bio-nanocomposite as an environmentally-friendly food packaging material.

PubMed

Goudarzi, Vahid; Shahabi-Ghahfarrokhi, Iman

2018-05-21

This paper reports on an experiment in which starch/kefiran/TiO 2 (SKT)-based bio-nanocomposite films were developed and modified by photo-chemical reaction. In so doing, film-forming solutions were exposed to ultraviolet A (UV-A) for different times (1, 6, and 12 h). The obtained results indicated that increasing UV-A exposure time brought about an increase (≈14.9%) in the tensile strength of bio-nanocomposites. However, elongation at break and Young's modulus of irradiated film specimen decreased (≈32%, ≈12%, respectively) by increasing UV-A exposure time, and the moisture-sensitive parameters of specimen decreased using UV-A irradiation. According to the results, the functional properties of irradiated bio-nanocomposite are depended on the ratio of cross-linkages between polymer chains and the potentially produced mono and disaccharide by UV-A. Copyright © 2018. Published by Elsevier B.V.

Effect of dry heating and ionic gum on the physicochemical and release properties of starch from Dioscorea.

PubMed

Vashisht, Deepika; Pandey, Anima; Hermenean, Anca; Yáñez-Gascón, Maria Josefa; Pérez-Sánchez, Horacio; Kumar, K Jayaram

2017-02-01

To meet the ever increasing industrial demand for excipients with desirable properties, modified starch is regarded as an alternative to it. With this in mind, the present study focuses on the modification of starches of Dioscorea from Jharkhand (India) using dry heat treatment with and without ionic gum. Modified starches were prepared using sodium alginate (1% w/w). Native and modified starches were subjected to heat treatment at 130°C for 2h and 4h. The effect of heating and ionic gum on the properties of Dioscorea starch was investigated. The amylose content, water holding capacity, micromeritic properties, swelling power, solubility and morphology of starches were evaluated. Dry heat treatment of starches without gum showed an increment in water-holding capacity after two-hours heating, but no such increment was found after four-hours heating. Oil binding capacity of starches modified with gum varied from 62% to 78%. Strongest effect of heat treatment occurred on the morphology of starches and thereby modified starches showed distorted surface morphology. Amylose content (21.09-21.89%) found to be decreased with the addition of gum which lead to decrease in paste clarity. Starches heated with gum at high-temperature resulted in restrict swelling and slight increase in solubility. Micromeritic properties of the modified starches showed the good flow properties. Further, the modified starches were investigated for in-vitro release studies and that the thermally modified derivatives can be a good prospect in slow release formulations. Copyright © 2016 Elsevier B.V. All rights reserved.

Starch-gum interactions: nutritional and technological implications.

PubMed

Sudhakar, V; Singhal, R S; Kulkarni, P R

1996-03-01

Starch contributes greatly to the textural properties of many foods. Starch, both native as well as various modified derivative forms offer a great scope to develop a variety of food products having varied texture and mouthfeel.

Preparation of low digestible and viscoelastic tigernut (Cyperus esculentus) starch by Bacillus acidopullulyticus pullulanase.

PubMed

Li, Xiaolei; Fu, Jingchao; Wang, Yujuan; Ma, Fumin; Li, Dan

2017-09-01

Tigernut starch is an underutilized food resource. In this study, pullulanase (PUL) hydrolysis was used to change its physiochemical properties for different food applications. The content of low digestible fractions, resistant starch and slow digestible starch, in PUL modified tigernut starch significantly increased from 2.03% to 25.08% (P<0.05) using 100U/g starch of PUL in the debranching reaction. The paste or dispersion of PUL modified tigernut starch had a significantly decreased viscoelasticity (P<0.05), but the paste still exhibited a typical property of pseudoplasticity. Molecular weight, amylopectin A B2 and B3 chain of PUL modified starch were lower, while amylose content, amylopectin B1 chain were higher than those of natural tigernut starch. The low digestible and viscous tigernut starch is highly valued as a component in some functional foods. Copyright © 2017 Elsevier B.V. All rights reserved.

Morphological and physicochemical characterization of porous starches obtained from different botanical sources and amylolytic enzymes.

PubMed

Benavent-Gil, Yaiza; Rosell, Cristina M

2017-10-01

Porous starches might offer an attractive alternative as bio-adsorbents of a variety of compounds. However, morphology and physicochemical properties of starches must be understood before exploring their applications. Objective was to study the action of different amylolytic enzymes for producing porous starches. Wheat, rice, potato and cassava starches were treated with Amyloglucosidase (AMG), α-amylase (AM) and cyclodextrin-glycosyltransferase (CGTase). Morphological characteristics, chemical composition, adsorptive capacity and pasting/thermal properties were assessed. Scanning Electron Microscopy (SEM) showed porous structures with diverse pore size distribution, which was dependent on the enzyme type and starch source, but no differences were observed in the total granule surface occupied by pores. The adsorptive capacity analysis revealed that modified starches had high water absorptive capacity and showed different oil adsorptive capacity depending on the enzyme type. Amylose content analysis revealed different hydrolysis pattern of the amylases, suggesting that AMG mainly affected crystalline region meanwhile AM and CGTase attacked amorphous area. A heatmap illustrated the diverse pasting properties of the different porous starches, which also showed significant different thermal properties, with different behavior between cereal and tuber starches. Therefore, it is possible to modulate the properties of starches through the use of different enzymes. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of amylose content and level of oxidation on the structural changes of acetylated corn starch and generation of free radicals.

PubMed

Pietrzyk, Sławomir; Fortuna, Teresa; Łabanowska, Maria; Juszczak, Lesław; Gałkowska, Dorota; Bączkowicz, Małgorzata; Kurdziel, Magdalena

2018-02-01

This study was aimed at determining the effect of starch oxidation on its acetylation, structure of starch granules, and generation of free radicals. Corn and waxy corn starches were oxidised by NaClO applied in doses of 10, 20, and 30g Cl/kg of starch, and then acetylated using acetic acid anhydride. The carboxyl, carbonyl, acetyl groups were determined in modified starches. Structural properties of starch granules were evaluated based on molecular weight distribution, gelatinisation, crystallinity, specific surface, intrinsic viscosity. EPR measurements were carried out to establish starch susceptibility to UV irradiation induced generation of free radicals. It was found that the number of carbon centered radicals was dependent on the kind of starch and its chemical modification. Study results allowed concluding that the applied modifications contributed to significant changes in starch granules that were determined not only by the amylose content of starch but also by the degree of its oxidation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antimicrobial paper based on a soy protein isolate or modified starch coating including carvacrol and cinnamaldehyde.

PubMed

Arfa, Afef Ben; Preziosi-Belloy, Laurence; Chalier, Pascale; Gontard, Nathalie

2007-03-21

Soy protein isolates (SPI) and octenyl-succinate (OSA) modified starch were used as paper coating and inclusion matrices of two antimicrobial compounds: cinnamaldehyde and carvacrol. Antimicrobial compound losses from the coated papers were evaluated after the coating and drying process, and the two matrices demonstrated retention ability that depended on the compound nature and concentration. Whereas carvacrol losses ranged between 12 and 45%, cinnamaldehyde losses varied from 43 to 76%. The losses were always higher from OSA-starch-coated papers than from SPI-coated papers. During storage in accelerated conditions, at 30 degrees C and 60% relative humidity, carvacrol retention from coated papers was found to be similar whatever the coating matrices and the carvacrol rate. In contrast, the retention from SPI-coated papers was particularly high for the cinnamaldehyde concentration of 30% (w/w) compared to the lowest (10% w/w) or highest concentration (60% w/w). Compared to carvacrol, faster release was observed, particurlarly when OSA-starch was used. The antimicrobial properties of the coated papers were shown against Escherichia coli and Botrytis cinerea and explained by favorable conditions of total release of the antimicrobial agents.

Acetylation and characterization of banana (Musa paradisiaca) starch.

PubMed

Bello-Pérez, L A; Contreras-Ramos, S M; Jìmenez-Aparicio, A; Paredes-López, O

2000-01-01

Banana native starch was acetylated and some of its functional properties were evaluated and compared to corn starch. In general, acetylated banana starch presented higher values in ash, protein and fat than corn acetylated starch. The modified starches had minor tendency to retrogradation assessed as % transmittance of starch pastes. At high temperature acetylated starches presented a water retention capacity similar to their native counterpart. The acetylation considerably increased the solubility of starches, and a similar behavior was found for swelling power. When freeze-thaw stability was studied, acetyl banana starch drained approximately 60% of water in the first and second cycles, but in the third and fourth cycles the percentage of separated water was low. However, acetyl corn starch showed lower freeze-thaw stability than the untreated sample. The modification increased the viscosity of banana starch pastes.

Design starch: stochastic modeling of starch granule biogenesis.

PubMed

Raguin, Adélaïde; Ebenhöh, Oliver

2017-08-15

Starch is the most widespread and abundant storage carbohydrate in plants and the main source of carbohydrate in the human diet. Owing to its remarkable properties and commercial applications, starch is still of growing interest. Its unique granular structure made of intercalated layers of amylopectin and amylose has been unraveled thanks to recent progress in microscopic imaging, but the origin of such periodicity is still under debate. Both amylose and amylopectin are made of linear chains of α-1,4-bound glucose residues, with branch points formed by α-1,6 linkages. The net difference in the distribution of chain lengths and the branching pattern of amylose (mainly linear), compared with amylopectin (racemose structure), leads to different physico-chemical properties. Amylose is an amorphous and soluble polysaccharide, whereas amylopectin is insoluble and exhibits a highly organized structure of densely packed double helices formed between neighboring linear chains. Contrarily to starch degradation that has been investigated since the early 20th century, starch production is still poorly understood. Most enzymes involved in starch growth (elongation, branching, debranching, and partial hydrolysis) are now identified. However, their specific action, their interplay (cooperative or competitive), and their kinetic properties are still largely unknown. After reviewing recent results on starch structure and starch growth and degradation enzymatic activity, we discuss recent results and current challenges for growing polysaccharides on granular surface. Finally, we highlight the importance of novel stochastic models to support the analysis of recent and complex experimental results, and to address how macroscopic properties emerge from enzymatic activity and structural rearrangements. © 2017 The Author(s).

Starch Applications for Delivery Systems

NASA Astrophysics Data System (ADS)

Li, Jason

2013-03-01

Starch is one of the most abundant and economical renewable biopolymers in nature. Starch molecules are high molecular weight polymers of D-glucose linked by α-(1,4) and α-(1,6) glycosidic bonds, forming linear (amylose) and branched (amylopectin) structures. Octenyl succinic anhydride modified starches (OSA-starch) are designed by carefully choosing a proper starch source, path and degree of modification. This enables emulsion and micro-encapsulation delivery systems for oil based flavors, micronutrients, fragrance, and pharmaceutical actives. A large percentage of flavors are encapsulated by spray drying in today's industry due to its high throughput. However, spray drying encapsulation faces constant challenges with retention of volatile compounds, oxidation of sensitive compound, and manufacturing yield. Specialty OSA-starches were developed suitable for the complex dynamics in spray drying and to provide high encapsulation efficiency and high microcapsule quality. The OSA starch surface activity, low viscosity and film forming capability contribute to high volatile retention and low active oxidation. OSA starches exhibit superior performance, especially in high solids and high oil load encapsulations compared with other hydrocolloids. The submission is based on research and development of Ingredion

Structures, properties, modifications, and uses of oat starch.

PubMed

Zhu, Fan

2017-08-15

There has been increasing interest to utilise oats and their components to formulate healthy food products. Starch is the major component of oat kernels and may account up to 60% of the dry weight. Starch properties may greatly determine the product quality. As a by-product of oat processing and fractionation, the starch may also be utilised for food and non-food applications. This mini-review updates the recent advances in the isolation, chemical and granular structures, physicochemical properties, chemical and physical modifications, and food and non-food uses of oat starch. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation and characterization of resistant starch III from elephant foot yam (Amorphophallus paeonifolius) starch.

PubMed

Reddy, Chagam Koteswara; Haripriya, Sundaramoorthy; Noor Mohamed, A; Suriya, M

2014-07-15

The purpose of this study was to assess the properties of resistant starch (RS) III prepared from elephant foot yam starch using pullulanase enzyme. Native and gelatinized starches were subjected to enzymatic hydrolysis (pullulanase, 40 U/g per 10h), autoclaved (121°C/30 min), stored under refrigeration (4°C/24h) and then lyophilized. After preparation of resistant starch III, the morphological, physical, chemical and functional properties were assessed. The enzymatic and retrogradation process increased the yield of resistant starch III from starch with a concomitant increase increase in its water absorption capacity and water solubility index. A decrease in swelling power was observed due to the hydrolysis and thermal process. Te reduced pasting properties and hardness of resistant starch III were associated with the disintegration of starch granules due to the thermal process. The viscosity was found to be inversely proportional to the RS content in the sample. The thermal properties of RS increased due to retrogradation and recrystallization (P<0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

Starch digestibility: past, present, and future.

PubMed

Bello-Perez, Luis A; Flores-Silva, Pamela C; Agama-Acevedo, Edith; Tovar, Juscelino

2018-02-10

In the last century, starch present in foods was considered to be completely digested. However, during the 1980s, studies on starch digestion started to show that besides digestible starch, which could be rapidly or slowly hydrolysed, there was a variable fraction that resisted hydrolysis by digestive enzymes. That fraction was named resistant starch (RS) and it encompasses those forms of starch that are not accessible to human digestive enzymes but can be fermented by the colonic microbiota, producing short-chain fatty acids. RS has been classified into five types, depending on the mechanism governing its resistance to enzymatic hydrolysis. Early research on RS was focused on the methods to determine its content in foods and its physiological effects, including fermentability in the large intestine. Later on, due to the interest of the food industry, methods to increase the RS content of isolated starches were developed. Nowadays, the influence of RS on the gut microbiota is a relevant research topic owing to its potential health-related benefits. This review summarizes over 30 years of investigation on starch digestibility, its relationship with human health, the methods to produce RS and its impact on the microbiome. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Comparison of various types of starch when used in meat sausages.

PubMed

Skrede, G

1989-01-01

Technological and sensory properties of meat sausages formulated with 4·0% of either potato flour, modified (acetylated distarch phosphate) potato starch, wheat, corn or tapioca starch were compared. Sausages were analyzed after cooking at temperatures between 65 and 85°C followed by storage at 5°C and -25°C. Characteristics evaluated were weight loss during cooking and storage, instrumentally and sensory assessed firmness, taste and smell of sausages. The results revealed differences in the suitability of starches for use in meat sausages. Part of the differences could be ascribed to differences in gelatination properties of the starches. With the criteria used for evaluating quality, potato flour was rated as the best suited starch followed by wheat starch while tapioca was rated as the least suited. Corn starch required cooking temperatures above 75°C and showed relatively low freeze/thaw stability. The modified potato starch stored well both above and below the freezing point. Copyright © 1989. Published by Elsevier Ltd.

Chemically modified graphite for electrochemical cells

DOEpatents

Greinke, R.A.; Lewis, I.C.

1998-05-26

This invention relates to chemically modified graphite particles: (a) that are useful in alkali metal-containing electrode of a electrochemical cell comprising: (1) the electrode, (2) a non-aqueous electrolytic solution comprising an organic aprotic solvent which solvent tends to decompose when the electrochemical cell is in use, and an electrically conductive salt of an alkali metal, and (3) a counter electrode; and (b) that are chemically modified with fluorine, chlorine, iodine or phosphorus to reduce such decomposition. This invention also relates to electrodes comprising such chemically modified graphite and a binder and to electrochemical cells containing such electrodes. 3 figs.

Chemically modified graphite for electrochemical cells

DOEpatents

Greinke, Ronald Alfred; Lewis, Irwin Charles

1998-01-01

This invention relates to chemically modified graphite particles: (a) that are useful in alkali metal-containing electrode of a electrochemical cell comprising: (i) the electrode, (ii) a non-aqueous electrolytic solution comprising an organic aprotic solvent which solvent tends to decompose when the electrochemical cell is in use, and an electrically conductive salt of an alkali metal, and (iii) a counterelectrode; and (b) that are chemically modified with fluorine, chlorine, iodine or phosphorus to reduce such decomposition. This invention also relates to electrodes comprising such chemically modified graphite and a binder and to electrochemical cells containing such electrodes.

Effect of heat-moisture treatment on the structural, physicochemical, and rheological characteristics of arrowroot starch.

PubMed

Pepe, Larissa S; Moraes, Jaqueline; Albano, Kivia M; Telis, Vânia R N; Franco, Célia M L

2016-04-01

The effect of heat-moisture treatment on structural, physicochemical, and rheological characteristics of arrowroot starch was investigated. Heat-moisture treatment was performed with starch samples conditioned to 28% moisture at 100 ℃ for 2, 4, 8, and 16 h. Structural and physicochemical characterization of native and modified starches, as well as rheological assays with gels of native and 4 h modified starches subjected to acid and sterilization stresses were performed. Arrowroot starch had 23.1% of amylose and a CA-type crystalline pattern that changed over the treatment time to A-type. Modified starches had higher pasting temperature and lower peak viscosity while breakdown viscosity practically disappeared, independently of the treatment time. Gelatinization temperature and crystallinity increased, while enthalpy, swelling power, and solubility decreased with the treatment. Gels from modified starches, independently of the stress conditions, were found to have more stable apparent viscosities and higher G' and G″ than gels from native starch. Heat-moisture treatment caused a reorganization of starch chains that increased molecular interactions. This increase resulted in higher paste stability and strengthened gels that showed higher resistance to shearing and heat, even after acid or sterilization conditions. A treatment time of 4 h was enough to deeply changing the physicochemical properties of starch. © The Author(s) 2015.

Mechanisms of starch digestion by α-amylase-Structural basis for kinetic properties.

PubMed

Dhital, Sushil; Warren, Frederick J; Butterworth, Peter J; Ellis, Peter R; Gidley, Michael J

2017-03-24

Recent studies of the mechanisms determining the rate and extent of starch digestion by α-amylase are reviewed in the light of current widely-used classifications for (a) the proportions of rapidly-digestible (RDS), slowly-digestible (SDS), and resistant starch (RS) based on in vitro digestibility, and (b) the types of resistant starch (RS 1,2,3,4…) based on physical and/or chemical form. Based on methodological advances and new mechanistic insights, it is proposed that both classification systems should be modified. Kinetic analysis of digestion profiles provides a robust set of parameters that should replace the classification of starch as a combination of RDS, SDS, and RS from a single enzyme digestion experiment. This should involve determination of the minimum number of kinetic processes needed to describe the full digestion profile, together with the proportion of starch involved in each process, and the kinetic properties of each process. The current classification of resistant starch types as RS1,2,3,4 should be replaced by one which recognizes the essential kinetic nature of RS (enzyme digestion rate vs. small intestinal passage rate), and that there are two fundamental origins for resistance based on (i) rate-determining access/binding of enzyme to substrate and (ii) rate-determining conversion of substrate to product once bound.

Process development of starch hydrolysis using mixing characteristics of Taylor vortices.

PubMed

Masuda, Hayato; Horie, Takafumi; Hubacz, Robert; Ohmura, Naoto; Shimoyamada, Makoto

2017-04-01

In food industries, enzymatic starch hydrolysis is an important process that consists of two steps: gelatinization and saccharification. One of the major difficulties in designing the starch hydrolysis process is the sharp change in its rheological properties. In this study, Taylor-Couette flow reactor was applied to continuous starch hydrolysis process. The concentration of reducing sugar produced via enzymatic hydrolysis was evaluated by varying operational variables: rotational speed of the inner cylinder, axial velocity (reaction time), amount of enzyme, and initial starch content in the slurry. When Taylor vortices were formed in the annular space, efficient hydrolysis occurred because Taylor vortices improved the mixing of gelatinized starch with enzyme. Furthermore, a modified inner cylinder was proposed, and its mixing performance was numerically investigated. The modified inner cylinder showed higher potential for enhanced mixing of gelatinized starch and the enzyme than the conventional cylinder.

Resistant starch: promise for improving human health.

PubMed

Birt, Diane F; Boylston, Terri; Hendrich, Suzanne; Jane, Jay-Lin; Hollis, James; Li, Li; McClelland, John; Moore, Samuel; Phillips, Gregory J; Rowling, Matthew; Schalinske, Kevin; Scott, M Paul; Whitley, Elizabeth M

2013-11-01

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research include identifying components of starch structure that confer digestion resistance, developing novel plants and starches, and modifying foods to incorporate these starches. Furthermore, recent and ongoing studies address the impact of digestion-resistant starches on the prevention and control of chronic human diseases, including diabetes, colon cancer, and obesity. This review provides a transdisciplinary overview of this field, including a description of types of resistant starches; factors in plants that affect digestion resistance; methods for starch analysis; challenges in developing food products with resistant starches; mammalian intestinal and gut bacterial metabolism; potential effects on gut microbiota; and impacts and mechanisms for the prevention and control of colon cancer, diabetes, and obesity. Although this has been an active area of research and considerable progress has been made, many questions regarding how to best use digestion-resistant starches in human diets for disease prevention must be answered before the full potential of resistant starches can be realized.

Polyethylene glycol modified, cross-linked starch-coated iron oxide nanoparticles for enhanced magnetic tumor targeting.

PubMed

Cole, Adam J; David, Allan E; Wang, Jianxin; Galbán, Craig J; Hill, Hannah L; Yang, Victor C

2011-03-01

While successful magnetic tumor targeting of iron oxide nanoparticles has been achieved in a number of models, the rapid blood clearance of magnetically suitable particles by the reticuloendothelial system (RES) limits their availability for targeting. This work aimed to develop a long-circulating magnetic iron oxide nanoparticle (MNP) platform capable of sustained tumor exposure via the circulation and, thus, potentially enhanced magnetic tumor targeting. Aminated, cross-linked starch (DN) and aminosilane (A) coated MNPs were successfully modified with 5 kDa (A5, D5) or 20 kDa (A20, D20) polyethylene glycol (PEG) chains using simple N-Hydroxysuccinimide (NHS) chemistry and characterized. Identical PEG-weight analogues between platforms (A5 & D5, A20 & D20) were similar in size (140-190 nm) and relative PEG labeling (1.5% of surface amines - A5/D5, 0.4% - A20/D20), with all PEG-MNPs possessing magnetization properties suitable for magnetic targeting. Candidate PEG-MNPs were studied in RES simulations in vitro to predict long-circulating character. D5 and D20 performed best showing sustained size stability in cell culture medium at 37 °C and 7 (D20) to 10 (D5) fold less uptake in RAW264.7 macrophages when compared to previously targeted, unmodified starch MNPs (D). Observations in vitro were validated in vivo, with D5 (7.29 h) and D20 (11.75 h) showing much longer half-lives than D (0.12 h). Improved plasma stability enhanced tumor MNP exposure 100 (D5) to 150 (D20) fold as measured by plasma AUC(0-∞). Sustained tumor exposure over 24 h was visually confirmed in a 9L-glioma rat model (12 mg Fe/kg) using magnetic resonance imaging (MRI). Findings indicate that a polyethylene glycol modified, cross-linked starch-coated MNP is a promising platform for enhanced magnetic tumor targeting, warranting further study in tumor models. Copyright © 2010 Elsevier Ltd. All rights reserved.

Partial characterization of chayotextle starch-based films added with ascorbic acid encapsulated in resistant starch.

PubMed

Martínez-Ortiz, Miguel A; Vargas-Torres, Apolonio; Román-Gutiérrez, Alma D; Chavarría-Hernández, Norberto; Zamudio-Flores, Paul B; Meza-Nieto, Martín; Palma-Rodríguez, Heidi M

2017-05-01

Chayotextle starch was modified by subjecting it to a dual treatment with acid and heating-cooling cycles. This caused a decrease in the content of amylose, which showed values of 30.22%, 4.80%, 3.27% and 3.57% for native chayotextle starch (NCS), starch modified by acid hydrolysis (CMS), and CMS with one (CMS1AC) and three autoclave cycles (CMS3AC), respectively. The percentage of crystallinity showed an increase of 36.9%-62% for NCS and CMS3AC. The highest content of resistant starch (RS) was observed in CMS3AC (37.05%). The microcapsules were made with CMS3AC due to its higher RS content; the total content of ascorbic acid of the microcapsules was 82.3%. The addition of different concentrations of CMS3AC microcapsules (0%, 2.5%, 6.255% and 12.5%) to chayotextle starch-based films (CSF) increased their tensile strength and elastic modulus. The content of ascorbic acid and RS in CSF was ranged from 0% to 59.4% and from 4.84% to 37.05% in the control film and in the film mixed with CMS3AC microcapsules, respectively. Water vapor permeability (WVP) values decreased with increasing concentrations of microcapsules in the films. Microscopy observations showed that higher concentrations of microcapsules caused agglomerations due their poor distribution in the matrix of the films. Copyright © 2017 Elsevier B.V. All rights reserved.

Optimization of factors to obtain cassava starch films with improved mechanical properties

NASA Astrophysics Data System (ADS)

Monteiro, Mayra; Oliveira, Victor; Santos, Francisco; Barros Neto, Eduardo; Silva, Karyn; Silva, Rayane; Henrique, João; Chibério, Abimaelle

2017-08-01

In this study, was investigated the optimization of the factors that significantly influenced the mechanical property improvement of cassava starch films through complete factorial design 23. The factors to be analyzed were cassava starch, glycerol and modified clay contents. A regression model was proposed by the factorial analysis, aiming to estimate the condition of the individual factors investigated in the optimum state of the mechanical properties of the biofilm, using the following statistical tool: desirability function and response surface. The response variable that delimits the improvement of the mechanical property of the biofilm is the tensile strength, such improvement is obtained by maximizing the response variable. The factorial analysis showed that the best combination of factor configurations to reach the best response was found to be: with 5g of cassava starch, 10% of glycerol and 5% of modified clay, both percentages in relation to the dry mass of starch used. In addition, the starch biofilm showing the lowest response contained 2g of cassava starch, 0% of modified clay and 30% of glycerol, and was consequently considered the worst biofilm.

Enzymatically modified starch up-regulates expression of incretins and sodium-coupled monocarboxylate transporter in jejunum of growing pigs.

PubMed

Metzler-Zebeli, B U; Ertl, R; Grüll, D; Molnar, T; Zebeli, Q

2017-07-01

Dietary effects on the host are mediated via modulation of the intestinal mucosal responses. The present study investigated the effect of an enzymatically modified starch (EMS) product on the mucosal expression of genes related to starch digestion, sugar and short-chain fatty acid (SCFA) absorption and incretins in the jejunum and cecum in growing pigs. Moreover, the impact of the EMS on hepatic expression of genes related to glucose and lipid metabolism, and postprandial serum metabolites were assessed. Barrows (n=12/diet; initial BW 29 kg) were individually fed three times daily with free access to a diet containing either EMS or waxy corn starch as control (CON) for 10 days. The enzymatic modification led to twice as many α-1,6-glycosidic bonds (~8%) in the amylopectin fraction in the EMS in comparison with the non-modified native waxy corn starch (4% α-1,6-glycosidic bonds). Linear discriminant analysis revealed distinct clustering of mucosal gene expression for EMS and CON diets in jejunum. Compared with the CON diet, the EMS intake up-regulated jejunal expression of sodium-coupled monocarboxylate transporter (SMCT), glucagon-like peptide-1 (GLP1) and gastric inhibitory polypeptide (GIP) (P<0.05) and intestinal alkaline phosphatase (ALPI) (P=0.08), which may be related to greater luminal SCFA availability, whereas cecal gene expression was unaffected by diet. Hepatic peroxisome proliferator-activated receptor γ (PPARγ) expression tended (P=0.07) to be down-regulated in pigs fed the EMS diet compared with pigs fed the CON diet, which may explain the trend (P=0.08) of 30% decrease in serum triglycerides in pigs fed the EMS diet. Furthermore, pigs fed the EMS diet had a 50% higher (P=0.03) serum urea concentration than pigs fed the CON diet potentially indicating an increased use of glucogenic amino acids for energy acquisition in these pigs. Present findings suggested the jejunum as the target site to influence the intestinal epithelium and altered lipid and

Statistical analysis of the factors that influenced the mechanical properties improvement of cassava starch films

NASA Astrophysics Data System (ADS)

Monteiro, Mayra; Oliveira, Victor; Santos, Francisco; Barros Neto, Eduardo; Silva, Karyn; Silva, Rayane; Henrique, João; Chibério, Abimaelle

2017-08-01

In order to obtain cassava starch films with improved mechanical properties in relation to the synthetic polymer in the packaging production, a complete factorial design 23 was carried out in order to investigate which factor significantly influences the tensile strength of the biofilm. The factors to be investigated were cassava starch, glycerol and modified clay contents. Modified bentonite clay was used as a filling material of the biofilm. Glycerol was the plasticizer used to thermoplastify cassava starch. The factorial analysis suggested a regression model capable of predicting the optimal mechanical property of the cassava starch film from the maximization of the tensile strength. The reliability of the regression model was tested by the correlation established with the experimental data through the following statistical analyse: Pareto graph. The modified clay was the factor of greater statistical significance on the observed response variable, being the factor that contributed most to the improvement of the mechanical property of the starch film. The factorial experiments showed that the interaction of glycerol with both modified clay and cassava starch was significant for the reduction of biofilm ductility. Modified clay and cassava starch contributed to the maximization of biofilm ductility, while glycerol contributed to the minimization.

Allelic variants of the amylose extender mutation of maize demonstrate phenotypic variation in starch structure resulting from modified protein–protein interactions

PubMed Central

Liu, Fushan; Ahmed, Zaheer; Lee, Elizabeth A.; Donner, Elizabeth; Liu, Qiang; Ahmed, Regina; Morell, Matthew K.; Emes, Michael J.; Tetlow, Ian J.

2012-01-01

amylose extender (ae−) starches characteristically have modified starch granule morphology resulting from amylopectin with reduced branch frequency and longer glucan chains in clusters, caused by the loss of activity of the major starch branching enzyme (SBE), which in maize endosperm is SBEIIb. A recent study with ae− maize lacking the SBEIIb protein (termed ae1.1 herein) showed that novel protein–protein interactions between enzymes of starch biosynthesis in the amyloplast could explain the starch phenotype of the ae1.1 mutant. The present study examined an allelic variant of the ae− mutation, ae1.2, which expresses a catalytically inactive form of SBEIIb. The catalytically inactive SBEIIb in ae1.2 lacks a 28 amino acid peptide (Val272–Pro299) and is unable to bind to amylopectin. Analysis of starch from ae1.2 revealed altered granule morphology and physicochemical characteristics distinct from those of the ae1.1 mutant as well as the wild-type, including altered apparent amylose content and gelatinization properties. Starch from ae1.2 had fewer intermediate length glucan chains (degree of polymerization 16–20) than ae1.1. Biochemical analysis of ae1.2 showed that there were differences in the organization and assembly of protein complexes of starch biosynthetic enzymes in comparison with ae1.1 (and wild-type) amyloplasts, which were also reflected in the composition of starch granule-bound proteins. The formation of stromal protein complexes in the wild-type and ae1.2 was strongly enhanced by ATP, and broken by phosphatase treatment, indicating a role for protein phosphorylation in their assembly. Labelling experiments with [γ-32P]ATP showed that the inactive form of SBEIIb in ae1.2 was phosphorylated, both in the monomeric form and in association with starch synthase isoforms. Although the inactive SBEIIb was unable to bind starch directly, it was strongly associated with the starch granule, reinforcing the conclusion that its presence in the

Application of ultra high pressure (UHP) in starch chemistry.

PubMed

Kim, Hyun-Seok; Kim, Byung-Yong; Baik, Moo-Yeol

2012-01-01

Ultra high pressure (UHP) processing is an attractive non-thermal technique for food treatment and preservation at room temperature, with the potential to achieve interesting functional effects. The majority of UHP process applications in food systems have focused on shelf-life extension associated with non-thermal sterilization and a reduction or increase in enzymatic activity. Only a few studies have investigated modifications of structural characteristics and/or protein functionalities. Despite the rapid expansion of UHP applications in food systems, limited information is available on the effects of UHP on the structural and physicochemical properties of starch and/or its chemical derivatives included in most processed foods as major ingredients or minor additives. Starch and its chemical derivatives are responsible for textural and physical properties of food systems, impacting their end-use quality and/or shelf-life. This article reviews UHP processes for native (unmodified) starch granules and their effects on the physicochemical properties of UHP-treated starch. Furthermore, functional roles of UHP in acid-hydrolysis, hydroxypropylation, acetylation, and cross-linking reactions of starch granules, as well as the physicochemical properties of UHP-assisted starch chemical derivatives, are discussed.

Modification of cassava starch using combination process lactic acid hydrolysis and micro wave heating to increase coated peanut expansion quality

NASA Astrophysics Data System (ADS)

Sumardiono, Siswo; Pudjihastuti, Isti; Jos, Bakti; Taufani, Muhammad; Yahya, Faad

2017-05-01

Modified cassava starch is very prospective products in the food industry. The main consideration of this study is the increasing volume of imported wheat and the demand for modified cassava starch industry. The purpose of this study is the assessing of lactic acid hydrolysis and microwave heating impact to the physicochemical and rheological properties of modified cassava starch, and test applications of modified cassava starch to coated peanut expansion quality. Experimental variables include the concentration of lactic acid (0.5% w/w, 1% w/w; 2% w/w), a time of hydrolysis (15, 30, 45 minutes), a time of microwave heating (1, 2, 3 hours). The research step is by dissolving lactic acid using aquadest in the stirred tank reactor, then added cassava starch. Hydrolysed cassava starch was then heated by microwave. Physicochemical properties and rheology of the modified cassava starch is determined by the solubility, swelling power, and test congestion. The optimum obtained results indicate that solubility, swelling power, congestion test, respectively for 19.75%; 24.25% and 826.10% in the hydrolysis treatment for 15 minutes, 1% w lactic acid and microwave heating 3 hours. The physicochemical and rheological properties of modified cassava starch have changed significantly when compared to the native cassava starch. Furthermore, these modified cassava starch are expected to be used for the substitution of food products.

Chemically modified carbonic anhydrases useful in carbon capture systems

DOEpatents

Novick, Scott; Alvizo, Oscar

2013-01-15

The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

Chemically modified carbonic anhydrases useful in carbon capture systems

DOEpatents

Novick, Scott J; Alvizo, Oscar

2013-10-29

The present disclosure relates to chemically modified carbonic anhydrase polypeptides and soluble compositions, homogenous liquid formulations comprising them. The chemically modified carbonic anhydrase polypeptides have improved properties relative to the same carbonic anhydrase polypeptide that is not chemically modified including the improved properties of increased activity and/or stability in the presence of amine compounds, ammonia, or carbonate ion. The present disclosure also provides methods of preparing the chemically modified polypeptides and methods of using the chemically modified polypeptides for accelerating the absorption of carbon dioxide from a gas stream into a solution as well as for the release of the absorbed carbon dioxide for further treatment and/or sequestering.

Ionic liquids as novel solvents for biosynthesis of octenyl succinic anhydride-modified waxy maize starch.

PubMed

Li, Dandan; Zhang, Xiwen; Tian, Yaoqi

2016-05-01

Biosynthesis of octenyl succinic anhydride (OSA) starch was investigated using ionic liquids (ILs) as reaction media. Waxy maize starch was pretreated in 1-butyl-3-methylimidazolium chlorine and then esterified with OSA in 1-octyl-3-methylimidazolium nitrate by using Novozyme 435 as catalyst. The degree of substitution of OSA starch reached 0.0130 with 5 wt% starch concentration and 1 wt% lipase dosage based on ILs weight at 50 °C for 3h. The formation of OSA starch was confirmed by fourier transform infrared spectroscopy. Scanning electron microscopy and X-ray diffraction revealed that the morphology and crystal structure of starch were significantly destroyed. Thermogravimetric analysis showed that esterification decreased the thermal stability of starch. The successful lipase-catalyzed synthesis of OSA starch in ILs suggests that ILs are potential replacement of traditional organic solvents for starch ester biosynthesis. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis and characterization of modified starch/polybutadiene as novel transdermal drug delivery system.

PubMed

Saboktakin, Mohammad Reza; Akhyari, Shahab; Nasirov, Fizuli A

2014-08-01

Transdermal drug delivery systems are topically administered medicaments in the form of patches that deliver drugs for systemic effects at a predetermined and controlled rate. It works very simply in which drug is applied inside the patch and it is worn on skin for long period of time. Polymer matrix, drug, permeation enhancers are the main components of transdermal drug delivery systems. The objective of the present study was to develop the modified starch and 1,4-cis polybutadiene nanoparticles as novel polymer matrix system. We have been studied the properties of a novel transdermal drug delivery system with clonidine as drug model. Copyright © 2014 Elsevier B.V. All rights reserved.

Resistant Starch but Not Enzymatically Modified Waxy Maize Delays Development of Diabetes in Zucker Diabetic Fatty Rats.

PubMed

Hedemann, Mette Skou; Hermansen, Kjeld; Pedersen, Sven; Bach Knudsen, Knud Erik

2017-05-01

Background: The incidence of type 2 diabetes (T2D) is increasing worldwide, and nutritional management of circulating glucose may be a strategic tool in the prevention of T2D. Objective: We studied whether enzymatically modified waxy maize with an increased degree of branching delayed the onset of diabetes in male Zucker diabetic fatty (ZDF) rats. Methods: Forty-eight male ZDF rats, aged 5 wk, were divided into 4 groups and fed experimental diets for 9 wk that contained 52.95% starch: gelatinized corn starch (S), glucidex (GLU), resistant starch (RS), or enzymatically modified starch (EMS). Blood glucose after feed deprivation was assessed every second week; blood samples taken at run-in and at the end of the experiment were analyzed for glycated hemoglobin (HbA1c) and plasma glucose, insulin, and lipids. During weeks 2 and 8, urine was collected for metabolomic analysis. Results: Based on blood glucose concentrations in feed-deprived rats, none of the groups developed diabetes. However, in week 9, plasma glucose after feed deprivation was significantly lower in rats fed the S and RS diets (13.5 mmol/L) than in rats fed the GLU and EMS diets (17.0-18.9 mmol/L), and rats fed RS had lower HbA1c (4.9%) than rats fed the S, GLU, and EMS (5.6-6.1%) diets. The homeostasis model assessment of insulin resistance was significantly lower in rats fed RS than in rats fed the other diets (185 compared with 311-360), indicating that rats fed the S, GLU, and EMS diets were diabetic, and a 100% higher urine excretion during week 8 in rats fed the GLU and EMS diets than that of rats fed S and RS showed that they were diabetic. Urinary nontargeted metabolomics revealed that the diabetic state of rats fed S, GLU, and EMS diets influenced microbial metabolism, as well as amino acid, lipid, and vitamin metabolism. Conclusions: EMS did not delay the onset of diabetes in ZDF rats, whereas rats fed RS showed no signs of diabetes. © 2017 American Society for Nutrition.

