Cumulative irritation potential of metronidazole gel compared to azelaic acid gel after repeated applications to healthy skin.

PubMed

Ziel, Kristin; Yelverton, Christopher B; Balkrishnan, Rajesh; Feldman, Steven R

2005-01-01

Metronidazole 0.75% gel and azelaic acid 15% gel are commonly used to treat rosacea. Irritation is a common side effect. To assess the cumulative irritation potential of metronidazole 0.75% gel and azelaic acid 15% gel. Metronidazole 0.75% gel, azelaic acid 15% gel, and a white petrolatum negative control were applied under occlusive conditions to the upper back of a total of 33 healthy subjects. There were twelve 24-hour applications (4 times a week) and three 72-hour applications on weekends during a 3-week period. Skin reactions (erythema score +/- other local reaction) were assessed within 15 to 30 minutes of removal of the products. The mean cumulative irritancy index of metronidazole 0.75% gel was significantly lower than that of azelaic acid 15% gel and not significantly higher than the negative control product. There was increasing cumulative irritancy with azelaic acid; no cumulative irritancy was seen for either metronidazole or white petrolatum. Metronidazole 0.75% gel is less irritating in sustained use than azelaic acid 15% gel.

BCL-2 and Bax Expression in Skin Flaps Treated with Finasteride or Azelaic Acid.

PubMed

Ayatollahi, Seyyed Abdulmajid; Ajami, Marjan; Reyhanfard, Hamed; Asadi, Yasin; Nassiri-Kashani, Mansour; Rashighi Firoozabadi, Mehdi; Davoodi, Sayed Hossein; Habibi, Esmaeil; Pazoki-Toroudi, Hamidreza

2012-01-01

Despite all modern surgical techniques, skin flap that is considered as the main method in most reconstructive surgeries puts the skin tissue at danger of necrosis and apoptosis derived from ischemia. Therefore, finding a treatment for decreasing the apoptosis derived from flap ischemia will be useful in clinic. In present study, we evaluated the effect of azelaic acid 20% and finasteride on expression of BCL-2 and bax proteins after the skin flap surgery. For this purpose, 21 rats were entered in three groups including control, azelaic acid 20% and finasteride, all experienced skin flap surgery and then flap tissue was assessed for determining the expression of proteins in 5 slices prepared from each rat that were graded between - to +++ scales. Both azelaic acid and finasteride increased the expression of BCL-2 protein (p < 0.05) and decrease the expression of bax protein (p < 0.05). These results suggested an antiapoptotic role for finasteride and azelaic acid in preserving the flap after the ischemia reperfusion insult.

Solution of Azelaic Acid (20%), Resorcinol (10%) and Phytic Acid (6%) Versus Glycolic Acid (50%) Peeling Agent in the Treatment of Female Patients with Facial Melasma.

PubMed

Faghihi, Gita; Taheri, Azam; Shahmoradi, Zabihollah; Nilforoushzadeh, Mohammad Ali

2017-01-01

Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI). Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid) was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid) was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups ( P > 0.05). However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels ( P < 0.05) and there was the same duration in the beginning of the therapeutic response in both groups. Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel.

Effect of 1,4-cyclohexanediol on percutaneous absorption and penetration of azelaic acid.

PubMed

Li, Nan; Su, Qian; Tan, Fengping; Zhang, Jerry

2010-03-15

The objective of this study is to investigate the effect of 1,4-cyclohexanediol as a retardant on the percutaneous absorption and penetration of azelaic acid. Hairless rat skin was mounted on Franz diffusion cells and treated with topical formulations containing solubilized azelaic acid with and without 1,4-cyclohexanediol. The skin was separated into stratum corneum and the deeper skin layers. The azelaic acid collected in receptor medium and each layer at the end of each time point was extracted and quantified. A significant decrease in flux across the skin suggests a penetration retardation effect of 1,4-cyclohexanediol (42.50 microg/cm(2)/h in the presence of vs. 76.25 microg/cm(2)/h in the absence of) at active loading level of 1.13 mg/cm(2). The penetration retardation effect was also observed at higher active loading level (2.82 mg/cm(2)). Furthermore, presence of 1,4-cyclohexanediol in the topical formulation did not reduce the skin and epidermal retention of azelaic acid, suggesting its potential use in the development of superior topical formation for reducing potential systematic side effect while maintaining therapeutic efficiency. 2009 Elsevier B.V. All rights reserved.

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.

Solution of Azelaic Acid (20%), Resorcinol (10%) and Phytic Acid (6%) Versus Glycolic Acid (50%) Peeling Agent in the Treatment of Female Patients with Facial Melasma

PubMed Central

Faghihi, Gita; Taheri, Azam; Shahmoradi, Zabihollah; Nilforoushzadeh, Mohammad Ali

2017-01-01

Background: Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. Materials and Methods: This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI). Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid) was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Results: Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid) was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups (P > 0.05). However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels (P < 0.05) and there was the same duration in the beginning of the therapeutic response in both groups. Conclusion: Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel. PMID:28299301

BCL-2 and Bax Expression in Skin Flaps Treated with Finasteride or Azelaic Acid

PubMed Central

Ayatollahi, Seyyed Abdulmajid; Ajami, Marjan; Reyhanfard, Hamed; Asadi, Yasin; Nassiri-Kashani, Mansour; Rashighi Firoozabadi, Mehdi; Davoodi, Sayed Hossein; Habibi, Esmaeil; Pazoki-Toroudi, Hamidreza

2012-01-01

Despite all modern surgical techniques, skin flap that is considered as the main method in most reconstructive surgeries puts the skin tissue at danger of necrosis and apoptosis derived from ischemia. Therefore, finding a treatment for decreasing the apoptosis derived from flap ischemia will be useful in clinic. In present study, we evaluated the effect of azelaic acid 20% and finasteride on expression of BCL-2 and bax proteins after the skin flap surgery. For this purpose, 21 rats were entered in three groups including control, azelaic acid 20% and finasteride, all experienced skin flap surgery and then flap tissue was assessed for determining the expression of proteins in 5 slices prepared from each rat that were graded between – to +++ scales. Both azelaic acid and finasteride increased the expression of BCL-2 protein (p < 0.05) and decrease the expression of bax protein (p < 0.05). These results suggested an antiapoptotic role for finasteride and azelaic acid in preserving the flap after the ischemia reperfusion insult. PMID:24250563

Comparison of azelaic acid and anthralin for the therapy of patchy alopecia areata: a pilot study.

PubMed

Sasmaz, Sezai; Arican, Ozer

2005-01-01

Although topical azelaic acid has been previously used for the treatment of alopecia, no controlled trials of azelaic acid for this condition have been conducted to date. The goal of this study was to determine the efficacy, tolerability, and safety of azelaic acid treatment in patients with patchy alopecia areata (AA) in comparison with anthralin (dithranol) treatment. This study included 31 subjects with patchy AA who did not receive any treatment for at least 1 month prior to the study. Demographic and clinical characteristics of these subjects were recorded at baseline. Subjects were randomized to apply either 20% azelaic acid (15 subjects) or 0.5% anthralin (16 subjects) for 12 consecutive weeks. In a subsequent 8-week follow-up period no cream was applied. Two independent investigators performed an efficacy evaluation with clinical examination using a terminal hair regrowth score (RGS) with a scale ranging from 0 (inadequate response) to 2 (complete response) at week 20. Partial response was accepted as score 1. Both groups were well matched for the relevant demographic and clinical indicators affecting treatment response at baseline. All subjects completed the trial. At week 20 the RGS was 1.27 +/- 0.9 in the azelaic acid group versus 1.37 +/- 0.8 in the anthralin group (p > 0.05). A complete response was observed in 53.3% of cases in the azelaic acid group (8 of 15) compared with 56.2% (9 of 16) in the anthralin group (p > 0.05). No serious adverse events were observed in either group during the study. The present pilot study showed that the use of azelaic acid gave similar results to anthralin with regard to hair regrowth, and that it can be an effective topical therapy for patchy AA. More extensive trials are necessary, however, to reach a definitive conclusion.

Real-World Efficacy of Azelaic Acid 15% Gel for the Reduction of Inflammatory Lesions of Rosacea.

PubMed

Wirth, P J; Henderson Berg, M H; Sadick, N

2017-11-01

Approximately 16 million Americans have rosacea, an inflammatory cutaneous disorder with central facial erythema, papules, pustules, telangiectasia, flushing, and swelling being among the more commonly recognized features. Overexpression of cathelicidin peptide LL-37 has been implicated in the pathophysiology of rosacea. Azelaic acid has been found to inhibit the pathologic expression of cathelicidin, as well as the hyperactive protease activity that cleaves cathelicidin into LL-37. Given these findings, a small prospective, open-label, interventional trial was undertaken to assess the effects of azelaic acid 15% gel on inflammatory lesions of papulopustular rosacea in a real-world setting. Use of azelaic acid was associated with a significant reduction in inflammatory lesions, which persisted beyond the active treatment phase. Overall, azelaic acid 15% gel is an appropriate initial topical therapy for the treatment of moderate facial rosacea.

[Azelaic acid 15% gel in the treatment of acne vulgaris. Combined results of two double-blind clinical comparative studies].

PubMed

Gollnick, Harald P M; Graupe, Klaus; Zaumseil, Rolf-Peter

2004-10-01

Topical measures are still the mainstay in the therapy of mild-to-moderate acne vulgaris. Azelaic acid 20% in a cream formulation has been established as an efficacious and safe topical drug for 15 years. A new non-alcoholic hydrogel formulation containing 15% azelaic acid was clinically tested against two standard drugs--5% benzoyl peroxide (BPO) and 1% clindamycin. In two independent, randomized, blinded comparative trials 15% azelaic acid gel was clinically tested against 5% benzoyl peroxide (BPO) gel in 351 patients and against 1% clindamycin gel in 229 patients. The drugs were applied b.i.d. for 4 months. Azelaic acid 15% gel proved to be as effective as BPO and clindamycin with median % reduction of the inflamed lesion (papules and pustules) of 70%, and 71% respectively. The azelaic acid gel was well-tolerated, the side effects (local burning and irritation) were distinctly less than with BPO but more pronounced than with clindamycin. Despite these side effects, the treatment was well-accepted by the majority of patients. Azelaic acid gel is an effective topical monotherapy for mild-to-moderate acne vulgaris; its new gel form is an enrichment of acne therapy.

Implication of azelaic acid in a Greenland Ice Core for oceanic and atmospheric changes in high latitudes

NASA Astrophysics Data System (ADS)

Kawamura, K.; Yokoyama, K.; Fujii, Y.; Watanabe, O.

A Greenland ice core (450 years) has been studied for low molecular weight dicarboxylic acids (C2-C10) using a capillary gas chromatography and mass spectrometer. Their molecular distribution generally showed a predominance of succinic acid (C4) followed by oxalic (C2), malonic (C3), glutaric (C5), adipic (C6), and azelaic (C9) acids. Azelaic acid, that is a specific photochemical reaction product of biogenic unsaturated fatty acids, gave a characteristic historical trend in the ice core; i.e., the concentrations are relatively low during late 16th to 19th century (Little Ice Age) but become very high in late 19th to 20th century (warmer periods) with a large peak in 1940s AD. Lower concentrations of azelaic acid may have been caused by a depressed emission of unsaturated fatty acids from seawater microlayers due to enhanced sea ice coverage during Little Ice Age. Inversely, increased concentrations of azelaic acid in late 19th to 20th century are likely interpreted by an enhanced sea-to-air emission of the precursor unsaturated fatty acids due to a retreat of sea ice and/or by the enhanced production due to a potentially increased oxidizing capability of the atmosphere.

Olfactory receptor Olfr544 responding to azelaic acid regulates glucagon secretion in α-cells of mouse pancreatic islets.

PubMed

Kang, NaNa; Bahk, Young Yil; Lee, NaHye; Jae, YoonGyu; Cho, Yoon Hee; Ku, Cheol Ryong; Byun, Youngjoo; Lee, Eun Jig; Kim, Min-Soo; Koo, JaeHyung

2015-05-08

Olfactory receptors (ORs) are extensively expressed in olfactory as well as non-olfactory tissues. Although many OR transcripts are expressed in non-olfactory tissues, only a few studies demonstrate the functional role of ORs. Here, we verified that mouse pancreatic α-cells express potential OR-mediated downstream effectors. Moreover, high levels of mRNA for the olfactory receptors Olfr543, Olfr544, Olfr545, and Olfr1349 were expressed in α-cells as assessed using RNA-sequencing, microarray, and quantitative real-time RT-PCR analyses. Treatment with dicarboxylic acids (azelaic acid and sebacic acid) increased intracellular Ca(2+) mobilization in pancreatic α-cells. The azelaic acid-induced Ca(2+) response as well as glucagon secretion was concentration- and time-dependent manner. Olfr544 was expressed in α-cells, and the EC50 value of azelaic acid to Olfr544 was 19.97 μM, whereas Olfr545 did not respond to azelaic acid. Our findings demonstrate that Olfr544 responds to azelaic acid to regulate glucagon secretion through Ca(2+) mobilization in α-cells of the mouse pancreatic islets, suggesting that Olfr544 may be an important therapeutic target for metabolic diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

Modification of wheat starch with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures. II. Chemical and physical properties.

PubMed

Ačkar, Durđica; Subarić, Drago; Babić, Jurislav; Miličević, Borislav; Jozinović, Antun

2014-08-01

The aim of this research was to investigate the influence of modification with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures on chemical and physical properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetanhydride and azelaic acid and acetanhydride in 4, 6 and 8% (w/w). Total starch content, resistant starch content, degree of modification, changes in FT-IR spectra, colour, gel texture and freeze-thaw stability were determined. Results showed that resistant starch content increased by both investigated modifications, and degree of modification increased proportionally to amount of reagents used. FT-IR analysis of modified starches showed peak around 1,740 cm(-1), characteristic for carbonyl group of ester. Total colour difference caused by modifications was detectable by trained people. Adhesiveness significantly increased, while freeze-thaw stability decreased by both investigated modifications.

The Efficacy and Safety of Azelaic Acid 15% Foam in the Treatment of Truncal Acne Vulgaris.

PubMed

Hoffman, Lauren K; Del Rosso, James Q; Kircik, Leon H

2017-06-01

INTRODUCTION: Truncal acne is often associated with facial acne, but there are fewer options for an effective topical treatment on the trunk. Given the advent of foam formulations with enhanced percutaneous absorption and convenient application due to easy spreadability on skin, the previously held idea that effective treatment of truncal acne requires oral treatment is challenged. Azelaic acid cream has been previously approved for acne vulgaris, thus azelaic acid foam may be a viable treatment option for truncal acne.

STUDY DESIGN: A single-center, open label pilot study was conducted to investigate the efficacy and safety of azelaic acid 15% foam as a treatment modality for moderate truncal acne. Use for facial acne was also allowed and monitored during the study.

RESULTS: Twice-daily application of azelaic acid 15% foam to affected areas resulted in a 1-grade reduction in truncal investigator global assessment (IGA) scores in nearly all patients (16/18). Eight out of 18 patients (44%) were rated as Clear or Almost Clear in the trunk by the end of the study. There were also improvements in facial IGA scores; 9 of 18 patients (50%) exhibited a 1-grade improvement in IGA scores and 11 of 18 were Clear or Almost Clear by the end of the study. A significant reduction in lesion counts was found throughout the study and the medication was well tolerated.

CONCUSION: Azelaic acid 15% foam was effective in treating moderate truncal acne and facial acne in this pilot study. Given the efficacy and convenience of the foam vehicle, azelaic acid may be considered as a viable option for treatment of acne vulgaris, including on the trunk. Further studies are suggested in a larger population of patients, including adult females with acne.

J Drugs Dermatol. 2017;16(6):534-538.

Steroid-induced periorificial dermatitis in children--clinical features and response to azelaic acid.