THE RESEARCH ON THERMAL PROPERTIES AND HYDROPHOBILITY OF THE NATIVE STARCH/HYDROLYSIS STARCH BLENDS WITH TREATED CaCO{sub 3} POWDER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, C.-I; Huang, C.-Y.

In this research, hydrolysis starch was added into the starch blends to study the thermal properties. The enthalpy of blends had a significant decrease to 109J/g as content of treated CaCO{sub 3} increased to 5wt%. The modified starch was degraded slightly to produce glucose in the hydrolysis treatment. The amount of glucose in native starch and hydrolysis starch was 0.09 {mu}mol and 0.14 {mu}mol by the DNS measurement. Moreover, CaCO{sub 3} treated with titanium coupling agent was also added to improve miscibility and hydrophobility in the starch blends. The contact angle of the blends increased from 60 deg. to 95more » deg. when 15wt% treated CaCO{sub 3} was added. Treated CaCO{sub 3} was confirmed to improve the hydrophobility of starch blends effectively.« less

PROTEIN TARGETING TO STARCH Is Required for Localising GRANULE-BOUND STARCH SYNTHASE to Starch Granules and for Normal Amylose Synthesis in Arabidopsis

PubMed Central

Seung, David; Soyk, Sebastian; Coiro, Mario; Maier, Benjamin A.; Eicke, Simona; Zeeman, Samuel C.

2015-01-01

The domestication of starch crops underpinned the development of human civilisation, yet we still do not fully understand how plants make starch. Starch is composed of glucose polymers that are branched (amylopectin) or linear (amylose). The amount of amylose strongly influences the physico-chemical behaviour of starchy foods during cooking and of starch mixtures in non-food manufacturing processes. The GRANULE-BOUND STARCH SYNTHASE (GBSS) is the glucosyltransferase specifically responsible for elongating amylose polymers and was the only protein known to be required for its biosynthesis. Here, we demonstrate that PROTEIN TARGETING TO STARCH (PTST) is also specifically required for amylose synthesis in Arabidopsis. PTST is a plastidial protein possessing an N-terminal coiled coil domain and a C-terminal carbohydrate binding module (CBM). We discovered that Arabidopsis ptst mutants synthesise amylose-free starch and are phenotypically similar to mutants lacking GBSS. Analysis of granule-bound proteins showed a dramatic reduction of GBSS protein in ptst mutant starch granules. Pull-down assays with recombinant proteins in vitro, as well as immunoprecipitation assays in planta, revealed that GBSS physically interacts with PTST via a coiled coil. Furthermore, we show that the CBM domain of PTST, which mediates its interaction with starch granules, is also required for correct GBSS localisation. Fluorescently tagged Arabidopsis GBSS, expressed either in tobacco or Arabidopsis leaves, required the presence of Arabidopsis PTST to localise to starch granules. Mutation of the CBM of PTST caused GBSS to remain in the plastid stroma. PTST fulfils a previously unknown function in targeting GBSS to starch. This sheds new light on the importance of targeting biosynthetic enzymes to sub-cellular sites where their action is required. Importantly, PTST represents a promising new gene target for the biotechnological modification of starch composition, as it is exclusively involved

Resistant Starch: Promise for Improving Human Health12

PubMed Central

Birt, Diane F.; Boylston, Terri; Hendrich, Suzanne; Jane, Jay-Lin; Hollis, James; Li, Li; McClelland, John; Moore, Samuel; Phillips, Gregory J.; Rowling, Matthew; Schalinske, Kevin; Scott, M. Paul; Whitley, Elizabeth M.

2013-01-01

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research include identifying components of starch structure that confer digestion resistance, developing novel plants and starches, and modifying foods to incorporate these starches. Furthermore, recent and ongoing studies address the impact of digestion-resistant starches on the prevention and control of chronic human diseases, including diabetes, colon cancer, and obesity. This review provides a transdisciplinary overview of this field, including a description of types of resistant starches; factors in plants that affect digestion resistance; methods for starch analysis; challenges in developing food products with resistant starches; mammalian intestinal and gut bacterial metabolism; potential effects on gut microbiota; and impacts and mechanisms for the prevention and control of colon cancer, diabetes, and obesity. Although this has been an active area of research and considerable progress has been made, many questions regarding how to best use digestion-resistant starches in human diets for disease prevention must be answered before the full potential of resistant starches can be realized. PMID:24228189

Resistant starch: a functional food that prevents DNA damage and chemical carcinogenesis.

PubMed

Navarro, S D; Mauro, M O; Pesarini, J R; Ogo, F M; Oliveira, R J

2015-03-06

Resistant starch is formed from starch and its degradation products and is not digested or absorbed in the intestine; thus, it is characterized as a fiber. Because fiber intake is associated with the prevention of DNA damage and cancer, the potential antigenotoxic, antimutagenic, and anticarcinogenic capabilities of resistant starch from green banana flour were evaluated. Animals were treated with 1,2-dimethylhydrazine and their diet was supplemented with 10% green banana flour according to the following resistant starch protocols: pretreatment, simultaneous treatment, post-treatment, and pre + continuous treatment. The results demonstrated that resistant starch is not genotoxic, mutagenic, or carcinogenic. The results suggest that resistant starch acts through desmutagenesis and bio-antimutagenesis, as well as by reducing aberrant crypt foci, thereby improving disease prognosis. These findings imply that green banana flour has therapeutic properties that should be explored for human dietary applications.

Agro-industrial residue from starch extraction of Pachyrhizus ahipa as filler of thermoplastic corn starch films.

PubMed

López, O V; Versino, F; Villar, M A; García, M A

2015-12-10

Biocomposites films based on thermoplastic corn starch (TPS) containing 0.5% w/w fibrous residue from Pachyrhizus ahipa starch extraction (PASR) were obtained by melt-mixing and compression molding. PASR is mainly constituted by remaining cell walls and natural fibers, revealed by Scanning Electron Microscopy (SEM). Chemical composition of the residue indicated that fiber and starch were the principal components. Biocomposites thermo-stability was determined by Thermo-Gravimetric Analysis. A continuous PASR-TPS interface was observed by SEM, as a result of a good adhesion of the fibrous residue to starch matrix. Likewise, films containing PASR presented fewer superficial cracks than TPS ones, whereas their fracture surfaces were more irregular. Besides, the presence of PASR increased starch films roughness, due to fibers agglomerates. Films reinforced with PASR showed significantly lower water vapor permeability (WVP). In addition, PARS filler increased maximum tensile strength and Young's modulus of TPS films, thus leading to more resistant starch matrixes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Resistant starch in food: a review.

PubMed

Raigond, Pinky; Ezekiel, Rajarathnam; Raigond, Baswaraj

2015-08-15

The nutritional property of starch is related to its rate and extent of digestion and absorption in the small intestine. For nutritional purposes, starch is classified as rapidly available, slowly available and resistant starch (RS). The exact underlying mechanism of relative resistance of starch granules is complicated because those factors are often interconnected. The content of RS in food is highly influenced by food preparation manner and processing techniques. Physical or chemical treatments also alter the level of RS in a food. Commercial preparations of RS are now available and can be added to foods as an ingredient for lowering the calorific value and improving textural and organoleptic characteristics along with increasing the amount of dietary fiber. RS has assumed great importance owing to its unique functional properties and health benefits. The beneficial effects of RS include glycemic control and control of fasting plasma triglyceride and cholesterol levels and absorption of minerals. This review attempts to analyze the information published, especially in the recent past, on classification, structure, properties, applications and health benefits of RS. © 2014 Society of Chemical Industry.

Quinoa starch granules as stabilizing particles for production of Pickering emulsions.

PubMed

Rayner, Marilyn; Sjöö, Malin; Timgren, Anna; Dejmek, Petr

2012-01-01

Intact starch granules isolated from quinoa (Chenopodium quinoa Willd.) were used to stabilize emulsion drops in so-called Pickering emulsions. Miglyol 812 was used as dispersed phase and a phosphate buffer (pH7) with different salt (NaCl) concentrations was used as the continuous phase. The starch granules were hydrophobically modified to different degrees by octenyl succinic anhydride (OSA) or by dry heat treatment at 120 degrees C in order to study the effect on the resulting emulsion drop size. The degree of OSA-modification had a low to moderate impact on drop size. The highest level of modification (4.66%) showed the largest mean drop size, and lowest amount of free starch, which could be an effect of a higher degree of aggregation of the starch granules and, thereby, also the emulsion drops stabilized by them. The heat treated starch granules had a poor stabilizing ability and only the starch heated for the longest time (150 min at 120 degrees C) had a better emulsifying capacity than the un-modified native starch granules. The effect of salt concentration was rather limited. However, an increased concentration of salt slightly increased the mean drop size and the elastic modulus.

Study on the synthesis and physicochemical properties of starch acetate with low substitution under microwave assistance.

PubMed

Lin, Derong; Zhou, Wei; Zhao, Jingjing; Lan, Weijie; Chen, Rongming; Li, Yutong; Xing, Baoshan; Li, Zhuohao; Xiao, Mengshi; Wu, Zhijun; Li, Xindan; Chen, Rongna; Zhang, Xingwen; Chen, Hong; Zhang, Qing; Qin, Wen; Li, Suqing

2017-10-01

In this study, synthesis and physicochemical properties of starch acetate with low substitution under microwave were studied. A three-level-three-factorial Central Composite Design using Response Surface Methodology (RSM) was employed to optimize the reaction conditions. The optimal parameters are as follows: amount of acetic anhydride of 12%, radiation time of 11min, and microwave power of 100W. These optimal conditions predicted by RSM were confirmed that the degree of substitution (DS) of acetate starch is 0.0691mg/g and the physical and chemical properties of natural corn starch (NCS) and corn starch acetate (ACS) were further studied.The transparency, water separation, water absorption, expansion force, and solubility of ACS low substitution are better than NCS, while the NCS's hydrolysis percentage is higher than ACS, which indicate that the modified corn starch has better performance than native corn starch. The surface morphology of the corn starch acetate was examined by scanning electron microscope (SEM), which showed that it had a smooth surface and a spherical and polygonal shape. However, samples' shape is irregular. Crystal structure was observed by X-ray diffraction, and the ACS can determine the level of microwave technology that can destroy the extent of the crystal and amorphous regions. Fourier transform infrared (FTIR) spectroscopy shows that around 1750cm -1 carbonyl signal determines acetylation bonding successfully. Copyright © 2017 Elsevier B.V. All rights reserved.

[Adsorption of phenol chemicals by surfactant-modified zeolites].

PubMed

Xie, Jie; Wang, Zhe; Wu, De-Yi; Li, Chun-Jie

2012-12-01

Two kinds of zeolites were prepared from fly ash and modified by surfactant subsequently. Surfactant-modified zeolites were studied for adsorption of phenol chemicals (phenol, p-chlorphenol, bisphenol A). It showed that the adsorption affinity of zeolite to phenol chemicals was significantly improved after surfactant modification. The adsorption isotherms of phenol chemicals were well fitted by the Langmuir isotherm. For the two surfactant-surfactant modified zeolites, the maximum adsorption amounts of phenol, p-chlorphenol, and bisphenol A calculated from the Langmuir equation were 37.7, 52.36, 90.9 mg x g(-1) and 10.7, 22.83, 56.8 mg x g(-1), respectively. When pH values of solutions were higher than the pK(a) values of phenol chemicals, the removal efficiencies were getting higher with the increase of pH values. The octanol/water partition coefficient (K(ow)) was also found to be an important factor affecting adsorption of phenol chemicals by the modified zeolites. Higher K(ow) value, which means the greater hydrophobicity of the chemicals, resulted in a higher removal.

The physicochemical properties of a spray dried glutinous rice starch biopolymer.

PubMed

Laovachirasuwan, Pornpun; Peerapattana, Jomjai; Srijesdaruk, Voranuch; Chitropas, Padungkwan; Otsuka, Makoto

2010-06-15

Glutinous rice starch (GRS) is a biopolymer used widely in the food industry but not at all in the pharmaceutical industry. There are several ways to modify this biopolymer. Physical modification is simple and cheap because it requires no chemicals or biological agents. The aim of this study was to characterize the physicochemical properties of a spray dried glutinous rice starch (SGRS) produced from pregelatinized GRS. The surface morphology changed from an irregular to concave spherical shape as revealed by Scanning Electron Microscopy (SEM). SGRS was almost amorphous as determined by X-ray Diffraction (XRD) spectroscopy. The water molecules became linked through hydrogen bonds to the exposed hydroxyl group of amorphous SGRS as determined by Near Infrared (NIR) spectroscopy. Then, SGRS formed a colloid gel matrix with water and developed a highly viscous gelatinous form as determined using Differential Scanning Calorimetry (DSC) and a stress control type rheometer. In addition, SGRS can swell and produce a gelatinous surface barrier like a hydrophilic matrix biopolymer which controls drug release. Therefore, a novel application of SGRS is as a sustained release modifier for direct compression tablets in the pharmaceutical industry. Copyright 2010 Elsevier B.V. All rights reserved.

Starch-assisted synthesis and optical properties of ZnS nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tian, Xiuying, E-mail: xiuyingt@yahoo.com; Wen, Jin; Wang, Shumei

Highlights: • ZnS spherical nanostructure was prepared via starch-assisted method. • The crystalline lattice structure, morphologies, chemical and optical properties of ZnS nanoparticles. • The forming mechanism of ZnS nanoparticles. • ZnS spherical nano-structure can show blue emission at 460–500 nm. - Abstract: ZnS nanoparticles are fabricated via starch-assisted method. The effects of different starch amounts on structure and properties of samples are investigated, and the forming mechanism of ZnS nanoparticles is discussed. By X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–vis)more » spectroscopy and fluorescence (FL) spectrometer, their phases, crystalline lattice structure, morphologies, chemical and optical properties are characterized. The results show that ZnS has polycrystalline spherical structure with the mean diameter of 130 nm. Sample without starch reveals irregular aggregates with particle size distribution of 0.5–2 μm. The band gap value of ZnS is 3.97 eV. The chemical interaction exists between starch molecules and ZnS nanoparticles by hydrogen bonds. The stronger FL emission peaks of ZnS synthesized with starch, indicate a larger content of sulfur vacancies or defects than ZnS synthesized without starch.« less

Starch phosphorylation in potato tubers is influenced by allelic variation in the genes encoding glucan water dikinase, starch branching enzymes I and II, and starch synthase III

PubMed Central

Carpenter, Margaret A.; Joyce, Nigel I.; Genet, Russell A.; Cooper, Rebecca D.; Murray, Sarah R.; Noble, Alasdair D.; Butler, Ruth C.; Timmerman-Vaughan, Gail M.

2015-01-01

Starch phosphorylation is an important aspect of plant metabolism due to its role in starch degradation. Moreover, the degree of phosphorylation of starch determines its physicochemical properties and is therefore relevant for industrial uses of starch. Currently, starch is chemically phosphorylated to increase viscosity and paste stability. Potato cultivars with elevated starch phosphorylation would make this process unnecessary, thereby bestowing economic and environmental benefits. Starch phosphorylation is a complex trait which has been previously shown by antisense gene repression to be influenced by a number of genes including those involved in starch synthesis and degradation. We have used an association mapping approach to discover genetic markers associated with the degree of starch phosphorylation. A diverse collection of 193 potato lines was grown in replicated field trials, and the levels of starch phosphorylation at the C6 and C3 positions of the glucosyl residues were determined by mass spectrometry of hydrolyzed starch from tubers. In addition, the potato lines were genotyped by amplicon sequencing and microsatellite analysis, focusing on candidate genes known to be involved in starch synthesis. As potato is an autotetraploid, genotyping included determination of allele dosage. Significant associations (p < 0.001) were found with SNPs in the glucan water dikinase (GWD), starch branching enzyme I (SBEI) and the starch synthase III (SSIII) genes, and with a SSR allele in the SBEII gene. SNPs in the GWD gene were associated with C6 phosphorylation, whereas polymorphisms in the SBEI and SBEII genes were associated with both C6 and C3 phosphorylation and the SNP in the SSIII gene was associated with C3 phosphorylation. These allelic variants have potential as genetic markers for starch phosphorylation in potato. PMID:25806042

Evaluation of a modified method to measure total starch in animal feeds

USDA-ARS?s Scientific Manuscript database

The AOAC method 996.11 has been recognized as an accurate, repeatable, and efficient method to measure total starch in animal feeds. However, analyzing starch using the AOAC method can be expensive and associated with technical challenges. The objective of this study was to determine if an alternati...

Structure, morphology and functionality of acetylated and oxidised barley starches.

PubMed

El Halal, Shanise Lisie Mello; Colussi, Rosana; Pinto, Vânia Zanella; Bartz, Josiane; Radunz, Marjana; Carreño, Neftali Lenin Villarreal; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2015-02-01

Acetylation and oxidation are chemical modifications which alter the properties of starch. The degree of modification of acetylated and oxidized starches is dependent on the catalyst and active chlorine concentrations, respectively. The objective of this study was to evaluate the effect of acetylation and oxidation on the structural, morphological, physical-chemical, thermal and pasting properties of barley starch. Barley starches were acetylated at different catalyst levels (11%, 17%, and 23% of NaOH solution) and oxidized at different sodium hypochlorite concentrations (1.0%, 1.5%, and 2.0% of active chlorine). Fourier-transformed infrared spectroscopy (FTIR), X-ray diffractograms, thermal, morphological, and pasting properties, swelling power and solubility of starches were evaluated. The degree of substitution (DS) of the acetylated starches increased with the rise in catalyst concentration. The percentage of carbonyl (CO) and carboxyl (COOH) groups in oxidized starches also increased with the rise of active chlorine level. The presence of hydrophobic acetyl groups, carbonyl and carboxyl groups caused a partial disorganization and depolymerization of starch granules. The structural, morphological and functional changes in acetylated and oxidized starches varied according to reaction conditions. Acetylation makes barley starch more hydrophobic by the insertion of acetyl groups. Also the oxidation promotes low retrogradation and viscosity. All these characteristics are important for biodegradable film production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enzyme-Catalyzed Regioselective Modification of Starch Nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chakraborty, Soma; Sahoo, Bishwabhusan; Teraoka, Iwao

The selective esterification of starch nanoparticles was performed using as catalyst Candida antartica Lipase B (CAL-B) in its immobilized (Novozym 435) and free (SP-525) forms. The starch nanoparticles were made accessible for acylation reactions by formation of Aerosol-OT (AOT, bis(2-ethylhexyl)sodium sulfosuccinate) stabilized microemulsions. Starch nanoparticles in microemulsions were reacted with vinyl stearate, ε-caprolactone, and maleic anhydride at 40 °C for 48 h to give starch esters with degrees of substitution (DS) of 0.8, 0.6, and 0.4, respectively. Substitution occurred regioselectively at the C-6 position of the glucose repeat units. Infrared microspectroscopy (IRMS) revealed that AOT-coated starch nanoparticles diffuse into themore » outer 50 μm shell of catalyst beads. Thus, even though CAL-B is immobilized within a macroporous resin, CAL-B is sufficiently accessible to the starch nanoparticles. When free CAL-B was incorporated along with starch within AOT-coated reversed micelles, CAL-B was also active and catalyzed the acylation with vinyl stearate (24 h, 40 °C) to give DS = 0.5. After removal of surfactant from the modified starch nanoparticles, they were dispersed in DMSO or water and were shown to retain their nanodimensions.« less

Comparison of fractionation methods for nitrogen and starch in maize and grass silages.

PubMed

Ali, M; de Jonge, L H; Cone, J W; van Duinkerken, G; Blok, M C; Bruinenberg, M H; Hendriks, W H

2016-06-01

In in situ nylon bag technique, many feed evaluation systems use a washing machine method (WMM) to determine the washout (W) fraction and to wash the rumen incubated nylon bags. As this method has some disadvantages, an alternate modified method (MM) was recently introduced. The aim of this study was to determine and compare the W and non-washout (D+U) fractions of nitrogen (N) and/or starch of maize and grass silages, using the WMM and the MM. Ninety-nine maize silage and 99 grass silage samples were selected with a broad range in chemical composition. The results showed a large range in the W, soluble (S) and D+U fractions of N of maize and grass silages and the W, insoluble washout (W-S) and D+U fractions of starch of maize silages, determined by both methods, due to variation in their chemical composition. The values for N fractions of maize and grass silages obtained with both methods were found different (p < 0.001). Large differences (p < 0.001) were found in the D+U fraction of starch of maize silages which might be due to different methodological approaches, such as different rinsing procedures (washing vs. shaking), duration of rinsing (40 min vs. 60 min) and different solvents (water vs. buffer solution). The large differences (p < 0.001) in the W-S and D+U fractions of starch determined with both methods can led to different predicted values for the effective rumen starch degradability. In conclusion, the MM with one recommended shaking procedure, performed under identical and controlled experimental conditions, can give more reliable results compared to the WMM, using different washing programs and procedures. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

The Other Double Helix--The Fascinating Chemistry of Starch

NASA Astrophysics Data System (ADS)

Hancock, Robert D.; Tarbet, Bryon J.

2000-08-01

Current textbooks deal only briefly with the chemistry of starch. A short review with 21 references is presented, describing the structure of starch and indicating the double helix structure of A-type and B-type starch. The structure of the starch granule is examined, pointing out the existence of growth rings of alternating crystalline and noncrystalline starch, with growing amylopectin molecules extending from the hilum (point of origin) to the surface of the starch granule. The swelling of starch granules in water, above the gelatinization temperature of about 60 °C, is discussed. The process of gelatinization involves unraveling of the starch helix and a manyfold increase in volume of the starch granule as water is imbibed and bound to the unraveled starch polymer by hydrogen bonding. Baking bread or pastries causes unraveling of the starch helix, and the process by which these products become stale corresponds primarily to the re-forming of the starch helix. The importance of this phenomenon in food science is discussed. The absorption of nonpolar linear molecules such as I2, or linear nonpolar portions of molecules such as n-butanol or fats and phospholipids, by the C-type helix of starch is examined. The way in which starch is structurally modified to retard staling is discussed in relation to food technology.

Engineering yeasts for raw starch conversion.

PubMed

van Zyl, W H; Bloom, M; Viktor, M J

2012-09-01

Next to cellulose, starch is the most abundant hexose polymer in plants, an import food and feed source and a preferred substrate for the production of many industrial products. Efficient starch hydrolysis requires the activities of both α-1,4 and α-1,6-debranching hydrolases, such as endo-amylases, exo-amylases, debranching enzymes, and transferases. Although amylases are widely distributed in nature, only about 10 % of amylolytic enzymes are able to hydrolyse raw or unmodified starch, with a combination of α-amylases and glucoamylases as minimum requirement for the complete hydrolysis of raw starch. The cost-effective conversion of raw starch for the production of biofuels and other important by-products requires the expression of starch-hydrolysing enzymes in a fermenting yeast strain to achieve liquefaction, hydrolysis, and fermentation (Consolidated Bioprocessing, CBP) by a single organism. The status of engineering amylolytic activities into Saccharomyces cerevisiae as fermentative host is highlighted and progress as well as challenges towards a true CBP organism for raw starch is discussed. Conversion of raw starch by yeast secreting or displaying α-amylases and glucoamylases on their surface has been demonstrated, although not at high starch loading or conversion rates that will be economically viable on industrial scale. Once efficient conversion of raw starch can be demonstrated at commercial level, engineering of yeast to utilize alternative substrates and produce alternative chemicals as part of a sustainable biorefinery can be pursued to ensure the rightful place of starch converting yeasts in the envisaged bio-economy of the future.

Impact of dry heating on physicochemical properties of corn starch and lysine mixture.

PubMed

Ji, Ying; Yu, Jicheng; Xu, Yongbin; Zhang, Yinghui

2016-10-01

Corn starch was modified with lysine by dry heat treatment and to investigate how they can affect the pasting and structural properties of the treated starches. Dry heating with lysine reduced the pasting temperature and resulting in viscosity increase. The particle size of heated starch-lysine mixture increased, suggesting that starch granules were cross-linked to lysine. After dry heating, the onset temperature, peak temperature and conclusion temperature of corn starch-lysine mixture were lower than those of other starches. The degree of crystallinity decreased for the starch after dry heat treatment while these heated starch samples still have the same X-ray diffraction types as the original starch. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of A Flexible System for the Simultaneous Conversion of Biomass to Industrial Chemicals and the Production of Industrial Biocatalysts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Johnway; Hooker, Brian S.; Skeen, R S.

2002-01-01

A flexible system was developed for the simultaneous conversion of biomass to industrial chemicals and the production of industrial biocatalysts. In particular, the expression of a bacterial enzyme, beta-glucuronidase (GUS), was investigated using a genetically modified starch-degrading Saccharomyces strain in suspension cultures in starch media. Different sources of starch including corn and waste potato starch were used for yeast biomass accumulation and GUS expression studies under controls of inducible and constitutive promoters. A thermostable bacterial cellulase, Acidothermus cellulolyticus E1 endoglucanase gene was also cloned into an episomal plasmid expression vector and expressed in the starch-degrading Saccharomyces strain.

Reduction of acrylamide content in bread crust by starch coating.

PubMed

Liu, Jie; Liu, Xiaojie; Man, Yong; Liu, Yawei

2018-01-01

A technique of starch coating to reduce acrylamide content in bread crust was proposed. Bread was prepared in accordance with a conventional procedure and corn or potato starch coating was brushed on the surface of the fermented dough prior to baking. Corn starch coating caused a decrease in acrylamide of 66.7% and 77.1% for the outer and inner crust, respectively. The decrease caused by the potato starch coating was 68.4% and 77.4%, respectively. Starch coating reduced asparagine content significantly (43.4-82.9%; P < 0.01)in both the outer and inner crust. A lower temperature (difference of 10-20 °C) in combination with a higher moisture content (maximum difference of 8%) of bread crust were a result of starch coating, which effectively shortened the time span (4-8 min) over which acrylamide could form and accumulate. The present study demonstrates that starch coating could be a simple, effective and practical application for reducing acrylamide levels in bread crust without changing the texture and crust color of bread. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Ion exchanger from chemically modified banana leaves.

PubMed

El-Gendy, Ahmed A; Mohamed, Samar H; Abd-Elkader, Amal H

2013-07-25

Cation exchangers from chemically modified banana leaves have been prepared. Banana leaves were treated with different molarities of KMnO4 and cross linked with epichlorohydrin and their effect on metal ion adsorption was investigated. Phosphorylation of chemically modified banana leaves was also studied. The metal ion uptake by these modified banana leaves was clarified. Effect of different varieties, e.g. activation of produced cation exchanger, concentration of metal ions was also investigated. Characterization of the prepared ion exchangers by using infrared and thermal analysis was also taken in consideration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Preparation and structural characterization of corn starch-aroma compound inclusion complexes.

PubMed

Zhang, Shu; Zhou, Yibin; Jin, Shanshan; Meng, Xin; Yang, Liping; Wang, Haisong

2017-01-01

Six corn starch inclusion complexes were synthesized using small nonpolar or weak polar aroma compounds (heptanolide, carvone and menthone) and small polar aroma compounds (linalool, heptanol and menthol). The objectives of this study were to (a) investigate the ability of corn starch to form inclusion complexes with these aroma compounds and (b) characterize the structure of the corn starch inclusion complexes. The resulting inclusion ratios were 75.6, 36.9, 43.8, 91.9, 67.2 and 54.7% for heptanolide, carvone, menthone, linalool, heptanol and menthol respectively. The inclusion complexes had laminated structures with a certain amount of holes or blocky constructions. Compared with gelatinized corn starch, the transition temperatures, peak temperatures and enthalpies of the inclusion complexes were significantly different. The major peak of CO at 1771 cm -1 and significant peak shifts revealed the formation of inclusion complexes. X-ray diffractometry (XRD) analyses revealed that the crystallinity of corn starch-polar aroma compound inclusion complexes increased. Based on cross-polarization magic angle spinning 13 C nuclear magnetic resonance (CP-MAS 13 C NMR) results, novel peaks and chemical shifts were attributed to the presence of small aroma compounds, thereby confirming the formation of corn starch inclusion complexes. Small nonpolar and polar aroma compounds can be complexed to corn starch. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Room temperature preparation of fluorescent starch nanoparticles from starch-dopamine conjugates and their biological applications.

PubMed

Shi, Yingge; Xu, Dazhuang; Liu, Meiying; Fu, Lihua; Wan, Qing; Mao, Liucheng; Dai, Yanfeng; Wen, Yuanqing; Zhang, Xiaoyong; Wei, Yen

2018-01-01

Fluorescent organic nanoparticles (FONs) have been regarded as the promising candidates for biomedical applications owing to their well adjustment of chemical structure and optical properties and good biological properties. However, the preparation of FONs from the natural derived polymers has been rarely reported thus far. In current work, we reported a novel strategy for preparation of FONs based on the self-polymerization of starch-dopamine conjugates and polyethyleneimine in rather mild experimental conditions, including air atmosphere, aqueous solution, absent catalysts and at room temperature. The morphology, chemical structure and optical properties of the resultant starch-based FONs were investigated by different characterization techniques. Biological evaluation results demonstrated that these starch-based FONs possess good biocompatibility and fluorescent imaging performance. More importantly, the novel strategy might also be extended for the preparation of many other carbohydrate polymers based FONs with different structure and functions. Therefore, this work opens a new avenue for the preparation and biomedical applications of luminescent carbohydrate polymers. Copyright © 2017 Elsevier B.V. All rights reserved.

The in vitro effects of retrograded starch (resistant starch type 3) from lotus seed starch on the proliferation of Bifidobacterium adolescentis.

PubMed

Zhang, Yi; Wang, Ying; Zheng, Baodong; Lu, Xu; Zhuang, Weijing

2013-11-01

Prebiotics such as oligosaccharides, fructans, and resistant starch (RS) stimulate the growth of beneficial bacteria in large bowel and modify the human gastrointestinal environment. In this study, compared with glucose (GLU) and high amylose maize starch (HAMS), the in vitro effects of LRS3 and P-LRS3 (RS3 and purified RS3 prepared from lotus seed starch) on the proliferation of bifidobacteria were assessed by assessing the changes in optical density (OD), pH values, short chain fatty acid (SCFA) production, and tolerance ability to gastrointestinal conditions. Significantly higher OD values were obtained from media containing LRS3 and P-LRS3, and especially in the medium containing P-LRS3, the OD value of which reached 1.36 when the concentration of the carbon source was 20 g L(-1). Additionally, the lag phase of bifidobacteria was 8 h in the medium with LRS3 or P-LRS3, whereas it was 16 h in the medium with GLU or HAMS. What is more, a higher content of butyric acid was obtained in the P-LRS3 medium. Compared with GLU and HAMS media, bifidobacteria had a higher tolerance to gastrointestinal conditions in LRS3 and P-LRS3 media. It shows that lotus seed resistant starch, especially P-LRS3, could stimulate the growth of bifidobacteria. The rough surface of resistant starch and the SCFAs produced during fermentation might influence the proliferation of bifidobacteria.

Structural and molecular basis of starch viscosity in hexaploid wheat.

PubMed

Ral, J-P; Cavanagh, C R; Larroque, O; Regina, A; Morell, M K

2008-06-11

Wheat starch is considered to have a low paste viscosity relative to other starches. Consequently, wheat starch is not preferred for many applications as compared to other high paste viscosity starches. Increasing the viscosity of wheat starch is expected to increase the functionality of a range of wheat flour-based products in which the texture is an important aspect of consumer acceptance (e.g., pasta, and instant and yellow alkaline noodles). To understand the molecular basis of starch viscosity, we have undertaken a comprehensive structural and rheological analysis of starches from a genetically diverse set of wheat genotypes, which revealed significant variation in starch traits including starch granule protein content, starch-associated lipid content and composition, phosphate content, and the structures of the amylose and amylopectin fractions. Statistical analysis highlighted the association between amylopectin chains of 18-25 glucose residues and starch pasting properties. Principal component analysis also identified an association between monoesterified phosphate and starch pasting properties in wheat despite the low starch-phosphate level in wheat as compared to tuber starches. We also found a strong negative correlation between the phosphate ester content and the starch content in flour. Previously observed associations between internal starch granule fatty acids and the swelling peak time and pasting temperature have been confirmed. This study has highlighted a range of parameters associated with increased starch viscosity that could be used in prebreeding/breeding programs to modify wheat starch pasting properties.

Resistant starch intakes in the United States.

PubMed

Murphy, Mary M; Douglass, Judith Spungen; Birkett, Anne

2008-01-01

Dietary fiber represents a broad class of undigested carbohydrate components. The components vary in chemical and physical nature and in their physiological outcomes. Resistant starch is starch that escapes digestion in the small intestine and that may be fermented in the large intestine. The purpose of this study was to estimate consumption of resistant starch by the US population and to identify key sources of dietary resistant starch. A database of resistant starch concentrations in foods was developed from the publicly available literature. These concentrations were linked to foods reported in 24-hour dietary recalls from participants in the 1999-2002 National Health and Nutrition Examination Surveys and estimates of resistant starch intakes were generated. The study population included 18,305 nonbreastfeeding individuals in the United States. The dietary intake of resistant starch was determined for 10 US subpopulations defined by age, sex, and race/ethnicity. Three estimates of resistant starch intake were made for each person based on the minimum, mean, and maximum concentrations of resistant starch in the foods consumed. Americans aged 1 year and older were estimated to consume approximately 4.9 g resistant starch per day based on mean resistant starch concentrations (range 2.8 to 7.9 g resistant starch per day). Breads, cooked cereals/pastas, and vegetables (other than legumes) contributed 21%, 19%, and 19% of total resistant starch intake, respectively, and were top sources of resistant starch. Findings from this study suggest that the estimated intake of resistant starch by Americans is approximately 3 to 8 g per person per day. These estimates of resistant starch intake provide a valuable reference for researchers and food and nutrition professionals and will allow for more accurate estimates of total intakes of carbohydrate compounds that escape digestion in the small intestine.

Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

PubMed

Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

2014-10-01

The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

Flocculation and coalescence of droplets in oil-in-water emulsions formed with highly hydrolysed whey proteins as influenced by starch.

PubMed

Ye, Aiqian; Hemar, Yacine; Singh, Harjinder

2004-10-10

The effects of added unmodified amylopectin starch, modified amylopectin starch and amylose starch on the formation and properties of emulsions (4 wt.% corn oil) made with an extensively hydrolysed commercial whey protein (WPH) product under a range of conditions were examined. The rate of coalescence was calculated based on the changes in the droplet size of the emulsions during storage at 20 degrees C. The rates of creaming and coalescence in emulsions containing amylopectin starches were enhanced with increasing concentration of the starches during storage for up to 7 days. At a given starch concentration, the rate of coalescence was higher in the emulsions containing modified amylopectin starch than in those containing unmodified amylopectin starch, whereas it was lowest in the emulsions containing amylose starch. All emulsions containing unmodified and modified amylopectin starches showed flocculation of oil droplets by a depletion mechanism. However, flocculation was not observed in the emulsions containing amylose starch. The extent of flocculation was considered to correlate with the rate of coalescence of oil droplets. The different rates of coalescence could be explained on the basis of the strength of the depletion potential, which was dependent on the molecular weight and the radius of gyration of the starches. At high levels of starch addition (>1.5%), the rate of coalescence decreased gradually, apparently because of the high viscosity of the aqueous phase caused by the starch.

Composition, structure, physicochemical properties, and modifications of cassava starch.

PubMed

Zhu, Fan

2015-05-20

Cassava is highly tolerant to harsh climatic conditions and has great productivity on marginal lands. The supply of cassava starch, the major component of the root, is thus sustainable and cheap. This review summarizes the current knowledge of the composition, physical and chemical structures, physicochemical properties, nutritional quality, and modifications of cassava starch. Research opportunities to better understand this starch are provided. Copyright © 2014 Elsevier Ltd. All rights reserved.

Continuous-flow electro-assisted acid hydrolysis of granular potato starch via inductive methodology.

PubMed

Li, Dandan; Yang, Na; Jin, Yamei; Guo, Lunan; Zhou, Yuyi; Xie, Zhengjun; Jin, Zhengyu; Xu, Xueming

2017-08-15

The induced electric field assisted hydrochloric acid (IEF-HCl) hydrolysis of potato starch was investigated in a fluidic system. The impact of various reaction parameters on the hydrolysis rate, including reactor number (1-4), salt type (KCl, MgCl 2 , FeCl 3 ), salt concentration (3-12%), temperature (40-55°C), and hydrolysis time (0-60h), were comprehensively assessed. Under optimal conditions, the maximum reducing sugar content in the hydrolysates was 10.59g/L. X-ray diffraction suggested that the crystallinity of IEF-HCl-modified starches increased with the intensification of hydrolysis but was lower than that of native starch. Scanning electron microscopy indicated that the surface and interior regions of starch granules were disrupted by the hydrolysis. The solubility of IEF-HCl-modified starches increased compared to native starch while their swelling power decreased, contributing to a decline in paste viscosity. These results suggest that IEF is a notable potential electrotechnology to conventional hydrolysis under mild conditions without any electrode touching the subject. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of Preexercise Ingestion of Modified Amylomaize Starch on Glycemic Response While Cycling.

PubMed

Parks, Rachel B; Angus, Hector F; King, Douglas S; Sharp, Rick L

2018-01-01

Amylomaize-7 is classified as a resistant corn starch and is 68% digestible. When modified by partial hydrolysis in ethanol and hydrochloric acid its digestibility is 92%, yet retains its low glycemic and insulinemic properties. The purpose of this study was to characterize the metabolic response when modified amylomaize-7 or dextrose is consumed in the hour before exercise, and to compare the effect on performance of a brief high-intensity cycling trial. Ten male, trained cyclists were given 1 g/kg body mass of dextrose (DEX) or modified amylomaize-7 (AMY-7) or a flavored water placebo (PL) 45 min prior to exercise on a cycle ergometer. A 15-min ride at 60% W max was immediately followed by a self-paced time trial (TT) equivalent to 15 min at 80% W max . When cyclists consumed DEX, mean serum glucose concentration increased by 3.3 ± 2.1 mmol/L before exercise, compared to stable serum glucose observed for AMY-7 or PL. Glucose concentrations returned to baseline by pre-TT in all treatments. However, the mean post-TT glucose concentration of the DEX group was significantly lower than baseline, AMY-7, or PL. Serum insulin concentration increased nine-fold from baseline to preexercise in the DEX trial, whereas PL or AMY-7 remained unchanged. Time required to complete the performance trial was not significantly different between DEX, AMY-7 or PL. Preexercise ingestion of modified amylomaize-7 compared to dextrose resulted in a more stable serum glucose concentration, but did not offer a performance advantage in this high-intensity cycling trial.

Effect of storage on the chemical composition, microbiological load, and sensory properties of cassava starch-based custard powder

PubMed Central

Awoyale, Wasiu; Sanni, Lateef O; Shittu, Taofik A; Adegunwa, Mojisola O

2015-01-01

The effect of storage on the chemical, microbiological, and sensory properties of cassava starch-based custard powder (CbCP) blends as mixture of yellow-fleshed cassava root starch (YfCRS) (90–98%) and whole egg powder (WEP) (2–10%) was investigated. These were prepared using central composite rotatable design, and separately packaged in polyvinyl chloride plastic can and stored in storage box (30 ± 2°C). The chemical and microbiological analyses of the stored CbCP were evaluated at 3 weeks intervals, while the sensory property was determined at 6 weeks interval for 24 weeks. The result showed that the protein, fat, and the total-β-carotene contents of the CbCP decreased significantly (P ≤ 0.001) after storage while moisture content and microbiological load increased. All the CbCP sensory attributes were accepted at the end of storage, except taste and color. The CbCP gruel prepared from 94% YfCRS: 0.34% WEP and 90% YfCRS: 2% WEP blends were the most acceptable after storage. PMID:26405528

Effect of storage on the chemical composition, microbiological load, and sensory properties of cassava starch-based custard powder.

PubMed

Awoyale, Wasiu; Sanni, Lateef O; Shittu, Taofik A; Adegunwa, Mojisola O

2015-09-01

The effect of storage on the chemical, microbiological, and sensory properties of cassava starch-based custard powder (CbCP) blends as mixture of yellow-fleshed cassava root starch (YfCRS) (90-98%) and whole egg powder (WEP) (2-10%) was investigated. These were prepared using central composite rotatable design, and separately packaged in polyvinyl chloride plastic can and stored in storage box (30 ± 2°C). The chemical and microbiological analyses of the stored CbCP were evaluated at 3 weeks intervals, while the sensory property was determined at 6 weeks interval for 24 weeks. The result showed that the protein, fat, and the total-β-carotene contents of the CbCP decreased significantly (P ≤ 0.001) after storage while moisture content and microbiological load increased. All the CbCP sensory attributes were accepted at the end of storage, except taste and color. The CbCP gruel prepared from 94% YfCRS: 0.34% WEP and 90% YfCRS: 2% WEP blends were the most acceptable after storage.

Dielectric spectroscopy of Ag-starch nanocomposite films

NASA Astrophysics Data System (ADS)

Meena; Sharma, Annu

2018-04-01

In the present work Ag-starch nanocomposite films were fabricated via chemical reduction route. The formation of Ag nanoparticles was confirmed using transmission electron microscopy (TEM). Further the effect of varying concentration of Ag nanoparticles on the dielectric properties of starch has been studied. The frequency response of dielectric constant (ε‧), dielectric loss (ε″) and dissipation factor tan(δ) has been studied in the frequency range of 100 Hz to 1 MHz. Dielectric data was further analysed using Cole-Cole plots. The dielectric constant of starch was found to be 4.4 which decreased to 2.35 in Ag-starch nanocomposite film containing 0.50 wt% of Ag nanoparticles. Such nanocomposites with low dielectric constant have potential applications in microelectronic technologies.

Effects of tempering (annealing), acid hydrolysis, low-citric acid substitution on chemical and physicochemical properties of starches of four yam (Dioscorea spp.) cultivars.

PubMed

Falade, Kolawole O; Ayetigbo, Oluwatoyin E

2017-05-01

The effects of tempering (annealing), acid hydrolysis and low-citric acid substitution on chemical and physicochemical properties of starches of four Nigerian yam cultivars were investigated. Crude fat and protein contents of the native starches decreased significantly after the modifications, while nitrogen-free extract increased significantly with acid hydrolysis and citric acid substitution. Acid hydrolysis and low-citric acid substitution reduced the least concentration for gel formation of the starches from 4 to 2% w/v, but tempering had no effect. Swelling power of the starches reduced significantly, and water solubility increased significantly at 75 and 85 °C, especially with acid hydrolysis and low-citric acid substitution. However, tempering significantly reduced starch solubility in the four cultivars. Paste clarity of starches of white (29.17%), water (18.90%), yellow (30.90%) and bitter (10.57%) yams reduced significantly with tempering to 14.43, 11.83, 16.93 and 7.27%, but increased significantly with acid hydrolysis to 41.40, 35.37, 28.77 and 32.33%, and low-citric acid substitution to 36.60, 44.17, 50.67 and 14.33%, respectively. Pasting properties such as peak, trough, breakdown, final, and setback viscosities and peak time of native starches reduced significantly with acid hydrolysis and low-citric acid substitution, however, tempering significantly increased their pasting temperature, peak time, setback and final viscosities.

An evaluation of total starch and starch gelatinization methodologies in pelleted animal feed.

PubMed

Zhu, L; Jones, C; Guo, Q; Lewis, L; Stark, C R; Alavi, S

2016-04-01

The quantification of total starch content (TS) or degree of starch gelatinization (DG) in animal feed is always challenging because of the potential interference from other ingredients. In this study, the differences in TS or DG measurement in pelleted swine feed due to variations in analytical methodology were quantified. Pelleted swine feed was used to create 6 different diets manufactured with various processing conditions in a 2 × 3 factorial design (2 conditioning temperatures, 77 or 88°C, and 3 conditioning retention times, 15, 30, or 60 s). Samples at each processing stage (cold mash, hot mash, hot pelletized feed, and final cooled pelletized feed) were collected for each of the 6 treatments and analyzed for TS and DG. Two different methodologies were evaluated for TS determination (the AOAC International method 996.11 vs. the modified glucoamylase method) and DG determination (the modified glucoamylase method vs. differential scanning calorimetry [DSC]). For TS determination, the AOAC International method 996.11 measured lower TS values in cold pellets compared with the modified glucoamylase method. The AOAC International method resulted in lower TS in cold mash than cooled pelletized feed, whereas the modified glucoamylase method showed no significant differences in TS content before or after pelleting. For DG, the modified glucoamylase method demonstrated increased DG with each processing step. Furthermore, increasing the conditioning temperature and time resulted in a greater DG when evaluated by the modified glucoamylase method. However, results demonstrated that DSC is not suitable as a quantitative tool for determining DG in multicomponent animal feeds due to interferences from nonstarch transformations, such as protein denaturation.

Octenylsuccinate starch spherulites as a stabilizer for Pickering emulsions.

PubMed

Wang, Chan; Fu, Xiong; Tang, Chuan-He; Huang, Qiang; Zhang, Bin

2017-07-15

This study investigated structure and morphology of starch spherulites prepared from debranched waxy maize and waxy potato starches. Debranched waxy potato starch favored the formation of B-type crystals with longer branch chains (average chain length, 26.14), whereas A-type polymorphic aggregates were generated from debranched waxy maize under same recrystallization condition. Spherulites had smaller particle size distribution (D[3,2], ∼3.7μm), higher dissociation temperature (80-120°C) and crystallinity (80∼90%), compared to native waxy starches. Intact spherulites could be used as an edible particle emulsifier after modifying by octenylsuccinic anhydride (OSA). The emulsion produced using 2wt.% of octenylsuccinate (OS) starch spherulites as emulsifier was quite stable over 2months, and its Pickering emulsions displayed protective effect on stability of oil droplets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quality characteristics of low fat ostrich meat patties formulated with either pork lard or modified corn starch, soya isolate and water.

PubMed

Hoffman, L C; Mellett, F D

2003-10-01

A trained taste panel could not distinguish (P>0.05) between ostrich meat patties containing either 10% pork lard or 10% of a modified starch/protein isolate (fat replacer) mixture. The panel could distinguish between the types of ostrich muscle/meat cuts used with a significant (P<0.05) number preferring ostrich patties made from meat containing a higher collagen content (±3% vs <1%). The chemical analysis of the patties showed that within the meat classes (Class fillet-de-membraned, Class A-very lean off-cuts and Class B-off-cuts containing visual connective tissue and some fat), the patties containing the pork fat had a +6% higher total fat content than those containing the fat replacer. The fatty acid profiles of the various products were in accordance with the meat type and fat or fat replacer used. The mineral profile was as expected for lean ostrich meat that had spices added. It is concluded that fat replacers can be used successfully for the production of low fat ostrich patties without any negative quality attributes being perceived.

Total chemical synthesis of modified histones

NASA Astrophysics Data System (ADS)

Qi, Yun-Kun; Ai, Hua-Song; Li, Yi-Ming; Yan, Baihui

2018-02-01

In the post-genome era, epigenetics has received increasing attentions in recent years. The post-translational modifications (PTMs) of four core histones play central roles in epigenetic regulation of eukaryotic genome by either directly altering the biophysical properties of nucleosomes or by recruiting other effector proteins. In order to study the biological functions and structural mechanisms of these histone PTMs, an obligatory step is to prepare a sufficient amount of homogeneously modified histones. This task cannot be fully accomplished either by recombinant technology or enzymatic modification. In this context, synthetic chemists have developed novel protein synthetic tools and state-of-the-art chemical ligation strategies for the preparation of homologous modified histones. In this review, we summarize the recent advances in the preparation of modified histones, focusing on the total chemical synthesis strategies. The importance and potential of synthetic chemistry for the study of histone code will be also discussed.

Effect of genotype and environment on the concentrations of starch and protein in, and the physicochemical properties of starch from, field pea and fababean.

PubMed

Hood-Niefer, Shannon D; Warkentin, Thomas D; Chibbar, Ravindra N; Vandenberg, Albert; Tyler, Robert T

2012-01-15

The effects of genotype and environment and their interaction on the concentrations of starch and protein in, and the amylose content and thermal and pasting properties of starch from, pea and fababean are not well known. Differences due to genotype were observed in the concentrations of starch and protein in pea and fababean, in the onset temperature (To) and peak temperature (Tp) of gelatinization of fababean starch, and in the pasting, trough, cooling and final viscosities of pea starch and fababean starch. Significant two-way interactions (location × genotype) were observed for the concentration of starch in fababean and the amylose content, To, endothermic enthalpy of gelatinization (ΔH) and trough viscosity of fababean starch. Significant three-way interactions (location × year × genotype) were observed for the concentration of starch in pea and the pasting, trough, cooling and final viscosities of pea starch. Differences observed in the concentrations of starch and protein in pea and fababean were sufficient to be of practical significance to end-users, but the relatively small differences in amylose content and physicochemical properties of starch from pea and fababean were not. Copyright © 2011 Society of Chemical Industry.

Effect of citric acid concentration and hydrolysis time on physicochemical properties of sweet potato starches.

PubMed

Surendra Babu, Ayenampudi; Parimalavalli, Ramanathan; Rudra, Shalini Gaur

2015-09-01

Physicochemical properties of citric acid treated sweet potato starches were investigated in the present study. Sweet potato starch was hydrolyzed using citric acid with different concentrations (1 and 5%) and time periods (1 and 11 h) at 45 °C and was denoted as citric acid treated starch (CTS1 to CTS4) based on their experimental conditions. The recovery yield of acid treated starches was above 85%. The CTS4 sample displayed the highest amylose (around 31%) and water holding capacity its melting temperature was 47.66 °C. The digestibility rate was slightly increased for 78.58% for the CTS3 and CTS4. The gel strength of acid modified starches ranged from 0.27 kg to 1.11 kg. RVA results of acid thinned starches confirmed a low viscosity profile. CTS3 starch illustrated lower enthalpy compared to all other modified starches. All starch samples exhibited a shear-thinning behavior. SEM analysis revealed that the extent of visible degradation was increased at higher hydrolysis time and acid concentration. The CTS3 satisfied the criteria required for starch to act as a fat mimetic. Overall results conveyed that the citric acid treatment of sweet potato starch with 5% acid concentration and 11h period was an ideal condition for the preparation of a fat replacer. Copyright © 2015 Elsevier B.V. All rights reserved.

Surface modification of starch based blends using potassium permanganate-nitric acid system and its effect on the adhesion and proliferation of osteoblast-like cells.

PubMed

Pashkuleva, I; Marques, A P; Vaz, F; Reis, R L

2005-01-01

The surface modification of three starch based polymeric biomaterials, using a KMnO4/HNO3 oxidizing system, and the effect of that modification on the osteoblastic cell adhesion has been investigated. The rationale of this work is as follows--starch based polymers have been proposed for use as tissue engineering scaffolds in several publications. It is known that in biodegradable systems it is quite difficult to have both cell adhesion and proliferation. Starch based polymers have shown to perform better than poly-lactic acid based materials but there is still room for improvement. This particular work is aimed at enhancing cell adhesion and proliferation on the surface of several starch based polymer blends that are being proposed as tissue engineering scaffolds. The surface of the polymeric biomaterials was chemically modified using a KMnO4/HNO3 system. This treatment resulted in more hydrophilic surfaces, which was confirmed by contact angle measurements. The effect of the treatment on the bioactivity of the surface modified biomaterials was also studied. The bioactivity tests, performed in simulated body fluid after biomimetic coating, showed that a dense film of calcium phosphate was formed after 30 days. Finally, human osteoblast-like cells were cultured on unmodified (control) and modified materials in order to observe the effect of the presence of higher numbers of polar groups on the adhesion and proliferation of those cells. Two of the modified polymers presented changes in the adhesion behavior and a significant increase in the proliferation rate kinetics when compared to the unmodified controls.

Characterization and Prebiotic Effect of the Resistant Starch from Purple Sweet Potato.

PubMed

Zheng, Yafeng; Wang, Qi; Li, Baoyu; Lin, Liangmei; Tundis, Rosa; Loizzo, Monica R; Zheng, Baodong; Xiao, Jianbo

2016-07-19

Purple sweet potato starch is a potential resource for resistant starch production. The effects of heat-moisture treatment (HMT) and enzyme debranching combined heat-moisture treatment (EHMT) on the morphological, crystallinity and thermal properties of PSP starches were investigated. The results indicated that, after HMT or EHMT treatments, native starch granules with smooth surface was destroyed to form a more compact, irregular and sheet-like structure. The crystalline pattern was transformed from C-type to B-type with decreasing relative crystallinity. Due to stronger crystallites formed in modified starches, the swelling power and solubility of HMT and EHMT starch were decreased, while the transition temperatures and gelatinization enthalpy were significantly increased. In addition, HMT and EHMT exhibited greater effects on the proliferation of bifidobacteria compared with either glucose or high amylose maize starch.

Preparation and characterization of acorn starch/poly(lactic acid) composites modified with functionalized vegetable oil derivates.

PubMed

Li, Shouhai; Xia, Jianling; Xu, Yuzhi; Yang, Xuejuan; Mao, Wei; Huang, Kun

2016-05-20

Composites of acorn starch (AS) and poly(1actic acid) (PLA) modified with dimer fatty acid (DFA) or dimer fatty acid polyamide (DFAPA) were produced by a hot-melt extrusion method. The effects of DFA and DFAPA contents on the mechanical, hydrophobic, thermal properties and melt fluidity of the composites were studied under an invariable AS-to-PLA mass ratio of 40/60. SEM and DMA research results show that the compatibility of AS/PLA composites are determined by the dosage of DFA or DFAPA. The hydrophobicity and melt fluidity of composites are improved with the addition of DFA and DFAPA. The glass transition temperatures of the composites are all reduced remarkably by additives DFA and DFAPA. However, DFA and DFAPA exert different effects on the mechanical properties of AS/PLA composites. In the DFAPA-modified system, the tensile and flexural strength first increase and then decrease with the increase of DFAPA dosage; the mechanical strength is maximized when the dosage of DFAPA is 2 wt% of total weight. In the DFA-modified system, the tensile and flexural strength decrease with the increase of DFA dosage. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimating Starch Content in Roots of Deciduous Trees--A Visual Technique

Treesearch

Philip M. Wargo; Philip M. Wargo

1975-01-01

A visual technique for determining starch content in roots of forest trees, based onz iodine-staining of starch granules, was compared with a chemical method. Although the chemical method was more precise, roots could be sorted with the visual method into groups that are probably biologically important. The visual technique is simple and can be adapted for use in the...

Starch Biorefinery Enzymes.

PubMed

Läufer, Albrecht

2017-03-07

Nature uses enzymes to build and convert biomass; mankind uses the same enzymes and produces them on a large scale to make optimum use of biomass in biorefineries. Bacterial α-amylases and fungal glucoamylases have been the workhorses of starch biorefineries for many decades. Pullulanases were introduced in the 1980s. Proteases, cellulases, hemicellulases, and phytases have been on the market for a few years as process aids, improving yields, performance, and costs. Detailed studies of the complex chemical structures of biomass and of the physicochemical limitations of industrial biorefineries have led enzyme developers to produce novel tailor-made solutions for improving yield and profitability in the industry. This chapter reviews the development of enzyme applications in the major starch biorefining processes.

Rheology of different hydrocolloids–rice starch blends. Effect of successive heating–cooling cycles

USDA-ARS?s Scientific Manuscript database

Hydrocolloids are frequently used for modifying starch functionality. In the present study the possible interaction of three different hydrocolloids - guar gum, hydroxypropylmethylcellulose (HPMC) and xanthan gum - with rice starch was explored by determining the pasting, viscoelastic and swelling ...

Sorghum starch properties as affected by growing season, hybrid, and kernel maturity

USDA-ARS?s Scientific Manuscript database

Starch is a widely used component in the food, feed, and biofuel industries. Critical components in the functionality of a starch in a food or industrial system are the thermal properties. The objective of this study was to evaluate the physical and chemical changes that occur in sorghum starch du...

Correlation of concentration of modified cassava flour for banana fritter flour using simple linear regression

NASA Astrophysics Data System (ADS)

Herminiati, A.; Rahman, T.; Turmala, E.; Fitriany, C. G.

2017-12-01

The purpose of this study was to determine the correlation of different concentrations of modified cassava flour that was processed for banana fritter flour. The research method consists of two stages: (1) to determine the different types of flour: cassava flour, modified cassava flour-A (using the method of the lactid acid bacteria), and modified cassava flour-B (using the method of the autoclaving cooling cycle), then conducted on organoleptic test and physicochemical analysis; (2) to determine the correlation of concentration of modified cassava flour for banana fritter flour, by design was used simple linear regression. The factors were used different concentrations of modified cassava flour-B (y1) 40%, (y2) 50%, and (y3) 60%. The response in the study includes physical analysis (whiteness of flour, water holding capacity-WHC, oil holding capacity-OHC), chemical analysis (moisture content, ash content, crude fiber content, starch content), and organoleptic (color, aroma, taste, texture). The results showed that the type of flour selected from the organoleptic test was modified cassava flour-B. Analysis results of modified cassava flour-B component containing whiteness of flour 60.42%; WHC 41.17%; OHC 21.15%; moisture content 4.4%; ash content 1.75%; crude fiber content 1.86%; starch content 67.31%. The different concentrations of modified cassava flour-B with the results of the analysis provides correlation to the whiteness of flour, WHC, OHC, moisture content, ash content, crude fiber content, and starch content. The different concentrations of modified cassava flour-B does not affect the color, aroma, taste, and texture.

Resistant Starch Regulates Gut Microbiota: Structure, Biochemistry and Cell Signalling.

PubMed

Yang, Xiaoping; Darko, Kwame Oteng; Huang, Yanjun; He, Caimei; Yang, Huansheng; He, Shanping; Li, Jianzhong; Li, Jian; Hocher, Berthold; Yin, Yulong

2017-01-01

Starch is one of the most popular nutritional sources for both human and animals. Due to the variation of its nutritional traits and biochemical specificities, starch has been classified into rapidly digestible, slowly digestible and resistant starch. Resistant starch has its own unique chemical structure, and various forms of resistant starch are commercially available. It has been found being a multiple-functional regulator for treating metabolic dysfunction. Different functions of resistant starch such as modulation of the gut microbiota, gut peptides, circulating growth factors, circulating inflammatory mediators have been characterized by animal studies and clinical trials. In this mini-review, recent remarkable progress in resistant starch on gut microbiota, particularly the effect of structure, biochemistry and cell signaling on nutrition has been summarized, with highlights on its regulatory effect on gut microbiota. © 2017 The Author(s). Published by S. Karger AG, Basel.

Encapsulation of Organic Chemicals within a Starch Matrix.

ERIC Educational Resources Information Center

Wing, R. E.; Shasha, B. S.

1983-01-01

Three experiments demonstrating the feasibility of encapsulating liquids within a starch matrix are described, including encapsulation of linseed oil using the zanthate method and of turpentine and butylate using the calcium adduct procedure. Encapsulated materials, including pesticides, are slowly released from the resulting matrix. Considers…

Horse chestnut (Aesculus hippocastanum L.) starch: Basic physico-chemical characteristics and use as thermoplastic material.

PubMed

Castaño, J; Rodríguez-Llamazares, S; Contreras, K; Carrasco, C; Pozo, C; Bouza, R; Franco, C M L; Giraldo, D

2014-11-04

Starch isolated from non-edible Aesculus hippocastanum seeds was characterized and used for preparing starch-based materials. The apparent amylose content of the isolated starch was 33.1%. The size of starch granules ranged from 0.7 to 35 μm, and correlated with the shape of granules (spherical, oval and irregular). The chain length distribution profile of amylopectin showed two peaks, at polymerization degree (DP) of 12 and 41-43. Around 53% of branch unit chains had DP in the range of 11-20. A. hippocastanum starch displayed a typical C-type pattern and the maximum decomposition temperature was 317 °C. Thermoplastic starch (TPS) prepared from A. hippocastanum with glycerol and processed by melt blending exhibited adequate mechanical and thermal properties. In contrast, plasticized TPS with glycerol:malic acid (1:1) showed lower thermal stability and a pasty and sticky behavior, indicating that malic acid accelerates degradation of starch during processing. Copyright © 2014 Elsevier Ltd. All rights reserved.

In vitro digestibility of normal and waxy corn starch is modified by the addition of Tween 80.

PubMed

Vernon-Carter, E J; Alvarez-Ramirez, J; Bello-Perez, L A; Garcia-Hernandez, A; Roldan-Cruz, C; Garcia-Diaz, S

2018-05-15

Aqueous dispersions of normal and waxy corn starch (3% w/w) were mixed with Tween 80 (0, 7.5, 15, 22.5 and 30 g/100 g of starch), and gelatinized (90 °C, 20 min). Optical microscopy of the gelatinized starch dispersions (GSD x ; x = Tween 80 concentration) revealed that the microstructure was characterized by a continuous phase of leached amylose and amylopectin entangled chains, and a dispersed phase of insoluble remnants, called ghosts, on whose surface small granules were observed, imputed to Tween 80. The apparent viscosity of the GSD x decreased as the concentration of Tween 80 increased (up to about 70-90%). FTIR analysis of dried GSD x indicated that Tween 80 addition decreased short-range ordering. The content of rapidly digestible starch (RDS) and resistant starch (RS) fractions tended to increase significantly, at the expense of a significant decrease of slowly digestible starch (SDS) fraction, an effect that may be attributed to the increase of amorphous structures and starch chain-surfactant complexes. The RDS and RS increase was more pronounced for normal than for waxy corn starch, and the significance of the increase was dependent on Tween 80 concentration. Overall, the results showed that surfactant can affect largely the digestibility of starch chains. Copyright © 2018 Elsevier B.V. All rights reserved.

Structural modification in the formation of starch - silver nanocomposites

NASA Astrophysics Data System (ADS)

Begum, S. N. Suraiya; Aswal, V. K.; Ramasamy, Radha Perumal

2016-05-01

Polymer based nanocomposites have gained wide applications in field of battery technology. Starch is a naturally occurring polysaccharide with sustainable properties such as biodegradable, non toxic, excellent film forming capacity and it also act as reducing agent for the metal nanoparticles. In our research various concentration of silver nitrate (AgNO3) was added to the starch solution and films were obtained using solution casting method. Surface electron microscope (SEM) of the films shows modifications depending upon the concentration of AgNO3. Small angle neutron scattering (SANS) analysis showed that addition of silver nitrate modifies the starch to disc like structures and with increasing the AgNO3 concentration leads to the formation of fractals. This research could benefit battery technology where solid polymer membranes using starch is used.

Synthesis of thermal and chemical resistant oxygen barrier starch with reinforcement of nano silicon carbide.

PubMed

Dash, Satyabrata; Swain, Sarat K

2013-09-12

Starch/silicon carbide (starch/SiC) bionanocomposites were synthesized by solution method using different wt% of silicon carbide with starch matrix. The interaction between starch and silicon carbide was studied by Fourier transform infrared (FTIR) spectroscopy. The structure of the bionanocomposites was investigated by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). Thermal property of starch/SiC bionanocomposites was measured and a significant enhancement of thermal resistance was noticed. The oxygen barrier property of the composites was studied and a substantial reduction in permeability was observed as compared to the virgin starch. The reduction of oxygen permeability with enhancement of thermal stability of prepared bionanocomposites may enable the materials suitable for thermal resistant packaging and adhesive applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

All-natural bio-plastics using starch-betaglucan composites.

PubMed

Sagnelli, Domenico; Kirkensgaard, Jacob J K; Giosafatto, Concetta Valeria L; Ogrodowicz, Natalia; Kruczała, Krzysztof; Mikkelsen, Mette S; Maigret, Jean-Eudes; Lourdin, Denis; Mortensen, Kell; Blennow, Andreas

2017-09-15

Grain polysaccharides represent potential valuable raw materials for next-generation advanced and environmentally friendly plastics. Thermoplastic starch (TPS) is processed using conventional plastic technology, such as casting, extrusion, and molding. However, to adapt the starch to specific functionalities chemical modifications or blending with synthetic polymers, such as polycaprolactone are required (e.g. Mater-Bi). As an alternative, all-natural and compostable bio-plastics can be produced by blending starch with other polysaccharides. In this study, we used a maize starch (ST) and an oat β-glucan (BG) composite system to produce bio-plastic prototype films. To optimize performing conditions, we investigated the full range of ST:BG ratios for the casting (100:0, 75:25, 50:50, 25:75 and 0:100 BG). The plasticizer used was glycerol. Electron Paramagnetic Resonance (EPR), using TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) as a spin probe, showed that the composite films with high BG content had a flexible chemical environment. They showed decreased brittleness and improved cohesiveness with high stress and strain values at the break. Wide-angle X-ray diffraction displayed a decrease in crystallinity at high BG content. Our data show that the blending of starch with other natural polysaccharides is a noteworthy path to improve the functionality of all-natural polysaccharide bio-plastics systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of water volume and mixing time on physical properties of bread made from modified cassava starch-wheat composite flour

NASA Astrophysics Data System (ADS)

Srirejeki, S.; Manuhara, G. J.; Amanto, B. S.; Atmaka, W.; Laksono, P. W.

2018-03-01

Modification of cassava starch with soaking in the whey (by product on cheese production) resulted in changes of the flour characteristics. Adjustments of processing condition are important to be studied in the making of bread from modified cassava starch and wheat composite flour (30:70). This research aims to determine the effect of water volume and mixing time on the physical properties of the bread. The experimental design of this research was Completely Randomized Factorial Design (CRFD) with two factors which were water volume and mixing time. The variation of water volume significantly affected on bread height, dough volume, dough specific volume, and crust thickness. The variation of mixing time had a significant effect on the increase of dough volume and dough specific volume. The combination of water volume and mixing time had a significant effect on dough height, bread volume, bread specific volume, baking expansion, and weight loss.

Porous starch extracted from Chinese rice wine vinasse: characterization and adsorption properties.

PubMed

Li, Hongyan; Jiao, Aiquan; Wei, Benxi; Wang, Yong; Wu, Chunsen; Jin, Zhengyu; Tian, Yaoqi

2013-10-01

Chinese rice wine vinasse (the fermentation residue after removal of the crude wine or beer) contains 20-30% residual native starch. These starches are partly hydrolyzed by amylase and glucoamylase during rice wine fermentation, indicating that it is a potential source of porous starch, which is a value-added material. In the present study, morphological, short-range order, crystalline, and thermal studies were determined to characterize the structural and chemical properties of vinasse starch. The results showed that vinasse starch granule had a rough and porous shape and was much more ordered than native starch. Vinasse starch also could tolerate a higher temperature than native starch. The water and oil adsorptive capacities of vinasse starch were 1.89 and 4.14 times higher than that of native rice starch. These results suggest that vinasse is an effective and economical source of porous starch for using as adsorbent. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

Slow-Absorbing Modified Starch before and during Prolonged Cycling Increases Fat Oxidation and Gastrointestinal Distress without Changing Performance

PubMed Central

Baur, Daniel A.; Vargas, Fernanda de C. S.; Bach, Christopher W.; Garvey, Jordan A.; Ormsbee, Michael J.

2016-01-01

While prior research reported altered fuel utilization stemming from pre-exercise modified starch ingestion, the practical value of this starch for endurance athletes who consume carbohydrates both before and during exercise is yet to be examined. The purpose of this study was to determine the effects of ingesting a hydrothermally-modified starch supplement (HMS) before and during cycling on performance, metabolism, and gastrointestinal comfort. In a crossover design, 10 male cyclists underwent three nutritional interventions: (1) a commercially available sucrose/glucose supplement (G) 30 min before (60 g carbohydrate) and every 15 min during exercise (60 g∙h−1); (2) HMS consumed at the same time points before and during exercise in isocaloric amounts to G (Iso HMS); and (3) HMS 30 min before (60 g carbohydrate) and every 60 min during exercise (30 g·h−1; Low HMS). The exercise protocol (~3 h) consisted of 1 h at 50% Wmax, 8 × 2-min intervals at 80% Wmax, and 10 maximal sprints. There were no differences in sprint performance with Iso HMS vs. G, while both G and Iso HMS likely resulted in small performance enhancements (5.0%; 90% confidence interval = ±5.3% and 4.4%; ±3.2%, respectively) relative to Low HMS. Iso HMS and Low HMS enhanced fat oxidation (31.6%; ±20.1%; very likely (Iso); 20.9%; ±16.1%; likely (Low), and reduced carbohydrate oxidation (−19.2%; ±7.6%; most likely; −22.1%; ±12.9%; very likely) during exercise relative to G. However, nausea was increased during repeated sprints with ingestion of Iso HMS (17 scale units; ±18; likely) and Low HMS (18; ±14; likely) vs. G. Covariate analysis revealed that gastrointestinal distress was associated with reductions in performance with Low HMS vs. G (likely), but this relationship was unclear with Iso HMS vs. G. In conclusion, pre- and during-exercise ingestion of HMS increases fat oxidation relative to G. However, changes do not translate to performance improvements, possibly owing to HMS

Slow-Absorbing Modified Starch before and during Prolonged Cycling Increases Fat Oxidation and Gastrointestinal Distress without Changing Performance.

PubMed

Baur, Daniel A; Vargas, Fernanda de C S; Bach, Christopher W; Garvey, Jordan A; Ormsbee, Michael J

2016-06-25

While prior research reported altered fuel utilization stemming from pre-exercise modified starch ingestion, the practical value of this starch for endurance athletes who consume carbohydrates both before and during exercise is yet to be examined. The purpose of this study was to determine the effects of ingesting a hydrothermally-modified starch supplement (HMS) before and during cycling on performance, metabolism, and gastrointestinal comfort. In a crossover design, 10 male cyclists underwent three nutritional interventions: (1) a commercially available sucrose/glucose supplement (G) 30 min before (60 g carbohydrate) and every 15 min during exercise (60 g∙h(-1)); (2) HMS consumed at the same time points before and during exercise in isocaloric amounts to G (Iso HMS); and (3) HMS 30 min before (60 g carbohydrate) and every 60 min during exercise (30 g·h(-1); Low HMS). The exercise protocol (~3 h) consisted of 1 h at 50% Wmax, 8 × 2-min intervals at 80% Wmax, and 10 maximal sprints. There were no differences in sprint performance with Iso HMS vs. G, while both G and Iso HMS likely resulted in small performance enhancements (5.0%; 90% confidence interval = ±5.3% and 4.4%; ±3.2%, respectively) relative to Low HMS. Iso HMS and Low HMS enhanced fat oxidation (31.6%; ±20.1%; very likely (Iso); 20.9%; ±16.1%; likely (Low), and reduced carbohydrate oxidation (-19.2%; ±7.6%; most likely; -22.1%; ±12.9%; very likely) during exercise relative to G. However, nausea was increased during repeated sprints with ingestion of Iso HMS (17 scale units; ±18; likely) and Low HMS (18; ±14; likely) vs. G. Covariate analysis revealed that gastrointestinal distress was associated with reductions in performance with Low HMS vs. G (likely), but this relationship was unclear with Iso HMS vs. G. In conclusion, pre- and during-exercise ingestion of HMS increases fat oxidation relative to G. However, changes do not translate to performance improvements, possibly owing to HMS

Mechanical and barrier properties of maize starch-gelatin composite films: effects of amylose content.

PubMed

Wang, Kun; Wang, Wenhang; Ye, Ran; Xiao, Jingdong; Liu, Yaowei; Ding, Junsheng; Zhang, Shaojing; Liu, Anjun

2017-08-01

In order to obtain new reinforcing bio-fillers to improve the physicochemical properties of gelatin-based films, three types of maize starch, waxy maize starch (Ap), normal starch (Ns) and high-amylose starch (Al), were incorporated into gelatin film and the resulting film properties were investigated, focusing on the impact of amylose content. The thickness, opacity and roughness of gelatin film increased depending on the amylose content along with the starch concentration. The effects of the three starches on the mechanical properties of gelatin film were governed by amylose content, starch concentration as well as environmental relative humidity (RH). At 75% RH, the presence of Al and Ns in the gelatin matrix increased the film strength but decreased its elongation, while Ap exhibited an inverse effect. Starch addition decreased the oxygen permeability of the film, with the lowest value at 20% Al and Ns. All starches, notably at 30% content, led to a decrease in the water vapor permeability of the film at 90% RH, especially Ns starch. Furthermore, the starches improved the thermal stability of the film to some extent. Fourier transform infrared spectra indicated that some weak intermolecular interactions such as hydrogen bonding occurred between gelatin and starch. Moreover, a high degree of B-type crystallinity of starch was characterized in Gel-Al film by X-ray diffraction. Tailoring the properties of gelatin film by the incorporation of different types of maize starch provides the potential to extend its applications in edible food packaging. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Co-immobilization of glucoamylase and glucose oxidase for electrochemical sequential enzyme electrode for starch biosensor and biofuel cell.

PubMed

Lang, Qiaolin; Yin, Long; Shi, Jianguo; Li, Liang; Xia, Lin; Liu, Aihua

2014-01-15

A novel electrochemical sequential biosensor was constructed by co-immobilizing glucoamylase (GA) and glucose oxidase (GOD) on the multi-walled carbon nanotubes (MWNTs)-modified glassy carbon electrode (GCE) by chemical crosslinking method, where glutaraldehyde and bovine serum albumin was used as crosslinking and blocking agent, respectively. The proposed biosensor (GA/GOD/MWNTs/GCE) is capable of determining starch without using extra sensors such as Clark-type oxygen sensor or H2O2 sensor. The current linearly decreased with the increasing concentration of starch ranging from 0.005% to 0.7% (w/w) with the limit of detection of 0.003% (w/w) starch. The as-fabricated sequential biosensor can be applicable to the detection of the content of starch in real samples, which are in good accordance with traditional Fehling's titration. Finally, a stable starch/O2 biofuel cell was assembled using the GA/GOD/MWNTs/GCE as bioanode and laccase/MWNTs/GCE as biocathode, which exhibited open circuit voltage of ca. 0.53 V and the maximum power density of 8.15 μW cm(-2) at 0.31 V, comparable with the other glucose/O2 based biofuel cells reported recently. Therefore, the proposed biosensor exhibited attractive features such as good stability in weak acidic buffer, good operational stability, wide linear range and capable of determination of starch in real samples as well as optimal bioanode for the biofuel cell. Copyright © 2013 Elsevier B.V. All rights reserved.

Robust and biodegradable polymer of cassava starch and modified natural rubber.

PubMed

Riyajan, Sa-Ad

2015-12-10

The application of starch based materials for packaging purposes has attracted significant interest because they are both cheap and renewable resources. The study investigated the preparation and properties of a novel biopolymer sheet produced from a blend of maleated epoxidized natural rubber (MENR) and natural rubber-g-cassava starch (NR-g-CSt). The water resistance, toluene resistance and elongation at break of the polymer blend were enhanced after the addition of the MENR compared to pristine NR-g-CSt. The maximum tensile strength and thermal stability of the NR-g-CSt/MENR blend were found in the 100:50 NR-g-CSt:MENR blend. The novel films demonstrated good biodegradability in soil. Copyright © 2015 Elsevier Ltd. All rights reserved.

Brewing Science in the Chemistry Laboratory: A "Mashing" Investigation of Starch and Carbohydrates

ERIC Educational Resources Information Center

Pelter, Michael W.; McQuade, Jennifer

2005-01-01

The experiments that mimic the actual brewing process to explain the science to the nonscience majors is performed using malted barley as the source for both the starch and the amylase enzyme. The experiment introduces the concept of monitoring the progress of chemical reaction and was able to show the chemical breakdown of the starch to simple…

A comparison of corn fiber gum, hydrophobically modified starch, gum arabic and soybean soluble polysaccharide: interfacial dynamics, viscoelastic response at oil/water interfaces and emulsion stabilization mechanisms

USDA-ARS?s Scientific Manuscript database

The interfacial rheology of polysaccharide adsorption layers of corn fiber gum (CFG), octenyl succinate anhydride-modified starch (OSA-s), gum arabic (GA) and soybean soluble polysaccharides (SSPS) at the oil/water interface and their emulsifying properties in oil-in-water (O/W) emulsions were compa...

Chemically-modified cellulose paper as a microstructured catalytic reactor.

PubMed

Koga, Hirotaka; Kitaoka, Takuya; Isogai, Akira

2015-01-15

We discuss the successful use of chemically-modified cellulose paper as a microstructured catalytic reactor for the production of useful chemicals. The chemical modification of cellulose paper was achieved using a silane-coupling technique. Amine-modified paper was directly used as a base catalyst for the Knoevenagel condensation reaction. Methacrylate-modified paper was used for the immobilization of lipase and then in nonaqueous transesterification processes. These catalytic paper materials offer high reaction efficiencies and have excellent practical properties. We suggest that the paper-specific interconnected microstructure with pulp fiber networks provides fast mixing of the reactants and efficient transport of the reactants to the catalytically-active sites. This concept is expected to be a promising route to green and sustainable chemistry.

Functionality of maize, wheat, teff and cassava starches with stearic acid and xanthan gum.

PubMed

Maphalla, Thabelang Gladys; Emmambux, Mohammad Naushad

2016-01-20

Consumer concerns to synthetic chemicals have led to strong preference for 'clean' label starches. Lipid and hydrocolloids are food friendly chemicals. This study determines the effects of stearic acid and xanthan gum alone and in combination on the functionality of maize, wheat, teff and cassava starches. An increase in viscosity was observed for all starches with stearic acid and xanthan gum compared to the controls with cassava having the least increase. A further increase in viscosity was observed for the cereal starches with combination of stearic acid and xanthan gum. Stearic acid reduced retrogradation, resulting in soft textured pastes. Combination of stearic acid and xanthan gum reduced the formation of type IIb amylose-lipid complexes, syneresis, and hysteresis in cereal starches compared to stearic acid alone. A combination of stearic acid and xanthan gum produce higher viscosity non-gelling starches and xanthan gum addition increases physical stability to freezing and better structural recovery after shear. Copyright © 2015 Elsevier Ltd. All rights reserved.