PubMed

Jansen, Thomas; Melnik, Bodo C; Schadendorf, Dirk

2010-01-01

Periorificial dermatitis, a common skin disease in young women, has been occasionally reported in children. This study elaborates the clinical features of periorificial dermatitis in children as well as possible pathogenetic factors and the response to 20% azelaic acid cream. A total of 10 children aged 3 to 12 (mean 7.7) years suffering from nongranulomatous periorificial dermatitis for 3 to 7 (mean 4.9) months were evaluated, and dermatologic examination was carried out. Pretreatment was documented. Skin prick tests with a panel of six common inhalative allergens and patch tests with the European Standard Series were performed. An association between atopy and periorificial dermatitis was evaluated, and patients were screened for skin colonization by fungi, bacteria, and Demodex mites. They were treated with 20% azelaic acid cream, which was topically applied twice daily on all affected areas, until complete resolution was achieved. Treatment period was followed by an individual observation period. Periorificial dermatitis had developed in typical distribution and morphology. In all patients, low- to high-potency topical corticosteroids had been used on the face prior to manifestation. Atopy was found in half of the patients. Allergological, bacteriological, and mycological examinations did not reveal pathologic results. Demodex mites could not be demonstrated by skin surface biopsy. Treatment with 20% azelaic acid cream led to complete resolution of skin lesions after 4 to 8 (mean 5.4) weeks in all patients. Transient exacerbation of skin condition with a peak between the 2nd and 6th day of treatment could be observed in three patients. Side effects of 20% azelaic acid cream were registered in six patients and were predominantly present in the first 2 weeks of treatment. Side effects were minimal and became rarer with ongoing treatment. No recurrences were seen within a follow-up period of 2 to 8 (mean 4.4) months. Treatment with 20% azelaic acid cream could

A clinical overview of azelaic acid.

PubMed

Elewski, Boni; Thiboutot, Diane

2006-02-01

Azelaic acid (AzA) initially was released in a 20% cream formulation, which has been shown to be effective in the treatment of mild to moderate rosacea. Recently, a 15% gel formulation was developed that vastly improved the delivery of AzA and has been proven by multiple studies to be effective in the treatment of rosacea. We present studies that examine both of these formulations, first in comparison with their vehicles and then in contrast with other well-accepted topical treatments of rosacea, such as metronidazole cream and gel.

Cumulative irritation potential among metronidazole gel 1%, metronidazole gel 0.75%, and azelaic acid gel 15%.

PubMed

Colón, Luz E; Johnson, Lori A; Gottschalk, Ronald W

2007-04-01

Topical therapy for rosacea aims to reduce inflammatory lesions and decrease erythema but can carry side effects such as stinging, pruritus, and burning. Metronidazole and azelaic acid gel 15% are U.S. Food and Drug Administration-approved for the treatment of rosacea. The current study was conducted to assess the cumulative irritation potential of 2 formulations of metronidazole 0.75% gel and 1% gel--and azelaic acid gel 15% over 21 days (N=36). Results of this study demonstrated a significantly greater poten tial for irritation from azelaic acid compared with metronidazole gel 0.75% (P < .0001), which had significantly greater potential for irritation compared with metronidazole gel 1% (P = .0054). Metronidazole gel 1% had a similar profile to white petrolatum.

Retinoids and azelaic acid to treat acne and hyperpigmentation in skin of color.

PubMed

Woolery-Lloyd, Heather C; Keri, Jonette; Doig, Stefan

2013-04-01

In this review, we examine published data reporting the efficacy of pharmaceutical agents to treat associated postinflammatory hyperpigmentation commonly seen in skin of color. Retinoids and azelaic acid have been widely used to treat acne. Now there are increasing data describing their use in skin of color for the treatment of both acne and the subsequent postinflammatory hyperpigmentation. Historically, some dermatologists have been hesitant to use retinoids in skin of color because of perceived hypersensitivity in this patient population. However, recent data support the use of retinoids and azelaic acid in skin of color as both safe and beneficial.

Azelaic Acid Topical Formulations: Differentiation of 15% Gel and 15% Foam.

PubMed

Del Rosso, James Q

2017-03-01

In this article, the author reviews topical formulations of azelaic acid used to treat papulopustular rosacea. Emphasis is placed on differences in vehicle technology and potential clinical impact of the possibility for neurosensory cutaneous tolerability reactions.

Application of HPLC with ELSD Detection for the Assessment of Azelaic Acid Impurities in Liposomal Formulation

PubMed Central

Han, Stanislaw; Karlowicz-Bodalska, Katarzyna; Ozimek, Lukasz

2013-01-01

In the course of research and development of a new pharmaceutical formulation of azelaic acid in the liposomal form, we developed a rapid and accurate method for the detection of impurities using high-performance liquid chromatography. A chromatographic column from Merck (Purospher Star RP C18, 250–4 mm (5 μm) was used in the assay, and the mobile phase gradient consisted of three phases: A—methanol : water (5 : 95) + 1.5% (v/v) acetic acid; B—water : methanol (5 : 95) + 1.5% (v/v) acetic acid; and C—chloroform. Detection of the impurities and the active substance was performed by an evaporative light-scattering detector. The method was validated for selectivity, system precision, method precision, limit of detection, and response rates. The proposed method can be used to detect impurities in the liposomal formulation of azelaic acid. The method enables separation of azelaic acid from the identified and unidentified impurities and from the excipients used in the drug form. PMID:24228008

Application of HPLC with ELSD detection for the assessment of azelaic acid impurities in liposomal formulation.

PubMed

Han, Stanislaw; Karlowicz-Bodalska, Katarzyna; Szura, Dorota; Ozimek, Lukasz; Musial, Witold

2013-01-01

In the course of research and development of a new pharmaceutical formulation of azelaic acid in the liposomal form, we developed a rapid and accurate method for the detection of impurities using high-performance liquid chromatography. A chromatographic column from Merck (Purospher Star RP C18, 250-4 mm (5 μm) was used in the assay, and the mobile phase gradient consisted of three phases: A--methanol : water (5 : 95) + 1.5% (v/v) acetic acid; B--water : methanol (5 : 95) + 1.5% (v/v) acetic acid; and C--chloroform. Detection of the impurities and the active substance was performed by an evaporative light-scattering detector. The method was validated for selectivity, system precision, method precision, limit of detection, and response rates. The proposed method can be used to detect impurities in the liposomal formulation of azelaic acid. The method enables separation of azelaic acid from the identified and unidentified impurities and from the excipients used in the drug form.

Efficacy of 15% azelaic acid in psoriasis vulgaris: a randomized, controlled clinical trial.

PubMed

Iraji, Fariba; Faghihi, Gita; Siadat, Amir Hossein; Enshaieh, Shahla; Shahmoradi, Zabihlah; Joia, Abolfazl; Soleimani, Fatemeh

2010-08-01

Psoriasis is a common disorder affecting 1-3 percent of the general global population. Many therapeutic modalities have been suggested for treatment of this condition, but still there is no definite treatment for this disease. The objective in this study was to evaluate the efficacy of topical azelaic acid gel versus placebo in the treatment of psoriasis vulgaris. This study was a single-blinded randomized clinical trial. Overall, 31 patients were selected and the left or right sided lesions of the patients were randomized to receive either 15% azelaic acid or gel twice daily for a one-month period. Two symmetrical lesions with almost similar severity in every patient were selected and considered as index lesions to evaluate lesion response to treatment. The severity of erythema, scaling, hyperkeratosis and pruritus of the index lesions were scored in range of 0-3 for each lesion by the investigator at the baseline and follow up visits. The percent of involvement of each side of body was also measured using rule of nines. The collected data were analyzed using statistical tests including Mann-Whitney and ANOVA tests. There was no significant difference between the two groups before treatment (P > 0.05). After treatment, however, except pruritus, there was significant difference between the two groups (P < 0.05). There was no significant difference regarding total psoriasis score between the two groups before treatment (P > 0.05). After treatment, however, there was significant difference between the two groups (P < 0.05) in favor of more efficacy for azelaic acid. There was no significant difference regarding percent of body involvement between the two groups before treatment (P > 0.05). After treatment, however, there was a significant difference between the two groups (P < 0.05) in favor of more efficacy on the part of azelaic acid gel. The results of our study showed that 15% azelaic acid gel was effective in reduction of purities, scaling and hyperkeratosis of

Noxious sensory perceptions in patients with mild to moderate rosacea treated with azelaic acid 15% gel.

PubMed

Draelos, Zoe Diana

2004-10-01

Patients with rosacea form a unique subset of the sensitive skin population because of the barrier defects inherent in this condition and the increased propensity for burning/stinging from topical products. This propensity for burning/ stinging when medications, skin care products, or cosmetics are applied to the facial skin has been frequently documented but never quantified. The objective of this 2-week study was to determine the prevalence of heightened neurosensory perceptions of burning/stinging in a random population of 40 women with mild to moderate rosacea defined as 15 or fewer inflammatory papules or pustules. Also evaluated was the effect of azelaic acid 15% gel on barrier function and facial stinging utilizing transepidermal water loss (TEWL), corneometry, and lactic acid facial sting tests as noninvasive measurement criteria. At baseline, the incidence of lactic acid stinging among these rosacea subjects was 62.5%, which is substantially higher than observed in the general population. Two weeks after application of azelaic acid 15% gel, no evidence of barrier damage was noted on TEWL or corneometry tests. Moreover, there was no statistical relationship between lactic acid stinging and a stinging response that is occasionally reported with exposure to azelaic acid 15% gel.

Azelaic Acid Topical Formulations: Differentiation of 15% Gel and 15% Foam

PubMed Central

2017-01-01

In this article, the author reviews topical formulations of azelaic acid used to treat papulopustular rosacea. Emphasis is placed on differences in vehicle technology and potential clinical impact of the possibility for neurosensory cutaneous tolerability reactions. PMID:28360967

Efficacy and safety of once-daily metronidazole 1% gel compared with twice-daily azelaic acid 15% gel in the treatment of rosacea.

PubMed

Wolf, John E; Kerrouche, Nabil; Arsonnaud, Stephanie

2006-04-01

Rosacea is an inflammatory dermatologic disorder characterized by the presence of facial erythema, visible blood vessels, papules, and pustules. The National Rosacea Society has established a classification system that identifies 4 distinct rosacea subtypes based on clinical presentation: erythematotelangiectatic, papulopustular, phymatous, and ocular. The goal of topical therapy for rosacea is to reduce inflammatory lesion counts; decrease intensity of erythema; and reduce symptoms such as stinging, burning, and pruritus. Metronidazole and azelaic acid are thought to reduce the inflammation associated with rosacea by inhibiting the production of reactive oxygen species produced by neutrophils. Both metronidazole 1% gel and azelaic acid 15% gel recently have been approved for the treatment of rosacea. The current study was conducted to compare the once-daily application of metronidazole 1% gel with twice-daily applications of azelaic acid 15% gel for the treatment of patients with moderate rosacea (N=160). Both treatments showed similar reductions in inflammatory lesion counts (77% for metronidazole 1% gel and 80% for azelaic acid 15% gel) and high success rates in both global severity (53.7% vs 56.4% for metronidazole 1% gel and azelaic acid 15% gel, respectively) and erythema (42.7% vs 42.3% for metronidazole 1% gel and azelaic acid 15% gel, respectively). On average, the efficacy (including reduction in erythema) of the once-daily application of metronidazole 1% gel and twice-daily applications of azelaic acid 15% gel were similar.

Comparative study of therapeutic effects of 20% azelaic acid and hydroquinone 4% cream in the treatment of melasma.

PubMed

Farshi, Susan

2011-12-01

  Melasma is an irregular brown or grayish-brown symmetric facial hypermelanosis, often affecting women, especially those living in areas with intense ultraviolet radiation.   Comparison of therapeutic effects of 20% azelaic acid and 4% hydroquinone cream in the treatment of melasma.   Twenty-nine women with melasma were recruited. Fifteen patients were treated with 4% hydroquinone cream and 14 patients were treated with azelaic acid cream for 2 months. The cream was applied twice daily. A broad-spectrum sunscreen was used concomitantly by both groups. The Melasma Area Severity Index (MASI) scores were determined prior to treatment and at each follow-up.   The mean MASI score before treatment was 7.2 ± 3.2 in the hydroquinone group and 7.6 ± 3.5 in the azelaic acid group, with no significant difference between them (t-test, CI 95% = -2.9 to 2.2). One month after treatment, the mean MASI score reached 6.7 ± 3.4 with hydroquinone and 6.3 ± 3.4 with azelaic acid with no significant difference between them (t-test, CI 95% = -2.2 to 3). After 2 months' treatment, the MASI score was 6.2 ± 3.6 with hydroquinone and 3.8 ± 2.8 with azelaic acid, a significant statistical difference (t-test, CI 95% = 0.03-4.9).   In conclusion, this study suggests that 20% azelaic acid cream applied twice daily may be more effective than hydroquinone 4% in reducing mild melasma. However, because this was an open trial, it is suggested that further studies involving large groups of patients be conducted to achieve a more conclusive result. © 2011 Wiley Periodicals, Inc.

A comparison of 15% azelaic acid gel and 0.75% metronidazole gel in the topical treatment of papulopustular rosacea: results of a randomized trial.

PubMed

Elewski, Boni E; Fleischer, Alan B; Pariser, David M

2003-11-01

To compare the efficacy and safety of a novel formulation of 15% azelaic acid gel (Finacea; Berlex Laboratories, Inc, Montville, NJ) with 0.75% metronidazole gel (MetroGel; Galderma Laboratories LP, Fort Worth, Tex) as topical therapy for moderate, papulopustular facial rosacea. Multicenter, double-blind, randomized, parallel-group study. Thirteen US centers. A total of 251 patients with papulopustular rosacea with persistent erythema and telangiectasia. Patients were randomized to receive azelaic acid gel or metronidazole gel twice daily for 15 weeks. Nominal and percent change in inflammatory lesion count, change in erythema and telangiectasia severity ratings, investigator's global assessment of rosacea, and investigator's and patient's overall improvement ratings. Azelaic acid gel was superior to metronidazole gel in reduction of mean nominal lesion count (-12.9 vs -10.7, respectively) (P =.003) and mean percent decrease in inflammatory lesions (-72.7% vs -55.8%, respectively) (P<.001). With respect to erythema severity, 56% of azelaic acid gel-treated patients were rated improved vs 42% of metronidazole gel-treated patients (P =.02). The effectiveness of metronidazole gel on these variables seemed to plateau after week 8, whereas azelaic acid gel demonstrated progressive improvement through week 15. Neither treatment had a clinically appreciable effect on telangiectasia. Both the investigator's global assessment (P =.02) and overall assessment of improvement (P =.005) showed a significant therapeutic advantage for azelaic acid gel. Azelaic acid gel also scored higher on the patient's overall assessment of efficacy. Both treatments were rated as having high cosmetic acceptability. No serious or systemic treatment-related adverse events were reported in either group. Use of 15% azelaic acid gel twice daily for 15 weeks demonstrated significant superiority over using 0.75% metronidazole gel in improving principal signs of rosacea (inflammatory lesions and

Rapid radiosynthesis of [11C] and [14C]azelaic, suberic, and sebacic acids for in vivo mechanistic studies of systemic acquired resistance in plants

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

Best M.; Fowler J.; Best, M.