Variation in ruminal in situ degradation of crude protein and starch from maize grains compared to in vitro gas production kinetics and physical and chemical characteristics.

PubMed

Seifried, Natascha; Steingaß, Herbert; Schipprack, Wolfgang; Rodehutscord, Markus

2016-10-01

The objectives of this study were (1) to evaluate in situ ruminal dry matter (DM), crude protein (CP) and starch degradation characteristics and in vitro gas production (GP) kinetics using a set of 20 different maize grain genotypes and (2) to predict the effective degradation (ED) of CP and starch from chemical and physical characteristics alone or in combination with in vitro GP measurements. Maize grains were characterised by different chemical and physical characteristics. Ruminal in situ degradation was measured in three lactating Jersey cows. Ground grains (sieve size: 2 mm) were incubated in bags for 1, 2, 4, 8, 16, 24, 48 and 72 h. Bag residues were analysed for CP and starch content. Degradation kinetics was determined and the ED of DM, CP and starch calculated using a ruminal passage rate of 5%/h and 8%/h. The GP of the grains (sieve size: 1 mm) was recorded after 2, 4, 6, 8, 12, 24, 48 and 72 h incubation in buffered rumen fluid and fitted to an exponential equation to determine GP kinetics. Correlations and stepwise multiple linear regressions were evaluated for the prediction of ED calculated for a passage rate of 5%/h (ED5) for CP (EDCP5) and starch (EDST5). The in situ parameters and ED5 varied widely between genotypes with average values (±SD) of 64% ± 4.2, 62% ± 4.1 and 65% ± 5.2 for ED5 of DM, EDCP5 and EDST5 and were on average 10 percentage points lower for a passage rate of 8%/h. Degradation rates varied between 4.8%/h and 7.4%/h, 4.1%/h and 6.5%/h and 5.3%/h and 8.9%/h for DM, CP and starch, respectively. These rates were in the same range as GP rates (6.0-8.3%/h). The EDCP5 and EDST5 were related to CP concentration and could be evaluated in detail using CP fractions and specific amino acids. In vitro GP measurements and GP rates correlated well with EDCP5 and EDST5 and predicted EDCP5 and EDST5 in combination with the chemical characteristics of the samples. Equations can be used to obtain quick and cost effective information

Organic amaranth starch: A study of its technological properties after heat-moisture treatment.

PubMed

Bet, Camila Delinski; de Oliveira, Cristina Soltovski; Colman, Tiago André Denck; Marinho, Marina Tolentino; Lacerda, Luiz Gustavo; Ramos, Augusto Pumacahua; Schnitzler, Egon

2018-10-30

Organic amaranth starch (Amaranthus caudatus) was studied after heat-moisture treatment (HMT) using different moisture contents and different times. The starch extracted by the aqueous method presented low lipid and protein content. After HMT, an increase in the thermal stability was identified. The onset and peak temperatures were higher with an increase in moisture content and the times used in the modification. The gelatinisation enthalpy varied due to the heterogeneity of the crystals formed after the structural reorganisation caused by HMT. The relative crystallinity was lower for the physically modified starches. An increase in the pasting temperature was accompanied by a decrease in the viscosity, setback and breakdown, which were proportional to the moisture and time used. The morphology of the HMT-modified samples was not altered; however, agglomerations were noted. Low levels of dispersion homogeneity and suspension stability were observed for the modified samples due to the strong presence of agglomerates. Published by Elsevier Ltd.

Properties and characteristics of dual-modified rice starch based biodegradable films.

PubMed

Woggum, Thewika; Sirivongpaisal, Piyarat; Wittaya, Thawien

2014-06-01

In this study, the dual-modified rice starch was hydroxypropylated with 6-12% of propylene oxide followed by crosslinking with 2% sodium trimetaphosphate (STMP) and a mixture of 2% STMP and 5% sodium tripolyphosphate (STPP). Increasing the propylene oxide concentrations in the DMRS yielded an increase in the molar substitution (MS) and degree of substitution (DS). However, the gelatinization parameters, paste properties, gel strength and paste clarity showed an inverse trend. The biodegradable films from the DMRS showed an increase the tensile strength, elongation at break and film solubility, while the transparency value decreased when the concentration of propylene oxide increased. However the water vapor permeability of the films did not significantly change with an increase in the concentration of propylene oxide. In addition, it was found that DMRS films crosslinked with 2% STMP demonstrated higher tensile strength, transparency value and lower water vapor permeability than the DMRS films crosslinked with a mixture of 2% STMP and 5% STPP. The XRD analysis of the DMRS films showed a decrease in crystallinity when the propylene oxide concentrations increased and the crystallinity of DMRS films with 2% STMP were higher than the DMRS films with a mixture of 2% STMP and 5% STPP. Copyright © 2014 Elsevier B.V. All rights reserved.

Poly(Lactic Acid) Filled with Cassava Starch-g-Soybean Oil Maleate

PubMed Central

Kiangkitiwan, Nopparut; Srikulkit, Kawee

2013-01-01

Poly(lactic acid), PLA, is a biodegradable polymer, but its applications are limited by its high cost and relatively poorer properties when compared to petroleum-based plastics. The addition of starch powder into PLA is one of the most promising efforts because starch is an abundant and cheap biopolymer. However, the challenge is the major problem associated with poor interfacial adhesion between the hydrophilic starch granules and the hydrophobic PLA, leading to poorer mechanical properties. In this paper, soybean oil maleate (SOMA) was synthesized by grafting soybean oil with various weight percents of maleic anhydride (MA) using dicumyl peroxide (DCP) as an initiator. Then, SOMA was employed for the surface modifying of cassava starch powder, resulting in SOMA-g-STARCH. The obtained SOMA-g-STARCH was mixed with PLA in various weight ratios using twin-screw extruder, resulting in PLA/SOMA-g-STARCH. Finally, the obtained PLA/SOMA-g-STARCH composites were prepared by a compression molding machines. The compatibility, thermal properties, morphology properties, and mechanical properties were characterized and evaluated. The results showed that the compatibility, surface appearance, and mechanical properties at 90 : 10 and 80 : 20 ratios of PLA/SOMA-g-STARCH were the best. PMID:24307883

Study of changes induced in thermal properties of starch by incorporating Ag nanoparticles

NASA Astrophysics Data System (ADS)

Meena, Sharma, Annu

2018-05-01

This report presents the study of thermal properties of starch and Ag-starch nanocomposite films fabricated via chemical reduction method followed by solution casting. Thermo gravimetric analysis was utilized to investigate the effect of varying concentration of Ag nanoparticles on thermal stability and activation energy of starch. Activation energy that is the energy required for initialization of degradation process of starch comes out to be 238.9 kJ/mol which decreases to a value of 174.6 kJ/mol for Ag-starch nanocomposite film containing 0.50 wt% of Ag nanoparticles. Moreover the thermal stability of starch increases with the increasing concentration of Ag nanoparticles.

Evaluation of a High Throughput Starch Analysis Optimised for Wood

PubMed Central

Bellasio, Chandra; Fini, Alessio; Ferrini, Francesco

2014-01-01

Starch is the most important long-term reserve in trees, and the analysis of starch is therefore useful source of physiological information. Currently published protocols for wood starch analysis impose several limitations, such as long procedures and a neutralization step. The high-throughput standard protocols for starch analysis in food and feed represent a valuable alternative. However, they have not been optimised or tested with woody samples. These have particular chemical and structural characteristics, including the presence of interfering secondary metabolites, low reactivity of starch, and low starch content. In this study, a standard method for starch analysis used for food and feed (AOAC standard method 996.11) was optimised to improve precision and accuracy for the analysis of starch in wood. Key modifications were introduced in the digestion conditions and in the glucose assay. The optimised protocol was then evaluated through 430 starch analyses of standards at known starch content, matrix polysaccharides, and wood collected from three organs (roots, twigs, mature wood) of four species (coniferous and flowering plants). The optimised protocol proved to be remarkably precise and accurate (3%), suitable for a high throughput routine analysis (35 samples a day) of specimens with a starch content between 40 mg and 21 µg. Samples may include lignified organs of coniferous and flowering plants and non-lignified organs, such as leaves, fruits and rhizomes. PMID:24523863

Biodegradation Behaviour of Thermoplastic Starch Films Derived from Tacca leontopetaloides Starch under Controlled Composting Condition

NASA Astrophysics Data System (ADS)

Amin, A. M. Mohd; Sauid, S. Mohd; Hamid, K. H. Ku; Musa, M.

2018-05-01

The biodegradation study of thermoplastic starch (TPS) films derived from Tacca leontopetaloides starch; namely TPS/GLY, TPS/ACE and TPS/BCHR were investigated under controlled composting conditions. A manual set-up test rig in laboratory scale was built according to ISO 14855-1: 2012. The biodegradation percentage was determined by measuring the amount of CO2 evolved using titration method and validated by automatic system (Arduino UNO System) that detected the CO2 evolved. After 45 days under controlled composting condition, results indicated that TPS/GLY degraded the fastest, followed by TPS/BCHR and the TPS/ACE had the slowest degradation. The biodegradation process of TPS/GLY, TPS/ACE and TPS/BCHR also exhibited two stages with different degradation speeds. From these results, it indicated that chemical modification of the TPS films by adding acetic acid and rice husk bio-char to the thermoplastic starch can have a major impact on the biodegradation rate and final biodegradation percentage.

Morphological, mechanical, barrier and properties of films based on acetylated starch and cellulose from barley.

PubMed

El Halal, Shanise Lisie Mello; Colussi, Rosana; Biduski, Bárbara; Evangelho, Jarine Amaral do; Bruni, Graziella Pinheiro; Antunes, Mariana Dias; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-01-01

Biodegradable films of native or acetylated starches with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. The tensile strength of the acetylated starch film was lower than those of the native starch film, without fibers. The addition of fibers increased the tensile strength and decreased the elongation and the moisture of native and acetylated starches films. The acetylated starch film showed higher water solubility when compared to native starch film. The addition of cellulose fibers reduced the water solubility of the acetylated starch film. The films reinforced with cellulose fiber exhibited a higher initial decomposition temperature and thermal stability. The mechanical, barrier, solubility, and thermal properties are factors which direct the type of the film application in packaging for food products. The films elaborated with acetylated starches of low degree of substitution were not effective in a reduction of the water vapor permeability. The addition of the cellulose fiber in acetylated and native starches films can contribute to the development of more resistant films to be applied in food systems that need to maintain their integrity. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Combination process method of lactic acid hydrolysis and hydrogen peroxide oxidation for cassava starch modification

NASA Astrophysics Data System (ADS)

Sumardiono, Siswo; Pudjihastuti, Isti; Budiyono, Hartanto, Hansen; Sophiana, Intan Clarissa

2017-05-01

Indonesia is one of the world's largest wheat importer, some research are conducted to find other carbohydrate sources which can replace wheat. Cassava is very easy to find and grown in tropical climates especially Indonesia. The research is focused on cassava starch modification as a substitute for wheat flour in order to reduce consumption of wheat flour. The aim of this research is to assess the effect of temperature, pH, and the concentration of H2O2 in modifying cassava starch which. The combination methods are lactic acid hydroxylation and hydrogen peroxide oxidation to improve baking expansion. The carboxyl group, carbonyl group, swelling power, starch solubility, and baking expansion of starch are analized and calculated. Results showed that the modified cassava starch can substitute wheat flour with optimum conditions process at a concentration of H2O2 is 1.5% w/w, oxidation temperature is 50°C, and pH is 3 by the value of swelling power is 6.82%, solubility is 0.02%, and baking expansion is 7.2 cm3/gram.

Structural modification in the formation of starch – silver nanocomposites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Begum, S. N. Suraiya; Ramasamy, Radha Perumal, E-mail: perumal.ramasamy@gmail.com; Aswal, V. K.

Polymer based nanocomposites have gained wide applications in field of battery technology. Starch is a naturally occurring polysaccharide with sustainable properties such as biodegradable, non toxic, excellent film forming capacity and it also act as reducing agent for the metal nanoparticles. In our research various concentration of silver nitrate (AgNO{sub 3}) was added to the starch solution and films were obtained using solution casting method. Surface electron microscope (SEM) of the films shows modifications depending upon the concentration of AgNO{sub 3}. Small angle neutron scattering (SANS) analysis showed that addition of silver nitrate modifies the starch to disc like structuresmore » and with increasing the AgNO{sub 3} concentration leads to the formation of fractals. This research could benefit battery technology where solid polymer membranes using starch is used.« less

Artificial specific binders directly recovered from chemically modified nucleic acid libraries.

PubMed

Kasahara, Yuuya; Kuwahara, Masayasu

2012-01-01

Specific binders comprised of nucleic acids, that is, RNA/DNA aptamers, are attractive functional biopolymers owing to their potential broad application in medicine, food hygiene, environmental analysis, and biological research. Despite the large number of reports on selection of natural DNA/RNA aptamers, there are not many examples of direct screening of chemically modified nucleic acid aptamers. This is because of (i) the inferior efficiency and accuracy of polymerase reactions involving transcription/reverse-transcription of modified nucleotides compared with those of natural nucleotides, (ii) technical difficulties and additional time and effort required when using modified nucleic acid libraries, and (iii) ambiguous efficacies of chemical modifications in binding properties until recently; in contrast, the effects of chemical modifications on biostability are well studied using various nucleotide analogs. Although reports on the direct screening of a modified nucleic acid library remain in the minority, chemical modifications would be essential when further functional expansion of nucleic acid aptamers, in particular for medical and biological uses, is considered. This paper focuses on enzymatic production of chemically modified nucleic acids and their application to random screenings. In addition, recent advances and possible future research are also described.

Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics

PubMed Central

Xu, Xuan; Dechesne, Annemarie; Visser, Richard G. F.; Trindade, Luisa M.

2016-01-01

Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines. PMID:27911907

Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics.

PubMed

Xu, Xuan; Dechesne, Annemarie; Visser, Richard G F; Trindade, Luisa M

2016-01-01

Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines.

Starch hydrogels: The influence of the amylose content and gelatinization method.

PubMed

Biduski, Bárbara; Silva, Wyller Max Ferreria da; Colussi, Rosana; Halal, Shanise Lisie de Mello El; Lim, Loong-Tak; Dias, Álvaro Renato Guerra; Zavareze, Elessandra da Rosa

2018-07-01

Gelatinization and retrogradation, influenced by amylose and amylopectin ratio, are important characteristics for starch hydrogels elaboration. The objective of this study was to evaluate the influence of amylose content and the gelatinization method on the physicochemical characteristics of native and cross-linked rice starch hydrogels. The native and cross-linked starches were gelatinized with heating or alkaline solution, added polyvinyl alcohol, frozen and then freeze-dried. The cross-linked starch had a low final viscosity (101.38 RVU), which made the heat-induced gelatinized hydrogel readily disintegrated in water. However, modified starch hydrogels obtained by alkaline-induced gelatinization resulted in a more rigid structure than the native starch hydrogels. In addition, the starch sample with high amylose content had lower water absorption (322.2%) due to the greater stiffness of the hydrogel structure that resisted swelling. The alkaline-gelatinization resulted in stiffer hydrogels with lower water absorption (322.2 to 534.8%), while the heat-gelatinized behaved as a superabsorbent (658.7 to 1068.5%). The variability of the hydrogels properties of this study can enable a range of applications due to different amylose contents and gelatinization methods. Copyright © 2018 Elsevier B.V. All rights reserved.

Chemically modified graphene based supercapacitors for flexible and miniature devices

NASA Astrophysics Data System (ADS)

Ghosh, Debasis; Kim, Sang Ouk

2015-09-01

Rapid progress in the portable and flexible electronic devises has stimulated supercapacitor research towards the design and fabrication of high performance flexible devices. Recent research efforts for flexible supercapacitor electrode materials are highly focusing on graphene and chemically modified graphene owing to the unique properties, including large surface area, high electrical and thermal conductivity, excellent mechanical flexibility, and outstanding chemical stability. This invited review article highlights current status of the flexible electrode material research based on chemically modified graphene for supercapacitor application. A variety of electrode architectures prepared from chemically modified graphene are summarized in terms of their structural dimensions. Novel prototypes for the supercapacitor aiming at flexible miniature devices, i.e. microsupercapacitor with high energy and power density are highlighted. Future challenges relevant to graphene-based flexible supercapacitors are also suggested. [Figure not available: see fulltext.

Structural, morphological, and physicochemical properties of acetylated high-, medium-, and low-amylose rice starches.

PubMed

Colussi, Rosana; Pinto, Vania Zanella; El Halal, Shanise Lisie Mello; Vanier, Nathan Levien; Villanova, Franciene Almeida; Marques E Silva, Ricardo; da Rosa Zavareze, Elessandra; Dias, Alvaro Renato Guerra

2014-03-15

The high-, medium-, and low-amylose rice starches were isolated by the alkaline method and acetylated by using acetic anhydride for 10, 30, and 90 min of reaction. The degree of substitution (DS), the Fourier-transformed infrared spectroscopy (FTIR), the X-ray diffractograms, the thermal, morphological, and pasting properties, and the swelling power and solubility of native and acetylated starches were evaluated. The DS of the low-amylose rice starch was higher than the DS of the medium- and the high-amylose rice starches. The introduction of acetyl groups was confirmed by FTIR spectroscopy. The acetylation treatment reduced the crystallinity, the viscosity, the swelling power, and the solubility of rice starch; however, there was an increase in the thermal stability of rice starch modified by acetylation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Starch poisoning

MedlinePlus

Cooking starch poisoning; Laundry starch poisoning ... Cooking and laundry starch are both made from vegetable products, most commonly: Corn Potatoes Rice Wheat Both are usually considered nonpoisonous (nontoxic), but ...

Effect of high pressure on rheological and thermal properties of quinoa and maize starches.

PubMed

Li, Guantian; Zhu, Fan

2018-02-15

Quinoa starch has small granules with relatively low gelatinization temperatures and amylose content. High hydrostatic pressure (HHP) is a non-thermal technique for food processing. In this study, effects of HHP up to 600MPa on physical properties of quinoa starch were studied and compared with those of a normal maize starch. Both starches gelatinized at 500 and 600MPa. The pressure of 600MPa completely gelatinized quinoa starch as revealed by thermal analysis. Dynamic rheological analysis showed that HHP improved the gel stability of both starches during cooling. HHP had little effects on amylopectin recrystallization and gel textural properties of starch. Overall, quinoa starch was more susceptible to HHP than maize starch. The effects of HHP on some rheological properties such as frequency dependence were different between these two types of starches. The differences could be attributed to the different composition, granular and chemical structures of starch, and the presence of granule remnants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fusion proteins comprising the catalytic domain of mutansucrase and a starch-binding domain can alter the morphology of amylose-free potato starch granules during biosynthesis.

PubMed

Nazarian Firouzabadi, Farhad; Kok-Jacon, Géraldine A; Vincken, Jean-Paul; Ji, Qin; Suurs, Luc C J M; Visser, Richard G F

2007-10-01

It has been shown previously that mutan can be co-synthesized with starch when a truncated mutansucrase (GtfICAT) is directed to potato tuber amyloplasts. The mutan seemed to adhere to the isolated starch granules, but it was not incorporated in the starch granules. In this study, GtfICAT was fused to the N- or C-terminus of a starch-binding domain (SBD). These constructs were introduced into two genetically different potato backgrounds (cv. Kardal and amf), in order to bring GtfICAT in more intimate contact with growing starch granules, and to facilitate the incorporation of mutan polymers in starch. Fusion proteins of the appropriate size were evidenced in starch granules, particularly in the amf background. The starches from the various GtfICAT/SBD transformants seemed to contain less mutan than those from transformants with GtfICAT alone, suggesting that the appended SBD might inhibit the activity of GtfICAT in the engineered fusion proteins. Scanning electron microscopy showed that expression of SBD-GtfICAT resulted in alterations of granule morphology in both genetic backgrounds. Surprisingly, the amf starches containing SBD-GtfICAT had a spongeous appearance, i.e., the granule surface contained many small holes and grooves, suggesting that this fusion protein can interfere with the lateral interactions of amylopectin sidechains. No differences in physico-chemical properties of the transgenic starches were observed. Our results show that expression of granule-bound and "soluble" GtfICAT can affect starch biosynthesis differently.

Influence of resistant starch and slowly digestible starch on rice texture.

USDA-ARS?s Scientific Manuscript database

Rice, comprised mainly of starch, serves as a significant source of caloric energy world-wide, therefore differences in starch digestibility are important to human health. Rice starch consists of three forms based on digestibility, rapidly digestible starch (RDS), slowly digestible starch (SDS), and...

Bio-composites of cassava starch-green coconut fiber: part II-Structure and properties.

PubMed

Lomelí-Ramírez, María Guadalupe; Kestur, Satyanarayana G; Manríquez-González, Ricardo; Iwakiri, Setsuo; de Muniz, Graciela Bolzon; Flores-Sahagun, Thais Sydenstricker

2014-02-15

Development of any new material requires its complete characterization to find potential applications. In that direction, preparation of bio-composites of cassava starch containing up to 30 wt.% green coconut fibers from Brazil by thermal molding process was reported earlier. Their characterization regarding physical and tensile properties of both untreated and treated matrices and their composites were also reported. Structural studies through FTIR and XRD and thermal stability of the above mentioned composites are presented in this paper. FT-IR studies revealed decomposition of components in the matrix; the starch was neither chemically affected nor modified by either glycerol or the amount of fiber. XRD studies indicated increasing crystallinity of the composites with increasing amount of fiber content. Thermal studies through TGA/DTA showed improvement of thermal stability with increasing amount of fiber incorporation, while DMTA showed increasing storage modulus, higher glass transition temperature and lower damping with increasing fiber content. Improved interfacial bonding between the matrix and fibers could be the cause for the above results. Copyright © 2013 Elsevier Ltd. All rights reserved.

siRNAmod: A database of experimentally validated chemically modified siRNAs.

PubMed

Dar, Showkat Ahmad; Thakur, Anamika; Qureshi, Abid; Kumar, Manoj

2016-01-28

Small interfering RNA (siRNA) technology has vast potential for functional genomics and development of therapeutics. However, it faces many obstacles predominantly instability of siRNAs due to nuclease digestion and subsequently biologically short half-life. Chemical modifications in siRNAs provide means to overcome these shortcomings and improve their stability and potency. Despite enormous utility bioinformatics resource of these chemically modified siRNAs (cm-siRNAs) is lacking. Therefore, we have developed siRNAmod, a specialized databank for chemically modified siRNAs. Currently, our repository contains a total of 4894 chemically modified-siRNA sequences, comprising 128 unique chemical modifications on different positions with various permutations and combinations. It incorporates important information on siRNA sequence, chemical modification, their number and respective position, structure, simplified molecular input line entry system canonical (SMILES), efficacy of modified siRNA, target gene, cell line, experimental methods, reference etc. It is developed and hosted using Linux Apache MySQL PHP (LAMP) software bundle. Standard user-friendly browse, search facility and analysis tools are also integrated. It would assist in understanding the effect of chemical modifications and further development of stable and efficacious siRNAs for research as well as therapeutics. siRNAmod is freely available at: http://crdd.osdd.net/servers/sirnamod.

Effects of granule swelling on starch saccharification by granular starch hydrolyzing enzyme.

PubMed

Li, Zhaofeng; Cai, Liming; Gu, Zhengbiao; Shi, Yong-Cheng

2014-08-13

The effects of granule swelling on enzymatic saccharification of normal corn starch by granular starch hydrolyzing enzyme were investigated. After swelling, Km values for the saccharification of granular starch decreased compared with native granular starch, indicating that granule swelling caused granular starch hydrolyzing enzyme to have higher affinity for starch granules. The partial swelling of starch granules enhanced starch saccharification. Furthermore, the enhancement at an earlier stage of enzymatic reaction was much more significant than that at later stages. For granular starch pretreated at 67.5 °C for 30 min, conversions to glucose after incubation with the enzyme at 32 °C for 4 and 24 h were approximately 3-fold and 26% higher than for native granular starch, respectively. As a result, proper heat pretreatment of granular starch before simultaneous saccharification and fermentation has great potential to facilitate industrial production of ethanol by use of granular starch hydrolyzing enzyme.

Swelling Kinetics of Waxy Maize Starch

NASA Astrophysics Data System (ADS)

Desam, Gnana Prasuna Reddy

Starch pasting behavior greatly influences the texture of a variety of food products such as canned soup, sauces, baby foods, batter mixes etc. The annual consumption of starch in the U.S. is 3 million metric tons. It is important to characterize the relationship between the structure, composition and architecture of the starch granules with its pasting behavior in order to arrive at a rational methodology to design modified starch of desirable digestion rate and texture. In this research, polymer solution theory was applied to predict the evolution of average granule size of starch at different heating temperatures in terms of its molecular weight, second virial coefficient and extent of cross-link. Evolution of granule size distribution of waxy native maize starch when subjected to heating at constant temperatures of 65, 70, 75, 80, 85 and 90 C was characterized using static laser light scattering. As expected, granule swelling was more pronounced at higher temperatures and resulted in a shift of granule size distribution to larger sizes with a corresponding increase in the average size by 100 to 120% from 13 mum to 25-28 mum. Most of the swelling occurred within the first 10 min of heating. Pasting behavior of waxy maize at different temperatures was also characterized from the measurements of G' and G" for different heating times. G' was found to increase with temperature at holding time of 2 min followed by its decrease at larger holding times. This behavior is believed to be due to the predominant effect of swelling at small times. However, G" was insensitive to temperature and holding times. The structure of waxy maize starch was characterized by cryoscanning electron microscopy. Experimental data of average granule size vs time at different temperatures were compared with model predictions. Also the Experimental data of particle size distribution vs particle size at different times and temperatures were compared with model predictions.

Preparation of potato starch microfibers obtained by electro wet spinning

NASA Astrophysics Data System (ADS)

Cárdenas, W.; Gómez-Pachon, E. Y.; Muñoz, E.; Vera-Graziano, R.

2016-07-01

Starch is one of the most abundant biopolymer in nature. It has been primarily used as a thickener in the food industry. Starch is found in greater amounts in the potato tubers, which is one of the largest food productions in the region of Boyacá-Colombia. Thus, potatoes are a viable source of starch. The main objective of this study is the preparation and characterization of native starch's microfiber by electro wet-spinning technique. The parameters that were changed for each treatment were as follows: the amount of potential applied to the solution, the distance between the needle and the collector and the rate of injection of the solution in order to determine the physical and chemical properties of the membranes, conformed by potatoes starch microfiber. Diverse instrumental analysis techniques were applied. They were: Scanning Electron Microscopy (SEM) to determine the morphologies and diameters of microfibers, Fourier Transform Infrared Spectroscopy (FTIR) to determine the chemical changes, Thermogravimetric Analysis (TGA) and Differential Calorimetry Scanning (DSC) to obtain the thermal transitions and the temperatures of useful. The microfibers were analysed in order to determine their structural properties and thus define the range of application. In conclusion, potatoes starch microfibers were obtained with average diameters of 15, 17, 23 and 25 micrometres, besides the fibers presented a degradation temperature of 304 °C, indicating that fibers are available with diameters of small scale, with good thermal properties. This study will enable the implementation of the microfibers to obtain bio packaging for food products and other applications.

Physicochemical properties of quinoa flour as affected by starch interactions.

PubMed

Li, Guantian; Zhu, Fan

2017-04-15

There has been growing interest in whole grain quinoa flour for new product development due to the unique nutritional benefits. The quality of quinoa flour is much determined by the properties of its major component starch as well as non-starch components. In this study, composition and physicochemical properties of whole grain flour from 7 quinoa samples have been analyzed. Flour properties have been correlated to the flour composition and the properties of isolated quinoa starches through chemometrics. Great variations in chemical composition, swelling power, water soluble index, enzyme susceptibility, pasting, gel texture, and thermal properties of the flour have been observed. Correlation analysis showed that thermal properties and enzyme susceptibility of quinoa flour are highly influenced by the starch. Interactions of starch with non-starch components, including lipids, protein, dietary fibre, phenolics, and minerals, greatly impacted the flour properties. For example, peak gelatinization temperature of the flour is positively correlated to that of the starch (r=0.948, p<0.01) and negatively correlated to the lipid content (r=-0.951, p<0.01). Understanding the roles of starch and other components in physicochemical properties of quinoa flour provides a basis for better utilization of this specialty crop. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of mineral elements on physicochemical properties of oxidised starches and generation of free radicals.

PubMed

Pietrzyk, Sławomir; Fortuna, Teresa; Królikowska, Karolina; Rogozińska, Ewelina; Labanowska, Maria; Kurdziel, Magdalena

2013-09-12

The objective of this study was to determine the effect of enrichment of oxidised starches with mineral compounds on their physicochemical properties and capability for free radical generation. Potato and spelt wheat starches were oxidised with sodium hypochlorite and, afterwards, modified with ions of potassium, magnesium and iron. The modified starches were analysed for: content of mineral elements, colour parameters (L*a*b*), water binding capacity solubility in water at temperature of 50 and 80 °C, and susceptibility to enzymatic hydrolysis with α-amylase. In addition, thermodynamic characteristics of gelatinisation was determined by differential scanning calorimetry (DSC), and the number and character of thermally generated free radicals was assayed using electron paramagnetic resonance (EPR). Based on the results achieved, it was concluded that the quantity of incorporated minerals and changes in the assayed physicochemical parameters depended not only on the botanical type of starch but also on the type of the incorporated mineral element. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physicochemical properties, in-vitro digestibility and structural elucidation of RS4 from rice starch.

PubMed

Ashwar, Bilal Ahmad; Gani, Adil; Shah, Asima; Masoodi, Farooq Ahmad

2017-12-01

Starches extracted from four different rice cultivars were phosphorylated by using STMP/STPP to make modified food starches with high contents of type 4 resistant starch (RS4). The results revealed 10- fold improvement in RS4 content by the phosphorylation of starch. The phosphorus % and DS values of rice starches ranged from 0.33 to 0.35, and 0.016 to 0.018, respectively. FT-IR spectroscopy showed reduction of OH stretching band at 3290cm-1 and the appearance of PO at 1244-1266cm-1 which confirms crosslinking of starch with STMP/STPP. Phosphorylation was found to increase water absorption capacity, oil absorption capacity, bile-acid binding and lightness, whereas amylose content, swelling power, solubility index and light transmittance were decreased with phosphorylation. DSC analyses revealed increase in thermal transition temperatures of the crosslinked starches which suggests that the application of STMP/STPP as a crosslinker can improve the integrality and stability of starch. SEM micro-graphs revealed that phosphorylated rice starch granules retained their integrity, while some fissures appeared on the surface of some granules. XRD analysis revealed decreased crystallinity of RS4 rice starches. Copyright © 2017 Elsevier B.V. All rights reserved.

Multi-scale structure, pasting and digestibility of heat moisture treated red adzuki bean starch.

PubMed

Wang, Hongwei; Wang, Zhaoyuan; Li, Xiaoxi; Chen, Ling; Zhang, Binjia

2017-09-01

The pasting and digestibility of a red adzuki bean starch were simultaneously modulated by heat-moisture treatment (HMT) through altering the multi-scale structure. HMT, especially at high moisture content, could disrupt the granule integrity, semicrystalline lamellae, molecular order (crystallites) and molecular chains. Also, certain rearrangement of starch molecules occurred to form ordered structures with increased thermal stability as shown by DSC. This concomitant disordering and reassembly in the multi-scale structure converted the fractions of resistant starch (RS) and rapidly digestible starch (RDS) into that of slowly digestible starch (SDS). Furthermore, the emergence of thermally-stable orders increased the pasting temperature but suppressed the swelling of granules during heating. Hence, HMT-modified red adzuki starch may serve as a potential thickener/gelling agent with slow digestion rate for various foods. Copyright © 2017. Published by Elsevier B.V.

Internal structure of normal maize starch granules revealed by chemical surface gelatinization.

PubMed

Pan, D D; Jane, J I

2000-01-01

Normal maize starch was fractionated into two sizes: large granules with diameters more than 5 microns and small granules with diameters less than 5 microns. The large granules were surface gelatinized by treating them with an aqueous LiCl solution (13 M) at 22-23 degrees C. Surface-gelatinized remaining granules were obtained by mechanical blending, and gelatinized surface starch was obtained by grinding with a mortar and a pestle. Starches of different granular sizes and radial locations, obtained after different degrees of surface gelatinization, were subjected to scanning electron microscopy, iodine potentiometric titration, gel-permeation chromatography, and amylopectin branch chain length analysis. Results showed that the remaining granules had a rough surface with a lamella structure. Amylose was more concentrated at the periphery than at the core of the granule. Amylopectin had longer long B-chains at the core than at the periphery of the granule. Greater proportions of the long B-chains were present at the core than at the periphery of the granule.

End-of-life of starch-polyvinyl alcohol biopolymers.

PubMed

Guo, M; Stuckey, D C; Murphy, R J

2013-01-01

This study presents a life cycle assessment (LCA) model comparing the waste management options for starch-polyvinyl alcohol (PVOH) biopolymers including landfill, anaerobic digestion (AD), industrial composting and home composting. The ranking of biological treatment routes for starch-PVOH biopolymer wastes depended on their chemical compositions. AD represents the optimum choice for starch-PVOH biopolymer containing N and S elements in global warming potential (GWP(100)), acidification and eutrophication but not on the remaining impact categories, where home composting was shown to be a better option due to its low energy and resource inputs. For those starch-PVOH biopolymers with zero N and S contents home composting delivered the best environmental performance amongst biological treatment routes in most impact categories (except for GWP(100)). The landfill scenario performed generally well due largely to the 100-year time horizon and efficient energy recovery system modeled but this good performance is highly sensitive to assumptions adopted in landfill model. Copyright © 2012 Elsevier Ltd. All rights reserved.

A comparison of the stability of beverage cloud emulsions formulated with different gum acacia- and starch-based emulsifiers.

PubMed

Reiner, S J; Reineccius, G A; Peppard, T L

2010-06-01

The performance of several hydrocolloids (3 gum acacias, 1 modified gum acacia, and 3 modified starches) in stabilizing beverage emulsions and corresponding model beverages was investigated employing different core materials, emulsifier usage levels, and storage temperatures. Concentrated emulsions were prepared using orange terpenes or Miglyol 812 (comprising medium-chain triglycerides, MCT) weighted 1:1 with ester gum, stored at 25 or 35 degrees C, and analyzed on days 0, 1, and 3. On day 3, model beverages were made from each emulsion, stored at both temperatures, and analyzed weekly for 4 wk. Stability of concentrated emulsions was assessed by measuring mean particle size and by visual observations of ringing; beverage stability was judged similarly and also by loss of turbidity. Particle size measurements showed concentrated emulsions containing gum acacia or modified gum acacia with either core material were stable over 3 d storage at both temperatures whereas those made with modified starches were not, destabilization being faster at 35 degrees C. Beverages based on orange terpenes, in contrast to Miglyol, yielded smaller mean particle sizes, both on manufacture and during storage, regardless of hydrocolloid used. Visual observations of ringing generally supported this finding. Modified gum acacia was evaluated at both recommended and higher usage levels, stability increasing in the latter case. In general, all gum acacia and modified gum acacia emulsifiers were superior in stability to those based on modified starches, at either temperature, for orange terpene-based beverages. In Miglyol-based beverages, similar results were seen, except 1 modified starch performed as well as the gum acacia products.

Overexpression of STARCH BRANCHING ENZYME II increases short-chain branching of amylopectin and alters the physicochemical properties of starch from potato tuber.

PubMed

Brummell, David A; Watson, Lyn M; Zhou, Jun; McKenzie, Marian J; Hallett, Ian C; Simmons, Lyall; Carpenter, Margaret; Timmerman-Vaughan, Gail M

2015-04-29

amylopectin branching pattern. This work reports the first time that overexpression of SBEII has been achieved in a non-cereal plant. The data show that overexpression of SBEII using a simple single-intron hybrid intragene is an effective way to modify potato starch physicochemical properties, and indicate that an increased ratio of short to long amylopectin branches produces commercially beneficial changes in starch properties such as reduced gelatinisation temperature, reduced viscosity and increased swelling volume.

Eukaryotic starch degradation: integration of plastidial and cytosolic pathways.

PubMed

Fettke, Joerg; Hejazi, Mahdi; Smirnova, Julia; Höchel, Erik; Stage, Marion; Steup, Martin

2009-01-01

Starch is an important plant product widely used as a nutrient, as a source of renewable energy, and for many technological applications. In plants, starch is the almost ubiquitous storage carbohydrate whereas most heterotrophic prokaryotes and eukaryotes rely on glycogen. Despite close similarities in basic chemical features, starch and glycogen differ in both structural and physicochemical properties. Glycogen is a hydrosoluble macromolecule with evenly distributed branching points. Starch exists as a water-insoluble particle having a defined (and evolutionary conserved) internal structure. The biochemistry of starch requires the co-operation of up to 40 distinct (iso)enzymes whilst approximately 10 (iso)enzymes permit glycogen metabolism. The biosynthesis and degradation of native starch include the transition of carbohydrates from the soluble to the solid phase and vice versa. In this review, two novel aspects of the eukaryotic plastidial starch degradation are discussed: Firstly, biochemical reactions that take place at the surface of particulate glucans and mediate the phase transition of carbohydrates. Secondly, processes that occur downstream of the export of starch-derived sugars into the cytosol. Degradation of transitory starch mainly results in the formation of neutral sugars, such as glucose and maltose, that are transported into the cytosol via the respective translocators. The cytosolic metabolism of the neutral sugars includes the action of a hexokinase, a phosphoglucomutase, and a transglucosidase that utilizes high molecular weight glycans as a transient glucosyl acceptor or donor. Data are included on the transglucosidase (disproportionating isozyme 2) in Cyanophora paradoxa that accumulates storage carbohydrates in the cytosol rather than in the plastid.

Slow glucose release property of enzyme-synthesized highly branched maltodextrins differs among starch sources.