2011-11-25

A recent report that the aliphatic dicarboxylic acid, azelaic acid (1,9-nonanedioic acid) but not related acids, suberic acid (1,8-octanedioic acid) or sebacic (1,10-decanedioic acid) acid induces systemic acquired resistance to invading pathogens in plants stimulated the development of a rapid method for labeling these dicarboxylic acids with {sup 11}C and {sup 14}C for in vivo mechanistic studies in whole plants. {sup 11}C-labeling was performed by reaction of ammonium [{sup 11}C]cyanide with the corresponding bromonitrile precursor followed by hydrolysis with aqueous sodium hydroxide solution. Total synthesis time was 60 min. Median decay-corrected radiochemical yield for [{sup 11}C]azelaic acid was 40% relativemore » to trapped [{sup 11}C]cyanide, and specific activity was 15 GBq/{micro}mol. Yields for [{sup 11}C]suberic and sebacic acids were similar. The {sup 14}C-labeled version of azelaic acid was prepared from potassium [{sup 14}C]cyanide in 45% overall radiochemical yield. Radiolabeling procedures were verified using {sup 13}C-labeling coupled with {sup 13}C-NMR and liquid chromatography-mass spectrometry analysis. The {sup 11}C and {sup 14}C-labeled azelaic acid and related dicarboxylic acids are expected to be of value in understanding the mode-of-action, transport, and fate of this putative signaling molecule in plants.« less

Azelaic acid: Properties and mode of action.

PubMed

Sieber, M A; Hegel, J K E

2014-01-01

Acne is a common skin disorder that can be problematic for adults as well as for adolescents. It has several key pathophysiological features such as follicular hyperkeratosis, elevated Propionibacterium acnes proliferation, and reactive inflammation, all of which should be targeted for an optimal outcome. Azelaic acid (AzA) has profound anti-inflammatory, antioxidative effects, and is bactericidal against a range of Gram-negative and Gram-positive microorganisms as well, including antibiotic-resistant bacterial strains. In addition, AzA's antikeratinizing effects are inhibitory toward comedones. AzA is effective overall in targeting multiple causes of acne and has been proven to be well tolerated in numerous clinical trials. © 2013 S. Karger AG, Basel.

Phototoxic effects of topical azelaic acid, benzoyl peroxide and adapalene were not detected when applied immediately before UVB to normal skin.

PubMed

Cetiner, Salih; Ilknur, Turna; Ozkan, Sebnem

2004-01-01

The enhancing effects on UVB erythema of topical agents applied on sun exposed areas are important due to their increased sunburn risk. Since the lesions in acne vulgaris are seen primarily on the face, the effects of topical agents used in acne treatment on the erythemogenicity of UVB is important. The aim of the present study was to examine whether azelaic acid cream, benzoyl peroxide gel, adapalene gel have the enhancing effects on UVB erythema which are widely used in the topical treatment of acne vulgaris. The minimal erythema dose (MED) was determined with phototest in 30 volunteers and the test was repeated with thin (0.1 cc/25 cm(2)) and thick (0.3 cc/25 cm(2)) azelaic acid cream, benzoyl peroxide gel, adapalene gel. The effects of each agent on MED was determined after 24 hours. MEDs of UVB were unaffected by azelaic acid cream, benzoyl peroxide gel and adapalene gel when applied immediately before irradiation. According to our results azelaic acid, benzoyl peroxide and adapalene do not seem to have enhancing effects on UVB erythema and thus increased sunburn risk.

The rationale for advancing the formulation of azelaic acid vehicles.

PubMed

Draelos, Zoe Diana

2006-02-01

When first approved in December 2002, 15% azelaic acid (AzA) gel represented a significant advance over the available 20% AzA cream. Although a smaller amount of AzA was present in the new formulation, the gel medium provided a highly effective system for delivering the active ingredient, thus providing more effective treatment. This article explores the nature of these 2 vehicles and highlights the importance of the formulation in which dermatologic drugs are delivered.

Cellulase applied to the leaves of sweet pepper (Capsicum annuum L. var. grossum) upregulates the production of salicylic and azelaic acids.

PubMed

Sato, Chizuru; Oka, Norikuni; Nabeta, Kensuke; Matsuura, Hideyuki

2011-01-01

Treating the leaves of sweet pepper (Capsicum annuum L. var. grossum) with an aqueous solution of cellulase resulted in a four-fold increase in the salicylic acid level compared to a control plant. The level of endogenous azelaic acid was also elevated by the cellulase treatment. Azelaic acid has recently been reported to act as a mobile "priming" agent to arm plants against pathogenic attack. Our results are consistent with this and that the cellulase treatment enhanced the ability of sweet pepper to withstand viral attack.

Update on the management of rosacea: a status report on the current role and new horizons with topical azelaic acid.

PubMed

Del Rosso, James Q; Kircik, Leon H

2014-12-01

Azelaic acid (AzA) 15% gel has been available in the United States for slightly over a decade, approved for treatment of the inflammatory lesions (papules and pustules) of rosacea. Efficacy and safety have been established in multiple studies both as monotherapy and in combination with oral doxycycline. Azelaic acid 15% gel has been shown not to induce epidermal permeability barrier impairment, and proper skin care reduces the likelihood of neurosensory adverse effects of stinging and burning that can affect a subset of patients with rosacea. Azelaic acid 15% gel appears to produce a quicker onset of clinical effect than metronidazole in some patients when either agent is used in combination with subantimicrobial dose doxycycline; however, both topical agents are effective when used in this combination approach for papulopustular rosacea (PPR). Although more information is needed on the modes of action of AzA in the treatment of rosacea, downregulation of the cathelicidin pathway appears to be one operative mode of action based on in vitro and in vivo studies, including data from patients treated with AzA 15% gel for PPR. Azelaic acid 15% foam is currently in the latter stages of development for PPR, with pivotal studies demonstrating efficacy and favorable tolerability, including a very low incidence of stinging, burning, and itching even without the use of designated skin care products.

The Development of Analytical Method for the Determination of Azelaic Acid Content in Cosmetic Cream Products

NASA Astrophysics Data System (ADS)

Lusianti, E.; Wibowo, R.; Hudiyono, S.

2018-01-01

Azelaic acid is one of the substances that has anti-acne and skin lightening effects which is often added to cosmetics. In the acne treatment, the azelaic acid is generally used with a concentration of 20% in cream formulation and 15% in gel. The use at concentrations below 10% is not recommended because it does not work effectively. While the use of above 10% is categorized as a medical treatment. In Indonesia, the Head of the National Agency of Drug and Food Control (BPOM) has issued Regulation No. 18 of 2015 on the Technical Requirements of Cosmetics Ingredients Annex V stating that the azelaic acid is banned in cosmetics. However, until this research began the BPOM has not had a valid method to identify it in cosmetics. Consequently, surveillance of such ingredient in products is hard to do. In this research, the fatty acid standard analysis method of AOAC International was modified and validated to be used in the laboratory. The method of analysis involves heating the cream preparations dissolved with methanol and then added BF3-methanol catalyst, followed by extraction and analysis using GCMS. The validation of method shows that the calibration curve is linear with correlative value of 0.9997. The method is fairly sensitive with 0.02% detection limit, and fairly precision with relative standard deviation (RSD) of between 0.626-0.961% and fairly accurate which the recovery percentage is 99.85% at range 98.27-100.72%. In sum the results demonstrate that the method can be used as a routine analysis method for laboratory testing.

Azelaic acid in the treatment of acne in adult females: case reports.

PubMed

Vargas-Diez, E; Hofmann, M A; Bravo, B; Malgazhdarova, G; Katkhanova, O A; Yutskovskaya, Y

2014-01-01

Acne, one of the most common skin problems in dermatological practice, is a condition that affects not only adolescents but also adults. While approximately 80% of cases occurring in adulthood are persistent from teenage years, around 20% are described as 'late-onset' disease, appearing for the first time in adulthood. The disease can be triggered by hormonal changes (including a change from one contraceptive to another), or it can be induced by certain nonhormonal medications, emotional stress, and various underlying diseases such as polycystic ovary syndrome. In many cases acne becomes a chronic skin condition with undulating activity, including improvement and relapse phases, and is often experienced as a major psychological burden. It is, therefore, even more important to provide an effective as well as a safe and tolerable treatment. The spectrum of topical acne treatments has expanded substantially in recent years and various topical medications are available, ranging from azelaic acid, antibiotics, retinoids and benzoyl peroxide to several fixed combinations of these active compounds. The following case collection illustrates how 15% azelaic acid gel, as a well-established monotherapy, can be successfully employed to treat mild-to-moderate forms of adult female acne. © 2013 S. Karger AG, Basel.

Potential for mcl-PHA production from nonanoic and azelaic acids.

PubMed

Gillis, James; Ko, Kenton; Ramsay, Juliana A; Ramsay, Bruce A

2018-01-01

Greater than 65% of canola and high-oleic soy oil fatty acids is oleic acid, which is readily converted to nonanoic (NA) and azelaic (AzA) acids by ozonolysis. NA is an excellent substrate for medium-chain-length polyhydroxyalkanoate (mcl-PHA) production but AzA has few uses. Pseudomonas citronellolis DSM 50332 and Pseudomonas fluorescens ATCC 17400, both able to produce mcl-PHA from fatty acids and to grow on AzA as the sole source of carbon and energy, were assessed for the accumulation of mcl-PHA from AzA and NA. In N-limited shake flasks using NA, P. citronellolis produced 32% of its dry biomass as mcl-PHA containing 78% 3-hydroxynonanoate with 22% 3-hydroxyheptanoate. Pseudomonas fluorescens produced only 2% PHA. N-limited P. citronellolis on AzA produced 20% dry weight PHA containing 75% 3-hydroxydecanoate and 25% 3-hydroxyoctanoate, indicative of de novo synthesis. Although selective pressure, including β-oxidation inhibition, under well-controlled (chemostat) conditions was applied to P. citronellolis, no side-chain carboxyl groups were detected. It was concluded that one or more of FabG and PhaJ or the PHA synthase cannot catalyze reactions involving ω-carboxy substrates. However, a process based on oleic acid could be established if Pseudomonas putida was engineered to grow on AzA.

A Comparison of Low-Fluence 1064-nm Q-Switched Nd: YAG Laser with Topical 20% Azelaic Acid Cream and their Combination in Melasma in Indian Patients.

PubMed

Bansal, Charu; Naik, Hira; Kar, Hemanta K; Chauhan, Amrita

2012-10-01

Melasma is an acquired symmetric hypermelanosis characterised by irregular light to gray-brown macules on sun-exposed skin with a predilection for the cheeks, forehead, upper lip, nose and chin. The management of melasma is challenging and requires meticulous use of available therapeutic options. To compare the therapeutic efficacy of low-fluence Q-switched Nd: YAG laser (QSNYL) with topical 20% azelaic acid cream and their combination in melasma in three study groups of 20 patients each. Sixty Indian patients diagnosed as melasma were included. These patients were randomly divided in three groups (group A = 20 patients of melasma treated with low-fluence QSNYL at weekly intervals, group B = 20 patients of melasma treated with twice daily application of 20% azelaic acid cream and group C = 20 patients of melasma treated with combination of both). Study period was of 12 weeks each. Response to treatment was assessed using melasma area and severity index score. The statistical analysis was done using Chi-square test, paired and unpaired student t-test. Significant improvement was recorded in all the three groups. The improvement was statistically highly significant in Group C as compared to group A (P < 0.001) and group B (P < 0.001). This study shows the efficacy of low-fluence QSNYL, topical 20% azelaic acid cream and their combination in melasma. The combination of low-fluence QSNYL and topical 20% azelaic acid cream yields better results as compared to low-fluence QSNYL and azelaic acid alone.

Anti-Atherosclerotic Actions of Azelaic acid, an End Product of Linoleic Acid Peroxidation, in Mice

PubMed Central

Litvinov, Dmitry; Selvarajan, Krithika; Garelnabi, Mahdi; Brophy, Larissa; Parthasarathy, Sampath

2009-01-01

Background Atherosclerosis is a chronic inflammatory disease associated with the accumulation of oxidized lipids in arterial lesions. Recently we studied the degradation of peroxidized linoleic acid and suggested that oxidation is an essential process that results in the generation of terminal products, namely mono- and dicarboxylic acids that may lack the pro-atherogenic effects of peroxidized lipids. In continuation of that study, we tested the effects of azelaic acid (AzA), one of the end products of linoleic acid peroxidation, on the development of atherosclerosis using low density lipoprotein receptor knockout (LDLr−/−) mice. Methods and results LDLr−/− mice were fed with a high fat and high cholesterol Western diet (WD group). Another group of animals were fed the same diet with AzA supplementation (WD+AzA group). After four months of feeding, mice were sacrificed and atherosclerotic lesions were measured. The results showed that the average lesion area in WD+AzA group was 38% (p<0.001) less as compared to WD group. The athero-protective effect of AzA was not related to changes in plasma lipid content. AzA supplementation decreased the level of CD68 macrophage marker by 34% (p<0.05). Conclusions The finding that AzA exhibits an anti-atherogenic effect suggests that oxidation of lipid peroxidation-derived aldehydes into carboxylic acids could be an important step in the body’s defense against oxidative damage. PMID:19880116

Anti-atherosclerotic actions of azelaic acid, an end product of linoleic acid peroxidation, in mice.

PubMed

Litvinov, Dmitry; Selvarajan, Krithika; Garelnabi, Mahdi; Brophy, Larissa; Parthasarathy, Sampath

2010-04-01

Atherosclerosis is a chronic inflammatory disease associated with the accumulation of oxidized lipids in arterial lesions. Recently we studied the degradation of peroxidized linoleic acid and suggested that oxidation is an essential process that results in the generation of terminal products, namely mono- and dicarboxylic acids that may lack the pro-atherogenic effects of peroxidized lipids. In continuation of that study, we tested the effects of azelaic acid (AzA), one of the end products of linoleic acid peroxidation, on the development of atherosclerosis using low density lipoprotein receptor knockout (LDLr(-/-)) mice. LDLr(-/-) mice were fed with a high fat and high cholesterol Western diet (WD group). Another group of animals were fed the same diet with AzA supplementation (WD+AzA group). After 4 months of feeding, mice were sacrificed and atherosclerotic lesions were measured. The results showed that the average lesion area in WD+AzA group was 38% (p<0.001) less as compared to WD group. The athero-protective effect of AzA was not related to changes in plasma lipid content. AzA supplementation decreased the level of CD68 macrophage marker by 34% (p<0.05). The finding that AzA exhibits an anti-atherogenic effect suggests that oxidation of lipid peroxidation-derived aldehydes into carboxylic acids could be an important step in the body's defense against oxidative damage. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

A Comparison of Low-Fluence 1064-nm Q-Switched Nd: YAG Laser with Topical 20% Azelaic Acid Cream and their Combination in Melasma in Indian Patients

PubMed Central

Bansal, Charu; Naik, Hira; Kar, Hemanta K; Chauhan, Amrita

2012-01-01

Background: Melasma is an acquired symmetric hypermelanosis characterised by irregular light to gray-brown macules on sun-exposed skin with a predilection for the cheeks, forehead, upper lip, nose and chin. The management of melasma is challenging and requires meticulous use of available therapeutic options. Aims: To compare the therapeutic efficacy of low-fluence Q-switched Nd: YAG laser (QSNYL) with topical 20% azelaic acid cream and their combination in melasma in three study groups of 20 patients each. Materials and Methods: Sixty Indian patients diagnosed as melasma were included. These patients were randomly divided in three groups (group A = 20 patients of melasma treated with low-fluence QSNYL at weekly intervals, group B = 20 patients of melasma treated with twice daily application of 20% azelaic acid cream and group C = 20 patients of melasma treated with combination of both). Study period was of 12 weeks each. Response to treatment was assessed using melasma area and severity index score. Statistical Analysis: The statistical analysis was done using Chi-square test, paired and unpaired student t-test. Results: Significant improvement was recorded in all the three groups. The improvement was statistically highly significant in Group C as compared to group A (P < 0.001) and group B (P < 0.001). Conclusions: This study shows the efficacy of low-fluence QSNYL, topical 20% azelaic acid cream and their combination in melasma. The combination of low-fluence QSNYL and topical 20% azelaic acid cream yields better results as compared to low-fluence QSNYL and azelaic acid alone. PMID:23378709

Azelaic acid gel 15%: clinical versatility in the treatment of rosacea.