PubMed

Kittisuban, Phatcharee; Lee, Byung-Hoo; Suphantharika, Manop; Hamaker, Bruce R

2014-07-17

Seven types of starch (waxy corn, normal corn, waxy rice, normal rice, waxy potato, normal potato, and tapioca) were selected to produce slowly digestible maltodextrins by enzymatic modification using a previously developed procedure. Branching enzyme (BE) alone and in combination with β-amylase (BA) were used to increase the amount of α-1,6 branching points, which are slowly hydrolyzed by mucosal α-glucosidases in the small intestine. The enzymatic treatments of all starches resulted in a reduction of the debranched linear chain length distribution and weight-average molecular weight. After α-amylolysis of the enzymatically synthesized-maltodextrins, the proportion of branched α-limit dextrins increased, and consequently a reduction in rate of glucose release by rat intestinal α-glucosidases in vitro. Among the samples, enzyme-modified waxy starches had a more pronounced effect on an increase in the slow digestion property than normal starches. These enzyme-modified maltodextrins show potential as novel functional foods by slowing digestion rate to attain extended glucose release. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of alpha-amylase reaction mechanisms on analysis of resistant-starch contents.

PubMed

Moore, Samuel A; Ai, Yongfeng; Chang, Fengdan; Jane, Jay-lin

2015-01-22

This study aimed to understand differences in the resistant starch (RS) contents of native and modified starches obtained using two standard methods of RS content analysis: AOAC Method 991.43 and 2002.02. The largest differences were observed in native potato starch, cross-linked wheat distarch phosphate, and high-amylose corn starch stearic-acid complex (RS5) between using AOAC Method 991.43 with Bacillus licheniformis α-amylase (BL) and AOAC Method 2002.02 with porcine pancreatic α-amylase (PPA). To determine possible reasons for these differences, we hydrolyzed raw-starch granules with BL and PPA with equal activity at pH 6.9 and 37°C for up to 84 h and observed the starch granules displayed distinct morphological differences after the hydrolysis. Starches hydrolyzed by BL showed erosion on the surface of the granules; those hydrolyzed by PPA showed pitting on granule surfaces. These results suggested that enzyme reaction mechanisms, including the sizes of the binding sites and the reaction patterns of the two enzymes, contributed to the differences in the RS contents obtained using different methods of RS analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Physicochemical properties of starches isolated from pumpkin compared with potato and corn starches.

PubMed

Przetaczek-Rożnowska, Izabela

2017-08-01

The aim of the study was to characterize the selected physicochemical, thermal and rheological properties of pumpkin starches and compared with the properties of potato and corn starches used as control samples. Pumpkin starches could be used in the food industry as a free gluten starch. Better thermal and rheological properties could contribute to reduce the costs of food production. The syneresis of pumpkin starches was similar to that of potato starch but much lower than that for corn starch. Pasting temperatures of pumpkin starches were lower by 17-21.7°C and their final viscosities were over 1000cP higher than corn paste, but were close to the values obtained for potato starch. The thermodynamic characteristic showed that the transformation temperatures of pumpkin starches were lower than those measured for control starches. A level of retrogradation was much lower in pumpkin starch pastes (32-48%) than was in the case of corn (59%) or potato (77%) starches. The pumpkin starches gels were characterized by a much greater hardness, cohesiveness and chewiness, than potato or corn starches gels. Copyright © 2017 Elsevier B.V. All rights reserved.

Starch: chemistry, microstructure, processing and enzymatic degradation

USDA-ARS?s Scientific Manuscript database

Starch is recognized as one of the most abundant and important commodities containing value added attributes for a vast number of industrial applications. Its chemistry, structure, property and susceptibility to various chemical, physical and enzymatic modifications offer a high technological value ...

Influence of galactooligosaccharides and modified waxy maize starch on some attributes of yogurt.

PubMed

Prasad, Laxmi N; Sherkat, Frank; Shah, Nagendra P

2013-01-01

This study examined the influence of galactooligosaccharides (GOS) and modified waxy maize starch (MWMS) addition on the growth of starter cultures, and syneresis and firmness of low-fat yogurt during storage for 28 d at 4 °C. The control yogurt (CY) was prepared without any prebiotics. Incorporation of 2.0% (w/v) GOS improved the growth of L. delbrueckii ssp. bulgaricus ATCC 11842 resulting in a shorter fermentation time. There was a significant (P < 0.05) increase in proteolysis in yogurt made with GOS (GOSY) as measured by absorbance value (0.728). Addition of GOS resulted in higher (P < 0.05) concentration of lactic and acetic acids in comparison with that of MWMSY and the CY up to day 14, thereafter, the product showed a decrease in lactic acid content in all 3 batches until the end of storage. The level of syneresis was the lowest (2.14%) in MWMSY as compared with that of GOSY (2.35%) and CY (2.53%). There was no statistically significant (P > 0.05) difference in the firmness among the 3 types of yogurt. © 2012 Institute of Food Technologists®

Development of corn starch based green composites reinforced with Saccharum spontaneum L fiber and graft copolymers--evaluation of thermal, physico-chemical and mechanical properties.

PubMed

Kaith, B S; Jindal, R; Jana, A K; Maiti, M

2010-09-01

In this paper, corn starch based green composites reinforced with graft copolymers of Saccharum spontaneum L. (Ss) fiber and methyl methacrylates (MMA) and its mixture with acrylamide (AAm), acrylonitrile (AN), acrylic acid (AA) were prepared. Resorcinol-formaldehyde (Rf) was used as the cross-linking agent in corn starch matrix and different physico-chemical, thermal and mechanical properties were evaluated. The matrix and composites were found to be thermally more stable than the natural corn starch backbone. Further the matrix and composites were subjected for biodegradation studies through soil composting method. Different stages of biodegradation were evaluated through FT-IR and scanning electron microscopic (SEM) techniques. S. spontaneum L fiber-reinforced composites were found to exhibit better tensile strength. On the other hand Ss-g-poly (MMA) reinforced composites showed maximum compressive strength and wear resistance than other graft copolymers reinforced composite and the basic matrix. (c) 2010 Elsevier Ltd. All rights reserved.

Composition and physical properties of starch in microgravity-grown plants.

PubMed

Kuznetsov, O A; Brown, C S; Levine, H G; Piastuch, W C; Sanwo-Lewandowski, M M; Hasenstein, K H

2001-01-01

The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Composition and physical properties of starch in microgravity-grown plants

NASA Technical Reports Server (NTRS)

Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.; Sager, J. C. (Principal Investigator)

2001-01-01

The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate.

PubMed

Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

2016-01-01

High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed.

Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate

PubMed Central

Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

2016-01-01

High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed. PMID:27219066

Effect of resistant starch RS4 added to the high-fat diets on selected biochemical parameters in Wistar rats.

PubMed

Bronkowska, Monika; Orzeł, Dagmara; Łoźna, Karolina; Styczyńska, Marzena; Biernat, Jadwiga; Gryszkin, Artur; Zieba, Tomasz; Kapelko, Małgorzata

2013-01-01

Resistant starch (RS) is part of potato starch that is not digested in the gastrointestinal tract. RS4 is a chemically modified starch (for example by oxidation and esterification) and physically (by heating). The study was aimed at determining the effect of resistant starch on lipid metabolism and activity of hepatic enzymes in Wistar strain rats fed high-fat diets containing 15% of lard or 15% of soybean oil. Four types of diets were administered to the animals (4 groups of males, n = 32): control diet (K1) containing 15% of soybean oil; control diet (K2) containing 15% of lard as well as two groups receiving the same diets with 10% addition of resistant starch RS4 (K1S and K2S). The mean concentration of total cholesterol was lower in the group of animals fed a diet with vegetable oil (39.9 mg/dl) as compared to that reported in the group of rats fed the lard-supplemented diet (55.2 mg/dl). Compared to the control groups in both groups of animals receiving the diet supplemented with resistant starch RS4 the total cholesterol concentration in serum decreased by ca. 25% (differences were statistically significant). In groups of rats receiving oil- or lard-containing diets with the addition of the resistant starch preparation the concentration of triglycerides in serum decreased by ca. 47% and 10%, respectively. A beneficial effect of the resistant starch RS4 added to Wistar rats diets on the lipid metabolism has been shown. The concentrations of total cholesterol and triglycerides in the serum were lower and concentration of HDL-cholesterol was higher in the rats fed with the diets containing the addition of the RS4 preparation as compared to the control groups. Based on the activity of hepatic enzymes the degree of liver damage was lower in groups of rats fed with diets containing resistant starch RS4 as compared to the control groups.

Polyaniline/MWCNTs/starch modified carbon paste electrode for non-enzymatic detection of cholesterol: application to real sample (cow milk).

PubMed

Gautam, Vineeta; Singh, Karan P; Yadav, Vijay L

2018-03-01

Nanocomposite materials are potentially revolutionizing many technologies, including sensors. In this paper, we described the application of "PANI/MWCNTs/Starch" modified carbon paste electrode (PCS-CPE) as a simple and highly sensitive cholesterol sensor. This novel nano-composite material has integrated nano-morphology, where polyaniline could interact effectively with the additives; pi-pi stacking "MWCNTs," and covalently bonded with starch. Specific binding sites (sugar chains), better electro-catalytic properties and fast electron transfer facilitated the oxidation of cholesterol. Fourier transform infrared spectra confirmed the interaction of cholesterol with the composite material. The sensing response of PCS was measured by cyclic voltammetry and chronoamperometry (0.1 M PBS-5 used as supporting electrolyte). As the amount of cholesterol increased in the test solution, cyclic voltammograms showed a rise of peak current (cathodic and anodic). Under the normal experimental conditions, the developed sensor exhibited wide linear dynamic range (0.032 to 5 mM) (upper limit is due to lack of solubility of cholesterol), high sensitivity (800 μAmM -1  cm -2 ), low detection limit (0.01 mM) and shorter response time (within 4-6 s). Analytical specificity, selectivity, and sensitivity during cholesterol estimation were compared with the response of some other analytes (ascorbic acid, glucose, l-dopa, urea and lactic acid). This novel sensor was successfully applied to estimate cholesterol in cow milk (used as a model real sample). The sensing platform is highly sensitive and shows a linear response towards cholesterol without using any additional redox mediator or enzyme, thus this material is extremely promising for the realization of a low-cost integrated cholesterol sensor device. Graphical abstract Cyclic voltammetric response of cholesterol of composite modified carbon paste capillary electrode.

Characterization of a starch based desiccant wheel dehumidifier

NASA Astrophysics Data System (ADS)

Beery, Kyle Edward

Starch, cellulose, and hemicellulose have an affinity for water, and adsorb water vapor from air. Materials made from combinations of these biobased sugar polymers also have been found to possess adsorptive properties. An interesting possible application of these starch-based adsorbents is the desiccant wheel dehumidifier. The desiccant wheel dehumidifier is used in conjunction with a standard air conditioning system. In this process, ambient air is passed through a stationary section while a wheel packed with desiccant rotates through that section. The desiccant adsorbs humidity (latent load) from the air, and the air conditioning system then cools the air (sensible load). Several starch based adsorbents were developed and tested for adsorptive capacity in a new high throughput screening system. The best formulations from the high throughput screening system, also taking into account economic considerations and structural integrity, were considered for use in the desiccant wheel dehumidifier. A suitable adsorbent was chosen and formulated into a matrix structure for the desiccant wheel system. A prototype desiccant wheel system was constructed and the performance was investigated under varying regeneration temperatures and rotation speeds. The results from the experiments showed that the starch based desiccant wheel dehumidification system does transfer moisture from the inlet process stream to the outlet regeneration stream. The DESSIM model was modified for the starch based adsorbent and compared to the experimental results. Also, the results when the wheel parameters were varied were compared to the predicted results from the model. The results given by the starch based desiccant wheel system show the desired proof of concept.

Atomic force microscopy of pea starch: origins of image contrast.

PubMed

Ridout, Michael J; Parker, Mary L; Hedley, Cliff L; Bogracheva, Tatiana Y; Morris, Victor J

2004-01-01

Atomic force microscopy (AFM) has been used to image the internal structure of pea starch granules. Starch granules were encased in a nonpenetrating matrix of rapid-set Araldite. Images were obtained of the internal structure of starch exposed by cutting the face of the block and of starch in sections collected on water. These images have been obtained without staining, or either chemical or enzymatic treatment of the granule. It has been demonstrated that contrast in the AFM images is due to localized absorption of water within specific regions of the exposed fragments of the starch granules. These regions swell, becoming "softer" and higher than surrounding regions. The images obtained confirm the "blocklet model" of starch granule architecture. By using topographic, error signal and force modulation imaging modes on samples of the wild-type pea starch and the high amylose r near-isogenic mutant, it has been possible to demonstrate differing structures within granules of different origin. These architectural changes provide a basis for explaining the changed appearance and functionality of the r mutant. The growth-ring structure of the granule is suggested to arise from localized "defects" in blocklet distribution within the granule. It is proposed that these defects are partially crystalline regions devoid of amylose.

High-resolution time-of-flight mass spectrometry fingerprinting of metabolites from cecum and distal colon contents of rats fed resistant starch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Timothy J.; Jones, Roger W.; Ai, Yongfeng

Time-of-flight mass spectrometry along with statistical analysis was utilized to study metabolic profiles among rats fed resistant starch (RS) diets. Fischer 344 rats were fed four starch diets consisting of 55 % (w/w, dbs) starch. A control starch diet consisting of corn starch was compared against three RS diets. The RS diets were high-amylose corn starch (HA7), HA7 chemically modified with octenyl succinic anhydride, and stearic-acid-complexed HA7 starch. A subgroup received antibiotic treatment to determine if perturbations in the gut microbiome were long lasting. A second subgroup was treated with azoxymethane (AOM), a carcinogen. At the end of the 8-weekmore » study, cecal and distal colon content samples were collected from the sacrificed rats. Metabolites were extracted from cecal and distal colon samples into acetonitrile. The extracts were then analyzed on an accurate-mass time-of-flight mass spectrometer to obtain their metabolic profile. The data were analyzed using partial least-squares discriminant analysis (PLS-DA). The PLS-DA analysis utilized a training set and verification set to classify samples within diet and treatment groups. PLS-DA could reliably differentiate the diet treatments for both cecal and distal colon samples. The PLS-DA analyses of the antibiotic and no antibiotic-treated subgroups were well classified for cecal samples and modestly separated for distal colon samples. PLS-DA analysis had limited success separating distal colon samples for rats given AOM from those not treated; the cecal samples from AOM had very poor classification. Mass spectrometry profiling coupled with PLS-DA can readily classify metabolite differences among rats given RS diets.« less

Characterisation of corn starch-based films reinforced with taro starch nanoparticles.

PubMed

Dai, Lei; Qiu, Chao; Xiong, Liu; Sun, Qingjie

2015-05-01

Taro starch nanoparticles (TSNPs) obtained by hydrolysis with pullulanase and the recrystallisation of gelatinised starch were used as reinforcing agents in corn starch films. The influence of TSNPs contents (0.5-15%) on the physical, mechanical, thermal, and structural properties of starch films was investigated. An increase in the concentration of TSNPs led to a significant decrease in the water vapour permeability (WVP) of films. The addition of TSNPs increased the tensile strength (TS) of films from 1.11 MPa to 2.87 MPa. Compared with pure starch films, the surfaces of nanocomposite films became uneven. The onset temperature (To) and melting temperature (Tm) of films containing TSNPs were higher than those of pure starch films. The addition of TSNPs improved the thermal stability of starch films. Copyright © 2014 Elsevier Ltd. All rights reserved.

Granulocytapheresis with modified fluid gelatin versus high-molecular-weight hydroxyethyl starch: a matched-pair analysis.

PubMed

Dullinger, Katharina; Pamler, Irene; Brosig, Andreas; Mohrez, Morad; Hähnel, Viola; Offner, Robert; Dormann, Frauke; Becke, Christine; Holler, Ernst; Ahrens, Norbert

2017-02-01

Granulocyte apheresis requires a sedimentation agent. Usually, hydroxyethyl starch (HES) is administered to donors for this purpose and, as granulocyte concentrate (GC) ingredient, also to patients. Authorities recently recommended suspending market authorizations for starch-containing products due to side effects. Therefore, we tested the efficacy of modified fluid gelatin (MFG, Gelafundin 4%) versus hetastarch (Hespan) for GC apheresis. This retrospective matched-pair analysis compared MFG- and hetastarch-derived GCs. Each group consisted of 15 unrelated male donors mobilized with dexamethasone and granulocyte-colony-stimulating factor for apheresis on 1 or 2 days with the COBE Spectra's PMN program. In each group, 24 GCs were collected from 15 male donors and analyzed. None of the HES-derived products, but two of the MFG-derived products (8.3%), had aggregates and could not be used. The HES-derived products had significantly higher neutrophil counts on the first day (7.7 × 10 10 /unit vs. 4.0 × 10 10 /unit; p = 0.00005) as well as second day of apheresis (4.0 × 10 10 /unit vs. 1.1 × 10 10 /unit; p = 0.0002). Median white blood cell collection efficacies were lower with MFG than with HES on Day 1 (24% vs. 43%) and Day 2 (15% vs. 37%). Twenty-one percent of the MFG-derived products had less than 1 × 10 10 granulocytes. These results indicate that granulocyte apheresis is feasible with MFG as well as with hetastarch and that the latter is superior for GC production, if used in the same dosage. In addition, aggregates in GC from the COBE Spectra were observed in the MFG group but not in the hetastarch group. © 2016 AABB.

Chemical and Biological Tools for the Preparation of Modified Histone Proteins

PubMed Central

Howard, Cecil J.; Yu, Ruixuan R.; Gardner, Miranda L.; Shimko, John C.; Ottesen, Jennifer J.

2016-01-01

Eukaryotic chromatin is a complex and dynamic system in which the DNA double helix is organized and protected by interactions with histone proteins. This system is regulated through, a large network of dynamic post-translational modifications (PTMs) exists to ensure proper gene transcription, DNA repair, and other processes involving DNA. Homogenous protein samples with precisely characterized modification sites are necessary to better understand the functions of modified histone proteins. Here, we discuss sets of chemical and biological tools that have been developed for the preparation of modified histones, with a focus on the appropriate choice of tool for a given target. We start with genetic approaches for the creation of modified histones, including the incorporation of genetic mimics of histone modifications, chemical installation of modification analogs, and the use of the expanded genetic code to incorporate modified amino acids. Additionally, we will cover the chemical ligation techniques that have been invaluable in the generation of complex modified histones that are indistinguishable from the natural counterparts. Finally, we will end with a prospectus on future directions of synthetic chromatin in living systems. PMID:25863817

Modification of flow and compressibility of corn starch using quasi-emulsion solvent diffusion method.

PubMed

Akhgari, Abbas; Sadeghi, Hasti; Dabbagh, Mohammad Ali

2014-08-01

The aim of this study was to improve flowability and compressibility characteristics of starch to use as a suitable excipient in direct compression tabletting. Quasi-emulsion solvent diffusion was used as a crystal modification method. Corn starch was dissolved in hydrochloric acid at 80°C and then ethanol as a non-solvent was added with lowering temperature until the formation of a precipitate of modified starch. Flow parameters, particle size and thermal behavior of the treated powders were compared with the native starch. Finally, the 1:1 mixture of naproxen and each excipient was tabletted, and hardness and friability of different tablets were evaluated. Larger and well shaped agglomerates were formed which showed different thermal behavior. Treated starch exhibited suitable flow properties and tablets made by the treated powder had relatively high hardness. It was found that recrystallization of corn starch by quasi emulsion solvent diffusion method could improve its flowability and compressibility characteristics.

Structural changes of starch during baking and staling of rye bread.

PubMed

Mihhalevski, Anna; Heinmaa, Ivo; Traksmaa, Rainer; Pehk, Tõnis; Mere, Arvo; Paalme, Toomas

2012-08-29

Rye sourdough breads go stale more slowly than wheat breads. To understand the peculiarities of bread staling, rye sourdough bread, wheat bread, and a number of starches were studied using wide-angle X-ray diffraction, nuclear magnetic resonance ((13)C CP MAS NMR, (1)H NMR, (31)P NMR), polarized light microscopy, rheological methods, microcalorimetry, and measurement of water activity. The degree of crystallinity of starch in breads decreased with hydration and baking to 3% and increased during 11 days of storage to 21% in rye sourdough bread and to 26% in wheat bread. (13)C NMR spectra show that the chemical structures of rye and wheat amylopectin and amylose contents are very similar; differences were found in the starch phospholipid fraction characterized by (31)P NMR. The (13)C CP MAS NMR spectra demonstrate that starch in rye sourdough breads crystallize in different forms than in wheat bread. It is proposed that different proportions of water incorporation into the crystalline structure of starch during staling and changes in starch fine structure cause the different rates of staling of rye and wheat bread.

Barrier and Mechanical Properties of Starch-Clay Nanocomposite Films

USDA-ARS?s Scientific Manuscript database

The poor barrier and mechanical properties of biopolymer-based food packaging can potentially be enhanced by the use of layered silicates (nanoclay) to produce nanocomposites. In this study, starch-clay nano-composites were synthesized by a melt extrusion method. Natural (MMT) and organically modifi...

New perspectives of starch: Synthesis and in vitro assessment of novel thiolated mucoadhesive derivatives.

PubMed

Jelkmann, Max; Bonengel, Sonja; Menzel, Claudia; Markovic, Svetislav; Bernkop-Schnürch, Andreas

2018-05-11

The purpose of this study was to develop a novel thiolated starch polymer with improved mucoadhesive properties by conjugation of cysteamine to starch as a natural polymer of restricted mucoadhesive properties. Aldehyde substructures were integrated into starch via oxidative cleavage of vicinal diols by increasing amounts of sodium periodate followed by covalent attachment of cysteamine to oxidized starch via reductive amination. Thiol groups were quantified via Ellman's reaction and their impact on mucoadhesion was analyzed by rheological investigations, the rotating cylinder method and tensile studies on porcine mucosa. The total amount of immobilized thiol groups revealed a correlation between degree of oxidation and thiolation. Modified starch demonstrated an up to 1.66-fold increase in water uptake in comparison to native starch. Modification of starch resulted in greatly improved cohesive properties and improvement in mucoadhesion. Rheological investigations revealed a 2- to 4-fold rise in viscosity of mucus. Tensile studies revealed a linear correlation between degree of oxidation/thiolation and enhancement of maximum detachment force and total work adhesion. In terms of these results, thiolated starch is a new, promising, polymer in the field of mucoadhesive drug delivery systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Mid-infrared spectroscopy and chemometrics in corn starch classification

NASA Astrophysics Data System (ADS)

Dupuy, N.; Wojciechowski, C.; Ta, C. D.; Huvenne, J. P.; Legrand, P.

1997-06-01

The authentication of food is a very important issue for both the consumer and the food industry at all levels of the food chain from raw materials to finished products. Corn starch can be used in a wide variety of food preparations such as bakery cream fillings, sauces, salad dressings, frozen foods etc. Many modifications are made to corn starch in connection with its use in agrofood. The value of the product increases with the degree of modification. Some chemical and physical tests have been devised to solve the problem of identifying these modifications but all the methods are time consuming and require skilled operators. We separate corn starches into groups related to their modification on the basis of the infrared spectra.

The Simultaneous Abolition of Three Starch Hydrolases Blocks Transient Starch Breakdown in Arabidopsis*

PubMed Central

Streb, Sebastian; Eicke, Simona; Zeeman, Samuel C.

2012-01-01

In this study, we investigated which enzymes are involved in debranching amylopectin during transient starch degradation. Previous studies identified two debranching enzymes, isoamylase 3 (ISA3) and limit dextrinase (LDA), involved in this process. However, plants lacking both enzymes still degrade substantial amounts of starch. Thus, other enzymes/mechanisms must contribute to starch breakdown. We show that the chloroplastic α-amylase 3 (AMY3) also participates in starch degradation and provide evidence that all three enzymes can act directly at the starch granule surface. The isa3 mutant has a starch excess phenotype, reflecting impaired starch breakdown. In contrast, removal of AMY3, LDA, or both enzymes together has no impact on starch degradation. However, removal of AMY3 or LDA in addition to ISA3 enhances the starch excess phenotype. In plants lacking all three enzymes, starch breakdown is effectively blocked, and starch accumulates to the highest levels observed so far. This provides indirect evidence that the heteromultimeric debranching enzyme ISA1-ISA2 is not involved in starch breakdown. However, we illustrate that ISA1-ISA2 can hydrolyze small soluble branched glucans that accumulate when ISA3 and LDA are missing, albeit at a slow rate. Starch accumulation in the mutants correlates inversely with plant growth. PMID:23019330

Engineering starch accumulation by manipulation of phosphate metabolism of starch.

PubMed

Weise, Sean E; Aung, Kimberly; Jarou, Zach J; Mehrshahi, Payam; Li, Ziru; Hardy, Anna C; Carr, David J; Sharkey, Thomas D

2012-06-01

A new understanding of leaf starch degradation has emerged in the last 10 years. It has been shown that starch phosphorylation and dephosphorylation are critical components of this process. Glucan, water dikinase (GWD) (and phosphoglucan, water dikinase) adds phosphate to starch, and phosphoglucan phosphatase (SEX4) removes these phosphates. To explore the use of this metabolism to manipulate starch accumulation, Arabidopsis (Arabidopsis thaliana) plants were engineered by introducing RNAi constructs designed to reduce expression of AtGWD and AtSEX4. The timing of starch build-up was altered with ethanol-inducible and senescence-induced gene promoters. Ethanol induction of RNAi lines reduced transcript for AtGWD and AtSEX4 by 50%. The transgenic lines had seven times more starch than wild type at the end of the dark period but similar growth rates and total biomass. Elevated leaf starch content in maize leaves was engineered by making an RNAi construct against a gene in maize that appeared to be homologous to AtGWD. The RNAi construct was expressed using the constitutive ubiquitin promoter. Leaf starch content at the end of a night period in engineered maize plants was 20-fold higher than in untransformed plants with no impact on total plant biomass. We conclude that plants can be engineered to accumulate starch in the leaves with little impact on vegetative biomass. © 2012 The Authors. Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Influence of starch on microalgal biomass recovery, settleability and biogas production.

PubMed

Gutiérrez, Raquel; Ferrer, Ivet; García, Joan; Uggetti, Enrica

2015-06-01

In the context of wastewater treatment with microalgae cultures, coagulation-flocculation followed by sedimentation is one of the suitable options for microalgae harvesting. This process is enabled by the addition of chemicals (e.g. iron). However, in a biorefinery perspective, it is important to avoid possible contamination of downstream products caused by chemicals addition. The aim of this study was to evaluate the effect of potato starch as flocculant for microalgal biomass coagulation-flocculation and sedimentation. The optimal flocculant dose (25mg/L) was determined with jar tests. Such a concentration led to more than 95% biomass recovery (turbidity<9NTU). The settleability of flocs was studied using an elutriation apparatus measuring the settling velocities distribution. This test underlined the positive effect of starch on the biomass settling velocity, increasing to >70% the percentage of particles with settling velocities >6.5m/h. Finally, biochemical methane potential tests showed that starch biodegradation increased the biogas production from harvested biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nano CaCO₃ imprinted starch hybrid polyethylhexylacrylate\\polyvinylalcohol nanocomposite thin films.

PubMed

Prusty, Kalyani; Swain, Sarat K

2016-03-30

Starch hybrid polyethylhexylacrylate (PEHA)/polyvinylalcohol (PVA) nanocomposite thin films are prepared by different composition of nano CaCO3 in aqueous medium. The chemical interaction of nano CaCO3 with PEHA in presence of starch and PVA is investigated by Fourier transforms infrared spectroscopy (FTIR). X-ray diffraction (XRD) is used in order to study the change in crystallite size and d-spacing during the formation of nanocomposite thin film. The surface morphology of nanofilms is studied by scanning electron microscope (SEM). The topology and surface roughness of the films is noticed by atomic force microscope (AFM). The tensile strength, thermal stability and thermal conductivity of films are increased with increase in concentrations of CaCO3 nanopowder. The chemical resistance and biodegradable properties of the nanocomposite thin films are also investigated. The growth of bacteria and fungi in starch hybrid PEHA film is reduced substantially with imprint of nano CaCO3. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phosphoethanolamine cellulose: A naturally produced chemically modified cellulose.

PubMed

Thongsomboon, Wiriya; Serra, Diego O; Possling, Alexandra; Hadjineophytou, Chris; Hengge, Regine; Cegelski, Lynette

2018-01-19

Cellulose is a major contributor to the chemical and mechanical properties of plants and assumes structural roles in bacterial communities termed biofilms. We find that Escherichia coli produces chemically modified cellulose that is required for extracellular matrix assembly and biofilm architecture. Solid-state nuclear magnetic resonance spectroscopy of the intact and insoluble material elucidates the zwitterionic phosphoethanolamine modification that had evaded detection by conventional methods. Installation of the phosphoethanolamine group requires BcsG, a proposed phosphoethanolamine transferase, with biofilm-promoting cyclic diguanylate monophosphate input through a BcsE-BcsF-BcsG transmembrane signaling pathway. The bcsEFG operon is present in many bacteria, including Salmonella species, that also produce the modified cellulose. The discovery of phosphoethanolamine cellulose and the genetic and molecular basis for its production offers opportunities to modulate its production in bacteria and inspires efforts to biosynthetically engineer alternatively modified cellulosic materials. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Starch blockers--their effect on calorie absorption from a high-starch meal.

PubMed

Bo-Linn, G W; Santa Ana, C A; Morawski, S G; Fordtran, J S

1982-12-02

It has been known for more than 25 years that certain plant foods, such as kidney beans and wheat, contain a substance that inhibits the activity of salivary and pancreatic amylase. More recently, this antiamylase has been purified and marketed for use in weight control under the generic name "starch blockers." Although this approach to weight control is highly popular, it has never been shown whether starch-blocker tablets actually reduce the absorption of calories from starch. Using a one-day calorie-balance technique and a high-starch (100 g) meal (spaghetti, tomato sauce, and bread), we measured the excretion of fecal calories after normal subjects had taken either placebo or starch-blocker tablets. If the starch-blocker tablets had prevented the digestion of starch, fecal calorie excretion should have increased by 400 kcal. However, fecal calorie excretion was the same on the two test days (mean +/- S.E.M., 80 +/- 4 as compared with 78 +/- 2). We conclude that starch-blocker tablets do not inhibit the digestion and absorption of starch calories in human beings.

EFFECT OF SIMULTANEOUSLY SILICIFIED MICROCRYSTALLINE CELLULOSE AND PREGELATINIZED STARCH ON THE THEOPHYLLINE TABLETS STABILITY.

PubMed

Mazurek-Wadołkowska, Edyta; Winnicka, Katarzyna; Czyzewska, Urszula; Miltyk, Wojciech

2016-07-01

High profitability and simplicity of direct compression, encourages pharmaceutical industry to create universal excipients to improve technology process. Prosolv® SMCC - silicified microcrystalline cellulose and Starch 1500® - pregelatinized starch, are the example of multifunctional excipients. The aim of the present study was to evaluate the stability of theophylline (API) in the mixtures with excipients with various physico-chemical properties (Prosolv® SMCC 90, Prosolv® SMCC HD 90, Prosolv* SMCC 50®, Starch 1500® and magnesium stearate). The study presents results of thermal analysis of the mixtures with theophylline before and after 6 months storage of the tablets at various temperatures and relative humidity conditions (25 ± 2°C/40 ± 5% RH, 40 ± 2°C/75 ± 5% RH). It was shown that high concentration of Starch 1500® (49%) affects the stability of the theophylline tablets with Prosolv® SMCC. Prosolv® SMCC had no effect on API stability as confirmed by the differential scanning calorimetry (DSC). Changes in peak placements were observed just after tabletting process, which might indicate that compression accelerated the incompatibilities between theophylline and Starch 1500. TGA analysis showed loss in tablets mass equal to water content in starch. GC-MS study established no chemical decomposition of theophylline. We demonstrated that high content of Starch 1500® (49%) in the tablet mass, affects stability on tablets containing theophylline and Prosolv® SMCC.

Cooking behavior and starch digestibility of NUTRIOSE® (resistant starch) enriched noodles from sweet potato flour and starch.

PubMed

Menon, Renjusha; Padmaja, G; Sajeev, M S

2015-09-01

The effect of a resistant starch source, NUTRIOSE® FB06 at 10%, 15% and 20% in sweet potato flour (SPF) and 5% and 10% in sweet potato starch (SPS) in reducing the starch digestibility and glycaemic index of noodles was investigated. While NUTRIOSE (10%) significantly reduced the cooking loss in SPF noodles, this was enhanced in SPS noodles and guar gum (GG) supplementation reduced CL of both noodles. In vitro starch digestibility (IVSD) was significantly reduced in test noodles compared to 73.6g glucose/100g starch in control SPF and 65.9 g in SPS noodles. Resistant starch (RS) was 54.96% for NUTRIOSE (15%)+GG (1%) fortified SPF noodles and 53.3% for NUTRIOSE (5%)+GG (0.5%) fortified SPS noodles, as against 33.8% and 40.68%, respectively in SPF and SPS controls. Lowest glycaemic index (54.58) and the highest sensory scores (4.23) were obtained for noodles with 15% NUTRIOSE+1% GG. Copyright © 2015 Elsevier Ltd. All rights reserved.

Correlation between dynamic wetting behavior and chemical components of thermally modified wood

NASA Astrophysics Data System (ADS)

Wang, Wang; Zhu, Yuan; Cao, Jinzhen; Sun, Wenjing

2015-01-01

In order to investigate the dynamic wetting behavior of thermally modified wood, Cathay poplar (Populus cathayana Rehd.) and Scots pine (Pinus sylvestris L.) samples were thermally modified in an oven at 160, 180, 200, 220 or 240 °C for 4 h in this study. The dynamic contact angles and droplet volumes of water droplets on modified and unmodified wood surfaces were measured by sessile drop method, and their changing rates (expression index: K value and wetting slope) calculated by wetting models were illustrated for mapping the dynamic wetting process. The surface chemical components were also measured by X-ray photoelectron spectroscopy analysis (XPS), thus the relationship between dynamic wetting behavior and chemical components of thermally modified wood were determined. The results indicated that thermal modification was capable of decreasing the dynamic wettability of wood, expressed in lowing spread and penetration speed of water droplets on wood surfaces. This change was more obvious with the increased heating temperature. The K values varied linearly with the chemical components parameter (mass loss, O/C ratio, and C1/C2 ratio), indicating a strong correlation between dynamic wetting behavior and chemical components of thermally modified wood.

Preparation and physicochemistry properties of smart edible films based on gelatin-starch nanoparticles.

PubMed

Tao, Furong; Shi, Chengmei; Cui, Yuezhi

2018-04-24

Among the natural polymers able to form edible films, starch and gelatin (Gel) are potential sources. Corn starch is a polysaccharide widely produced around the world, and gelatin differs from other hydrocolloids as a fully digestible protein, containing nearly all the essential amino acids, except tryptophan. Based on this, with advantages such as abundance, relatively low cost, biodegradability, and edibility, studies considering alternative systems for food protection that utilize biopolymers have increased significantly in the recent years. A novel macromolecular crosslinker Starch-BTCAD-NHS (starch - butanetetracarboxylic acid dianhydride - N-hydroxysuccinimide, SBN) was successfully prepared to modify gelatin film. Compared with the blank gelatin films, the resulting SBN-Gel films exhibited the improved surface hydrophobicity, the higher tense strength and elongation-at-break, the lower Young's modulus values, the greater opacity, the poorer water vapor uptake properties and better anti-degradation capacity. The modified gelatin film material with advanced properties obtained in this work was safe, stable eco-friendly and biorefractory, and was an ideal choice to form a packaging in food industry. Also, the crosslinking SBN-gelatin coating was effective in reducing the corruption and extending the shelf life for the peeled apple substantially. This article is protected by copyright. All rights reserved.

New starch methodology to measure both soluble and insoluble starch

USDA-ARS?s Scientific Manuscript database

Starch is a natural sugarcane juice impurity that greatly influences raw sugar quality and affects factory and refinery processing. Since the advent of the USDA Starch Research method, the mechanisms in which starch concentration and physical form affects sugar crop processing, conversion, and end-g...

Effect of heat-moisture treatment on multi-scale structures and physicochemical properties of breadfruit starch.

PubMed

Tan, Xiaoyan; Li, Xiaoxi; Chen, Ling; Xie, Fengwei; Li, Lin; Huang, Jidong

2017-04-01

Breadfruit starch was subjected to heat-moisture treatment (HMT) at different moisture content (MC). HMT did not apparently change the starch granule morphology but decreased the molecular weight and increased the amylose content. With increased MC, HMT transformed the crystalline structure (B→A+B→A) and decreased the relative crystallinity. With ≥25% MC, the scattering peak at ca. 0.6nm -1 disappeared, suggesting the lamellar structure was damaged. Compared with native starch, HMT-modified samples showed greater thermostability. Increased MC contributed to a higher pasting temperature, lower viscosity, and no breakdown. The pasting temperature of native and HMT samples ranged from 68.8 to 86.2°C. HMT increased the slowly-digestible starch (SDS) and resistant starch (RS) contents. The SDS content was 13.24% with 35% MC, which was 10.25% higher than that of native starch. The increased enzyme resistance could be ascribed to the rearrangement of molecular chains and more compact granule structure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Encoded libraries of chemically modified peptides.

PubMed

Heinis, Christian; Winter, Greg

2015-06-01

The use of powerful technologies for generating and screening DNA-encoded protein libraries has helped drive the development of proteins as pharmaceutical ligands. However the development of peptides as pharmaceutical ligands has been more limited. Although encoded peptide libraries are typically several orders of magnitude larger than classical chemical libraries, can be more readily screened, and can give rise to higher affinity ligands, their use as pharmaceutical ligands is limited by their intrinsic properties. Two of the intrinsic limitations include the rotational flexibility of the peptide backbone and the limited number (20) of natural amino acids. However these limitations can be overcome by use of chemical modification. For example, the libraries can be modified to introduce topological constraints such as cyclization linkers, or to introduce new chemical entities such as small molecule ligands, fluorophores and photo-switchable compounds. This article reviews the chemistry involved, the properties of the peptide ligands, and the new opportunities offered by chemical modification of DNA-encoded peptide libraries. Copyright © 2015. Published by Elsevier Ltd.

Physicochemical properties of kiwifruit starch.

PubMed

Li, Dongxing; Zhu, Fan

2017-04-01

Three varieties of golden kiwifruit (Actinidia chinensis) (Gold3, Gold9 and Hort16A) were collected at the commercial harvesting time, and physicochemical properties of starches from core and outer pericarp were studied. Starch contents (dry weight basis) in outer pericarp and core tissues ranged from 38.6 to 51.8% and 34.6 to 40.7%, respectively. All the kiwifruit starches showed B-type polymorph. Compared to the outer pericarp starches, amylose content and enzyme susceptibility of core starches were higher, and the degree of crystallinity, granule size and gelatinization parameters of core starches were somewhat lower. This suggests different biosynthetic properties between these two starches. The enthalpy changes of gelatinization of outer pericarp starches were high (∼21J/g). Rheological properties of outer pericarp starches were compared with normal maize and potato starches showed high yield stress of flow properties. This study revealed the unique properties of kiwifruit starch among various types of starches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of Agitation in Alkalization Process on the Characteristics of Sodium Carboxymethyl Sago and Cassava Starches

NASA Astrophysics Data System (ADS)

Titi, C. S.; Fachrudin, R.; Ruriani, E.; Yuliasih, I.