PubMed

Del Rosso, James Q; Baum, Eric W; Draelos, Zoe Diana; Elewski, Boni E; Fleischer, Alan B; Kakita, Lenore S; Thiboutot, Diane

2006-11-01

There are numerous proposed but contested components involved in the pathophysiology of rosacea, including inflammatory mediators, reactive oxygen species (ROS) released by neutrophils, and microbial components. Ideal comprehensive rosacea management should address these components. Azelaic acid (AzA), a naturally occurring substance, has many proposed mechanisms of action--antimicrobial, anti-inflammatory/antioxidant, and keratinolytic--that address the proposed components of rosacea pathophysiology and has demonstrated efficacy in subtype 2 rosacea. In a roundtable discussion, information leaders discussed the pathophysiology of rosacea and other issues of importance to successful rosacea management, such as skin care regimens, quality of life (QOL), and compliance.

Untargeted metabolomics analysis reveals dynamic changes in azelaic acid- and salicylic acid derivatives in LPS-treated Nicotiana tabacum cells.

PubMed

Mhlongo, M I; Tugizimana, F; Piater, L A; Steenkamp, P A; Madala, N E; Dubery, I A

2017-01-22

To counteract biotic stress factors, plants employ multilayered defense mechanisms responsive to pathogen-derived elicitor molecules, and regulated by different phytohormones and signaling molecules. Here, lipopolysaccharide (LPS), a microbe-associated molecular pattern (MAMP) molecule, was used to induce defense responses in Nicotiana tabacum cell suspensions. Intracellular metabolites were extracted with methanol and analyzed using a liquid chromatography-mass spectrometry (UHPLC-qTOF-MS/MS) platform. The generated data were processed and examined with multivariate and univariate statistical tools. The results show time-dependent dynamic changes and accumulation of glycosylated signaling molecules, specifically those of azelaic acid, salicylic acid and methyl-salicylate as contributors to the altered metabolomic state in LPS-treated cells. Copyright © 2016 Elsevier Inc. All rights reserved.

[Acne therapy with topical benzoyl peroxide, antibiotics and azelaic acid].

PubMed

Worret, Wolf-Ingo; Fluhr, Joachim W

2006-04-01

effects in a discotheque. There are two reports of topical clindamycin causing pseudomembranous colitis after long-term and widespread usage. Azelaic acid has a predominant antibacterial action, although it is not considered as an antibiotic in the classical sense. Furthermore, it possesses a modest comedolytic effect. Burning upon application is common. Since azelaic acid is naturally present, systemic side effects are not likely to occur, making it safe for acne treatment during pregnancy and lactation.

Enhancing the Bioconversion of Azelaic Acid to Its Derivatives by Response Surface Methodology.

PubMed

Khairudin, Nurshafira; Basri, Mahiran; Fard Masoumi, Hamid Reza; Samson, Shazwani; Ashari, Siti Efliza

2018-02-13

Azelaic acid (AzA) and its derivatives have been known to be effective in the treatment of acne and various cutaneous hyperpigmentary disorders. The esterification of azelaic acid with lauryl alcohol (LA) to produce dilaurylazelate using immobilized lipase B from Candida antarctica (Novozym 435) is reported. Response surface methodology was selected to optimize the reaction conditions. A well-fitting quadratic polynomial regression model for the acid conversion was established with regards to several parameters, including reaction time and temperature, enzyme amount, and substrate molar ratios. The regression equation obtained by the central composite design of RSM predicted that the optimal reaction conditions included a reaction time of 360 min, 0.14 g of enzyme, a reaction temperature of 46 °C, and a molar ratio of substrates of 1:4.1. The results from the model were in good agreement with the experimental data and were within the experimental range (R² of 0.9732).The inhibition zone can be seen at dilaurylazelate ester with diameter 9.0±0.1 mm activities against Staphylococcus epidermidis S273. The normal fibroblasts cell line (3T3) was used to assess the cytotoxicity activity of AzA and AzA derivative, which is dilaurylazelate ester. The comparison of the IC 50 (50% inhibition of cell viability) value for AzA and AzA derivative was demonstrated. The IC 50 value for AzA was 85.28 μg/mL, whereas the IC 50 value for AzA derivative was more than 100 μg/mL. The 3T3 cell was still able to survive without any sign of toxicity from the AzA derivative; thus, it was proven to be non-toxic in this MTT assay when compared with AzA.

Azelaic Acid Exerts Antileukemic Activity in Acute Myeloid Leukemia

PubMed Central

Pan, Yunbao; Liu, Dong; Wei, Yongchang; Su, Dan; Lu, Chenyang; Hu, Yanchao; Zhou, Fuling

2017-01-01

Acute myeloid leukemia (AML) is an acute leukemia common in most adults; its prevalence intensifies with age. The overall survival of AML is very poor because of therapeutic resistance. Azelaic acid (AZA) is non-toxic, non-teratogenic, and non-mutagenic and its antitumor effect on various tumor cells is well established; Nonetheless, its therapeutic effects in AML cells are largely unknown. In this study, it was shown that AZA significantly inhibits the cell viability and induces apoptosis in AML cells in a dose-dependent manner. Additionally, AZA suppressed the expression of phosphorylated Akt, Jab1 and Trx, and this suppression was enhanced by treatment with Jab1 siRNA. Furthermore, AZA sensitized AML cells to Ara-c chemotherapy. The suppressive effect of AZA on tumor growth was examined in vivo by subcutaneously inoculated AML cells in a tumor model using nude mice. These findings indicate that AZA is useful as an effective ingredient in antineoplastic activity. PMID:28659796

Azelaic Acid Exerts Antileukemic Activity in Acute Myeloid Leukemia.

PubMed

Pan, Yunbao; Liu, Dong; Wei, Yongchang; Su, Dan; Lu, Chenyang; Hu, Yanchao; Zhou, Fuling

2017-01-01

Acute myeloid leukemia (AML) is an acute leukemia common in most adults; its prevalence intensifies with age. The overall survival of AML is very poor because of therapeutic resistance. Azelaic acid (AZA) is non-toxic, non-teratogenic, and non-mutagenic and its antitumor effect on various tumor cells is well established; Nonetheless, its therapeutic effects in AML cells are largely unknown. In this study, it was shown that AZA significantly inhibits the cell viability and induces apoptosis in AML cells in a dose-dependent manner. Additionally, AZA suppressed the expression of phosphorylated Akt, Jab1 and Trx, and this suppression was enhanced by treatment with Jab1 siRNA. Furthermore, AZA sensitized AML cells to Ara-c chemotherapy. The suppressive effect of AZA on tumor growth was examined in vivo by subcutaneously inoculated AML cells in a tumor model using nude mice. These findings indicate that AZA is useful as an effective ingredient in antineoplastic activity.

A randomized comparative trial of a combined oral contraceptive and azelaic acid to assess their effect on sleep quality in adult female acne patients.

PubMed

Albuquerque, Rachel Gimenes; da Rocha, Marco Alexandre Dias; Hirotsu, Camila; Hachul, Helena; Bagatin, Edileia; Tufik, Sergio; Andersen, Monica Levy

2015-12-01

Several studies have reported an increase in the prevalence of adult female acne. This subtype of acne presents particular characteristics, and can be triggered by several factors such as smoking, stress, the use of oily cosmetics and even by poor sleep. Sleep quality is related to well-being and the maintenance of body homeostasis. In addition, several skin diseases present a bidirectional relationship with sleep, demonstrating an important connection between skin and the central nervous system. With this in mind, we aimed to compare the effect of two types of treatment for adult female acne (azelaic acid or a combined oral contraceptive) on sleep quality and on concentrations of stress hormones. Also, we proposed to assess the correlation of sleep and hormonal parameters with acne severity. In order to do this, 32 women underwent a clinical evaluation, completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire and had their blood collected for hormone assays. These procedures were performed at baseline and after 6 months of treatment. At baseline there were no differences between the groups in terms of body mass index, age, acne severity and hormone concentrations. Results showed that both treatments demonstrated effectiveness but that women treated with azelaic acid presented a better sleep quality after the treatment compared to baseline and to the group treated with the combined oral contraceptive. The combined oral contraceptive group presented an increase in cortisol and a decrease in free testosterone concentration in relation to baseline. These data suggest that both azelaic acid and combined oral contraceptive are effective in the treatment of adult female acne but, azelaic acid seems to be a more suitable option for those women who may benefit from a better subjective sleep quality.

Similar, but different: structurally related azelaic acid and hexanoic acid trigger differential metabolomic and transcriptomic responses in tobacco cells.

PubMed

Djami-Tchatchou, Arnaud T; Ncube, Efficient N; Steenkamp, Paul A; Dubery, Ian A

2017-11-29

Plants respond to various stress stimuli by activating an enhanced broad-spectrum defensive ability. The development of novel resistance inducers represents an attractive, alternative crop protection strategy. In this regard, hexanoic acid (Hxa, a chemical elicitor) and azelaic acid (Aza, a natural signaling compound) have been proposed as inducers of plant defense, by means of a priming mechanism. Here, we investigated both the mode of action and the complementarity of Aza and Hxa as priming agents in Nicotiana tabacum cells in support of enhanced defense. Metabolomic analyses identified signatory biomarkers involved in the establishment of a pre-conditioned state following Aza and Hxa treatment. Both inducers affected the metabolomes in a similar manner and generated common biomarkers: caffeoylputrescine glycoside, cis-5-caffeoylquinic acid, feruloylglycoside, feruloyl-3-methoxytyramine glycoside and feruloyl-3-methoxytyramine conjugate. Subsequently, quantitative real time-PCR was used to investigate the expression of inducible defense response genes: phenylalanine ammonia lyase, hydroxycinnamoyl CoA quinate transferase and hydroxycinnamoyl transferase to monitor activation of the early phenylpropanoid pathway and chlorogenic acids metabolism, while ethylene response element-binding protein, small sar1 GTPase, heat shock protein 90, RAR1, SGT1, non-expressor of PR genes 1 and thioredoxin were analyzed to report on signal transduction events. Pathogenesis-related protein 1a and defensin were quantified to investigate the activation of defenses regulated by salicylic acid and jasmonic acid respectively. The qPCR results revealed differential expression kinetics and, in general (except for NPR1, Thionin and PR1a), the relative gene expression ratios observed in the Hxa-treated cells were significantly greater than the expression observed in the cells treated with Aza. The results indicate that Aza and Hxa have a similar priming effect through activation of genes

Arabidopsis ENHANCED DISEASE SUSCEPTIBILITY1 promotes systemic acquired resistance via azelaic acid and its precursor 9-oxo nonanoic acid

PubMed Central

Wittek, Finni; Hoffmann, Thomas; Kanawati, Basem; Bichlmeier, Marlies; Knappe, Claudia; Wenig, Marion; Schmitt-Kopplin, Philippe; Parker, Jane E.; Schwab, Wilfried; Vlot, A. Corina

2014-01-01

Systemic acquired resistance (SAR) is a form of inducible disease resistance that depends on salicylic acid and its upstream regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). Although local Arabidopsis thaliana defence responses activated by the Pseudomonas syringae effector protein AvrRpm1 are intact in eds1 mutant plants, SAR signal generation is abolished. Here, the SAR-specific phenotype of the eds1 mutant is utilized to identify metabolites that contribute to SAR. To this end, SAR bioassay-assisted fractionation of extracts from the wild type compared with eds1 mutant plants that conditionally express AvrRpm1 was performed. Using high-performance liquid chromatography followed by mass spectrometry, systemic immunity was associated with the accumulation of 60 metabolites, including the putative SAR signal azelaic acid (AzA) and its precursors 9-hydroperoxy octadecadienoic acid (9-HPOD) and 9-oxo nonanoic acid (ONA). Exogenous ONA induced SAR in systemic untreated leaves when applied at a 4-fold lower concentration than AzA. The data suggest that in planta oxidation of ONA to AzA might be partially responsible for this response and provide further evidence that AzA mobilizes Arabidopsis immunity in a concentration-dependent manner. The AzA fragmentation product pimelic acid did not induce SAR. The results link the C9 lipid peroxidation products ONA and AzA with systemic rather than local resistance and suggest that EDS1 directly or indirectly promotes the accumulation of ONA, AzA, or one or more of their common precursors possibly by activating one or more pathways that either result in the release of these compounds from galactolipids or promote lipid peroxidation. PMID:25114016

Arabidopsis ENHANCED DISEASE SUSCEPTIBILITY1 promotes systemic acquired resistance via azelaic acid and its precursor 9-oxo nonanoic acid.

PubMed

Wittek, Finni; Hoffmann, Thomas; Kanawati, Basem; Bichlmeier, Marlies; Knappe, Claudia; Wenig, Marion; Schmitt-Kopplin, Philippe; Parker, Jane E; Schwab, Wilfried; Vlot, A Corina

2014-11-01

Systemic acquired resistance (SAR) is a form of inducible disease resistance that depends on salicylic acid and its upstream regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). Although local Arabidopsis thaliana defence responses activated by the Pseudomonas syringae effector protein AvrRpm1 are intact in eds1 mutant plants, SAR signal generation is abolished. Here, the SAR-specific phenotype of the eds1 mutant is utilized to identify metabolites that contribute to SAR. To this end, SAR bioassay-assisted fractionation of extracts from the wild type compared with eds1 mutant plants that conditionally express AvrRpm1 was performed. Using high-performance liquid chromatography followed by mass spectrometry, systemic immunity was associated with the accumulation of 60 metabolites, including the putative SAR signal azelaic acid (AzA) and its precursors 9-hydroperoxy octadecadienoic acid (9-HPOD) and 9-oxo nonanoic acid (ONA). Exogenous ONA induced SAR in systemic untreated leaves when applied at a 4-fold lower concentration than AzA. The data suggest that in planta oxidation of ONA to AzA might be partially responsible for this response and provide further evidence that AzA mobilizes Arabidopsis immunity in a concentration-dependent manner. The AzA fragmentation product pimelic acid did not induce SAR. The results link the C9 lipid peroxidation products ONA and AzA with systemic rather than local resistance and suggest that EDS1 directly or indirectly promotes the accumulation of ONA, AzA, or one or more of their common precursors possibly by activating one or more pathways that either result in the release of these compounds from galactolipids or promote lipid peroxidation. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Impact of order of application of moisturizers on percutaneous absorption kinetics: evaluation of sequential application of moisturizer lotions and azelaic acid gel 15% using a human skin model.

PubMed

Del Rosso, James Q; Lehman, Paul A; Raney, Sam G

2009-03-01

The medical management of rosacea increasingly has involved not only the appropriate selection of topical medication but also patient education and specific recommendations regarding appropriate skin care. The recognition that epidermal barrier dysfunction and transepidermal water loss (TEWL) play a pathophysiologic role in rosacea and that skin moisturization may help to mitigate signs and symptoms of the disease has led to a deeper appreciation of the importance of proper skin care in the treatment of rosacea. Data from a percutaneous penetration study performed using human skin suggest that any of the tested moisturizer lotions may be applied either before or after azelaic acid gel 15% without a major change in the percutaneous absorption profile of azelaic acid.

Azelaic acid 20 % cream: effects on quality of life and disease severity in adult female acne patients.

PubMed

Kainz, Julius Thomas; Berghammer, Gabriele; Auer-Grumbach, Piet; Lackner, Verena; Perl-Convalexius, Sylvia; Popa, Rodica; Wolfesberger, Barbara

2016-12-01

Data on the efficacy of acne treatments and their impact on quality of life (QoL) in adult patients is sketchy. Assessment of the efficacy of azelaic acid 20 % cream (Skinoren ® ) on acne severity and disease-related QoL. Noninterventional study in adult female patients with mild to moderate acne. Efficacy variables included DLQI and acne severity on the face, chest, and back using the Investigator's Global Assessment (IGA) scale (grade 1 = nearly clear skin; 2 = mild acne; 3 = moderate acne). Visits were scheduled at baseline, at 4-8 weeks, and at twelve weeks. Of the 251 women enrolled, 59 % had grade 1 acne at baseline; 31 %, grade 2; and 10 %, grade 3; the most commonly affected area of the body was the face (IGA grades 2 or 3: 79 %). After twelve weeks, there was significant improvement of acne on the face (IGA grades 0 or 1: 82 %), chest, and back. Median DLQI decreased from nine at baseline to five after twelve weeks. Ninety percent of physicians and patients rated the tolerability of the treatment as very good or good. Treatment with azelaic acid 20 % cream significantly improves acne severity and disease-related QoL in adult women. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Lipid profiling of the Arabidopsis hypersensitive response reveals specific lipid peroxidation and fragmentation processes: biogenesis of pimelic and azelaic acid.