2018-05-01

Sodium carboxymethyl starch (Sodium CMS) is a modified starch prepared by two successive processes, alkalization and etherification. Alkalization will change the activated hydroxyl group of starch to more reactive alkoxide (St-O-), and then carboxymethyl group will substitute the hydroxyl group into sodium CMS. This research investigated the effect of agitation (1000 rpm of stirring and 4000 rpm of homogenization) in alkalization process to the modification of native starch into sodium CMS. Cassava and sago starches were mixed with sodium hydroxide (1.8 and 1.9 moles per mole anhydrous glucose units). The combination of NaOH and homogenizing gave the highest degrees of substitution for cassava (DS 0.73) and sago (DS 0.55) starches. The sodium CMS characteristics (paste clarity, water and oil absorption capacities, solubility, swelling power) were a function of mixing method but not on the amount of NaOH used.

Effect of conditions of modification on thermal and rheological properties of phosphorylated pumpkin starch.

PubMed

Przetaczek-Rożnowska, Izabela; Fortuna, Teresa

2017-11-01

This study aimed at analyzing the effect of conditions of modification process on thermal and rheological properties of phosphorylated pumpkin starch. The esterification process was conducted at 115°C and 145°C for 1, 2, and 3h. The thermodynamic properties of samples were determined using differential scanning calorimetry (DSC), flow curves were plotted and the resulting curves were described the Herschel-Bulkley model, textural properties were evaluated with the TPA method. The data proved that the chemical modification of starch affected its rheological and thermal characteristics, but the direction and extent of the changes were found to depend on both temperature and duration of phoshorylation. The results demonstrated that temperatures of gelatinization of the samples modified at 145°C were higher by 1.4-8.5°C than those of the samples obtained at 115°C. Prolongation of starch modification at 115°C caused reduction of shear stress (from 2.10Pa to 0.86Pa), and higher temperature of esterification also reduced the value of this parameter. The hardness of the samples heated at 145°C was higher by 45-59N than that of heated at 115°C. Adjustment of phosphorylation process caused an increase in gumminess by 1.8-37.9N, wherein higher temperature and process prolongation resulted in the highest gumminess. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of the Significance of Starch Surface Binding Sites on Human Pancreatic α-Amylase.

PubMed

Zhang, Xiaohua; Caner, Sami; Kwan, Emily; Li, Chunmin; Brayer, Gary D; Withers, Stephen G

2016-11-01

Starch provides the major source of caloric intake in many diets. Cleavage of starch into malto-oligosaccharides in the gut is catalyzed by pancreatic α-amylase. These oligosaccharides are then further cleaved by gut wall α-glucosidases to release glucose, which is absorbed into the bloodstream. Potential surface binding sites for starch on the pancreatic amylase, distinct from the active site of the amylase, have been identified through X-ray crystallographic analyses. The role of these sites in the degradation of both starch granules and soluble starch was probed by the generation of a series of surface variants modified at each site to disrupt binding. Kinetic analysis of the binding and/or cleavage of substrates ranging from simple maltotriosides to soluble starch and insoluble starch granules has allowed evaluation of the potential role of each such surface site. In this way, two key surface binding sites, on the same face as the active site, are identified. One site, containing a pair of aromatic residues, is responsible for attachment to starch granules, while a second site featuring a tryptophan residue around which a malto-oligosaccharide wraps is shown to heavily influence soluble starch binding and hydrolysis. These studies provide insights into the mechanisms by which enzymes tackle the degradation of largely insoluble polymers and also present some new approaches to the interrogation of the binding sites involved.

40 CFR 372.20 - Process for modifying covered chemicals and facilities.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chemicals and facilities. 372.20 Section 372.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS TOXIC CHEMICAL RELEASE REPORTING: COMMUNITY RIGHT-TO-KNOW Reporting Requirements § 372.20 Process for modifying covered chemicals...

Starch and protein chemistry and functional properties

USDA-ARS?s Scientific Manuscript database

Starch and protein are the major constituents of all cereal grains and are an important source of nutrition for humans and animals. Worldwide, sorghum and the millets are basic food staples for millions of people and are important sources of animal feed, and in some cases fuel. The chemical properti...

Study on Esterification Reaction of Starch Isolated from Cassava (Manihot esculeta) with Acetic Acid and Isopropyl Myrtistate Using Ultrasonicator

NASA Astrophysics Data System (ADS)

Wika Amini, Helda; Masruri; Mariyah Ulfa, Siti

2018-01-01

Cassava starch is a polysaccharide consists of amylose and amylopectin. This research was purposed to modify the starch isolated from local cassava (Manihot esculenta). Modification was undertaken to study the esterification reaction of cassava starch with acetic acid and with isopropyl myristate. Moreover, morphology observation was also conducted both for original starch and its modification yields. It was found that cassava’s starch was isolated in 16.4% yield as a white powder. Esterification on the starch provided DS value 0.549 for ratio 1:2 of starch-acetic acid. It gave DS value 0.356 for ratio 1:3 of starch-isopropyl myristate. Treatment by ultrasonication from 0 to 60 minutes was significantly improved the DS value to 0.549 for starch-acetic acid. But it gave DS value to 0.413 for 30 minute ultrasonication of starch-isopropyl myristate. In addition, morphology of the starch observed by microscope gave different features with starch ester acetate and starch ester myristate. The original starch consists of granules, but starch ester acetate indicates a non-granules shape (amorf solid). Moreover for starch ester myristate shows a rather bigger size of granules, and all of the granules afforded were round and oval.

Preparation and characterization of non-crystalline granular starch and corresponding carboxymethyl starch.

PubMed

Zhang, Bao; Li, Xiaomin; Xie, Qiutao; Tao, Han; Wang, Wu; Chen, Han-Qing

2017-10-01

Native corn starch slurried in 50% ethanol solution was treated at 60°C, 70°C, 80°C, and 85°C, respectively. The resultant starches were investigated by polarized microscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffractometry (XRD). The Maltese cross of ethanol-heating treated starch gradually weaken with increasing temperature and completely disappeared at 85°C. SEM data indicated the treated granular exhibited a rougher surface with more pores and grooves than native starch granular, but the shape of the treated starch was still intact. DSC and XRD data confirmed ethanol-heating treated starch changed from crystalline to non-crystalline structure at 85°C. The highest degree of substitution (DS) and corresponding reaction efficiency (RE) for the carboxymethylation of native starch were 0.66 and 36.7%, respectively, while the corresponding DS and RE for non-crystalline granular starches increased by 0.29 and 16.1% at the same reaction condition, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

Biological resistance of polyethylene composites made with chemically modified fiber or flour

Treesearch

Rebecca E. Ibach; Craig M. Clemons

2002-01-01

The role of moisture in the biological decay of wood-plastic composites was investigated. Southern pine wood fiber and ponderosa pine wood flour were chemically modified using either acetic anhydride (AA), butylene oxide (BO), or propylene oxide (PO). A 50:50 mixture of high density polyethylene and either chemically modified fiber or flour, or untreated fiber or flour...

Engineering Escherichia coli K12 MG1655 to use starch

PubMed Central

2014-01-01

Background To attain a sustainable bioeconomy, fuel, or valuable product, production must use biomass as substrate. Starch is one of the most abundant biomass resources and is present as waste or as a food and agroindustry by-product. Unfortunately, Escherichia coli, one of the most widely used microorganisms in biotechnological processes, cannot use starch as a carbon source. Results We engineered an E. coli strain capable of using starch as a substrate. The genetic design employed the native capability of the bacterium to use maltodextrins as a carbon source plus expression and secretion of its endogenous α-amylase, AmyA, in an adapted background. Biomass production improved using 35% dissolved oxygen and pH 7.2 in a controlled bioreactor. Conclusion The engineered E. coli strain can use starch from the milieu and open the possibility of optimize the process to use agroindustrial wastes to produce biofuels and other valuable chemicals. PMID:24886307

Effect of high hydrostatic pressure and retrogradation treatments on structural and physicochemical properties of waxy wheat starch.

PubMed

Hu, Xiao-Pei; Zhang, Bao; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

2017-10-01

In this study, the effects of high hydrostatic pressure and retrogradation (HHPR) treatments on in vitro digestibility, structural and physicochemical properties of waxy wheat starch were investigated. The waxy wheat starch slurries (10%, w/v) were treated with high hydrostatic pressures of 300, 400, 500, 600MPa at 20°C for 30min, respectively, and then retrograded at 4°C for 4d. The results indicated that the content of slowly digestible starch (SDS) in HHPR-treated starch samples increased with increasing pressure level, and it reached the maximum (31.12%) at 600MPa. HHPR treatment decreased the gelatinization temperatures, the gelatinization enthalpy, the relative crystallinity and the peak viscosity of the starch samples. Moreover, HHPR treatment destroyed the surface and interior structures of starch granules. These results suggest that the in vitro digestibility, physicochemical, and structural properties of waxy wheat starch are effectively modified by HHPR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physicochemical properties and in vitro digestibility of sorghum starch altered by high hydrostatic pressure.

PubMed

Liu, Hang; Fan, Huanhuan; Cao, Rong; Blanchard, Christopher; Wang, Min

2016-11-01

A nonthermal processing technology, high hydrostatic pressure (HHP) treatment, was investigated to assess its influence on the physicochemical properties and in vitro digestibility of sorghum starch (SS). There was no change in the 'A'-type crystalline pattern of SS after the pressure treatments at 120-480MPa. However, treatment at 600MPa produced a pattern similar to 'B'-type crystalline. HHP treatment also resulted in SS granules with rough surfaces. Measured amylose content, water absorption capacity, alkaline water retention, pasting temperature and thermostability increased with increasing pressure levels, while the oil absorption capacity, swelling power, relative crystallinity and viscosity decreased. Compared with native starch, HHP-modified SS samples had lower in vitro hydrolysis, reduced amount of rapidly digestible starch, as well as increased levels of slowly digestible starch and resistant starch. These results indicate that HHP treatment is an effective modification method for altering in vitro digestibility and physicochemical properties of SS. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of acetic acid on physical properties of pregelatinized wheat and corn starch gels.

PubMed

Majzoobi, Mahsa; Kaveh, Zahra; Farahnaky, Asgar

2016-04-01

Pregelatinized starches are physically modified starches with ability to absorb water and increase viscosity at ambient temperature. The main purpose of this study was to determine how different concentrations of acetic acid (0, 500, 1000, 10,000 mg/kg) can affect functional properties of pregelatinized wheat and corn starches (PGWS and PGCS, respectively) produced by a twin drum drier. With increasing acetic acid following changes occurred for both samples; cold water solubility (at 25 °C) increased, water absorption and apparent cold water viscosity (at 25 °C) reduced, the smooth surface of the starch particles converted to an uneven surface as confirmed by scanning electron microscopy, cohesiveness, consistency and turbidity of the starch gels reduced while their syneresis increased. It was found that in presence of acetic acid, PGWS resulted in higher water absorption and apparent cold water viscosity and produced more cohesive and turbid gels with less syneresis compared to PGCS. Copyright © 2015 Elsevier Ltd. All rights reserved.

Magnetorheological finishing of chemical-vapor deposited zinc sulfide via chemically and mechanically modified fluids.

PubMed

Salzman, Sivan; Romanofsky, Henry J; Giannechini, Lucca J; Jacobs, Stephen D; Lambropoulos, John C

2016-02-20

We describe the anisotropy in the material removal rate (MRR) of the polycrystalline, chemical-vapor deposited zinc sulfide (ZnS). We define the polycrystalline anisotropy via microhardness and chemical erosion tests for four crystallographic orientations of ZnS: (100), (110), (111), and (311). Anisotropy in the MRR was studied under magnetorheological finishing (MRF) conditions. Three chemically and mechanically modified magnetorheological (MR) fluids at pH values of 4, 5, and 6 were used to test the MRR variations among the four single-crystal planes. When polishing the single-crystal planes and the polycrystalline with pH 5 and pH 6 MR fluids, variations were found in the MRR among the four single-crystal planes and surface artifacts were observed on the polycrystalline material. When polishing the single-crystal planes and the polycrystalline with the modified MR fluid at pH 4, however, minimal variation was observed in the MRR among the four orientations and a reduction in surface artifacts was achieved on the polycrystalline material.

The effect on biological and moisture resistance of epichlorohydrin chemically modified wood

Treesearch

Rebecca E. Ibach; Beom-Goo Lee

2002-01-01

Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached for 2 weeks...

Effects of corn fiber gum with different molecular weights on the gelatinization behaviors of corn and wheat starch

USDA-ARS?s Scientific Manuscript database

Corn fiber gum (CFG) is a novel arabinoxylan hydrocolloid. Recent research has shown that it has a considerable potential in food processing. In our previous study, we reported that CFG could be used to modify the gelling and rheological properties of starch-based food. In this study, starch and CFG...

Physicochemical properties and starch digestibility of whole grain sorghums, millet, quinoa and amaranth flours, as affected by starch and non-starch constituents.

PubMed

Srichuwong, Sathaporn; Curti, Delphine; Austin, Sean; King, Roberto; Lamothe, Lisa; Gloria-Hernandez, Hugo

2017-10-15

Minor grains such as sorghum, millet, quinoa and amaranth can be alternatives to wheat and corn as ingredients for whole grain and gluten-free products. In this study, influences of starch structures and other grain constituents on physicochemical properties and starch digestibility of whole flours made from these grains were investigated. Starches were classified into two groups according to their amylopectin branch chain-length: (i) quinoa, amaranth, wheat (shorter chains); and (ii) sorghum, millet, corn (longer chains). Such amylopectin features and amylose content contributed to the differences in thermal and pasting properties as well as starch digestibility of the flours. Non-starch constituents had additional impacts; proteins delayed starch gelatinization and pasting, especially in sorghum flours, and high levels of soluble fibre retarded starch retrogradation in wheat, quinoa and amaranth flours. Enzymatic hydrolysis of starch was restricted by the presence of associated protein matrix and enzyme inhibitors, but accelerated by endogenous amylolytic enzymes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of starch structure on glucose and insulin responses in adults.

PubMed

Behall, K M; Scholfield, D J; Canary, J

1988-03-01

Twelve women and 13 men were given meals containing cornstarch with 70% of the starch in the form of amylopectin or amylose to determine if differences in glycemic response result from different chemical structure. Blood was drawn before and 30, 60, 120, and 180 min after each meal. The meals consisted of starch crackers fed at the rate of 1 g carbohydrate from starch per kilogram body weight. The amylose meal resulted in a significantly lower glucose peak at 30 min than did the amylopectin meal. Plasma insulin response was significantly lower 30 and 60 min after amylose than after the amylopectin meal. Summed insulin above fasting was significantly lower after amylose while summed glucose was not significantly different between the two meals. The sustained plasma glucose levels after the amylose meal with reduced insulin requirement suggest amylose starch may be of potential benefit to carbohydrate-sensitive or diabetic individuals.

Morphology, crystallinity, pasting, thermal and quality characteristics of starches from adzuki bean (Vigna angularis L.) and edible kudzu (Pueraria thomsonii Benth).

PubMed

Reddy, Chagam Koteswara; Luan, Fei; Xu, Baojun

2017-12-01

Starches were isolated from adzuki bean (Vigna angularis L.) and edible kudzu (Pueraria thomsonii Benth) and investigated for their physico-chemical, morphological, pasting, crystallinity, thermal and FT-IR spectroscopic characteristics. Statistical analysis of physico-chemical and functional characteristics showed significant (p<0.05) difference between isolated starches from adzuki bean and edible kudzu. The XRD pattern of starches from adzuki bean and edible kudzu showed A-type with reflections (2θ) at 15.0°, 17.03°, 17.89°, 23.18°and 15.12°, 17.03°, 17.77°, 23.3°, respectively. The starch granules from adzuki bean were smooth, round, oval to kidney or irregular while those of edible kudzu starch were spherical, hemispherical and polygonal. Edible kudzu starch exhibited high pasting temperature, gelatinization temperatures, enthalpy and less pasting parameters as compared to starch from adzuki bean. Peaks in FT-IR spectra of both starches shown its carbohydrate nature. Starch from adzuki bean showed high swelling power and solubility as compared to edible kudzu, and enhanced the swelling power and solubility of isolated starches with the temperature raised from 50°C and 90°C. Finally, this work offers data for the application of starches isolated from adzuki bean and edible kudzu that would be applicable for both food and non-food industries. Copyright © 2017 Elsevier B.V. All rights reserved.

Starch-Branching Enzymes Preferentially Associated with A-Type Starch Granules in Wheat Endosperm1

PubMed Central

Peng, Mingsheng; Gao, Ming; Båga, Monica; Hucl, Pierre; Chibbar, Ravindra N.

2000-01-01

Two starch granule-bound proteins (SGP), SGP-140 and SGP-145, were preferentially associated with A-type starch granules (>10 μm) in developing and mature wheat (Triticum aestivum) kernels. Immunoblotting and N-terminal sequencing suggested that the two proteins were different variants of SBEIc, a 152-kD isoform of wheat starch-branching enzyme. Both SGP-140 and SGP-145 were localized to the endosperm starch granules but were not found in the endosperm soluble fraction or pericarp starch granules younger than 15 d post anthesis (DPA). Small-size starch granules (<10 μm) initiated before 15 DPA incorporated SGP-140 and SGP-145 throughout endosperm development and grew into full-size A-type starch granules (>10 μm). In contrast, small-size starch granules harvested after 15 DPA contained only low amounts of SGP-140 and SGP-145 and developed mainly into B-type starch granules (<10 μm). Polypeptides of similar mass and immunologically related to SGP-140 and/or SGP-145 were also preferentially incorporated into A-type starch granules of barley (Hordeum vulgare), rye (Secale cereale), and triticale (× Triticosecale Wittmack) endosperm, which like wheat endosperm have a bimodal starch granule size distribution. PMID:10982441

Investigation on the pitting of potato starch granules during high frequency ultrasound treatment.

PubMed

Bai, Wenzhe; Hébraud, Pascal; Ashokkumar, Muthupandian; Hemar, Yacine

2017-03-01

In this paper, the pitting of potato starch granules in aqueous suspensions (1%) by high-frequency high-power ultrasound (850kHz at a power of 0.2W, 2W or 3.7W; and also 500kHz and 1MHz at a power of 2W) is reported. The number of pits per starch granules was found to be independent of the amylose content of starches, and the surface properties of starch granules as modified through SDS and ethanol washing. At 850kHz, the maximum number of pits per starch granule, for both normal and waxy starches, did not exceed 11. However, a close inspection of fractionated starch granules based on their sizes showed that there is an optimum granule size for which a maximum pit number is obtained. For example, starch granules with diameter size range of ∼15 to ∼30μm had a maximum pit number (between 10 and 20 pits per granule) when sonicated (2W, 850kHz and 30min); while sonication of small (<10μm) and very large (>45μm) granules resulted in a smaller number of pits per granule (∼5). Further, the maximum number of pits per granules is also found to be proportional to the ultrasound frequency, with values of approximately 7, 10 and 11 at 0.50, 0.85, and 1MHz, respectively. FTIR measurements did not show any breakup of starch molecules. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of roasted pea flour/starch and encapsulated pea starch incorporation on the in vitro starch digestibility of pea breads.

PubMed

Lu, Zhan-Hui; Donner, Elizabeth; Liu, Qiang

2018-04-15

Oven or microwave roasting and alginate encapsulation of pea flour and starch to produce novel pea ingredients for enrichment of slowly digestible starch (SDS) and resistant starch (RS) content in pea bread were investigated. Pea flour treated either by oven roasting (160°C, 30min) or by microwave roasting (1.1kW, 6min) effectively retained its low starch digestibility similar to its native form (∼25% SDS; ∼60% RS). When oven roasting was applied to pea starch, SDS content increased triply compared to the fully boiled counterpart. Alginate encapsulation effectively controlled carbohydrate release to simulated gastric, intestinal and colonic fluids, and thus largely enriched the SDS and RS fractions in starch. Pea bread containing up to 37.5% of encapsulated roasted MPS pea starch not only provided high SDS and RS fractions (23.9% SDS and 30.2% RS) compared to a white bread control (0.2% SDS and 2.5% RS), but also provided an acceptable palatability. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Water barrier properties of starch films reinforced with cellulose nanocrystals obtained from sugarcane bagasse.

PubMed

Slavutsky, Aníbal M; Bertuzzi, María A

2014-09-22

Water transport in edible films based on hydrophilic materials such as starch, is a complex phenomenon due to the strong interaction of sorbed water molecules with the polymeric structure. Cellulose nanocrystals (CNC) were obtained from sugarcane bagasse. Starch and starch/CNC films were formulated and their water barrier properties were studied. The measured film solubility, contact angle, and water sorption isotherm indicated that reinforced starch/CNC films have a lower affinity to water molecules than starch films. The effects that the driving force and the water activity (aw) values at each side of the film have on permeability were analyzed. Permeability, diffusivity, and solubility coefficients indicated that the permeation process depends mostly on the tortuous pathway formed by the incorporation of CNC and therefore were mainly controlled by water diffusion. The interaction between CNC and starch chain is favoured by the chemical similarities of both molecules. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polyethylene Glycol Modified, Cross-Linked Starch Coated Iron Oxide Nanoparticles for Enhanced Magnetic Tumor Targeting

PubMed Central

Cole, Adam J.; David, Allan E.; Wang, Jianxin; Galbán, Craig J.; Hill, Hannah L.; Yang, Victor C.

2010-01-01

While successful magnetic tumor targeting of iron oxide nanoparticles has been achieved in a number of models, the rapid blood clearance of magnetically suitable particles by the reticuloendothelial system (RES) limits their availability for targeting. This work aimed to develop a long-circulating magnetic iron oxide nanoparticle (MNP) platform capable of sustained tumor exposure via the circulation and, thus, enhanced magnetic tumor targeting. Aminated, cross-linked starch (DN) and aminosilane (A) coated MNPs were successfully modified with 5 kDa (A5, D5) or 20 kDa (A20, D20) polyethylene glycol (PEG) chains using simple N-Hydroxysuccinimide (NHS) chemistry and characterized. Identical PEG-weight analogues between platforms (A5 & D5, A20 & D20) were similar in size (140–190 nm) and relative PEG labeling (1.5% of surface amines – A5/D5, 0.4% – A20/D20), with all PEG-MNPs possessing magnetization properties suitable for magnetic targeting. Candidate PEG-MNPs were studied in RES simulations in vitro to predict long-circulating character. D5 and D20 performed best showing sustained size stability in cell culture medium at 37°C and 7 (D20) to 10 (D5) fold less uptake in RAW264.7 macrophages when compared to previously targeted, unmodified starch MNPs (D). Observations in vitro were validated in vivo, with D5 (7.29 hr) and D20 (11.75 hr) showing much longer half-lives than D (0.12 hr). Improved plasma stability enhanced tumor MNP exposure 100 (D5) to 150 (D20) fold as measured by plasma AUC0-∞ Sustained tumor exposure over 24 hours was visually confirmed in a 9L-glioma rat model (12 mg Fe/kg) using magnetic resonance imaging (MRI). Findings indicate that both D5 and D20 are promising MNP platforms for enhanced magnetic tumor targeting, warranting further study in tumor models. PMID:21176955

Assessment of the mobile bag method for estimation of in vivo starch digestibility.

PubMed

Ghoorchi, T; Lund, P; Larsen, M; Hvelplund, T; Hansen-Møller, J; Weisbjerg, M R

2013-02-01

The objective was to assess the ability of the in situ mobile nylon bag method for predicting small intestinal and total tract starch digestibility. Starch disappearance was measured for 18 samples of different cereals and legumes subjected to different physical and chemical processing methods and compared with coherent in vivo digestibility. Starch disappearance was measured both with and without initial ruminal pre-incubation during 4 h. Bags were retrieved from either the ileal cannula or faeces. Two dry Danish Holstein cows fitted with rumen cannulas were used for rumen pre-incubations and two lactating Danish Holstein cows fitted with duodenal and ileal cannulas were used for intestinal incubations. Rumen pre-incubation had no significant effect on disappearance from bags recovered in faeces. The disappearance of legume starch was lower, both in the rumen and small intestine, compared with starch from barley, wheat, oats, ear maize and maize. Transit times of the mobile bags from duodenum to ileum were not significantly different between feeds. A weak positive correlation was found between in vivo small intestinal and total tract digestibility of starch and disappearance obtained using the mobile bag technique across a broad range of starch sources. Omitting two less conventional starch sources (NaOH wheat and xylose-treated barley) resulted in a high (0.87) correlation between total tract in vivo digestibility and mobile bag disappearance. The use of the mobile bag method for estimation of in vivo starch digestibility will therefore depend on the starch type.

Starch as a source, starch as a sink: the bifunctional role of starch in carbon allocation.

PubMed

MacNeill, Gregory J; Mehrpouyan, Sahar; Minow, Mark A A; Patterson, Jenelle A; Tetlow, Ian J; Emes, Michael J

2017-07-20

Starch commands a central role in the carbon budget of the majority of plants on earth, and its biological role changes during development and in response to the environment. Throughout the life of a plant, starch plays a dual role in carbon allocation, acting as both a source, releasing carbon reserves in leaves for growth and development, and as a sink, either as a dedicated starch store in its own right (in seeds and tubers), or as a temporary reserve of carbon contributing to sink strength, in organs such as flowers, fruits, and developing non-starchy seeds. The presence of starch in tissues and organs thus has a profound impact on the physiology of the growing plant as its synthesis and degradation governs the availability of free sugars, which in turn control various growth and developmental processes. This review attempts to summarize the large body of information currently available on starch metabolism and its relationship to wider aspects of carbon metabolism and plant nutrition. It highlights gaps in our knowledge and points to research areas that show promise for bioengineering and manipulation of starch metabolism in order to achieve more desirable phenotypes such as increased yield or plant biomass. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Butyrylation of Maize and Potato Starches and Characterization of the Products by Nuclear Magnetic Resonance and In Vitro Fermentation.

PubMed

Nielsen, Tina Skau; Canibe, Nuria; Larsen, Flemming Hofmann

2018-05-18

Intake of butyrylated starches may increase colonic butyrate supply, which can be of public health and clinical benefit by maintaining colonic health. The objective was to investigate if an organocatalytic method with tartaric acid as a catalyst could be applied to produce butyrylated products from different starch sources and to characterize their chemical structure and fermentation capability by using solid-state 13 C MAS NMR (magic angle spinning nuclear magnetic resonance) spectroscopy and an in vitro fermentation model, respectively. Low-amylose and high-amylose potato starch (LAPS and HAPS) and low-amylose and high-amylose maize starch (LAMS and HAMS) were subjected to organocatalytic butyrylation. This resulted in products with an increasing degree of substitution (DS) measured by heterogenous saponification and back titration with the HCl (chemical method) depending on reaction time. NMR analysis, however, showed that the major part of the acylation was induced by tartarate (75⁻89%) and only a minor part (11⁻25%) by butyrate. Generally, the chemical method overestimated the DS by 38% to 91% compared with the DS determination by NMR. Increasing the DS appeared to lower the in vitro fermentation capability of starches independent of the starch source and, therefore, do not seem to present a feasible method to deliver more butyrate to the colon than lower DS products.

Ecotoxicological assessment of flocculant modified soil for lake restoration using an integrated biotic toxicity index.

PubMed

Wang, Zhibin; Zhang, Honggang; Pan, Gang

2016-06-15

Flocculant modified soils/clays are being increasingly studied as geo-engineering materials for lake restoration and harmful algal bloom control. However, the potential impacts of adding these materials in aquatic ecological systems remain unclear. This study investigated the potential effects of chitosan, cationic starch, chitosan modified soils (MS-C) and cationic starch modified soils (MS-S) on the aquatic organisms by using a bioassay battery. The toxicity potential of these four flocculants was quantitatively assessed using an integrated biotic toxicity index (BTI). The test system includes four aquatic species, namely Chlorella vulgaris, Daphnia magna, Cyprinus carpio and Limnodrilus hoffmeisteri, which represent four trophic levels in the freshwater ecosystem. Results showed that median effect concentrations (EC50) of the MS-C and MS-S were 31-124 times higher than chitosan and cationic starch, respectively. D. magna was the most sensitive species to the four flocculants. Histological examination of C. carpio showed that significant pathological changes were found in gills. Different from chitosan and cationic starch, MS-C and MS-S significantly alleviated the acute toxicities of chitosan and cationic starch. The toxicity order of the four flocculants based on BTI were cationic starch > chitosan > MS-S > MS-C. The results suggested that BTI can be used as a quantitative and comparable indicator to assess biotic toxicity for aquatic geo-engineering materials. Chitosan or cationic starch modified soil/clay materials can be used at their optimal dosage without causing substantial adverse effects to the bioassay battery in aquatic ecosystem. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of carbohydrate/protein ratio on the microstructure and the barrier and sorption properties of wheat starch-whey protein blend edible films.

PubMed

Basiak, Ewelina; Lenart, Andrzej; Debeaufort, Frédéric

2017-02-01

Starch and whey protein isolate and their mixtures were used for making edible films. Moisture sorption isotherms, water vapour permeability, sorption of aroma compounds, microstructure, water contact angle and surface properties were investigated. With increasing protein content, the microstructure changes became more homogeneous. The water vapour permeability increases with both the humidity gradient and the starch content. For all films, the hygroscopicity increases with starch content. Surface properties change according to the starch/whey protein ratio and are mainly related to the polar component of the surface tension. Films composed of 80% starch and 20% whey proteins have more hydrophobic surfaces than the other films due to specific interactions. The effect of carbohydrate/protein ratio significantly influences the microstructure, the surface wettability and the barrier properties of wheat starch-whey protein blend films. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Impact of acid and oxidative modifications, single or dual, of sorghum starch on biodegradable films.

PubMed

Biduski, Bárbara; Silva, Francine Tavares da; Silva, Wyller Max da; Halal, Shanise Lisie de Mello El; Pinto, Vania Zanella; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-01-01

The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films. Copyright © 2016. Published by Elsevier Ltd.

Effect of a small amount of sodium carbonate on konjac glucomannan-induced changes in thermal behavior of wheat starch.

PubMed

Zhou, Yun; Winkworth-Smith, Charles G; Wang, Yu; Liang, Jianfen; Foster, Tim J; Cheng, Yongqiang

2014-12-19

The effects of konjac glucomannan (KGM) on thermal behavior of wheat starch have been studied in the presence of low concentrations of Na2CO3 (0.1-0.2 wt% of starch). Confocal laser scanning microscopy (CLSM) allows the visualization of the starch gelatinization process and granule remnants in starch pastes. Heating the starch dispersion in KGM-Na2CO3 solution significantly delays granule swelling and inhibits amylose leaching, whereas Na2CO3 alone, at the same concentration, has little effect. Na2CO3 assists KGM in producing the extremely high viscosity of starch paste, attributing to a less remarkable breakdown of viscosity in subsequent heating, and protecting starch granules against crystallite melting. The distinct partially networked film around the surface of starch granules is evident in the CLSM images. We propose that Na2CO3 could trigger the formation of complexes between KGM and starch polymers, which exerts a protective effect on granular structure and modifying gelatinization characteristics of the mixtures. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efficiency of fat deposition from non-starch polysaccharides, starch and unsaturated fat in pigs.

PubMed

Halas, Veronika; Babinszky, László; Dijkstra, Jan; Verstegen, Martin W A; Gerrits, Walter J J

2010-01-01

The aim was to evaluate under protein-limiting conditions the effect of different supplemental energy sources: fermentable NSP (fNSP), digestible starch (dStarch) and digestible unsaturated fat (dUFA), on marginal efficiency of fat deposition and distribution. A further aim was to determine whether the extra fat deposition from different energy sources, and its distribution in the body, depends on feeding level. A total of fifty-eight individually housed pigs (48 (SD 4) kg) were used in a 3 x 2 factorial design study, with three energy sources (0.2 MJ digestible energy (DE)/kg(0.75) per d of fNSP, dStarch and dUFA added to a control diet) at two feeding levels. Ten pigs were slaughtered at 48 (SD 4) kg body weight and treatment pigs at 106 (SD 3) kg body weight. Bodies were dissected and the chemical composition of each body fraction was determined. The effect of energy sources on fat and protein deposition was expressed relative to the control treatments within both energy intake levels based on a total of thirty-two observations in six treatments, and these marginal differences were subsequently treated as dependent variables. Results showed that preferential deposition of the supplemental energy intake in various fat depots did not depend on the energy source, and the extra fat deposition was similar at each feeding level. The marginal energetic transformation (energy retention; ER) of fNSP, dStarch and dUFA for fat retention (ERfat:DE) was 44, 52 and 49 % (P>0.05), respectively. Feeding level affected fat distribution, but source of energy did not change the relative partitioning of fat deposition. The present results do not support values of energetic efficiencies currently used in net energy-based systems.

Pre-exercise nutrition: the role of macronutrients, modified starches and supplements on metabolism and endurance performance.

PubMed

Ormsbee, Michael J; Bach, Christopher W; Baur, Daniel A

2014-04-29

Endurance athletes rarely compete in the fasted state, as this may compromise fuel stores. Thus, the timing and composition of the pre-exercise meal is a significant consideration for optimizing metabolism and subsequent endurance performance. Carbohydrate feedings prior to endurance exercise are common and have generally been shown to enhance performance, despite increasing insulin levels and reducing fat oxidation. These metabolic effects may be attenuated by consuming low glycemic index carbohydrates and/or modified starches before exercise. High fat meals seem to have beneficial metabolic effects (e.g., increasing fat oxidation and possibly sparing muscle glycogen). However, these effects do not necessarily translate into enhanced performance. Relatively little research has examined the effects of a pre-exercise high protein meal on subsequent performance, but there is some evidence to suggest enhanced pre-exercise glycogen synthesis and benefits to metabolism during exercise. Finally, various supplements (i.e., caffeine and beetroot juice) also warrant possible inclusion into pre-race nutrition for endurance athletes. Ultimately, further research is needed to optimize pre-exercise nutritional strategies for endurance performance.

Pre-Exercise Nutrition: The Role of Macronutrients, Modified Starches and Supplements on Metabolism and Endurance Performance

PubMed Central

Ormsbee, Michael J.; Bach, Christopher W.; Baur, Daniel A.

2014-01-01

Endurance athletes rarely compete in the fasted state, as this may compromise fuel stores. Thus, the timing and composition of the pre-exercise meal is a significant consideration for optimizing metabolism and subsequent endurance performance. Carbohydrate feedings prior to endurance exercise are common and have generally been shown to enhance performance, despite increasing insulin levels and reducing fat oxidation. These metabolic effects may be attenuated by consuming low glycemic index carbohydrates and/or modified starches before exercise. High fat meals seem to have beneficial metabolic effects (e.g., increasing fat oxidation and possibly sparing muscle glycogen). However, these effects do not necessarily translate into enhanced performance. Relatively little research has examined the effects of a pre-exercise high protein meal on subsequent performance, but there is some evidence to suggest enhanced pre-exercise glycogen synthesis and benefits to metabolism during exercise. Finally, various supplements (i.e., caffeine and beetroot juice) also warrant possible inclusion into pre-race nutrition for endurance athletes. Ultimately, further research is needed to optimize pre-exercise nutritional strategies for endurance performance. PMID:24787031

Acetylation of barnyardgrass starch with acetic anhydride under iodine catalysis.

PubMed

Bartz, Josiane; Goebel, Jorge Tiago; Giovanaz, Marcos Antônio; Zavareze, Elessandra da Rosa; Schirmer, Manoel Artigas; Dias, Alvaro Renato Guerra

2015-07-01

Barnyardgrass (Echinochloa crus-galli) is an invasive plant that is difficult to control and is found in abundance as part of the waste of the paddy industry. In this study, barnyardgrass starch was extracted and studied to obtain a novel starch with potential food and non-food applications. We report some of the physicochemical, functional and morphological properties as well as the effect of modifying this starch with acetic anhydride by catalysis with 1, 5 or 10mM of iodine. The extent of the introduction of acetyl groups increased with increasing iodine levels as catalyst. The shape of the granules remained unaltered, but there were low levels of surface corrosion and the overall relative crystallinity decreased. The pasting temperature, enthalpy and other gelatinisation temperatures were reduced by the modification. There was an increase in the viscosity of the pastes, except for the peak viscosity, which was strongly reduced in 10mM iodine. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preparation and Effect of Gamma Radiation on The Properties and Biodegradability of Poly(Styrene/Starch) Blends

NASA Astrophysics Data System (ADS)

Ali, H. E.; Abdel Ghaffar, A. M.

2017-01-01

Biodegradable blends based on Poly(styrene/starch) Poly(Sty/Starch) were prepared by the casting method using different contents of starch in the range of 0-20 wt% aiming at preparing disposable packaging materials. The prepared bio-blends were Characterized by Fourier transform infrared (FTIR), swelling behavior, mechanical properties, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). It was found that the swelling behavior slightly increased with increasing starch content and not exceeding 7.5%. The results showed that by increasing irradiation dose up to 5 kGy, the mechanical properties of the prepared PSty/10 wt% Starch blend film modified than other blend films, and hence it is selected. Also the water resistant increased, by irradiation of the selected PSty/10 wt% Starch blend film. The intermolecular hydrogen bonding interaction between Starch and PSty of the PSty/10 wt% Starch blend film promote a more homogenous blend film as shown in scanning electron microscopy (SEM). The prepared Poly(Sty/Starch) blends with different compositions and the selected irradiated PSty/10 wt% Starch blend were subjected to biodegradation in soil burial tests for 6 months using two different types of soils; agricultural and desert soils, then analyzed gravimetrically and by scanning electron microscopy (SEM). The results suggested that there is a possibility of using irradiated PSty/10 wt% Starch at a dose of 5 kGy as a potential candidate for packaging material.

Joint Effects of Granule Size and Degree of Substitution on Octenylsuccinated Sweet Potato Starch Granules As Pickering Emulsion Stabilizers.

PubMed

Li, Jinfeng; Ye, Fayin; Lei, Lin; Zhou, Yun; Zhao, Guohua

2018-05-02

The granules of sweet potato starch were size fractionated into three portions with significantly different median diameters ( D 50 ) of 6.67 (small-sized), 11.54 (medium-sized), and 16.96 μm (large-sized), respectively. Each portion was hydrophobized at the mass-based degrees of substitution (DS m ) of approximately 0.0095 (low), 0.0160 (medium), and 0.0230 (high). The Pickering emulsion-stabilizing capacities of modified granules were tested, and the resultant emulsions were characterized. The joint effects of granule size and DS m on emulsifying capacity (EC) were investigated by response surface methodology. For small-, medium-, and large-sized fractions, their highest emulsifying capacities are comparable but, respectively, encountered at high (0.0225), medium (0.0158), and low (0.0095) DS m levels. The emulsion droplet size increased with granule size, and the number of freely scattered granules in emulsions decreased with DS m . In addition, the term of surface density of the octenyl succinic group (SD -OSG ) was first proposed for modified starch granules, and it was proved better than DS m in interpreting the emulsifying capacities of starch granules with varying sizes. The present results implied that, as the particulate stabilizers, the optimal DS m of modified starch granules is size specific.