PubMed

Zoeller, Maria; Stingl, Nadja; Krischke, Markus; Fekete, Agnes; Waller, Frank; Berger, Susanne; Mueller, Martin J

2012-09-01

Lipid peroxidation (LPO) is induced by a variety of abiotic and biotic stresses. Although LPO is involved in diverse signaling processes, little is known about the oxidation mechanisms and major lipid targets. A systematic lipidomics analysis of LPO in the interaction of Arabidopsis (Arabidopsis thaliana) with Pseudomonas syringae revealed that LPO is predominantly confined to plastid lipids comprising galactolipid and triacylglyceride species and precedes programmed cell death. Singlet oxygen was identified as the major cause of lipid oxidation under basal conditions, while a 13-lipoxygenase (LOX2) and free radical-catalyzed lipid oxidation substantially contribute to the increase upon pathogen infection. Analysis of lox2 mutants revealed that LOX2 is essential for enzymatic membrane peroxidation but not for the pathogen-induced free jasmonate production. Despite massive oxidative modification of plastid lipids, levels of nonoxidized lipids dramatically increased after infection. Pathogen infection also induced an accumulation of fragmented lipids. Analysis of mutants defective in 9-lipoxygenases and LOX2 showed that galactolipid fragmentation is independent of LOXs. We provide strong in vivo evidence for a free radical-catalyzed galactolipid fragmentation mechanism responsible for the formation of the essential biotin precursor pimelic acid as well as of azelaic acid, which was previously postulated to prime the immune response of Arabidopsis. Our results suggest that azelaic acid is a general marker for LPO rather than a general immune signal. The proposed fragmentation mechanism rationalizes the pathogen-induced radical amplification and formation of electrophile signals such as phytoprostanes, malondialdehyde, and hexenal in plastids.

The effect on acne quality of life of topical azelaic acid 15% gel versus a combined oral contraceptive in adult female acne: A randomized trial.

PubMed

Rocha, Marco; Sanudo, Adriana; Bagatin, Edileia

2017-01-01

Acne vulgaris is a chronic inflammatory disease that affects the pilosebaceous unit. Recent studies have shown an increasing number of cases of acne in adult women. These cases are predominantly normoandrogenic and have show some clinical differences compared to adolescent acne. In addition to the physical aspects, acne has a strong psychosocial impact and can lead to the onset of signs and symptoms of depression, such as anger. Our objective was to evaluate the effect on acne-specific quality of life in adult women treated with topical azelaic acid versus a combined oral contraceptive. The study population consisted of 38 adult women with acne and without any features of hyperandrogenism recruited from the clinic of Dermatology Hospital Division of São Paulo, Federal University of São Paulo from January 2012 to September 2014. Patients were randomized into two different groups: one receiving containing 20 ug of ethinylestradiol and 3 mg drospirenone in a regimen of 24 days of medication, a combined oral contraceptive (COC), and the other group topical 15% azelaic acid (AA) gel, twice daily, both for six months. The quality of life was evaluated at baseline and end of treatment with an acne specific measure (Acne-QoL). Before treatment, our data revealed a significant impact of the presence of acne on quality of life. Both treatments resulted in improvement with significant statistical values in quality of life scores. Comparing the four domains of Acne-QoL, patients treated with an oral contraceptive showed greater improvement in two domains (self-perception and acne symptoms) than those treated with azelaic acid.

Molecular determinants of the olfactory receptor Olfr544 activation by azelaic acid.

PubMed

Thach, Trung Thanh; Hong, Yu-Jung; Lee, Sangho; Lee, Sung-Joon

2017-04-01

The mouse olfactory receptor Olfr544 is expressed in several non-olfactory tissues and has been suggested as a functional receptor regulating different signaling pathways. However, the molecular interaction between Olfr544 and its natural ligand, azelaic acid (AzA), remains poorly characterized, primarily due to difficulties in the heterologous expression of the receptor protein on the cell membrane and lack of entire protein structure. In this report, we describe the molecular determinants of Olfr544 activation by AzA. N-terminal lucy-flag-rho tag ensured the heterologous expression of Olfr544 on the Hana3A cell surface. Molecular modeling and docking combined with mutational analysis identified amino acid residues in the Olfr544 for the interaction with AzA. Our data demonstrated that the Y109 residue in transmembrane helix 3 forms a hydrogen bond with AzA, which is crucial for the receptor-ligand interaction and activation. Y109 is required for the Olfr544 activation by AzA which, in turn, stimulates the Olfr544-dependent CREB-PGC-1α signaling axis and is followed by the induction of mitochondrial biogenesis in Olfr544 wild-type transfected Hana3A cells, but not in mock or Y109A mutant transfected cells. Collectively, these data indicated that a hydrogen bond between Y109 residue and AzA is a major determinant of the Olfr544-AzA interaction and activation. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of a gas chromatography method for azelaic acid determination in selected biological samples

PubMed Central

Garelnabi, Mahdi; Litvinov, Dmitry; Parthasarathy, Sampath

2010-01-01

Background: Azelaic acid (AzA) is the best known dicarboxilic acid to have pharmaceutical benefits and clinical applications and also to be associated with some diseases pathophysiology. Materials and Methods: We extracted and methylesterified AzA and determined its concentration in human plasma obtained from healthy individuals and also in mice fed AzA containing diet for three months. Results: AzA was detected in Gas Chromatography (GC) and confirmed by Liquid chromatography mass spectrometry (LCMS), and gas chromatography mass spectrometry (GCMC). Our results have shown that AzA can be determined efficiently in selected biological samples by GC method with 1nM limit of detection (LoD) and the limit of quantification (LoQ); was established at 50nM. Analytical Sensitivity as assayed by hexane demonstrated an analytical sensitivity at 0.050nM. The method has demonstrated 8-10% CV batch repeatability across the sample types and 13-18.9% CV for the Within-Lab Precision analysis. The method has shown that AzA can efficiently be recovered from various sample preparation including liver tissue homogenate (95%) and human plasma (97%). Conclusions: Because of its simplicity and lower limit of quantification, the present method provides a useful tool for determining AzA in various biological sample preparations. PMID:22558586

Effect of combination of taurine and azelaic acid on antimelanogenesis in murine melanoma cells

PubMed Central

2010-01-01

Background Pigmentation in human skin is an important defense mechanism against sunlight or oxidative stress. Despite the protective role of melanin, abnormal hyperpigmentation such as freckles and chloasma sometimes can be serious aesthetic problems. Because of these effects of hyperpigmentation, people have considered the effect of depigmentation. Azelaic acid (AZ) is a saturated dicarboxylic acid found naturally in wheat, rye, and barley. Previously, we showed that AZ inhibited melanogenesis. In this study, we investigated the antimelanogenic activity of combination of AZ and taurine (Tau) in B16F10 mouse melanoma cells. Methods The mouse melanoma cell line B16F10 was used in the study. We measured melanin contents and tyrosinase activity. To gain the change of protein expression, we carried out western blotting. Results We investigated that AZ combined with taurine (Tau) show more inhibitory effects in melanocytes than the treatment of AZ alone. AZ combined with Tau inhibited the melanin production and tyrosinase activity of B16F10 melanoma cells without significant cytotoxicity. Also inhibitory effects after treatment with these combined chemical are stronger than AZ alone on melanogenesis. Conclusions These findings indicate that AZ with Tau might play an important role in the regulation of melanin formation and be useful as effective ingredients in antimelanogesis. PMID:20804622

Evaluation of a gas chromatography method for azelaic acid determination in selected biological samples.

PubMed

Garelnabi, Mahdi; Litvinov, Dmitry; Parthasarathy, Sampath

2010-09-01

Azelaic acid (AzA) is the best known dicarboxilic acid to have pharmaceutical benefits and clinical applications and also to be associated with some diseases pathophysiology. We extracted and methylesterified AzA and determined its concentration in human plasma obtained from healthy individuals and also in mice fed AzA containing diet for three months. AzA was detected in Gas Chromatography (GC) and confirmed by Liquid chromatography mass spectrometry (LCMS), and gas chromatography mass spectrometry (GCMC). Our results have shown that AzA can be determined efficiently in selected biological samples by GC method with 1nM limit of detection (LoD) and the limit of quantification (LoQ); was established at 50nM. Analytical Sensitivity as assayed by hexane demonstrated an analytical sensitivity at 0.050nM. The method has demonstrated 8-10% CV batch repeatability across the sample types and 13-18.9% CV for the Within-Lab Precision analysis. The method has shown that AzA can efficiently be recovered from various sample preparation including liver tissue homogenate (95%) and human plasma (97%). Because of its simplicity and lower limit of quantification, the present method provides a useful tool for determining AzA in various biological sample preparations.

Effect of combination of taurine and azelaic acid on antimelanogenesis in murine melanoma cells.

PubMed

Yu, Ji Sun; Kim, An Keun

2010-08-24

Pigmentation in human skin is an important defense mechanism against sunlight or oxidative stress. Despite the protective role of melanin, abnormal hyperpigmentation such as freckles and chloasma sometimes can be serious aesthetic problems. Because of these effects of hyperpigmentation, people have considered the effect of depigmentation. Azelaic acid (AZ) is a saturated dicarboxylic acid found naturally in wheat, rye, and barley. Previously, we showed that AZ inhibited melanogenesis. In this study, we investigated the antimelanogenic activity of combination of AZ and taurine (Tau) in B16F10 mouse melanoma cells. The mouse melanoma cell line B16F10 was used in the study. We measured melanin contents and tyrosinase activity. To gain the change of protein expression, we carried out western blotting. We investigated that AZ combined with taurine (Tau) show more inhibitory effects in melanocytes than the treatment of AZ alone. AZ combined with Tau inhibited the melanin production and tyrosinase activity of B16F10 melanoma cells without significant cytotoxicity. Also inhibitory effects after treatment with these combined chemical are stronger than AZ alone on melanogenesis. These findings indicate that AZ with Tau might play an important role in the regulation of melanin formation and be useful as effective ingredients in antimelanogesis.

Safety assessment of azelaic acid and its derivatives entrapped in nanovesicles.

PubMed

Panyosak, A; Manosroi, J; Rojanasakul, Y; Manosroi, A

2009-06-01

The aim of this study was to determine the safety of azelaic acid (AA) and its derivatives in nanovesicles for pharmaceutical and cosmetic uses. The hydrophilic property of AA was modified by complexing AA with hydroxypropyl-beta-cyclodextrin (AACD). The lipophilic property of AA was improved to diethyl azelate (DA) by esterification with Fischer reaction. AA, AACD and DA were entrapped in liposomes and niosomes with the compositions of L-alpha-dipalmitoyl phosphatidylcholine/cholesterol = 7:3 and Tween 61/cholesterol = 1:1, respectively, by chloroform film method with sonication. The size of the vesicles ranged from 50 to 200 nm, indicating nanosize characteristics. The cytotoxicity of AA, AACD and DA entrapped nanovesicular formulations on mouse epidermal cell lines (JB6, normal cell lines) by the sulforhodamine B assay was modest when compared with cisplatin. Blank liposomes and niosomes gave no growth inhibitory effect. The irritation of AA, AACD and DA entrapped and not entrapped in nanovesicles on rabbit skin was examined according to the Environmental Protection Agency health effect test guidelines. The results showed no signs of erythema or edema within 72 h. AA and its derivatives were safe for topical use when entrapped in nanovesicles because of no toxicity to normal cell lines and no allergy on rabbit skin.

Lipid Profiling of the Arabidopsis Hypersensitive Response Reveals Specific Lipid Peroxidation and Fragmentation Processes: Biogenesis of Pimelic and Azelaic Acid1[C][W

PubMed Central

Zoeller, Maria; Stingl, Nadja; Krischke, Markus; Fekete, Agnes; Waller, Frank; Berger, Susanne; Mueller, Martin J.

2012-01-01

Lipid peroxidation (LPO) is induced by a variety of abiotic and biotic stresses. Although LPO is involved in diverse signaling processes, little is known about the oxidation mechanisms and major lipid targets. A systematic lipidomics analysis of LPO in the interaction of Arabidopsis (Arabidopsis thaliana) with Pseudomonas syringae revealed that LPO is predominantly confined to plastid lipids comprising galactolipid and triacylglyceride species and precedes programmed cell death. Singlet oxygen was identified as the major cause of lipid oxidation under basal conditions, while a 13-lipoxygenase (LOX2) and free radical-catalyzed lipid oxidation substantially contribute to the increase upon pathogen infection. Analysis of lox2 mutants revealed that LOX2 is essential for enzymatic membrane peroxidation but not for the pathogen-induced free jasmonate production. Despite massive oxidative modification of plastid lipids, levels of nonoxidized lipids dramatically increased after infection. Pathogen infection also induced an accumulation of fragmented lipids. Analysis of mutants defective in 9-lipoxygenases and LOX2 showed that galactolipid fragmentation is independent of LOXs. We provide strong in vivo evidence for a free radical-catalyzed galactolipid fragmentation mechanism responsible for the formation of the essential biotin precursor pimelic acid as well as of azelaic acid, which was previously postulated to prime the immune response of Arabidopsis. Our results suggest that azelaic acid is a general marker for LPO rather than a general immune signal. The proposed fragmentation mechanism rationalizes the pathogen-induced radical amplification and formation of electrophile signals such as phytoprostanes, malondialdehyde, and hexenal in plastids. PMID:22822212

[Antibiotics, azelaic acid and benzoyl peroxide in topical acne therapy].

PubMed

Fluhr, Joachim W; Degitz, Klaus

2010-03-01

Benzoyl peroxide was introduced as a basic treatment already in acne therapy 1934. The mechanism of action is the reduction of anaerobe bacteria by strong oxidation processes. No resistancies have been ever reported. BPO is available in 2.5, 5 and 10 % formulations. Its efficacy is slightly related to the strength of concentrations, but the side effect profile with burning, erythema and desquamation is increasing with concentrations. BPO 5% mostly is efficient enough to control acne of grades I to II according to the Kligman & Plewig classification. BPO my bleach clothes and hair. It is the most costeffective topical drug in acne of grades I-II. Inflammatory acne of the papular-pustular type I-II can also be treated by topical antibiotics such as erythromycin, clindamycin, and, less frequent and today not anymore recommended tetracyclines. Mechanism of action is not alone an antibacterial but anti inflammatory effect. The efficacy and penetration of the topical antibiotics between the groups are similar. Randomized studies have shown that concentrations of 2-4% are equivalent to oral tetracycline and minocycline in mild to moderate acne. Combinatory formulations with BPO and with retinoids enhance the efficacy significantly. Topical antibiotics plus BPO show less bacterial resistancies as topical antibiotics alone. Antibiotics should therefore not be used as monotherapy. Moreover gram negative folliculitis may develop. Azelaic acid is acting as an antimicrobial and can also reduce comedones. It can also be used in pregnancy and during the lactation period.

High abundances of oxalic, azelaic, and glyoxylic acids and methylglyoxal in the open ocean with high biological activity: Implication for secondary OA formation from isoprene

NASA Astrophysics Data System (ADS)

Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo; Fu, Pingqing

2014-05-01

Atmospheric dicarboxylic acids (DCA) are a ubiquitous water-soluble component of secondary organic aerosols (SOA), which can act as cloud condensation nuclei (CCN), affecting the Earth's climate. Despite the high abundances of oxalic acid and related compounds in the marine aerosols, there is no consensus on what controls their distributions over the open ocean. Marine biological productivity could play a role in the production of DCA, but there is no substantial evidence to support this hypothesis. Here we present latitudinal distributions of DCA, oxoacids and α-dicarbonyls in the marine aerosols from the remote Pacific. Their concentrations were found several times higher in more biologically influenced aerosols (MBA) than less biologically influenced aerosols. We propose isoprene and unsaturated fatty acids as sources of DCA as inferred from significantly higher abundances of isoprene-SOA tracers and azelaic acid in MBA. These results have implications toward the reassessment of climate forcing feedbacks of marine-derived SOA.

Azelaic acid gel 15% in the management of papulopustular rosacea: a status report on available efficacy data and clinical application.

PubMed

Del Rosso, James Q; Bhatia, Neal

2011-08-01

Azelaic acid (AzA) gel 15% is approved by the US Food and Drug Administration (FDA) for the treatment of papulopustular rosacea (PPR). Its efficacy and safety as monotherapy have been demonstrated. Release of active drug from the gel formulation is superior to the cream. The combination of AzA gel 15% with oral doxycycline appears to expedite and augment response, especially in cases of PPR of greater severity, and AzA gel 15% maintains control of PPR over 6 months as compared to vehicle. Adjunctive skin care is recommended to augment the therapeutic outcome of PPR and reduce the potential for irritation that can occur with topical therapy.

Combination of glycolic acid peel and topical 20% azelaic acid cream in melasma patients: efficacy and improvement in quality of life.

PubMed

Dayal, Surabhi; Sahu, Priyadarshini; Dua, Ruchika

2017-03-01

Glycolic acid (GA) peel is one of the most versatile agents in the treatment of melasma. GA peeling alone or in combination with topical hypopigmenting agents has shown encouraging results. However, there is paucity of controlled trial demonstrating the efficacy of glycolic peel in conjunction with topical azelaic acid (AA). We therefore sought to highlight the efficacy and safety of this combination in melasma. To assess the clinical efficacy, safety and reduction in melasma quality of life (MELASQOL) scores on combining serial GA peels with topical 20% AA cream in epidermal melasma. Sixty patients of epidermal melasma were enrolled for 24 weeks. Patients were divided into two groups: (1) Study group received serial GA peel every 3 weeks with twice daily 20% AA cream, and (2) control group received only 20% AA cream. Clinical improvement was assessed objectively using Melasma Area Severity Index (MASI). Melasma-related quality of life was measured by MELASQOL scale in both groups. Side effects were observed at each visit. The improvement in MASI and percentage decrease in MASI scoring were statistically significant 12 weeks onwards in study group as compared to control group. There was also a significant reduction in MELASQOL scores in study group as compared to control group after treatment. Minor reversible side effects were observed in both groups, which did not require cessation of therapy. GA peel enhances therapeutic efficacy of topical AA cream for treatment of melasma, with improvement in quality of life without serious side effects. © 2016 Wiley Periodicals, Inc.

Combination of azelaic acid 5% and erythromycin 2% in the treatment of acne vulgaris.

PubMed

Pazoki-Toroudi, Hamidreza; Nassiri-Kashani, Mansour; Tabatabaie, Hossein; Ajami, Marjan; Habibey, Rouhollah; Shizarpour, Mohammad; Babakoohi, Shahab; Rahshenas, Makan; Firooz, Alireza

2010-05-01

Acne vulgaris is a common problem, particularly among adolescents, which is usually resistant to monotherapy. We evaluated the efficacy and safety of a combination of azelaic acid (AA) 5% and erythromycin 2% gel (AzE) compared with AA 20% or erythromycin 2% gels in facial acne vulgaris. We conducted a 12-week, multicenter, randomized double-blind study on 147 patients with mild-to-moderate acne vulgaris. Four treatment group were determined (placebo, erythromycin, AA and AzE) and followed in 4-week intervals for 12 weeks, except the placebo group which was changed to routine treatment after 4 weeks. The combination of AA 5% and erythromycin 2% gel significantly reduced the number of papules, pustules and comedones compared with placebo (p < 0.001), erythromycin 2% (p < 0.01) or AA 20% (p < 0.05). The incidence of adverse effects observed in patients treated with AzE (27%) was less than that with erythromycin 2% (54%) and AA 20% (45%). The combination of AA 5% and erythromycin 2% produced more potent therapeutic effects in comparison with erythromycin 2% or AA 20% alone, and with fewer side effects.

Azelaic acid was sensitizing effect in the chemotherapeutic treatment of several melanoma cell lines.

PubMed

Rodriguez-Vicente, J; Vicente-Ortega, V; Canteras-Jordana

1996-12-01

Chemotherapy for melanoma results in low response and must be reinforced with sensitizer compounds. We believed that azelaic acid (AZA) could modulate melanomas' resistance to antineoplastics. Therefore we tried to compare in vitro treatment with antineoplastics alone versus AZA treatment followed by antineoplastics. We carried out MTT assays to evaluate the cytotoxicity of melphalan, lomustine (CCNU), fotemustine, and 4-Hydroxyanisole (4-HA) on three melanoma lines (B16F10, SK-MEL-28, and SK-MEL-1), and the modulating effect of pretreatment with AZA (1 mM). AZA showed a dose-dependent antineoplastic activity on the three lines. Melphalan was the most active drug followed by CCNU, fotemustine, and 4-HA. The most sensitive line was B16F10 and the least sensitive was SK-meL-1. Previous treatment with AZA of B16F10 reinforced the effect of melphalan (2.5 times), CCNU (10 times), and fotemustine (14 times); whereas for SK-MEL-28 and SK-MEL-1, only the cytotoxicity of CCNU and fotemustine increased. An antagonist effect was produced by 4-HA on all three lines. We concluded that AZA enhances in vitro cytotoxicity of CCNU and fotemustine.

Monomeric and dimeric structures, electronic properties and vibrational spectra of azelaic acid by HF and B3LYP methods

NASA Astrophysics Data System (ADS)

Kumar, Amarendra; Narayan, Vijay; Prasad, Onkar; Sinha, Leena

2012-08-01

Quantum chemical calculations of energies, dipole moment, polarizability, hyperpolarizability and vibrational wavenumbers of Azelaic acid (AZA) were carried out by using ab initio HF and B3LYP methods with 6-311++G(d,p) basis set. Hydrogen-bonded dimer of AZA, optimized by counterpoise correction, has also been studied by HF and B3LYP at the 6-311++G(d,p) level and the effects of molecular association through Osbnd H⋯O hydrogen bonding have been discussed. A complete vibrational analysis of AZA has been performed and assignments are made on the basis of potential energy distribution. The comparisons and assignments of the vibrational frequencies indicate that the experimental spectra also correspond acceptably with those of theoretically simulated spectra except the hydrogen-bonded coupled infrared vibrations.

Azelaic acid 15% gel once daily versus twice daily in papulopustular rosacea.

PubMed

Thiboutot, Diane M; Fleischer, Alan B; Del Rosso, James Q; Graupe, Klaus

2008-06-01

Twice-daily azelaic acid (AzA) is the conventional regimen for papulopustular rosacea, but once-daily AzA may be equally effective, with greater convenience and dosing flexibility. In order to test this hypothesis, an exploratory study was conducted. The evaluable efficacy population of this 12-week double-blind, parallel-group study included 72 patients and the population that was used to report safety results included 92 patients. Baseline characteristics were comparable between the once-daily and twice-daily study groups. Evaluations were performed at baseline and at weeks 4, 8, and 12. No significant difference was found between the once-daily and twice-daily groups at the end of study therapy in mean investigator global assessment (IGA) scores, treatment success, or treatment response. The mean number of inflammatory lesions, the intensity of erythema intensity, and the intensity of telangiectasia at treatment end were likewise not significantly different (P>.205 for all). More than 90% of subjects in each group rated cosmetic acceptability of this AzA gel as satisfactory or better. Based on these findings and those of prior studies, once-daily AzA 15% gel can therefore be utilized as a safe, effective, and economical dosing option for the treatment of mild-to-moderate papulopustular rosacea. Once-daily dosing of AzA 15% gel was well accepted by patients and can offer considerable dosing flexibility and convenience for the patient as well as for the dermatologist.

Efficacy of extended-release 45 mg oral minocycline and extended-release 45 mg oral minocycline plus 15% azelaic acid in the treatment of acne rosacea.

PubMed

Jackson, J Mark; Kircik, Leon H; Lorenz, Douglas J

2013-03-01

Rosacea is one of the most commonly occurring dermatoses treated by dermatologists. There are multiple therapeutic options available for the treatment of papulopustular rosacea. Rosacea is an inflammatory condition, classically presenting with flushing and/or blushing along with erythema, edema, telangiectasia, papules, pustules, and nodules of the face. Minocycline, a member of the tetracycline family, has demonstrated benefit in the treatment of inflammatory lesions in patients with rosacea. This manuscript highlights the use of a new sustained-release low-dose minocycline 45 mg tablet, with or without azelaic acid, for the treatment of papulopustular rosacea.

A feedback regulatory loop between G3P and lipid transfer proteins DIR1 and AZI1 mediates azelaic-acid-induced systemic immunity.

PubMed

Yu, Keshun; Soares, Juliana Moreira; Mandal, Mihir Kumar; Wang, Caixia; Chanda, Bidisha; Gifford, Andrew N; Fowler, Joanna S; Navarre, Duroy; Kachroo, Aardra; Kachroo, Pradeep

2013-04-25

Systemic acquired resistance (SAR), a highly desirable form of plant defense, provides broad-spectrum immunity against diverse pathogens. The recent identification of seemingly unrelated chemical inducers of SAR warrants an investigation of their mutual interrelationships. We show that SAR induced by the dicarboxylic acid azelaic acid (AA) requires the phosphorylated sugar derivative glycerol-3-phosphate (G3P). Pathogen inoculation induced the release of free unsaturated fatty acids (FAs) and thereby triggered AA accumulation, because these FAs serve as precursors for AA. AA accumulation in turn increased the levels of G3P, which is required for AA-conferred SAR. The lipid transfer proteins DIR1 and AZI1, both of which are required for G3P- and AA-induced SAR, were essential for G3P accumulation. Conversely, reduced G3P resulted in decreased AZI1 and DIR1 transcription. Our results demonstrate that an intricate feedback regulatory loop among G3P, DIR1, and AZI1 regulates SAR and that AA functions upstream of G3P in this pathway. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Characteristics and anti-proliferative activity of azelaic acid and its derivatives entrapped in bilayer vesicles in cancer cell lines.

PubMed

Manosroi, Aranya; Panyosak, Atchara; Rojanasakul, Yon; Manosroi, Jiradej

2007-06-01

The hydrophilicity and lipophilicity of azelaic acid (AA) were modified to diethyl azelate (DA) which was synthesized by Fisher esterification reaction and identified by IR, MS and (1)H NMR and to azelaic acid-beta-cyclodextrin complex (AACD) which was prepared by inclusion complexation and identified by IR, DSC and XRD respectively. AA, DA and AACD were entrapped in liposomes and niosomes comprising of L-alpha-dipalmitoyl phosphatidylcholine (DPPC)/cholesterol at 7:3 molar ratio and Tween61/cholesterol at 1:1 molar ratio, respectively, using a thin-film hydration method with sonication. The size and morphology of these bilayer vesicles were determined by optical and transmission electron microscopy. The particle size was found to be in the range of 90-190 nm. The entrapment efficiency of AA, DA and AACD in all vesicular formulations was more than 80%, as analyzed by HPLC for AA and AACD, and GC for DA. Anti-proliferative activity of AA and its derivatives (DA and AACD) both entrapped and not entrapped in bilayer vesicles, using MTT assay in three cancer cell lines (HeLa, KB and B(16)F(10)) comparing with vincristine, were investigated. AACD showed the highest potency comparing to AA in HeLa, KB and B(16)F(10) of 1.48, 1.6 and 1.5 times, respectively. AA entrapped in liposomes was about 90 times more potent than the free AA, and about 1.5 times less potent than vincristine. When entrapped in bilayer vesicles, DA and AACD were more effective than AA in killing cancer cells. AACD entrapped in liposomes gave the highest anti-proliferation activity in HeLa cell lines with the IC(50) of 2.3 and 327 times more potent than vincristine and AA, respectively. DA in liposomes demonstrated the IC(50) of 0.03 times less potent than vincristine in KB cell lines, while in B(16)F(10) AACD in niosomes showed the IC(50) of 0.05 times less potent than vincristine. This study has suggested that the modification of AA by derivatization and complexation as well as the entrapment in

Effect of ionization and vehicle on skin absorption and penetration of azelaic acid.

PubMed

Li, Nan; Wu, Xiaohong; Jia, Weibu; Zhang, Michelle C; Tan, Fengping; Zhang, Jerry

2012-08-01

The aim of this study is to investigate the effect of ionization and vehicle of topical formulations on skin absorption and penetration of azelaic acid (AZA). In vitro transport of AZA was determined for two topical formulations containing AZA with pH values of 3.9 and 4.9, respectively. FINACEA(®) (15% AZA gel), a US Food and Drug Administration approved drug for treatment of acne and rosacea, was also used for comparison. Release profile and flux of AZA were determined in an in vitro hairless mouse skin model using Franz Diffusion Cell. The data have shown that a higher concentration of AZA is retained in the epidermis/dermis layer and the whole skin for the formulation with pH = 4.9 as compared to that with pH = 3.9 at an active loading level of 2.82 mg/cm(2). In addition, the flux of ionized species of AZA in the pH 4.9 formulation (128.4 ± 35.9 μg/cm(2)/h) is approximately five-fold greater than that in the pH 3.9 formulation (27.7 ± 4.0 μg/cm(2)/h). The results suggest that the ionized AZA penetrates through the skin and accounts for majority of the total flux. This study has demonstrated that the penetration and absorption of AZA show a strong pH- and vehicle-dependency. Solubilization is the rate-limiting step in percutaneous absorption of AZA.

Formulation and characterization of liquid crystal systems containing azelaic acid for topical delivery.

PubMed

Aytekin, Merve; Gursoy, R Neslihan; Ide, Semra; Soylu, Elif H; Hekimoglu, Sueda

2013-02-01

The aim of this study is to prepare and characterize azelaic acid (AzA) containing liquid crystal (LC) drug delivery systems for topical use. Two ternary phase diagrams, containing liquid paraffin as the oil component and a mixture of two nonionic surfactants (Brij 721P and Brij 72), were constructed. Formulations chosen from the phase diagrams were characterized by polarized light microscopy, rheological analyses, differential scanning calorimetry (DSC), and small angle x-ray scattering spectroscopy. Polarized light microscopy proved that except the oil/water emulsion (O/W E), other formulations showed lamellar LC structure. In vitro release studies indicated that the fastest release was achieved by the Lamellar LC (LLC) and O/W E systems, whereas slower release was obtained from the emulsion containing lamellar LC (E-LLC) and distorted lamellar LC (D-LLC) systems. Results of rheological measurements both supported the results of in vitro release studies and showed that the emulsion containing the LC (E-LLC) system had the most stable structure. The formulations and their effect on stratum corneum (SC) were evaluated by DSC studies. The lamellar LC (LLC), emulsion containing lamellar liquid crystal (E-LLC), and O/W E formulations had an effect on both lipid and protein components of SC, whereas distorted lamellar liquid crystal (D-LLC) system had an effect on only the lipid components of SC. LLC systems could be considered promising for the topical delivery of AzA.

Cloud condensation nucleus activity of internally mixed ammonium sulfate/organic acid aerosol particles

NASA Astrophysics Data System (ADS)

Abbatt, J. P. D.; Broekhuizen, K.; Pradeep Kumar, P.