Low frequency ultrasonic-assisted hydrolysis of starch in the presence of α-amylase.

PubMed

Gaquere-Parker, Anne; Taylor, Tamera; Hutson, Raihannah; Rizzo, Ashley; Folds, Aubrey; Crittenden, Shastina; Zahoor, Neelam; Hussein, Bilal; Arruda, Aaron

2018-03-01

Hydrolysis of starch is an important process in the food industry and in the production of bioethanol or smaller carbohydrate molecules that can be used as starting blocks for chemical synthesis. Such hydrolysis can be enhanced by lowering the pH, heating the reaction mixture or catalyzing the reaction with enzymes. This study reports the effect of sonication on the reaction rate of starch hydrolysis at different temperatures, in the presence or absence of alpha-amylase. Starch Azure, a commercially available potato starch covalently linked with Remazol Brilliant Blue, has been chosen since its hydrolysis releases a blue dye, which concentration can be monitored by UV Vis spectroscopy. Ultrasounds, regardless of experimental conditions, provide the highest reaction rate for such hydrolysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Magnetorheological finishing of chemical-vapor deposited zinc sulfide via chemically and mechanically modified fluids

DOE PAGES

Salzman, Sivan; Romanofsky, Henry J.; Giannechini, Lucca J.; ...

2016-02-19

In this study, we describe the anisotropy in the material removal rate (MRR) of the polycrystalline, chemical-vapor deposited zinc sulfide (ZnS).We define the polycrystalline anisotropy via microhardness and chemical erosion tests for four crystallographic orientations of ZnS: (100), (110), (111), and (311). Anisotropy in the MRR was studied under magnetorheological finishing (MRF) conditions. Three chemically and mechanically modified magnetorheological (MR) fluids at pH values of 4, 5, and 6 were used to test the MRR variations among the four single-crystal planes. When polishing the single-crystal planes and the polycrystalline with pH 5 and pH 6MR fluids, variations were found inmore » the MRR among the four single-crystal planes and surface artifacts were observed on the polycrystalline material. When polishing the single-crystal planes and the polycrystalline with the modified MR fluid at pH 4, however, minimal variation was observed in the MRR among the four orientations and a reduction in surface artifacts was achieved on the polycrystalline material.« less

Physical and structural changes induced by high pressure on corn starch, rice flour and waxy rice flour.

PubMed

Cappa, Carola; Lucisano, Mara; Barbosa-Cánovas, Gustavo V; Mariotti, Manuela

2016-07-01

The impact of high pressure (HP) processing on corn starch, rice flour and waxy rice flour was investigated as a function of pressure level (400MPa; 600MPa), pressure holding time (5min; 10min), and temperature (20°C; 40°C). Samples were pre-conditioned (final moisture level: 40g/100g) before HP treatments. Both the HP treated and the untreated raw materials were evaluated for pasting properties and solvent retention capacity, and investigated by differential scanning calorimetry, X-ray diffractometry and environmental scanning electron microscopy. Different pasting behaviors and solvent retention capacities were evidenced according to the applied pressure. Corn starch presented a slower gelatinization trend when treated at 600MPa. Corn starch and rice flour treated at 600MPa showed a higher retention capacity of carbonate and lactic acid solvents, respectively. Differential scanning calorimetry and environmental scanning electron microscopy investigations highlighted that HP affected the starch structure of rice flour and corn starch. Few variations were evidenced in waxy rice flour. These results can assist in advancing the HP processing knowledge, as the possibility to successfully process raw samples in a very high sample-to-water concentration level was evidenced. This work investigates the effect of high pressure as a potential technique to modify the processing characteristics of starchy materials without using high temperature. In this case the starches were processed in the powder form - and not as a slurry as in previously reported studies - showing the flexibility of the HP treatment. The relevance for industrial application is the possibility to change the structure of flour starches, and thus modifying the processability of the mentioned products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of presence of sulphurdioxide on acetylation and sorption isotherm of acetylated starches from cultivars of cassava.

PubMed

Osundahunsi, Oluwatooyin Faramade; Seidu, Kudirat Titilope; Mueller, Rudolf

2014-05-15

Starches from cultivars of cassava were modified with acetic anhydride. Treatment with sulphurdioxide was compared with native. The starches were evaluated for functional properties and moisture isotherms were calculated. Addition of 3.5% acetic anhydride resulted in starches with DS of 1.66% and 3.25% in sweet and bitter cultivars. Sweet starch alone will be applicable for food. Least gelation concentrations for the native were 14% and 10% against 6% and 8% acetylated samples, respectively. Degree of substitution (DS) was reduced with SO2 by 45% and 39% in sweet and bitter cultivar with 150 mg/kg starch, respectively. Swelling power and solubility increased with DS. Exudates from samples varied. Monolayer values of the starches were between 1.05% and 9.16% under 18 °C and 30 °C that simulated distribution and storage. R(2) value of water adsorbed and water activity ranged from 50% to 97%. X-ray patterns were not disrupted. Copyright © 2014. Published by Elsevier Ltd.

Proximal composition and in vitro digestibility of starch in lima bean (Phaseolus lunatus) varieties.

PubMed

Bello-Pérez, Luis A; Sáyago-Ayerdi, Sonia G; Chávez-Murillo, Carolina E; Agama-Acevedo, Edith; Tovar, Juscelino

2007-11-01

Beans are rich and inexpensive sources of proteins and carbohydrates around the world, but particularly in developing countries. However, many legume varieties are still underutilized. In this study, physical characteristics of the seeds of three Phaseolus lunatus cultivars were characterized. Also, the chemical composition and starch digestibility in the cooked beans were assessed. 'Comba floja' variety exhibited the highest thousand-kernel weight whereas the lowest was found in 'comba violenta'. This agrees with seed dimensions: 'comba floja' had the Longest seeds (16.36 mm) and 'comba violenta' the shortest ones (13.98 mm). All samples exhibited high protein content, but levels in 'comba blanca' variety (216 g kg(-1)) were lower than the in other two cultivars. Total starch (370-380 g kg(-1)) and potentially available starch content (330-340 g kg(-1)) were similar in the three varieties. Resistant starch level in the cooked seeds ranged between 38 and 45 g kg(-1). Low enzymatic hydrolysis indices (HI) were recorded (30.2-35%), indicating a low digestion rate for Phaseolus lunatus starch. HI-based predicted glycemic indices ranged between 34% and 39%, which suggests a 'slow carbohydrate' feature for this legume. Phaseolus lunatus beans appear to be a good source of protein and slow-release carbohydrates with potential benefits for human health. Copyright © 2007 Society of Chemical Industry.

Starch nanoparticles resulting from combination of dry heating under mildly acidic conditions and homogenization.

PubMed

Kim, Jong Hun; Kim, Jiyeon; Park, Eun Young; Kim, Jong-Yea

2017-07-15

To modify starch granular structure, normal maize starch was subjected to dry heating with various amounts of 1.0M HCl (1.2, 1.4 or 1.6mL) and different treatment times (2, 4 or 8h). For all reaction conditions, at least 80% of the starch substance was recovered, and amylose and amylopectin B1 chains were preferentially cleaved. As acidic condition and/or treatment time increased, the treated granules were readily fragmented by homogenization. The treatment appeared to alter short-range crystalline structure (FT-IR), but long-range crystalline structure (XRD) remained intact. Homogenization for 60min fragmented the treated starch granules (subjected to reaction condition of 1.4mL/4h, 1.6mL/2h, and 1.6mL/4h) into nanoparticles consisting of individual platelet-like and spherical particles with diameters less than 100nm. However, the fragmentation caused obvious damage in the long-range crystalline structure of starch nanoparticles, while the short-range chain associations remained relatively intact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rheological properties of kuzu starch pastes with galactomannans.

PubMed

Jóźwiak, Bertrand; Orczykowska, Magdalena; Dziubiński, Marek

2018-04-01

The paper describes the effects of galactomannans on viscoelastic properties of commercial Japanese white kuzu starch pastes. The study included morphological, thermal and rheological analyses of the biopolymer. The results obtained in the form of storage modulus G '( ω ) and loss modulus G ″( ω ) were described by the modified fractional Kelvin-Voigt model with two springpot-type elements, created on the basis of differential calculus of fractional order and Fourier transform. It allowed to determine 17 material parameters providing a lot of additional information about structure and viscoelastic properties of the biopolymer in comparison to the classical analysis of oscillatory and creep tests. The study led to the conclusion that commercial Japanese white kuzu starch was so-called type II starch with a high pasting temperature of 75 °C and an average granule diameter equal to 10.9 μm. Rheological properties of the pastes depended on the galactose-to-mannose ratio in galactomannan molecule. The larger substitution degree, the higher viscosity, characteristic relaxation times, polydispersity index, gel stiffness, and the lower cross-linking density and average molecular weights. The presence of galactose side groups favored the hydration and immobilization of water molecules.

Properties Characterization of Chemically Modified Hemp Hurds

PubMed Central

Stevulova, Nadezda; Cigasova, Julia; Estokova, Adriana; Terpakova, Eva; Geffert, Anton; Kacik, Frantisek; Singovszka, Eva; Holub, Marian

2014-01-01

The effect of chemical treatment of hemp hurds slices in three solutions (EDTA (Ethylenediaminetetraacetic acid), NaOH and Ca(OH)2) on the properties of natural material was discussed in this paper. Changes in the morphology, chemical composition and structure as well as thermal stability of hemp hurds before and after their modification were investigated by using FTIR (Fourier transform infrared spectroscopy), XRD (X-ray powder diffraction analysis) and TG (thermogravimetry)/DSC (differential scanning calorimetry). Size exclusion chromatography (SEC) measurements were used for determination of degree of cellulose polymerization of hemp hurd samples. Chemical modification is related to the partial removal of non-cellulosic components of lignin, hemicellulose and pectin as well as waxes from the surface of hemp hurd slices. Another effect of the chemical treatment applied is connected with increasing the crystallinity index of cellulose determined by FTIR and XRD methods. Decrease in degree of cellulose polymerization and polydispersity index in chemically modified hemp hurds compared to the original sample was observed. Increase in thermal stability of treated hemp hurd was found. The most significant changes were observed in alkaline treated hemp hurds by NaOH. PMID:28788294

Packing properties of starch-based powders under mild mechanical stress.

PubMed

Zanardi, I; Gabbrielli, A; Travagli, V

2009-07-01

This study reports the ability to settle of commercial pharmaceutical grade starch samples, both native and pregelatinized. The experiments were carried out under different relative humidity (RH%) conditions and the packing properties were evaluated using both official pharmacopoeial monograph conditions and also modified conditions in order to give a deeper knowledge of tapping under mild mechanical stress. The technique adopted, simulating common pharmaceutical operating practices, appears to be useful to estimate some technologically relevant features of diluent powder materials. Moreover, a general mathematical function has been applied to the experimental data; this could be appropriate for adequately describing material settling patterns and offers practical parameters for characterizing starch powders within the context of a pharmaceutical quality system.

Mechanical properties and solubility in water of corn starch-collagen composite films: Effect of starch type and concentrations.

PubMed

Wang, Kun; Wang, Wenhang; Ye, Ran; Liu, Anjun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana

2017-02-01

This study investigated the possibility of enhancing the properties of collagen with three different maize starches: waxy maize starch, normal starch, and high amylose starch. Scanning electron microscopy images revealed that starch-collagen films had a rougher surface compared to pure collagen films which became smoother upon heating. Amylose starch and normal starch increased the tensile strength of unheated collagen films in both dry and wet states, while all starches increased tensile strength of collagen film by heating. Depending upon the amylose content and starch concentrations, film solubility in water decreased with the addition of starch. DSC thermograms demonstrated that addition of all starches improved the thermal stability of the collagen film. Moreover, X-ray diffraction results indicated that except for high amylose starch, the crystallinity of both starch and collagen was significantly decreased when subject to heating. FTIR spectra indicated that intermolecular interactions between starch and collagen were enhanced upon heating. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Hydrated Potato Starch on the Quality of Low-fat Ttoekgalbi (Korean Traditional Patty) Packaged in Modified Atmosphere Conditions during Storage.

PubMed

Muhlisin, S M Kang; Choi, W H; Lee, K T; Cheong, S H; Lee, S K

2012-05-01

This study was carried out to investigate the effects of hydrated potato starch on the quality of low-fat ttoekgalbi (Korean traditional patty) packaged in modified atmosphere conditions during storage. The ttoekgalbi was prepared from 53.2% lean beef, 13.9% lean pork, 9.3% pork fat, and 23.6% other ingredients. Two low-fat ttoekgalbi treatments were prepared by substituting pork fat with hydrated potato starch; either by 50% fat replacement (50% FR) or 100% fat replacement (100% FR). Both 50% and 100% FR increased the moisture, crude protein, and decreased fat content, cooking loss, and hardness. For MAP studies, 200 g of ttoekgalbi were placed on the tray and filled with gas composed of 70% O2: 30% CO2 (70% O2-MAP) and 30% CO2: 70% N2 (70% N2-MAP), and were stored at 5°C for 12 d. During the storage time, both 50% and 100% FR showed higher protein deterioration, while no differences were found in CIE a*, CIE L*, lipid oxidation, and bacterial counts in comparison to control. The ttoekgalbi with 70% O2-MAP was more red, lighter in color, and showed higher TBARS values compared with 70% N2-MAP. The meat with 70% N2-MAP showed lower aerobic bacterial counts in control than those with 70% O2-MAP. The lower anaerobic bacterial counts were observed only in 50% FR and 100% FR packed with 70% N2-MAP in comparison with 70% O2-MAP. In conclusion, the fat replacement with hydrated potato starch showed no negative effects on the quality of low fat ttoekgalbi during storage and 70% N2-MAP was better than 70% O2-MAP for low-fat ttoekgalbi packaging.

Structural characteristics and crystalline properties of lotus seed resistant starch and its prebiotic effects.

PubMed

Zhang, Yi; Zeng, Hongliang; Wang, Ying; Zeng, Shaoxiao; Zheng, Baodong

2014-07-15

Lotus seed resistant starch (LRS) is a type of retrograded starch that is commonly known as resistant starch type 3 (RS3). The structural and crystalline properties of unpurified LRS (NP-LRS3), enzyme purified LRS after drying (GP-LRS3), and enzyme purified LRS (ZP-LRS3) were characterized. The result showed that the molecular weights of NP-LRS3, GP-LRS3, and ZP-LRS3 were 0.102 × 10(6), 0.014 × 10(6), and 0.025 × 10(6)Da, respectively. Compared with native starch and high amylose maize starch (HAMS), LRS lacked the polarization cross and the irregularly shaped LRS granules had a rougher surface, B-type crystal structure, and greater level of molecular order. The FT-IR measurements indicated no differences in the chemical groups. Analysis by (13)C NMR indicated an increased propensity for double helix formation and higher crystallinity in LRS than in the two other types of starch. Moreover, LRS was more effective than either glucose or HAMS in promoting the proliferation of bifidobacteria. Copyright © 2014 Elsevier Ltd. All rights reserved.

Particle size distribution of rice flour affecting the starch enzymatic hydrolysis and hydration properties.

PubMed

de la Hera, Esther; Gomez, Manuel; Rosell, Cristina M

2013-10-15

Rice flour is becoming very attractive as raw material, but there is lack of information about the influence of particle size on its functional properties and starch digestibility. This study evaluates the degree of dependence of the rice flour functional properties, mainly derived from starch behavior, with the particle size distribution. Hydration properties of flours and gels and starch enzymatic hydrolysis of individual fractions were assessed. Particle size heterogeneity on rice flour significantly affected functional properties and starch features, at room temperature and also after gelatinization; and the extent of that effect was grain type dependent. Particle size heterogeneity on rice flour induces different pattern in starch enzymatic hydrolysis, with the long grain having slower hydrolysis as indicated the rate constant (k). No correlation between starch digestibility and hydration properties or the protein content was observed. It seems that in intact granules interactions with other grain components must be taken into account. Overall, particle size fractionation of rice flour might be advisable for selecting specific physico-chemical properties. Copyright © 2013. Published by Elsevier Ltd.

Contrasting effects of non-starch polysaccharide and resistant starch-based diets on the disposition and excretion of the food carcinogen, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), in a rat model.

PubMed

Ferguson, Lynnette R; Zhu, Shuotun; Kestell, Philip

2003-06-01

It has commonly been believed that increasing fibre in the diet should reduce the incidence of cancers, especially those of the colon and rectum. The earliest definitions of dietary fibre restricted the term to plant cell walls in which non-starch polysaccharides are key chemical components. However, new definitions encompass a wider range of materials, including starches resistant to digestion in the colon (resistant starches). Nevertheless, most definitions require that "dietary fibres" show physiological effects considered beneficial against cancer, including enhanced laxation and faecal bulking. On theoretical grounds, such properties might be expected to dilute the concentration of any carcinogen present and move it more rapidly through the colon, thereby reducing bioavailability. We have compared the properties of two dietary fibre preparations that are primarily non-starch polysaccharides with two resistant starch preparations for effects on carcinogen disposition in a rodent model. Although both preparations enhanced laxation and faecal bulking, only the non-starch polysaccharide preparation reduced carcinogen biovailability. Indeed, carcinogen biovailability was significantly enhanced by resistant starch. We suggest that there may be fundamental differences in the manner by which non-starch polysaccharides or resistant starches affect carcinogen disposition, and express concern that the events seen with the resistant starches [RS] are unlikely to be beneficial with respect to protection against cancer by exogenous carcinogens. Furthermore, the data reveal that the observation of enhanced laxation and faecal bulking does not necessarily imply a reduction in carcinogen bioavailability.

Biodegradation of polystyrene-graft-starch copolymers in three different types of soil.

PubMed

Nikolic, Vladimir; Velickovic, Sava; Popovic, Aleksandar

2014-01-01

Materials based on polystyrene and starch copolymers are used in food packaging, water pollution treatment, and textile industry, and their biodegradability is a desired characteristic. In order to examine the degradation patterns of modified, biodegradable derivates of polystyrene, which may keep its excellent technical features but be more environmentally friendly at the same time, polystyrene-graft-starch biomaterials obtained by emulsion polymerization in the presence of new type of initiator/activator pair (potassium persulfate/different amines) were subjected to 6-month biodegradation by burial method in three different types of commercially available soils: soil rich in humus and soil for cactus and orchid growing. Biodegradation was monitored by mass decrease, and the highest degradation rate was achieved in soil for cactus growing (81.30%). Statistical analysis proved that microorganisms in different soil samples have different ability of biodegradation, and there is a significant negative correlation between the share of polystyrene in copolymer and degree of biodegradation. Grafting of polystyrene on starch on one hand prevents complete degradation of starch that is present (with maximal percentage of degraded starch ranging from 55 to 93%), while on the other hand there is an upper limit of share of polystyrene in the copolymer (ranging from 37 to 77%) that is preventing biodegradation of degradable part of copolymers.

Chemical characteristics and volatile profile of genetically modified peanut cultivars.

PubMed

Ng, Ee Chin; Dunford, Nurhan T; Chenault, Kelly

2008-10-01

Genetic engineering has been used to modify peanut cultivars for improving agronomic performance and pest resistance. Food products developed through genetic engineering have to be assessed for their safety before approval for human consumption. Preservation of desirable chemical, flavor and aroma attributes of the peanut cultivars during the genetic modifications is critical for acceptance of genetically modified peanuts (GMP) by the food industry. Hence, the main objective of this study is to examine chemical characteristics and volatile profile of GMP. The genetically modified peanut cultivars, 188, 540 and 654 were obtained from the USDA-ARS in Stillwater, Oklahoma. The peanut variety Okrun was examined as a control. The volatile analysis was performed using a gas chromatograph/mass spectrometer (GC/MS) equipped with an olfactory detector. The peanut samples were also analyzed for their moisture, ash, protein, sugar and oil compositions. Experimental results showed that the variations in nutritional composition of peanut lines examined in this study were within the values reported for existing cultivars. There were minor differences in volatile profile among the samples. The implication of this study is significant, since it shows that peanut cultivars with greater pest and fungal resistance were successfully developed without major changes in their chemical characteristics.

Resistant starch improvement of rice starches under a combination of acid and heat-moisture treatments.

PubMed

Hung, Pham Van; Vien, Ngo Lam; Lan Phi, Nguyen Thi

2016-01-15

The effects of a combination of acid and heat-moisture treatment on formation of resistant starch (RS) and characteristics of high-amylose, normal and waxy rice starches were investigated in this study. The degrees of polymerization of the rice starches treated with citric acid, lactic acid or acetic acid were significantly reduced as compared to the native starches. The RS contents of acid and heat-moisture treated rice starches were in a range of 30.1-39.0%, significantly higher than those of native rice starches (6.3-10.2%) and those of heat-moisture treated rice starches (18.5-23.9%). The acid and heat-moisture treatments reduced swelling power and viscosity, but increased solubility of the starches, while the crystalline structure did not change. Among the organic acids used, citric acid had the most impact on starch characteristics and RS formation, followed by lactic acid and acetic acid. The results are useful in production of RS for functional food application. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization Properties of Environmentally Friendly Paper Coating Based Starch-Polyethylene glycol (PEG) Mixture

NASA Astrophysics Data System (ADS)

Galih Saputri, Diani; Khairuddin; Dwi Nurhayati, Nanik; Pham, Trinh

2017-11-01

The use of starch as biodegradable base material for packaging application was of great interest as an environmentally friendly alternative to the present use of polyethylene and polyvinyl chloride. However, starch tended to be brittle and had a lack of stability due to exposure to water. Several aproaches have been done to improve shellac properties including through chemical modification, mixing with polymers, clays, and plasticizers. The present study related to optimization of starch properties when mixing with polyethylene glycol (PEG) coated on the paper. The aim was to obtain the temperature and mixing time between starch and PEG so produced composites with optimal barrier properties. The composites of PEG/starch 10 % w/w were prepared using solvent casting and coated on paper surface, and dried in the oven for 12 hours at 40°C. Water Vapour Transmitter Rate (WVTR) (Payne cup method) showed that 70°C was the optimum temperature when mixing time was 30 minutes. Moreover, it showed that the optimum mixing time was 30 minutes when mixing temperature was 80 and 70 °C. Fourier Transform Infra Red (FTIR) showed a strong interaction between PEG400 and starch.

Direct fermentation of potato starch and potato residues to lactic acid by Geobacillus stearothermophilus under non-sterile conditions.

PubMed

Smerilli, Marina; Neureiter, Markus; Wurz, Stefan; Haas, Cornelia; Frühauf, Sabine; Fuchs, Werner

2015-04-01

Lactic acid is an important biorefinery platform chemical. The use of thermophilic amylolytic microorganisms to produce lactic acid by fermentation constitutes an efficient strategy to reduce operating costs, including raw materials and sterilization costs. A process for the thermophilic production of lactic acid by Geobacillus stearothermophilus directly from potato starch was characterized and optimized. Geobacillus stearothermophilus DSM 494 was selected out of 12 strains screened for amylolytic activity and the ability to form lactic acid as the major product of the anaerobic metabolism. In total more than 30 batches at 3-l scale were run at 60 °C under non-sterile conditions. The process developed produced 37 g L -1 optically pure (98%) L-lactic acid in 20 h from 50 g L -1 raw potato starch. As co-metabolites smaller amounts (<7% w/v) of acetate, formate and ethanol were formed. Yields of lactic acid increased from 66% to 81% when potato residues from food processing were used as a starchy substrate in place of raw potato starch. Potato starch and residues were successfully converted to lactic acid by G. stearothermophilus . The process described in this study provides major benefits in industrial applications and for the valorization of starch-rich waste streams. © 2015 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Chemical Demonstrations with Consumer Chemicals: The Black and White Reaction.

ERIC Educational Resources Information Center

Wright, Stephen W.

2002-01-01

Describes a dramatic chemical demonstration in which chemicals that are black and white combine to produce a colorless liquid. Reactants include tincture of iodine, bleach, white vinegar, Epsom salt, vitamin C tablets, and liquid laundry starch. (DDR)

An optically detectable CO2 sensor utilizing polyethylenimine and starch functionalized InGaN/GaN multiple quantum wells

NASA Astrophysics Data System (ADS)

Chen, Y. C.; Shih, H. Y.; Chen, J. Y.; Tan, W. J.; Chen, Y. F.

2013-07-01

An optically detectable gas sensor based on the high surface sensitivity of functionalized polyethylenimine/starch In0.15Ga0.85N/GaN strained semiconductor multiple quantum wells (MQWs) has been developed. Due to the excellent piezoelectricity of the MQWs, the change of surface charges caused by chemical interaction can introduce a strain and induce an internal field. In turn, it tilts the energy levels of the MQWs and modifies the optical properties. Through the measurement of the changes in photoluminescence as well as Raman scattering spectra under different concentrations of carbon dioxide gas, we demonstrate the feasibility and high sensitivity of the sensors derived from our methodology.

Chemically Modified Metal Oxide Nanostructure for Photoelectrochemical Water Splitting

NASA Astrophysics Data System (ADS)

Wang, Gongming

Hydrogen gas is chemical fuel with high energy density, and represents a clean, renewable and carbon-free burning fuel, which has the potential to solve the more and more urgent energy crisis in today's society. Inspired by natural photosynthesis, artificial photosynthesis to generate hydrogen energy has attracted a lot of attentions in the field of chemistry, physics and material. Photoelectrochemical water splitting based on semiconductors represents a green and low cost method to generate hydrogen fuel. However, the current overall efficiency of solar to hydrogen is quite low, due to some intrinsic limitations such as bandgap, diffusion distance, carrier lifetime and photostability of semiconductors. Although nanostructured semiconductors can improve their photoelectrochemical water splitting performance to some extent, by increasing electrolyte accessible area and shortening minority carrier diffusion distance, nanostructure engineering cannot change their intrinsic electronic properties. Recent development in chemically modified nanostructures such as surface catalyst decoration, element doping, plasmonic modification and interfacial hetero-junction design have led to significant advancement in the photoelectrochemical water splitting, by improving surface reaction kinetics and charge separation, transportation and collection efficiency. In this thesis, I will give a detailed discussion on the chemically modified metal oxide nanostructures for photoelectrocemical hydrogen generation, with a focus on the element doping, hydrogen treatment and catalyst modification. I have demonstrated nitrogen doping on ZnO and Ti doping on hematite can improve their photoelectrochemical performance. In addition, we found hydrogen treatment is a general and effective method to improve the photocatalytic performance, by increasing their carrier desities. Hydrogen treatment has been demonstrated on TiO2, WO3 and BiVO4. In the end, we also used electrochemical catalyt to modify

Quantification of high-power ultrasound induced damage on potato starch granules using light microscopy.

PubMed

Zuo, Yue Yue J; Hébraud, Pascal; Hemar, Yacine; Ashokkumar, Muthupandian

2012-05-01

A simple light microscopic technique was developed in order to quantify the damage inflicted by high-power low-frequency ultrasound (0-160 W, 20 kHz) treatment on potato starch granules in aqueous dispersions. The surface properties of the starch granules were modified using ethanol and SDS washing methods, which are known to displace proteins and lipids from the surface of the starch granules. The study showed that in the case of normal and ethanol-washed potato starch dispersions, two linear regions were observed. The number of defects first increased linearly with an increase in ultrasound power up to a threshold level. This was then followed by another linear dependence of the number of defects on the ultrasound power. The power threshold where the change-over occurred was higher for the ethanol-washed potato dispersions compared to non-washed potato dispersions. In the case of SDS-washed potato starch, although the increase in defects was linear with the ultrasound power, the power threshold for a second linear region was not observed. These results are discussed in terms of the different possible mechanisms of cavitation induced-damage (hydrodynamic shear stresses and micro-jetting) and by taking into account the hydrophobicity of the starch granule surface. Copyright © 2011 Elsevier B.V. All rights reserved.

Molecular disassembly of rice and lotus starches during thermal processing and its effect on starch digestibility.

PubMed

Wang, Shujun; Sun, Yue; Wang, Jinrong; Wang, Shuo; Copeland, Les

2016-02-01

The molecular disassembly of starch during thermal processing is a major determinant for the susceptibility of starch to enzymatic digestion. In the present study, the effects of thermal processing on the disassembly of the granular structure and the in vitro enzymatic digestibility of rice and lotus starches were investigated. After heating at 50 °C, rice and lotus starches did not show significant changes in granular morphology, long-range crystallinity and short-range molecular order. As the temperature increased to 60 °C, rice starch underwent a partial gelatinization followed by an incomplete disruption of granular morphology, crystallites and molecular order. In contrast, lotus starch was almost completely gelatinized at 60 °C. At 70 °C or higher, both starches were fully gelatinized with complete disruption of the micro and macro structures. Our results show that gelatinization greatly increased the in vitro enzymatic digestibility of both starches, but that the degree of disassembly of the starch structure during thermal processing was not a major determinant of the digestibility of gelatinized starch.

Enhancement of corrosion resistance of carbon steel by Dioscorea Hispida starch in NaCl

NASA Astrophysics Data System (ADS)

Zulhusni, M. D. M.; Othman, N. K.; Lazim, Azwan Mat

2015-09-01

Starch is a one of the most abundant natural product in the world and has the potential as corrosion inhibitor replacing harmful synthetic chemical based corrosion inhibitor. This research was aimed to examines the potential of starch extracted from local Malaysian wild yam (Dioscorea hispida), as corrosion inhibitor to carbon steel in NaCl media replicating sea water. By using gravimetric test and analysis, in which the carbon steel specimens were immersed in NaCl media for 24, 48 and 60 hours with the starch as corrosion inhibitor. the corrosion rate (mmpy) and inhibition efficiencies (%) was calculated. The results obtained showed decrease in corrosion rate as higher concentration of starch was employed. The inhibition efficiencies also shows an increasing manner up to 95.97 % as the concentration of the inhibitor increased.

Starch Spherulites Prepared by a Combination of Enzymatic and Acid Hydrolysis of Normal Corn Starch.

PubMed

Shang, Yaqian; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

2018-06-13

This paper describes a new method to prepare spherulites from normal corn starch by a combination of enzymatic (mixtures of α-amylase and amyloglucosidase) and acid hydrolysis followed by recrystallization of the hydrolyzed products. The resulting spherulites contained a higher proportion of chains with a degree of polymerization (DP) of 6-12 and a lower proportion of chains with DP of 25-36, compared to those of native starch. The spherulites had an even particle size of about 2 μm and a typical B-type crystallinity. The amounts of long- and short-range molecular order of double helices in starch spherulites were larger, but the quality of starch crystallites was poorer, compared to that of native starch. This study showed an efficient method for preparing starch spherulites with uniform granule morphology and small particle size from normal corn starch. The ratios of α-amylase and amyloglucosidase in enzymatic hydrolysis had little effect on the structure of the starch spherulites.

Adaptation of the cecal bacterial microbiome of growing pigs in response to resistant starch type 4.

PubMed

Metzler-Zebeli, Barbara U; Schmitz-Esser, Stephan; Mann, Evelyne; Grüll, Dietmar; Molnar, Timea; Zebeli, Qendrim

2015-12-01

Resistant starch (RS) exacerbates health benefits on the host via modulation of the gut bacterial community. By far, these effects have been less well explored for RS of type 4. This study aimed at gaining a community-wide insight into the impact of enzymatically modified starch (EMS) on the cecal microbiota and hindgut fermentation in growing pigs. Castrated male pigs (n = 12/diet; 29-kg body weight) were fed diets with either 70% EMS or control starch for 10 days. The bacterial profile of each cecal sample was determined by sequencing of the V345 region of the 16S rRNA gene using the Illumina MiSeq platform. EMS diet reduced short-chain fatty acid concentrations in cecum and proximal colon compared to the control diet. Linear discriminant analyses and K means clustering indicated diet-specific cecal community profiles, whereby diversity and species richness were not different among diets. Pigs showed host-specific variation in their most abundant phyla, Firmicutes (55%), Proteobacteria (35%), and Bacteroidetes (10%). The EMS diet decreased abundance of Ruminococcus, Parasutterella, Bilophila, Enterococcus, and Lactobacillus operational taxonomic units (OTU), whereas Meniscus and Actinobacillus OTU were increased compared to those with the control diet (P < 0.05). Quantitative PCR confirmed results for host effect on Enterobacteriaceae and diet effect on members of the Lactobacillus group. The presence of less cecal short-chain fatty acids and the imputed metabolic functions of the cecal microbiome suggested that EMS was less degradable for cecal bacteria than the control starch. The present EMS effects on the bacterial community profiles were different than the previously reported RS effects and can be linked to the chemical structure of EMS. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Distribution of branches in whole starches from maize mutants deficient in starch synthase III.

PubMed

Zhu, Fan; Bertoft, Eric; Seetharaman, Koushik

2014-05-21

An earlier study explored the possibility of analyzing the distribution of branches directly in native, whole starch without isolating the amylopectin component. The aim of this study was to explore if this approach can be extended to include starch mutants. Whole starches from du1 maize mutants deficient in starch synthase III (SSIII) with amylose content of ∼30-40% were characterized and compared with the wild type of the common genetic background W64A. Clusters were produced from whole starch by hydrolysis with α-amylase of Bacillus amyloliquefaciens. Their compositions of building blocks and chains were analyzed further by complete α-amylolysis and by debranching, respectively, whereafter the products were subjected to gel permeation and anion exchange chromatography. The size and structure of the clusters were compared with those of their isolated amylopectin component. Whereas the whole starch of the wild type sample had a branched structure similar to that of its amylopectin component, the results showed that the du1 mutation resulted in more singly branched building blocks in the whole starch compared to the isolated amylopectin. This suggested that amylose and/or intermediate materials in whole du1 starches likely contributed to the composition of branches. This study explored an alternative procedure to characterize the composition of branches in the whole starch without fractionating the components.

Effect of waxy rice flour and cassava starch on freeze-thaw stability of rice starch gels.

PubMed

Charoenrein, Sanguansri; Preechathammawong, Nutsuda

2012-10-01

Repeatedly frozen and thawed rice starch gel affects quality. This study investigated how incorporating waxy rice flour (WF) and cassava starch (CS) in rice starch gel affects factors used to measure quality. When rice starch gels containing 0-2% WF and CS were subjected to 5 freeze-thaw cycles, both WF and CS reduced the syneresis in first few cycles. However CS was more effective in reducing syneresis than WF. The different composite arrangement of rice starch with WF or CS caused different mechanisms associated with the rice starch gel retardation of retrogradation, reduced the spongy structure and lowered syneresis. Both swollen granules of rice starch and CS caused an increase in the hardness of the unfrozen and freeze-thawed starch gel while highly swollen WF granules caused softer gels. These results suggested that WF and CS were effective in preserving quality in frozen rice starch based products. Copyright © 2012 Elsevier Ltd. All rights reserved.

Physicochemical properties of maca starch.

PubMed

Zhang, Ling; Li, Guantian; Wang, Sunan; Yao, Weirong; Zhu, Fan

2017-03-01

Maca (Lepidium meyenii Walpers) is gaining research attention due to its unique bioactive properties. Starch is a major component of maca roots, thus representing a novel starch source. In this study, the properties of three maca starches (yellow, purple and black) were compared with commercially maize, cassava, and potato starches. The starch granule sizes ranged from 9.0 to 9.6μm, and the granules were irregularly oval. All the maca starches presented B-type X-ray diffraction patterns, with the relative degree of crystallinity ranging from 22.2 to 24.3%. The apparent amylose contents ranged from 21.0 to 21.3%. The onset gelatinization temperatures ranged from 47.1 to 47.5°C as indicated by differential scanning calorimetry. Significant differences were observed in the pasting properties and textural parameters among all of the studied starches. These characteristics suggest the utility of native maca starch in products subjected to low temperatures during food processing and other industrial applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays.

PubMed

Lichtenstein, Amir; Havivi, Ehud; Shacham, Ronen; Hahamy, Ehud; Leibovich, Ronit; Pevzner, Alexander; Krivitsky, Vadim; Davivi, Guy; Presman, Igor; Elnathan, Roey; Engel, Yoni; Flaxer, Eli; Patolsky, Fernando

2014-06-24

The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.

Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays

NASA Astrophysics Data System (ADS)

Lichtenstein, Amir; Havivi, Ehud; Shacham, Ronen; Hahamy, Ehud; Leibovich, Ronit; Pevzner, Alexander; Krivitsky, Vadim; Davivi, Guy; Presman, Igor; Elnathan, Roey; Engel, Yoni; Flaxer, Eli; Patolsky, Fernando

2014-06-01

The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.

Resistant starch type V formation in brown lentil (Lens culinaris Medikus) starch with different lipids/fatty acids.

PubMed

Okumus, Bahar Nur; Tacer-Caba, Zeynep; Kahraman, Kevser; Nilufer-Erdil, Dilara

2018-02-01

This study aimed to characterize the brown lentil (Lens culinaris Medikus) starch and investigate the formation of amylose-lipid complexes (Resistant Starch Type V) by the addition of different lipids/fatty acids (10%, w/w) to both raw and cooked starch samples. Resistant starch content (measured by the official method of AACCI (Method 32-40), using the resistant starch assay kit) of raw brown lentil starch (BLS) increased significantly by the additions of lipids/fatty acids, starch sample complexed with HSO (hydrogenated sunflower oil) (14.1±0.4%) being the highest. For the cooked starch/lipid complexes, more profound effect was evident (22.2-67.7%). Peak, breakdown and trough viscosity values of the amylose-lipid complexed starches were significantly lower than that of BLS (p<0.05), while significant decreases in the setback and final viscosities were only detected in oil samples, but not in fatty acids. Each lipid in concern exerted different effects on the digestibility of starch and amylose-lipid complex formation while having no substantial differential effects on the thermal properties of starch depicted by differential scanning calorimetry (DSC). Amylose-lipid complex formation with suitable fatty acids/lipids seems a promising way of increasing resistant starch content of food formulations. Although the applications being quite uncommon yet, brown lentil seems to have potential both as a starch and also as a resistant starch source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of xanthan, guar, CMC and gum acacia on functional properties of water chestnut (Trapa bispinosa) starch.