The ability of mixed ammonium sulfate/organic acid particles to act as cloud condensation nuclei (CCN) has been studied in the laboratory using a continuous flow, thermal-gradient diffusion chamber operated at supersaturations between 0.3% and 0.6%. The organic acids studied were malonic acid, azelaic acid, hexanoic acid, cis-pinonic acid, oleic acid and stearic acid, and the particles were largely prepared by condensation of the organic vapor onto a dry ammonium sulfate core. For malonic acid and hexanoic acid, the mixed particles activated as predicted by a simple Köhler theory model where both species are assumed to be fully soluble and the droplet has the surface tension of water. Three low-solubility species, cis-pinonic acid, azelaic acid and oleic acid, are well modeled where the acid was assumed to be either partially or fully insoluble. Interestingly, although thin coats of stearic acid behaved in a manner similar to that displayed by oleic and cis-pinonic acid, we observed that thick coats led to a complete deactivation of the ammonium sulfate, presumably because the water vapor could not diffuse through the solid stearic acid. We observed no CCN behavior that could be clearly attributed to a lowering of the surface tension of the growing droplet by the presence of the organic constituents, some of which are highly surface active.

Piezoelectric crystal microbalance measurements of enthalpy of sublimation of C2-C9 dicarboxylic acids

NASA Astrophysics Data System (ADS)

Dirri, F.; Palomba, E.; Longobardo, A.; Zampetti, E.

2016-02-01

We present here a novel experimental set-up that is able to measure the enthalpy of sublimation of a given compound by means of piezoelectric crystal microbalances (PCMs). The PCM sensors have already been used for space measurements, such as for the detection of organic and non-organic volatile species and refractory materials in planetary environments. In Earth atmospherics applications, PCMs can be also used to obtain some physical-chemical processes concerning the volatile organic compounds (VOCs) present in atmospheric environments. The experimental set-up has been developed and tested on dicarboxylic acids. In this work, a temperature-controlled effusion cell was used to sublimate VOC, creating a molecular flux that was collimated onto a cold PCM. The VOC recondensed onto the PCM quartz crystal, allowing the determination of the deposition rate. From the measurements of deposition rates, it has been possible to infer the enthalpy of sublimation of adipic acid, i.e. ΔHsub : 141.6 ± 0.8 kJ mol-1, succinic acid, i.e. 113.3 ± 1.3 kJ mol-1, oxalic acid, i.e. 62.5 ± 3.1 kJ mol-1, and azelaic acid, i.e. 124.2 ± 1.2 kJ mol-1. The results obtained show an accuracy of 1 % for succinic, adipic, and azelaic acid and within 5 % for oxalic acid and are in very good agreement with previous works (within 6 % for adipic, succinic, and oxalic acid and within 11 % or larger for azelaic acid).

Development and evaluation of a novel topical treatment for acne with azelaic acid-loaded nanoparticles.

PubMed

Reis, Catarina Pinto; Gomes, Ana; Rijo, Patrícia; Candeias, Sara; Pinto, Pedro; Baptista, Marina; Martinho, Nuno; Ascensão, Lia

2013-10-01

Azelaic acid (AzA) is used in the treatment of acne. However, side effects and low compliance have been associated with several topical treatments with AzA. Nanotechnology presents a strategy that can overcome these problems. Polymeric nanoparticles can control drug release and targeting and reduce local drug toxicity. The aim of this study was to produce and evaluate an innovative topical treatment for acne with AzA-loaded poly-DL-lactide/glycolide copolymer nanoparticles. A soft white powder of nanoparticles was prepared. The mean size of loaded nanoparticles was < 400 nm and zeta potential was negative. Spherical nanoparticles were observed by scanning electron microscopy. Encapsulation efficiency was around 80% and a strong interaction between the polymer and the drug was confirmed by differential scanning calorimetric analysis. In vitro drug release studies suggested a controlled and pulsatile release profile. System efficacy tests suggested similar results between the loaded nanoparticles and the nonencapsulated drug against the most common bacteria associated with acne. Cytotoxicity of AzA-loaded nanoparticles was concentration dependent, although not pronounced. The occluded patch test seemed to indicate that the formulation excipients were safe and thus AzA-loaded nanoparticles appear to be an efficient and safe treatment for acne.

Versatility of azelaic acid 15% gel in treatment of inflammatory acne vulgaris.

PubMed

Thiboutot, Diane

2008-01-01

Azelaic acid (AzA) 15% gel is approved for the treatment of rosacea in the US, but also has approval for the treatment of acne vulgaris in many European countries where it has demonstrated success. Two randomized, multicenter, controlled clinical trials compared the effects of AzA 15% gel with those of topical benzoyl peroxide 5% or topical clindamycin 1%, all using a twice-daily dosing regimen. The primary endpoint in the intent-to-treat analysis was a reduction in inflammatory papules and pustules. AzA 15% gel resulted in a 70% to 71% median reduction of facial papules and pustules compared with a 77% reduction with benzoyl peroxide 5% gel and a 63% reduction with clindamycin. AzA 15% gel was well-tolerated. In addition, a 1-year European observational study conducted by dermatologists in private practice evaluated the safety and efficacy of AzA 15% gel used as monotherapy or in combination with other agents in more than 1200 patients with acne. Most physicians (81.9%) described an improvement in patients' symptoms after an average of 34.6 days, and 93.9% of physicians reported patient improvement after an average of 73.1 days. Both physicians and patients assessed AzA 15% gel to be effective with 74% of patients being "very satisfied" at the end of therapy. AzA 15% gel was considered "well-tolerated" or "very well-tolerated" by 95.7% of patients. The majority of patients were more satisfied with AzA than with previous therapies. AzA 15% gel represents a new therapeutic option for the treatment of acne vulgaris.

Investigator-reported efficacy of azelaic acid foam 15% in patients with papulopustular rosacea: secondary efficacy outcomes from a randomized, controlled, double-blind, phase 3 trial.

PubMed

Solomon, James A; Tyring, Stephen; Staedtler, Gerald; Sand, Meike; Nkulikiyinka, Richard; Shakery, Kaweh

2016-09-01

Papulopustular rosacea (PPR) is characterized by centrofacial papules and pustules commonly associated with erythema. To compare investigator-reported efficacy outcomes for azelaic acid (AzA) foam 15% versus vehicle foam in PPR, a randomized, vehicle-controlled, double-blind phase 3 clinical trial was conducted at 48 US sites. Participants received AzA foam or vehicle foam for 12 weeks. Secondary efficacy outcomes included change in inflammatory lesion count (ILC), therapeutic response rate according to investigator global assessment (IGA), and change in erythema rating. This study was comprised of 961 participants with PPR. The results support the therapeutic superiority of AzA foam over vehicle foam.

Synthesis of (azelaic-co-dodecanedioic) polyanhydride by microwave technique

NASA Astrophysics Data System (ADS)

Gutiérrez, M.; Sierra, C.; Acevedo Morantes, M.; Herrera, A. P.

2016-02-01

A polyanhydride was synthesized through microwave radiation using azelaic acid and dodecanedioic dicarboxylic acid at concentrations of 75:25, 50:50, and 25:75%w/w with acetic anhydride as crosslinking agent. Polymerization was carried out during 3 and 5 minutes. The copolymer with the highest molecular weight was selected using the intrinsic viscometry technique and by Huggin/Kraemer and Solomon/Ciuta methods. Based on these measurements, the 50:50 copolymer was selected with a polymerization time of 3 minutes in the microwave. This sample displayed the highest intrinsic viscosity (41.82cm3/g), demonstrating the relevance of the microwave technique for the synthesis of biopolymers.

Azelaic acid foam 15% in the treatment of papulopustular rosacea: a randomized, double-blind, vehicle-controlled study.

PubMed

Draelos, Zoe Diana; Elewski, Boni; Staedtler, Gerald; Havlickova, Blanka

2013-12-01

Rosacea is a common chronic inflammatory skin disease that primarily affects facial skin. Its etiology is unknown, and currently there is no cure. Rosacea can be associated with severe symptoms, including transient erythema (flushing), nontransient erythema, papules, pustules, and telangiectases, leading to substantial discomfort and an unattractive appearance. This randomized, double-blind, vehicle-controlled, multicenter, parallel-group study conducted over 12 weeks with a 4-week follow-up period evaluated the efficacy and safety of a new formulation of azelaic acid (AzA) foam in a 15% concentration compared to vehicle alone in patients with papulopustular rosacea (PPR). Primary efficacy variables assessed were investigator global assessment (IGA) dichotomized into success and failure, and nominal change in inflammatory lesion count from baseline to end of treatment. Results indicated that the new foam formulation of AzA is effective and well-tolerated in a population of patients with PPR. Although no single formulation is appropriate for all patients, the development of a new foam formulation in addition to other available vehicles provides patients with options and allows health care providers to match the needs as well as preferences of individual patients and skin types with appropriate delivery modalities.

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid.

PubMed

Al-Amiery, Ahmed A; Binti Kassim, Fatin A; Kadhum, Abdul Amir H; Mohamad, Abu Bakar

2016-01-22

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10(-3) M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir's adsorption isotherm. The effect of te perature on corrosion behavior in the presence of 5 × 10(-3) M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

NASA Astrophysics Data System (ADS)

Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

2016-01-01

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10-3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10-3 M inhibitor was studied in the temperature range of 30-60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl.

Synthesis and characterization of a novel eco-friendly corrosion inhibition for mild steel in 1 M hydrochloric acid

PubMed Central

Al-Amiery, Ahmed A.; Binti Kassim, Fatin A.; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar

2016-01-01

The acid corrosion inhibition process of mild steel in 1 M HCl by azelaic acid dihydrazide has been investigated using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, open circuit potential (OCP) and electrochemical frequency modulation (EFM). Azelaic acid dihydrazide was synthesized, and its chemical structure was elucidated and confirmed using spectroscopic techniques (infrared, nuclear magnetic resonance and mass spectroscopy). Potentiodynamic polarization studies indicate that azelaic acid dihydrazide is a mixed-type inhibitor. The inhibition efficiency increases with increased inhibitor concentration and reaches its maximum of 93% at 5 × 10−3 M. The adsorption of the inhibitor on a mild steel surface obeys Langmuir’s adsorption isotherm. The effect of temperature on corrosion behavior in the presence of 5 × 10−3 M inhibitor was studied in the temperature range of 30–60 °C. The results indicated that inhibition efficiencies were enhanced with an increase in concentration of inhibitor and decreased with a rise in temperature. To inspect the surface morphology of inhibitor film on the mild steel surface, scanning electron microscopy (SEM) was used before and after immersion in 1.0 M HCl. PMID:26795066

Molecular Recognition of Azelaic Acid and Related Molecules with DNA Polymerase I Investigated by Molecular Modeling Calculations.

PubMed

Shawon, Jakaria; Khan, Akib Mahmud; Rahman, Adhip; Hoque, Mohammad Mazharol; Khan, Mohammad Abdul Kader; Sarwar, Mohammed G; Halim, Mohammad A

2016-10-01

Molecular recognition has central role on the development of rational drug design. Binding affinity and interactions are two key components which aid to understand the molecular recognition in drug-receptor complex and crucial for structure-based drug design in medicinal chemistry. Herein, we report the binding affinity and the nonbonding interactions of azelaic acid and related compounds with the receptor DNA polymerase I (2KFN). Quantum mechanical calculation was employed to optimize the modified drugs using B3LYP/6-31G(d,p) level of theory. Charge distribution, dipole moment and thermodynamic properties such as electronic energy, enthalpy and free energy of these optimized drugs are also explored to evaluate how modifications impact the drug properties. Molecular docking calculation was performed to evaluate the binding affinity and nonbonding interactions between designed molecules and the receptor protein. We notice that all modified drugs are thermodynamically more stable and some of them are more chemically reactive than the unmodified drug. Promise in enhancing hydrogen bonds is found in case of fluorine-directed modifications as well as in the addition of trifluoroacetyl group. Fluorine participates in forming fluorine bonds and also stimulates alkyl, pi-alkyl interactions in some drugs. Designed drugs revealed increased binding affinity toward 2KFN. A1, A2 and A3 showed binding affinities of -8.7, -8.6 and -7.9 kcal/mol, respectively against 2KFN compared to the binding affinity -6.7 kcal/mol of the parent drug. Significant interactions observed between the drugs and Thr358 and Asp355 residues of 2KFN. Moreover, designed drugs demonstrated improved pharmacokinetic properties. This study disclosed that 9-octadecenoic acid and drugs containing trifluoroacetyl and trifluoromethyl groups are the best 2KFN inhibitors. Overall, these results can be useful for the design of new potential candidates against DNA polymerase I.

A multicenter study of topical azelaic acid 15% gel in combination with oral doxycycline as initial therapy and azelaic acid 15% gel as maintenance monotherapy.

PubMed

Thiboutot, Diane M; Fleischer, Alan B; Del Rosso, James Q; Rich, Phoebe

2009-07-01

This two-phase, multicenter study was undertaken to examine the safety and efficacy of combination therapy with oral doxycycline and topical azelaic acid (AzA) 15% gel in moderate-to-severe papulopustular rosacea and to determine the effect of subsequent maintenance monotherapy with AzA 15% gel alone. In the initial open-label, non-randomized phase of the study, subjects (n=172) received topical AzA 15% gel and oral doxycycline (100 mg), both twice daily, for < or = 12 weeks. In the second, double-blind study phase, subjects who had initially undergone at least four weeks of combination treatment in phase 1 and who achieved > or = 75% inflammatory lesion count reduction (n=136) were randomized to receive either AzA 15% gel or its vehicle twice daily for an additional 24 weeks. Assessments of efficacy were obtained at four-week intervals throughout both phases of the study and included change in inflammatory lesion count, investigator global assessment (IGA) of rosacea severity, and separate assessments of erythema and telangiectasia severity. At the last visit for each phase of the study, the investigator and participant each rated overall improvement, with the participant rating cosmetic acceptability and the investigator rating treatment as "success" or "failure" based on IGA score. During the second phase of the trial, the rate of relapse -- defined as either a 50% deterioration in the lesion count improvement from phase 1, an increase in erythema intolerable to the subject or maintenance therapy failure as judged by the investigator and/or the subject -- was obtained. Safety assessments were conducted for both phases of the study and included analysis of adverse events (AEs) and a rating of cutaneous tolerability by the subject. By week 12 of the open-label phase of the study, 81.4% of subjects had reached a 75% or greater reduction in inflammatory lesion count, and 64% of patients achieved treatment success. During the second study phase (maintenance phase

Glycolic Acid Peels/Azelaic Acid 20% Cream Combination and Low Potency Triple Combination Lead to Similar Reduction in Melasma Severity in Ethnic Skin: Results of a Randomized Controlled Study

PubMed Central

Mahajan, Rahul; Kanwar, Amrinder Jit; Parsad, Davinder; Kumaran, Muthu Sendhil; Sharma, Reena

2015-01-01

Background: Numerous therapeutic options have been tried in the management of melasma. Aims and Objectives: This prospective randomized study was planned to assess the efficacy of low potency triple combination (TC) cream (TC-hydroquinone 2%/tretinoin 0.05%/fluocinolone 0.01%) versus glycolic acid (GA) peels/azelaic acid (AA) 20% cream (GA/AA) combination in melasma. Materials and Methods: Forty patients with melasma were recruited into this study and randomized into two groups. Group A consisting 20 patients received TC cream once a day for night time application for 3 months. Group B comprising of 20 patients received GA/AA 20% cream combination for 3 months. The disease severity was monitored with digital photography, melasma area and severity index (MASI) score, which was calculated at baseline, 6 weeks and 12 weeks, and visual analog scale (VAS) score, which was calculated at baseline and 12 weeks. Results: Of 40 patients, 38 were completed the study. A significant reduction in MASI and VAS was recorded after 6 weeks and 12 weeks of treatment in both groups A and B (P = 0.001). However, there was no significant difference in the mean MASI scores between the two groups at baseline, 6 weeks and 12 weeks. Similarly, there was no difference in the mean VAS scores between the two groups at baseline and 12 weeks. Four patients in group A and 3 in group B experienced adverse effects such as irritation, dryness, and photosensitivity. Conclusion: Both low potency TC cream and GA/AA 20% cream combination are effective in treating melasma among Indian patients. PMID:25814702

Glycolic Acid peels/azelaic Acid 20% cream combination and low potency triple combination lead to similar reduction in melasma severity in ethnic skin: results of a randomized controlled study.