PubMed

Lutfi, Zubala; Nawab, Anjum; Alam, Feroz; Hasnain, Abid; Haider, Syed Zia

2017-10-01

This study was performed to determine the effect of xanthan, guar, CMC and gum acacia on functional and pasting properties of starch isolated from water chestnut (Trapa bispinosa). Morphological properties of water chestnut starch with CMC were studied by scanning electron microscopy (SEM). The addition of hydrocolloids significantly enhanced the solubility of water chestnut starch (WCS) while reduced swelling power and freeze-thaw stability. The hydrophilic tendency of WCS was increased by xanthan gum; however, with addition of gum acacia it decreased significantly. Starch was modified with guar and gum acacia exhibited highest% syneresis. Guar gum was found to be effective in increasing the clarity of water chestnut starch paste. The addition of CMC significantly reduced the pasting temperature of WCS indicating ease of gelatinization. The setback was accelerated in the presence of xanthan gum but gum acacia delayed this effect during the cooling of the starch paste. Only xanthan gum was found to be effective in increasing breakdown showing good paste stability of WCS. Copyright © 2017 Elsevier B.V. All rights reserved.

Investigations on structural and optical properties of starch capped ZnS nanoparticles synthesized by microwave irradiation method

NASA Astrophysics Data System (ADS)

Lalithadevi, B.; Mohan Rao, K.; Ramananda, D.

2018-05-01

Following a green synthesis method, zinc sulfide (ZnS) nanoparticles were prepared by chemical co-precipitation technique using starch as capping agent. Microwave irradiation was used as heating source. X-ray diffraction studies indicated that nanopowders obtained were polycrystalline possessing ZnS simple cubic structure. Transmission electron microscopic studies indicated that starch limits the agglomeration by steric stabilization. Interaction between ZnS and starch was confirmed by Fourier transform infrared spectroscopy as well as Raman scattering studies. Quantum size effects were observed in optical absorption studies while quenching of defect states on nanoparticles was improved with increase in starch addition as indicated by photoluminescence spectra.

The Effects of Treatments on Batu Banana Flour and Percentage of Wheat Substitution on The Resistant Starch, In Vitro Starch Digestibility Content and Palatability of Cookies Made with Banana (Musa balbisiana Colla) Flour

NASA Astrophysics Data System (ADS)

Ratnasari, D.; Rustanti, N.; Arifan, F.; Afifah, DN

2018-02-01

Diabetes mellitus (DM) is the most common endocrine disease worldwide. Resistant starch is polysaccharide that is recommended for DM patient diets. One of the staple crops containing resistant starch is banana. It is the fourth most important staple crop in the world and critical for food security, best suited plant in warm, frost-free, and coastal climates area. Among banana varieties, Batu bananas (Musa balbisiana Colla) had the highest content of resistant starch (~39%), but its use as a food ingredient is limited. Inclusion of Batu banana flour into cookies manufacturing would both increase the economic value of Batu bananas and provide alternative snacks for DM patients. Here we sought to examine whether cookies made with modified Batu banana flour would be a suitable snack for DM patients. This study used a completely randomized design with two factors: substitution of Batu banana flour (25%, 50%,75%) for wheat-based flour and Batu banana flour treatment methods (no treatment, autoclaving-cooling, autoclaving-cooling-spontaneous fermentation). The resistant starch and in vitro starch digestibility levels were analyzed using two-way ANOVA and Tukey test, whereas the acceptance level was analyzed by Friedman and Wilcoxon tests. The content of resistant starch and in vitro starch digestibility of the different treatments ranged from 3.10 to 15.79% and 16.03 to 52.59%, respectively. Both factors differed significantly (p<0.05) with respect to Batu banana flour substitution, but not to processing method (p>0.05). Meanwhile, palatability in terms of color, aroma, texture, and flavor differed significantly among the different treatments and starch contents (p<0.05). Together these results show that Batu banana flour could be a promising ingredient for the production of snacks suitable for consumption by DM patients. Keywords: Batu banana, cookies, resistant starch, in vitro starch digestibility

In vitro starch digestibility, pasting and textural properties of mung bean: effect of different processing methods.

PubMed

Kaur, Maninder; Sandhu, Kawaljit Singh; Ahlawat, RavinderPal; Sharma, Somesh

2015-03-01

Mung bean was subjected to different processing conditions (soaking, germination, cooking and autoclaving) and their textural, pasting and in vitro starch digestibility characteristics were studied. A significant reduction in textural properties (hardness, cohesiveness, gumminess and chewiness) after cooking and autoclaving treatment of mung bean was observed. Flours made from differently processed mung bean showed significant differences (P < 0.05) in their pastin g characteristics. Peak and final viscosity were the highest for flour from germinated mung bean whereas those made from autoclaved mung bean showed the lowest value. in vitro starch digestibility of mung bean flours was assessed enzymatically using modified Englyst method and the parameters studied were readily digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS) and total starch (TS) content. Various processing treatments increased the RDS contents of mung bean, while the SDS content was found to be the highest for soaked and the lowest for the autoclaved sample. Germinated sample showed higher amount of digestible starch (RDS + SDS) as compared to raw and soaked samples. Flours from raw and soaked samples showed significantly low starch hydrolysis rate at all the temperatures with total hydrolysis of 29.9 and 31.2 %, respectively at 180 min whereas cooked and autoclaved samples showed high hydrolysis rates with 50.2 and 53.8 % of these hydrolyzing within 30 min of hydrolysis.

Mixture design of rice flour, maize starch and wheat starch for optimization of gluten free bread quality.

PubMed

Mancebo, Camino M; Merino, Cristina; Martínez, Mario M; Gómez, Manuel

2015-10-01

Gluten-free bread production requires gluten-free flours or starches. Rice flour and maize starch are two of the most commonly used raw materials. Over recent years, gluten-free wheat starch is available on the market. The aim of this research was to optimize mixtures of rice flour, maize starch and wheat starch using an experimental mixture design. For this purpose, dough rheology and its fermentation behaviour were studied. Quality bread parameters such as specific volume, texture, cell structure, colour and acceptability were also analysed. Generally, starch incorporation reduced G* and increased the bread specific volume and cell density, but the breads obtained were paler than the rice flour breads. Comparing the starches, wheat starch breads had better overall acceptability and had a greater volume than maize-starch bread. The highest value for sensorial acceptability corresponded to the bread produced with a mixture of rice flour (59 g/100 g) and wheat starch (41 g/100 g).

Physical characterisation of high amylose maize starch and acylated high amylose maize starches.

PubMed

Lim, Ya-Mei; Hoobin, Pamela; Ying, DanYang; Burgar, Iko; Gooley, Paul R; Augustin, Mary Ann

2015-03-06

The particle size, water sorption properties and molecular mobility of high amylose maize starch (HAMS) and high amylose maize starch acylated with acetate (HAMSA), propionate (HAMSP) and butyrate (HAMSB) were investigated. Acylation increased the mean particle size (D(4,3)) and lowered the specific gravity (G) of the starch granules with an inverse relationship between the length of the fatty acid chain and particle size. Acylation of HAMS with fatty acids lowered the monolayer moisture content with the trend being HAMSBstarch granules by NMR spectroscopy with Carr-Purcell-Meiboom-Gill (CMPG) experiments showed that T2 long was reduced in acylated starches and that drying and storage of the starch granules further reduced T2 long. Analysis of the Free Induction Decay (FID) focussing on the short components of T2 (correlated to the solid matrix), indicated that drying and subsequent storage resulted in alterations of starch at 0.33a(w) and that these changes were reduced with acylation. In vitro enzymatic digestibility of heated starch dispersions by bacterial α-amylase was increased by acylation (HAMSstarch. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of starch nanoparticles

NASA Astrophysics Data System (ADS)

Szymońska, J.; Targosz-Korecka, M.; Krok, F.

2009-01-01

Nanomaterials already attract great interest because of their potential applications in technology, food science and medicine. Biomaterials are biodegradable and quite abundant in nature, so they are favoured over synthetic polymer based materials. Starch as a nontoxic, cheap and renewable raw material is particularly suitable for preparation of nanoparticles. In the paper, the structure and some physicochemical properties of potato and cassava starch particles of the size between 50 to 100 nm, obtained by mechanical treatment of native starch, were presented. We demonstrated, with the aim of the Scanning Electron Microscopy (SEM) and the non-contact Atomic Force Microscopy (nc-AFM), that the shape and dimensions of the obtained nanoparticles both potato and cassava starch fit the blocklets - previously proposed as basic structural features of native starch granules. This observation was supported by aqueous solubility and swelling power of the particles as well as their iodine binding capacity similar to those for amylopectin-type short branched polysaccharide species. Obtained results indicated that glycosidic bonds of the branch linkage points in the granule amorphous lamellae might be broken during the applied mechanical treatment. Thus the released amylopectin clusters could escape out of the granules. The starch nanoparticles, for their properties qualitatively different from those of native starch granules, could be utilized in new applications.

Chemical modification of Saccharomycopsis fibuligera R64 α-amylase to improve its stability against thermal, chelator, and proteolytic inactivation.

PubMed

Ismaya, Wangsa Tirta; Hasan, Khomaini; Kardi, Idar; Zainuri, Amalia; Rahmawaty, Rinrin Irma; Permanahadi, Satyawisnu; El Viera, Baiq Vera; Harinanto, Gunawan; Gaffar, Shabarni; Natalia, Dessy; Subroto, Toto; Soemitro, Soetijoso

2013-05-01

α-Amylase catalyzes hydrolysis of starch to oligosaccharides, which are further degraded to simple sugars. The enzyme has been widely used in food and textile industries and recently, in generation of renewable energy. An α-amylase from yeast Saccharomycopsis fibuligera R64 (Sfamy) is active at 50 °C and capable of degrading raw starch, making it attractive for the aforementioned applications. To improve its characteristics as well as to provide information for structural study ab initio, the enzyme was chemically modified by acid anhydrides (nonpolar groups), glyoxylic acid (GA) (polar group), dimethyl adipimidate (DMA) (cross-linking), and polyethylene glycol (PEG) (hydrophilization). Introduction of nonpolar groups increased enzyme stability up to 18 times, while modification by a cross-linking agent resulted in protection of the calcium ion, which is essential for enzyme activity and integrity. The hydrophilization with PEG resulted in protection against tryptic digestion. The chemical modification of Sfamy by various modifiers has thereby resulted in improvement of its characteristics and provided systematic information beneficial for structural study of the enzyme. An in silico structural study of the enzyme improved the interpretation of the results.

Effects of short-term heat stress at the grain formation stage on physicochemical properties of waxy maize starch.

PubMed

Gu, Xiaotian; Huang, Tianqi; Ding, Mengqiu; Lu, Weiping; Lu, Dalei

2018-02-01

Waxy maize (Zea mays L. sinensis Kulesh) suffers short-term exposure to high temperature during grain filling in southern China. The effects of such exposure are poorly understood. Starch granule size was increased by 5 days' short-term heat stress (35.0 °C) and the increase was higher when the stress was introduced early. Heat stress increased the iodine binding capacity of starches and no difference was observed among the three stages. Starch relative crystallinity was increased and swelling power was decreased only when heat stress was introduced early. Heat stress also increased the pasting viscosity, and this effect became more pronounced with later applications of stress. Heat stress reduced starch gelatinization enthalpy, and the reduction gradually increased with later exposures. Heat stress increased the gelatinization temperature and retrogradation enthalpy and percentage of the samples, with the increases being largest with earlier introduction of high temperature. Heat stress increased the pasting viscosities and retrogradation percentage of starch by causing change in granule size, amylopectin chain length distribution and crystallinity, and the effects observed were more severe with earlier introduction of heat stress after pollination. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Development of functional milk desserts enriched with resistant starch based on consumers' perception.

PubMed

Ares, Florencia; Arrarte, Eloísa; De León, Tania; Ares, Gastón; Gámbaro, Adriana

2012-10-01

Sensory characteristics play a key role in determining consumers' acceptance of functional foods. In this context, the aim of the present work was to apply a combination of sensory and consumer methodologies to the development of chocolate milk desserts enriched with resistant starch. Chocolate milk desserts containing modified waxy maize starch were formulated with six different concentrations of two types of resistant starch (which are part of insoluble dietary fiber). The desserts were evaluated by trained assessors using Quantitative Descriptive Analysis. Moreover, consumers scored their overall liking and willingness to purchase and answered an open-ended question. Resistant starch caused significant changes in the sensory characteristics of the desserts and a significant decrease in consumers' overall liking and willingness to purchase. Consumer data was analyzed applying survival analysis on overall liking scores, considering the risk on consumers liking and willing to purchase the functional products less than their regular counterparts. The proposed methodologies proved to be useful to develop functional foods taking into account consumers' perception, which could increase their success in the market.

Study of chloride ion transport of composite by using cement and starch as a binder

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armynah, Bidayatul; Halide, Halmar; Zahrawani,

This study presents the chemical bonding and the structural properties of composites from accelerator chloride test migration (ACTM). The volume fractions between binder (cement and starch) and charcoal in composites are 20:80 and 60:40. The effect of the binder to the chemical composition, chemical bonding, and structural properties before and after chloride ion passing through the composites was determined by X-ray fluorescence (XRF), by Fourier transform infra-red (FTIR), and x-ray diffraction (XRD), respectively. From the XRD data, XRF data, and the FTIR data shows the amount of chemical composition, the type of binding, and the structure of composites are dependingmore » on the type of binder. The amount of chloride migration using starch as binder is higher than that of cement as a binder due to the density effects.« less

Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism

PubMed Central

Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H.; Schwahn, Kevin; Fernie, Alisdair R.; Mateiu, Ramona V.; Blennow, Andreas

2016-01-01

Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

Altering the rate of glucose release from starch-based foods by spray-drying with an extract from barley.

PubMed

Razzaq, Hussam A A; Sutton, Kevin H; Motoi, Lidia

2013-08-30

Health outcomes associated with sustained elevated blood glucose may be better managed by limiting glucose availability for uptake. Glucose release from consumed starch may be altered using various methods, but many are not suitable for high-carbohydrate foods. This study describes an approach to protect starch granules, while generally maintaining their physical characteristics, with an extract from barley using spray-drying. The use of the extract resulted in the coating of the starch granules with a film-like material composed of β-glucans and proteins. This coincided with a reduction in starch digestion and a significant increase in the indigestible (resistant) starch component. Substitution of the starch component in a model snack bar by the coated starch was also associated with lowering starch digestion in the bar. The barley extract provides a physical barrier that may limit the exposure of starch to the digestive enzymes and water, with a consequent reduction in starch digestion and the rate of glucose release. It is possible, therefore, to produce wheat starch with lower digestibility and glucose release rate that may be used as a healthier substitute in high-carbohydrate foods by coating the granules with polymers extracted from barley cereals through spray-drying. © 2013 Society of Chemical Industry.

Starch Origin and Thermal Processing Affect Starch Digestion in a Minipig Model of Pancreatic Exocrine Insufficiency.

PubMed

Mößeler, Anne; Vagt, Sandra; Beyerbach, Martin; Kamphues, Josef

2015-01-01

Although steatorrhea is the most obvious symptom of pancreatic exocrine insufficiency (PEI), enzymatic digestion of protein and starch is also impaired. Low praecaecal digestibility of starch causes a forced microbial fermentation accounting for energy losses and meteorism. To optimise dietetic measures, knowledge of praecaecal digestibility of starch is needed but such information from PEI patients is rare. Minipigs fitted with an ileocaecal fistula with (n = 3) or without (n = 3) pancreatic duct ligation (PL) were used to estimate the rate of praecaecal disappearance (pcD) of starch. Different botanical sources of starch (rice, amaranth, potato, and pea) were fed either raw or cooked. In the controls (C), there was an almost complete pcD (>92%) except for potato starch (61.5%) which was significantly lower. In PL pcD of raw starch was significantly lower for all sources of starch except for amaranth (87.9%). Thermal processing increased pcD in PL, reaching values of C for starch from rice, potato, and pea. This study clearly underlines the need for precise specification of starch used for patients with specific dietetic needs like PEI. Data should be generated in suitable animal models or patients as tests in healthy individuals would not have given similar conclusions.

Direct fermentation of potato starch and potato residues to lactic acid by Geobacillus stearothermophilus under non-sterile conditions

PubMed Central

Smerilli, Marina; Neureiter, Markus; Wurz, Stefan; Haas, Cornelia; Frühauf, Sabine; Fuchs, Werner

2015-01-01

BACKGROUND Lactic acid is an important biorefinery platform chemical. The use of thermophilic amylolytic microorganisms to produce lactic acid by fermentation constitutes an efficient strategy to reduce operating costs, including raw materials and sterilization costs. RESULTS A process for the thermophilic production of lactic acid by Geobacillus stearothermophilus directly from potato starch was characterized and optimized. Geobacillus stearothermophilus DSM 494 was selected out of 12 strains screened for amylolytic activity and the ability to form lactic acid as the major product of the anaerobic metabolism. In total more than 30 batches at 3–l scale were run at 60 °C under non-sterile conditions. The process developed produced 37 g L−1 optically pure (98%) L-lactic acid in 20 h from 50 g L−1 raw potato starch. As co-metabolites smaller amounts (<7% w/v) of acetate, formate and ethanol were formed. Yields of lactic acid increased from 66% to 81% when potato residues from food processing were used as a starchy substrate in place of raw potato starch. CONCLUSIONS Potato starch and residues were successfully converted to lactic acid by G. stearothermophilus. The process described in this study provides major benefits in industrial applications and for the valorization of starch-rich waste streams. © 2015 The Authors.Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:25937690

Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

PubMed Central

Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

2016-01-01

Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms. PMID:26837707

Lignocellulosic ethanol production by starch-base industrial yeast under PEG detoxification

NASA Astrophysics Data System (ADS)

Liu, Xiumei; Xu, Wenjuan; Mao, Liaoyuan; Zhang, Chao; Yan, Peifang; Xu, Zhanwei; Zhang, Z. Conrad

2016-02-01

Cellulosic ethanol production from lignocellulosic biomass offers a sustainable solution for transition from fossil based fuels to renewable alternatives. However, a few long-standing technical challenges remain to be addressed in the development of an economically viable fermentation process from lignocellulose. Such challenges include the needs to improve yeast tolerance to toxic inhibitory compounds and to achieve high fermentation efficiency with minimum detoxification steps after a simple biomass pretreatment. Here we report an in-situ detoxification strategy by PEG exo-protection of an industrial dry yeast (starch-base). The exo-protected yeast cells displayed remarkably boosted vitality with high tolerance to toxic inhibitory compounds, and with largely improved ethanol productivity from crude hydrolysate derived from a pretreated lignocellulose. The PEG chemical exo-protection makes the industrial S. cerevisiae yeast directly applicable for the production of cellulosic ethanol with substantially improved productivity and yield, without of the need to use genetically modified microorganisms.

Morphological, Thermal, and Rheological Properties of Starches from Maize Mutants Deficient in Starch Synthase III.

PubMed

Zhu, Fan; Bertoft, Eric; Li, Guantian

2016-08-31

Morphological, thermal, and rheological properties of starches from maize mutants deficient in starch synthase III (SSIII) with a common genetic background (W64A) were studied and compared with the wild type. SSIII deficiency reduced granule size of the starches from 16.7 to ∼11 μm (volume-weighted mean). Thermal analysis showed that SSIII deficiency decreased the enthalpy change of starch during gelatinization. Steady shear analysis showed that SSIII deficiency decreased the consistency coefficient and yield stress during steady shearing, whereas additional deficiency in granule-bound starch synthase (GBSS) increased these values. Dynamic oscillatory analysis showed that SSIII deficiency decreased G' at 90 °C during heating and increased it when the paste was cooled to 25 °C at 40 Hz during a frequency sweep. Additional GBSS deficiency further decreased the G'. Structural and compositional bases responsible for these changes in physical properties of the starches are discussed. This study highlighted the relationship between SSIII and some physicochemical properties of maize starch.

Starch Metabolism in Arabidopsis

PubMed Central

Streb, Sebastian; Zeeman, Samuel C.

2012-01-01

Starch is the major non-structural carbohydrate in plants. It serves as an important store of carbon that fuels plant metabolism and growth when they are unable to photosynthesise. This storage can be in leaves and other green tissues, where it is degraded during the night, or in heterotrophic tissues such as roots, seeds and tubers, where it is stored over longer time periods. Arabidopsis accumulates starch in many of its tissues, but mostly in its leaves during the day. It has proven to be a powerful genetic system for discovering how starch is synthesised and degraded, and new proteins and processes have been discovered. Such work has major significance for our starch crops, whose yield and quality could be improved by the application of this knowledge. Research into Arabidopsis starch metabolism has begun to reveal how its daily turnover is integrated into the rest of metabolism and adapted to the environmental conditions. Furthermore, Arabidopsis mutant lines deficient in starch metabolism have been employed as tools to study other biological processes ranging from sugar sensing to gravitropism and flowering time control. This review gives a detailed account of the use of Arabidopsis to study starch metabolism. It describes the major discoveries made and presents an overview of our understanding today, together with some as-yet unresolved questions. PMID:23393426

Transcriptional analysis of Myceliophthora thermophila on soluble starch and role of regulator AmyR on polysaccharide degradation.

PubMed

Xu, Guanbao; Li, Jingen; Liu, Qian; Sun, Wenliang; Jiang, Min; Tian, Chaoguang

2018-05-24

Thermophilic fungus Myceliophthora thermophila has great capacity for biomass degradation and is an attractive option for use as cell factory to produce chemicals directly from renewable polysaccharides, such as starch, rather than monomer glucose. To date, there has been no transcriptomic analysis of this thermophilic fungus on starch. This study determined the transcriptomic profile of M. thermophila responding to soluble starch and a 342-gene set was identified as a "starch regulon", including the major amylolytic enzyme (Mycth_72393). Its overexpression led to increased amylase activities on starch by 35%. Furthermore, overexpressing the key amylolytic enzyme regulator AmyR in M. thermophila significantly increased amylase activity by 30%. Deletion of amyR by the CRISPR/Cas9 system led to the relief of carbon catabolite repression and 3-fold increased lignocellulase activities on cellulose. This study will accelerate rational fungal strain engineering for biochemical production from biomass substrates such as raw corn starch and even crop straw. Copyright © 2018 Elsevier Ltd. All rights reserved.

Concerted suppression of all starch branching enzyme genes in barley produces amylose-only starch granules

PubMed Central

2012-01-01

Background Starch is stored in higher plants as granules composed of semi-crystalline amylopectin and amorphous amylose. Starch granules provide energy for the plant during dark periods and for germination of seeds and tubers. Dietary starch is also a highly glycemic carbohydrate being degraded to glucose and rapidly absorbed in the small intestine. But a portion of dietary starch, termed “resistant starch” (RS) escapes digestion and reaches the large intestine, where it is fermented by colonic bacteria producing short chain fatty acids (SCFA) which are linked to several health benefits. The RS is preferentially derived from amylose, which can be increased by suppressing amylopectin synthesis by silencing of starch branching enzymes (SBEs). However all the previous works attempting the production of high RS crops resulted in only partly increased amylose-content and/or significant yield loss. Results In this study we invented a new method for silencing of multiple genes. Using a chimeric RNAi hairpin we simultaneously suppressed all genes coding for starch branching enzymes (SBE I, SBE IIa, SBE IIb) in barley (Hordeum vulgare L.), resulting in production of amylose-only starch granules in the endosperm. This trait was segregating 3:1. Amylose-only starch granules were irregularly shaped and showed peculiar thermal properties and crystallinity. Transgenic lines retained high-yield possibly due to a pleiotropic upregualtion of other starch biosynthetic genes compensating the SBEs loss. For gelatinized starch, a very high content of RS (65 %) was observed, which is 2.2-fold higher than control (29%). The amylose-only grains germinated with same frequency as control grains. However, initial growth was delayed in young plants. Conclusions This is the first time that pure amylose has been generated with high yield in a living organism. This was achieved by a new method of simultaneous suppression of the entire complement of genes encoding starch branching enzymes. We

Gradually Decreasing Starch Branching Enzyme Expression Is Responsible for the Formation of Heterogeneous Starch Granules1[OPEN

PubMed Central

Hu, Pan; Chen, Zichun

2018-01-01

Rice (Oryza sativa) endosperm is mainly occupied by homogeneous polygonal starch from inside to outside. However, morphologically different (heterogeneous) starches have been identified in some rice mutants. How these heterogeneous starches form remains unknown. A high-amylose rice line (TRS) generated through the antisense inhibition of starch branching synthase I (SBEI) and SBEIIb contains four heterogeneous starches: polygonal, aggregate, elongated, and hollow starch; these starches are regionally distributed in the endosperm from inside to outside. Here, we investigated the relationship between SBE dosage and the morphological architecture of heterogeneous starches in TRS endosperm from the view of the molecular structure of starch. The results indicated that their molecular structures underwent regular changes, including gradually increasing true amylose content but decreasing amylopectin content and gradually increasing the ratio of amylopectin long chain but decreasing the ratio of amylopectin short chain. Granule-bound starch synthase I (GBSSI) amounts in the four heterogeneous starches were not significantly different from each other, but SBEI, SBEIIa, and SBEIIb showed a gradually decreasing trend. Further immunostaining analysis revealed that the gradually decreasing SBEs acting on the formation of the four heterogeneous granules were mainly due to the spatial distribution of the three SBEs in the endosperm. It was suggested that the decreased amylopectin in starch might remove steric hindrance and provide extra space for abundant amylose accumulation when the GBSSI amount was not elevated. Furthermore, extra amylose coupled with altered amylopectin structure possibly led to morphological changes in heterogeneous granules. PMID:29133372

Slowly digestible waxy maize starch prepared by octenyl succinic anhydride esterification and heat-moisture treatment: glycemic response and mechanism.

PubMed

He, Jinhua; Liu, Jie; Zhang, Genyi

2008-01-01

The mechanism and molecular structure of the slowly digestible waxy maize starch prepared by octenyl succinic anhydride (OSA) esterification and heat-moisture treatment were investigated. The in vitro Englyst test showed a proportion of 28.3% slowly digestible starch (SDS) when waxy maize starch was esterified with 3% OSA (starch weight based, and it is named OSA-starch), and a highest SDS content of 42.8% was obtained after OSA-starch (10% moisture) was further heated at 120 degrees C for 4 h (named HOSA-starch). The in vivo glycemic response of HOSA-starch, which showed a delayed appearance of blood glucose peak and a significant reduction (32.2%) of the peak glucose concentration, further confirmed its slow digestion property. Amylopectin debranching analysis revealed HOSA-starch had the highest resistance to debranching enzymes of isoamylase and pullulanase, and a simultaneous decrease of K m and V m (enzyme kinetics) was also shown when HOSA-starch was digested by either alpha-amylase or amyloglucosidase, indicating that the slow digestion of HOSA-starch resulted from an uncompetitive inhibition of enzyme activity during digestion. Size exclusion chromatography analysis of HOSA-starch showed fragmented amylopectin molecules with more nonreducing ends that are favorable for RS conversion to SDS by the action of amyloglucosidase in the Englyst test. Further solubility analysis indicates that the water-insolubility of HOSA-starch is caused by OSA-mediated cross-linking of amylopectin and the hydrophobic interaction between OSA-modified starch molecules. The water-insolubility of HOSA-starch would decrease its enzyme accessibility, and the digestion products with attached OSA molecules might also directly act as the uncompetitive inhibitor to reduce the enzyme activity leading to a slow digestion of HOSA-starch.

Cecropia peltata Accumulates Starch or Soluble Glycogen by Differentially Regulating Starch Biosynthetic Genes[W][OA

PubMed Central

Bischof, Sylvain; Umhang, Martin; Eicke, Simona; Streb, Sebastian; Qi, Weihong; Zeeman, Samuel C.

2013-01-01

The branched glucans glycogen and starch are the most widespread storage carbohydrates in living organisms. The production of semicrystalline starch granules in plants is more complex than that of small, soluble glycogen particles in microbes and animals. However, the factors determining whether glycogen or starch is formed are not fully understood. The tropical tree Cecropia peltata is a rare example of an organism able to make either polymer type. Electron micrographs and quantitative measurements show that glycogen accumulates to very high levels in specialized myrmecophytic structures (Müllerian bodies), whereas starch accumulates in leaves. Compared with polymers comprising leaf starch, glycogen is more highly branched and has shorter branches—factors that prevent crystallization and explain its solubility. RNA sequencing and quantitative shotgun proteomics reveal that isoforms of all three classes of glucan biosynthetic enzyme (starch/glycogen synthases, branching enzymes, and debranching enzymes) are differentially expressed in Müllerian bodies and leaves, providing a system-wide view of the quantitative programming of storage carbohydrate metabolism. This work will prompt targeted analysis in model organisms and cross-species comparisons. Finally, as starch is the major carbohydrate used for food and industrial applications worldwide, these data provide a basis for manipulating starch biosynthesis in crops to synthesize tailor-made polyglucans. PMID:23632447

Measurement of resistant starch by enzymatic digestion in starch and selected plant materials: collaborative study.

PubMed

McCleary, Barry V; McNally, Marian; Rossiter, Patricia

2002-01-01

Interlaboratory performance statistics was determined for a method developed to measure the resistant starch (RS) content of selected plant food products and a range of commercial starch samples. Food materials examined contained RS (cooked kidney beans, green banana, and corn flakes) and commercial starches, most of which naturally contain, or were processed to yield, elevated RS levels. The method evaluated was optimized to yield RS values in agreement with those reported for in vivo studies. Thirty-seven laboratories tested 8 pairs of blind duplicate starch or plant material samples with RS values between 0.6 (regular maize starch) and 64% (fresh weight basis). For matrixes excluding regular maize starch, repeatability relative standard deviation (RSDr) values ranged from 1.97 to 4.2%, and reproducibility relative standard deviation (RSDR) values ranged from 4.58 to 10.9%. The range of applicability of the test is 2-64% RS. The method is not suitable for products with <1% RS (e.g., regular maize starch; 0.6% RS). For such products, RSDr and RSDR values are unacceptably high.

Structural characteristics of slowly digestible starch and resistant starch isolated from heat-moisture treated waxy potato starch.

PubMed

Lee, Chang Joo; Moon, Tae Wha

2015-07-10

The objective of this study was to investigate the structural characteristics of slowly digestible starch (SDS) and resistant starch (RS) fractions isolated from heat-moisture treated waxy potato starch. The waxy potato starch with 25.7% moisture content was heated at 120°C for 5.3h. Scanning electron micrographs of the cross sections of RS and SDS+RS fractions revealed a growth ring structure. The branch chain-length distribution of debranched amylopectin from the RS fraction had a higher proportion of long chains (DP ≥ 37) than the SDS+RS fraction. The X-ray diffraction intensities of RS and SDS+RS fractions were increased compared to the control. The SDS+RS fraction showed a lower gelatinization enthalpy than the control while the RS fraction had a higher value than the SDS+RS fraction. In this study we showed the RS fraction is composed mainly of crystalline structure and the SDS fraction consists of weak crystallites and amorphous regions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterisation of cationic potato starch by asymmetrical flow field-flow fractionation. Influence of ionic strength and degree of substitution.

PubMed

Santacruz, Stalin

2014-06-15

The properties of a paper sheet depend on the absorption together with the physico-chemical properties of additives used in the paper processing. The effect of ionic strength and degree of substitution of cationic potato starch on the elution pattern of asymmetrical flow field-flow fractionation was analysed. The effect of starch derivatisation, in either dry or wet phase, was also investigated. Average molar mass showed no difference between the starches obtained from the two derivatisation processes. Apparent densities showed that dry cationic starch had higher density than wet cationic starch for a hydrodynamic radius between 50 and 100 nm. Elution times of native and three cationic starches increased when the ionic strength increased from 50 to 100mM. No differences in the molar mass among cationic starches with different degree of substitution suggested no degradation due to a derivatisation process. Large sample loads can be used at 100mM without overloading. Copyright © 2014 Elsevier Ltd. All rights reserved.

Novel Bioengineered Cassava Expressing an Archaeal Starch Degradation System and a Bacterial ADP-Glucose Pyrophosphorylase for Starch Self-Digestibility and Yield Increase.

PubMed

Ligaba-Osena, Ayalew; Jones, Jenna; Donkor, Emmanuel; Chandrayan, Sanjeev; Pole, Farris; Wu, Chang-Hao; Vieille, Claire; Adams, Michael W W; Hankoua, Bertrand B

2018-01-01

To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava ( Manihot esculenta ), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus , together with the gene encoding a modified ADP-glucose pyrophosphorylase ( glgC ) from Escherichia coli , were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability.

Chemical and Conformational Diversity of Modified Nucleosides Affects tRNA Structure and Function.

PubMed

Väre, Ville Y P; Eruysal, Emily R; Narendran, Amithi; Sarachan, Kathryn L; Agris, Paul F

2017-03-16

RNAs are central to all gene expression through the control of protein synthesis. Four major nucleosides, adenosine, guanosine, cytidine and uridine, compose RNAs and provide sequence variation, but are limited in contributions to structural variation as well as distinct chemical properties. The ability of RNAs to play multiple roles in cellular metabolism is made possible by extensive variation in length, conformational dynamics, and the over 100 post-transcriptional modifications. There are several reviews of the biochemical pathways leading to RNA modification, but the physicochemical nature of modified nucleosides and how they facilitate RNA function is of keen interest, particularly with regard to the contributions of modified nucleosides. Transfer RNAs (tRNAs) are the most extensively modified RNAs. The diversity of modifications provide versatility to the chemical and structural environments. The added chemistry, conformation and dynamics of modified nucleosides occurring at the termini of stems in tRNA's cloverleaf secondary structure affect the global three-dimensional conformation, produce unique recognition determinants for macromolecules to recognize tRNAs, and affect the accurate and efficient decoding ability of tRNAs. This review will discuss the impact of specific chemical moieties on the structure, stability, electrochemical properties, and function of tRNAs.

Pollen source effects on growth of kernel structures and embryo chemical compounds in maize.

PubMed

Tanaka, W; Mantese, A I; Maddonni, G A

2009-08-01

Previous studies have reported effects of pollen source on the oil concentration of maize (Zea mays) kernels through modifications to both the embryo/kernel ratio and embryo oil concentration. The present study expands upon previous analyses by addressing pollen source effects on the growth of kernel structures (i.e. pericarp, endosperm and embryo), allocation of embryo chemical constituents (i.e. oil, protein, starch and soluble sugars), and the anatomy and histology of the embryos. Maize kernels with different oil concentration were obtained from pollinations with two parental genotypes of contrasting oil concentration. The dynamics of the growth of kernel structures and allocation of embryo chemical constituents were analysed during the post-flowering period. Mature kernels were dissected to study the anatomy (embryonic axis and scutellum) and histology [cell number and cell size of the scutellums, presence of sub-cellular structures in scutellum tissue (starch granules, oil and protein bodies)] of the embryos. Plants of all crosses exhibited a similar kernel number and kernel weight. Pollen source modified neither the growth period of kernel structures, nor pericarp growth rate. By contrast, pollen source determined a trade-off between embryo and endosperm growth rates, which impacted on the embryo/kernel ratio of mature kernels. Modifications to the embryo size were mediated by scutellum cell number. Pollen source also affected (P < 0.01) allocation of embryo chemical compounds. Negative correlations among embryo oil concentration and those of starch (r = 0.98, P < 0.01) and soluble sugars (r = 0.95, P < 0.05) were found. Coincidently, embryos with low oil concentration had an increased (P < 0.05-0.10) scutellum cell area occupied by starch granules and fewer oil bodies. The effects of pollen source on both embryo/kernel ratio and allocation of embryo chemicals seems to be related to the early established sink strength (i.e. sink size and sink activity) of the

Modified NASA-Lewis chemical equilibrium code for MHD applications

NASA Technical Reports Server (NTRS)

Sacks, R. A.; Geyer, H. K.; Grammel, S. J.; Doss, E. D.

1979-01-01

A substantially modified version of the NASA-Lewis Chemical Equilibrium Code was recently developed. The modifications were designed to extend the power and convenience of the Code as a tool for performing combustor analysis for MHD systems studies. The effect of the programming details is described from a user point of view.

Determination of dietary starch in animal feeds and pet food by an enzymatic-colorimetric method: collaborative study.

PubMed

Hall, Mary Beth

2015-01-01

Starch, glycogen, maltooligosaccharides, and other α-1,4- and α-1,6-linked glucose carbohydrates, exclusive of resistant starch, are collectively termed "dietary starch". This nutritionally important fraction is increasingly measured for use in diet formulation for animals as it can have positive or negative effects on animal performance and health by affecting energy supply, glycemic index, and formation of fermentation products by gut microbes. AOAC Method 920.40 that was used for measuring dietary starch in animal feeds was invalidated due to discontinued production of a required enzyme. As a replacement, an enzymatic-colorimetric starch assay developed in 1997 that had advantages in ease of sample handling and accuracy compared to other methods was considered. The assay was further modified to improve utilization of laboratory resources and reduce time required for the assay. The assay is quasi-empirical: glucose is the analyte detected, but its release is determined by run conditions and specification of enzymes. The modified assay was tested in an AOAC collaborative study to evaluate its accuracy and reliability for determination of dietary starch in animal feedstuffs and pet foods. In the assay, samples are incubated in screw cap tubes with thermostable α-amylase in pH 5.0 sodium acetate buffer for 1 h at 100°C with periodic mixing to gelatinize and partially hydrolyze α-glucan. Amyloglucosidase is added, and the reaction mixture is incubated at 50°C for 2 h and mixed once. After subsequent addition of water, mixing, clarification, and dilution as needed, free + enzymatically released glucose are measured. Values from a separate determination of free glucose are subtracted to give values for enzymatically released glucose. Dietary starch equals enzymatically released glucose multiplied by 162/180 (or 0.9) divided by the weight of the as received sample. Fifteen laboratories that represented feed company, regulatory, research, and commercial feed

Enhancement of interfacial adhesion between starch and grafted poly(ε-caprolactone).

PubMed

Ortega-Toro, Rodrigo; Santagata, Gabriella; Gomez d'Ayala, Giovanna; Cerruti, Pierfrancesco; Talens Oliag, Pau; Chiralt Boix, M Amparo; Malinconico, Mario

2016-08-20

The use of a modified poly(ε-caprolactone) (gPCL) to enhance polymer miscibility in films based on thermoplastic starch (S) and poly(ε-caprolactone) is reported. PCL was functionalized by grafting with maleic anyhdride (MA) and/or glycidyl methacrylate (GMA) by reactive blending in a batch mixer. gPCL based materials were analysed in terms of their grafting degree, structural and thermal properties. Blends based on starch and PCL (wt. ratio 80:20) with including gPCL (0, 2.5 and 5wt.%), as a compatibilizer, were obtained by extrusion and compression moulding, and their structural, thermal, mechanical and barrier properties were investigated. Blends containing gPCL evidenced better interfacial adhesion between starch and PCL domains, as deduced from both structural (XRD, FTIR, SEM) and bulk properties (DSC, TGA). Moreover, grafted PCL-based compatibilizers greatly improved functional properties of S-PCL blend films, as pointed out from mechanical performance and higher barrier properties, valuable to meet the food packaging requirements. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fractionation of oats into products enriched with protein, beta-glucan, starch, or other carbohydrates