PubMed

Mahajan, Rahul; Kanwar, Amrinder Jit; Parsad, Davinder; Kumaran, Muthu Sendhil; Sharma, Reena

2015-01-01

Numerous therapeutic options have been tried in the management of melasma. This prospective randomized study was planned to assess the efficacy of low potency triple combination (TC) cream (TC-hydroquinone 2%/tretinoin 0.05%/fluocinolone 0.01%) versus glycolic acid (GA) peels/azelaic acid (AA) 20% cream (GA/AA) combination in melasma. Forty patients with melasma were recruited into this study and randomized into two groups. Group A consisting 20 patients received TC cream once a day for night time application for 3 months. Group B comprising of 20 patients received GA/AA 20% cream combination for 3 months. The disease severity was monitored with digital photography, melasma area and severity index (MASI) score, which was calculated at baseline, 6 weeks and 12 weeks, and visual analog scale (VAS) score, which was calculated at baseline and 12 weeks. Of 40 patients, 38 were completed the study. A significant reduction in MASI and VAS was recorded after 6 weeks and 12 weeks of treatment in both groups A and B (P = 0.001). However, there was no significant difference in the mean MASI scores between the two groups at baseline, 6 weeks and 12 weeks. Similarly, there was no difference in the mean VAS scores between the two groups at baseline and 12 weeks. Four patients in group A and 3 in group B experienced adverse effects such as irritation, dryness, and photosensitivity. Both low potency TC cream and GA/AA 20% cream combination are effective in treating melasma among Indian patients.

Efficacy and safety of azelaic acid (AzA) gel 15% in the treatment of post-inflammatory hyperpigmentation and acne: a 16-week, baseline-controlled study.

PubMed

Kircik, Leon H

2011-06-01

Although there are few differences in the incidence and pathophysiology of acne across various races and ethnicities, there is some evidence that black patients may have larger sebaceous glands and increased sebum production. Of greater clinical relevance, patients with darker skin types are at increased risk for the development of post-inflammatory hyperpigmentation (PIH), which some find as or more troubling than acne itself. This common and bothersome sequelum of acne can be difficult to manage in this population. Topical azelaic acid gel is recognized to have anti-tyrosinase activity, suggesting it may be a suitable treatment option for mild-to-moderate acne with associated moderate-to-severe PIH. This pilot study demonstrates the efficacy of topical AzA gel 15% when applied twice daily for the reduction of both acne and PIH. J

Gene expression profile of high-fat diet-fed C57BL/6J mice: in search of potential role of azelaic acid.

PubMed

Muthulakshmi, Shanmugam; Chakrabarti, Alok K; Mukherjee, Sanjay

2015-03-01

High-fat diet (HFD) elevates circulatory fatty acids and influences glucose and fat metabolism. Azelaic acid (AzA), a naturally occurring α,ω-dicarboxylic acid in wheat, rye, barley, oat seeds and sorghum, has been reported to exert antidiabetic effects in HFD-induced type 2 diabetes mellitus (T2DM) C57BL/6J mice. The present study was undertaken to identify the genes that are differentially modulated by treatment with AzA in HFD-fed mice. Mice were fed HFD for 10 weeks and subjected to intragastric administration of 80 mg/kg body weight (BW) of AzA daily along with HFD from 11 to 15 weeks. Lipid profile, adipokines and cytokines were examined in the plasma/liver of mice. Whole genome profiling was performed in the liver of mice using microarray and validated by qRT-PCR, Western blot and immunohistochemical analyses. HFD intake resulted in significantly elevated lipids (except high-density lipoproteins), resistin, tumour necrosis factor alpha and interleukin-6 with marked reduction in adiponectin. Administration of AzA to HFD-fed mice significantly restored the lipids, adipokines and cytokines to near normal. Transcript profiling revealed that HFD intake activated the genes involved in stress response, cell cycle regulation and apoptosis. Treatment with AzA caused increased expression of genes involved in reactive oxygen species (ROS) scavenging, receptor-mediated signalling, transcription, protein modification and insulin signal transduction. AzA activates insulin signal molecules leading to insulin sensitivity. The ability of AzA to modulate the expression of these genes supports the notion that AzA is a promising drug candidate for the treatment of insulin resistance associated with T2DM.

Raman spectroscopic study of the conformation of dicarboxylic acid salts in aqueous solutions

NASA Astrophysics Data System (ADS)

Fukushima, Kunio; Watanabe, Toshiaki; Umemura, Matome

1986-08-01

It is already known that the molecules of long chain monocarboxylic acid salts have a tendency to form micelles in aqueous solutions, the molecular chain taking the all- trans zigzag structure. However it is considered difficult for dicarboxylic acid salts to adopt the same structure as the monocarboxylic acid salts as they have two carboxyl groups, one on each end of the molecular chain. Therefore, a special structure is expected to exist for dicarboxylic acid salts in aqueous solution. In order to examine this, Raman spectra of suberic acid salt and azelaic acid salt in aqueous solution were measured and the normal vibrational calculation carried out, showing that dicarboxylic acid salts have a helical structure in aqueous solution.

Cathelicidin, kallikrein 5, and serine protease activity is inhibited during treatment of rosacea with azelaic acid 15% gel

PubMed Central

Coda, Alvin B.; Hata, Tissa; Miller, Jeremiah; Audish, David; Kotol, Paul; Two, Aimee; Shafiq, Faiza; Yamasaki, Kenshi; Harper, Julie C.; Del Rosso, James Q.; Gallo, Richard L.

2014-01-01

Background Excess cathelicidin and kallikrein 5 (KLK5) have been hypothesized to play a role in the pathophysiology of rosacea. Objective We sought to evaluate the effects of azelaic acid (AzA) on these elements of the innate immune system. Methods Gene expression and protease activity were measured in laboratory models and patients with rosacea during a 16-week multicenter, prospective, open-label study of 15% AzA gel. Results AzA directly inhibited KLK5 in cultured keratinocytes and gene expression of KLK5, Toll-like receptor-2, and cathelicidin in mouse skin. Patients with rosacea showed reduction in cathelicidin and KLK5 messenger RNA after treatment with AzA gel. Subjects without rosacea had lower serine protease activity (SPA) than patients with rosacea. Distinct subsets of patients with rosacea who had high and low baseline SPA were identified, and patients with high baseline exhibited a statistically significant reduction of SPA with 15% AzA gel treatment. Limitations Study size was insufficient to predict clinical efficacy based on the innate immune response to AzA. Conclusions These results show that cathelicidin and KLK5 decrease in association with AZA exposure. Our observations suggest a new mechanism of action for AzA and that SPA may be a useful biomarker for disease activity. PMID:23871720

Efficacy of azelaic acid on hepatic key enzymes of carbohydrate metabolism in high fat diet induced type 2 diabetic mice.

PubMed

Muthulakshmi, Shanmugam; Saravanan, Ramalingam

2013-06-01

Azelaic acid (AzA), a C9 linear α,ω-dicarboxylic acid, is found in whole grains namely wheat, rye, barley, oat seeds and sorghum. The study was performed to investigate whether AzA exerts beneficial effect on hepatic key enzymes of carbohydrate metabolism in high fat diet (HFD) induced type 2 diabetic C57BL/6J mice. C57BL/6J mice were fed high fat diet for 10 weeks and subjected to intragastric administration of various doses (20 mg, 40 mg and 80 mg/kg BW) of AzA daily for the subsequent 5 weeks. Rosiglitazone (RSG) was used as reference drug. Body weight, food intake, plasma glucose, plasma insulin, blood haemoglobin (Hb), blood glycosylated haemoglobin (HbA1c), liver glycolytic enzyme (hexokinase), hepatic shunt enzyme (glucose-6-phosphate dehydrogenase), gluconeogenic enzymes(glucose-6-phosphatase and fructose-1,6-bisphosphatase), liver glycogen, plasma and liver triglycerides were examined in mice fed with normal standard diet (NC), high fat diet (HFD), HFD with AzA (HFD + AzA) and HFD with rosiglitazone (HFD + RSG). Among the three doses, 80 mg/kg BW of AzA was able to positively regulate plasma glucose, insulin, blood HbA1c and haemoglobin levels by significantly increasing the activity of hexokinase and glucose-6-phosphate dehydrogenase and significantly decreasing the activity of glucose-6-phosphatase and fructose-1,6-bisphosphatase thereby increasing the glycogen content in the liver. From this study, we put forward that AzA could significantly restore the levels of plasma glucose, insulin, HbA1c, Hb, liver glycogen and carbohydrate metabolic key enzymes to near normal in diabetic mice and hence, AzA may be useful as a biomaterial in the development of therapeutic agents against high fat diet induced T2DM. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

A phase 3 randomized, double-blind, vehicle-controlled trial of azelaic acid foam 15% in the treatment of papulopustular rosacea.

PubMed

Draelos, Zoe Diana; Elewski, Boni E; Harper, Julie C; Sand, Meike; Staedtler, Gerald; Nkulikiyinka, Richard; Shakery, Kaweh

2015-07-01

Rosacea is a chronic relapsing skin disorder primarily affecting the face. Although its etiology is not well defined, rosacea is associated with immune dysregulation and inflammation potentiated by external factors. These manifestations lead to skin sensitivity and impaired quality of life. Azelaic acid (AzA) is approved for the treatment of rosacea in a 15% gel formulation. This phase 3 study evaluated the efficacy and safety of AzA in a 15% foam formulation for the treatment of papulopustular rosacea (PPR). Coprimary efficacy end points were treatment success according to investigator global assessment (IGA) and the nominal change in inflammatory lesion count (ILC) from baseline to the end of treatment (EoT). Adverse events (AEs) were evaluated as a measure of safety. The IGA success rate at EoT was significantly greater in the AzA foam group versus vehicle (P<.001; Cochran-Mantel-Haenszel test). Likewise, nominal ILC change at EoT in the AzA foam group showed a significantly greater decrease versus vehicle (P<.001; F test). Drug-related AEs were mainly mild to moderate, cutaneous, and local. Overall, the study results support the efficacy and safety of twice-daily AzA foam 15% in patients with PPR.

Combination of azelaic acid 5% and clindamycin 2% for the treatment of acne vulgaris.

PubMed

Pazoki-Toroudi, Hamidreza; Nilforoushzadeh, Mohamad Ali; Ajami, Marjan; Jaffary, Fariba; Aboutaleb, Nahid; Nassiri-Kashani, Mansour; Firooz, Alireza

2011-12-01

Acne vulgaris, an inflammatory skin disease with different clinical appearances, is a common problem in most adolescents. It seems that using combinations of topical agents can decrease resistance to the treatment and improve the efficacy. Therefore, we evaluated the effects of azelaic acid (AA) 5% and clindamycin (Clin) 2% combination (AA-Clin) on mild-to-moderate acne vulgaris. The efficacy and safety of 12-week treatment with AA-Clin in patients with mild-to-moderate facial acne vulgaris were evaluated by a multicenter, randomized, and double-blind study. A total of 88 male and 62 female patients were randomly assigned to one of these treatments: AA 5%, Clin 2%, and combination of them. Every 4 weeks, total inflammatory and noninflammatory lesions were counted, acne severity index (ASI) was calculated, and patient satisfaction was recorded. Treatment for 12 weeks with combination gel significantly reduced the total lesion number compared with baseline (p < 0.01), as well as Clin 2% or AA 5% treatment groups (p < 0.05 or p < 0.01). The percentage of reduction in ASI in combination treated group (64.16 ± 6.01) was significantly more than those in the Clin 2% (47.73 ± 6.62, p < 0.05) and 5% AA (32.46 ± 5.27, p < 0.01) groups after 12 weeks. Among the patients in the AA-Clin group, 75.86% of males were satisfied or very satisfied and 85.71% of females were satisfied or very satisfied. This trend was significant in comparison to the number of patients who were satisfied with AA 5% or Clin 2% treatment (p < 0.01). Seven patients in AA-Clin group (incidence = 22%) showed adverse effects that were not statistically significant compared to treatment with individual active ingredients. The profound reduction in lesion count and ASI by combination therapy with AA-Clin gel in comparison to individual treatment with 5% AA or Clin 2% suggested the combination formula as an effective alternative in treatment of acne vulgaris.

Cathelicidin, kallikrein 5, and serine protease activity is inhibited during treatment of rosacea with azelaic acid 15% gel.

PubMed

Coda, Alvin B; Hata, Tissa; Miller, Jeremiah; Audish, David; Kotol, Paul; Two, Aimee; Shafiq, Faiza; Yamasaki, Kenshi; Harper, Julie C; Del Rosso, James Q; Gallo, Richard L

2013-10-01

Excess cathelicidin and kallikrein 5 (KLK5) have been hypothesized to play a role in the pathophysiology of rosacea. We sought to evaluate the effects of azelaic acid (AzA) on these elements of the innate immune system. Gene expression and protease activity were measured in laboratory models and patients with rosacea during a 16-week multicenter, prospective, open-label study of 15% AzA gel. AzA directly inhibited KLK5 in cultured keratinocytes and gene expression of KLK5, Toll-like receptor-2, and cathelicidin in mouse skin. Patients with rosacea showed reduction in cathelicidin and KLK5 messenger RNA after treatment with AzA gel. Subjects without rosacea had lower serine protease activity (SPA) than patients with rosacea. Distinct subsets of patients with rosacea who had high and low baseline SPA were identified, and patients with high baseline exhibited a statistically significant reduction of SPA with 15% AzA gel treatment. Study size was insufficient to predict clinical efficacy based on the innate immune response to AzA. These results show that cathelicidin and KLK5 decrease in association with AZA exposure. Our observations suggest a new mechanism of action for AzA and that SPA may be a useful biomarker for disease activity. Copyright © 2013 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Identification of dicarboxylic acids and aldehydes of PM10 and PM2.5 aerosols in Nanjing, China

NASA Astrophysics Data System (ADS)

Wang, Gehui; Niu, Sulian; Liu, Caie; Wang, Liansheng

In this study aerosol samples of PM10 and PM2.5 collected from 18 February 2001 to 1 May 2001 in Nanjing, China were analyzed for their water-soluble organic compounds. A series of homologous dicarboxylic acids (C 2-10) and two kinds of aldehydes (methylglyoxal and 2-oxo-malonaldehyde) were detected by GC and GC/MS. Among the identified compounds, the concentration of oxalic acid was the highest at all the five sites, which ranged from 178 to 1423 ng/m 3. The second highest concentration of dicarboxylic acids were malonic and succinic acids, which ranged from 26.9 to 243 ng/m 3. Higher level of azelaic acid was also observed, of which the maximum was 301 ng/m 3. As the highest fraction of dicarboxylic acids, oxalic acid comprised from 28% to 86% of total dicarboxylic acids in PM10 and from 41% to 65% of total dicarboxylic acids in PM2.5. The dicarboxylic acids (C 2, C 3, C 4) together accounted for 38-95% of total dicarboxylic acids in PM10 and 59-87% of dicarboxylic acids in PM2.5. In this study, the total dicarboxylic acids accounted for 2.8-7.9% of total organic carbon (TOC) of water-soluble matters for PM10 and 3.4-11.8% of TOC for PM2.5. All dicarboxylic acids detected in this study together accounted for about 1% of particle mass. The concentration of azelaic acid was higher at one site than others, which may be resulted from higher level of volatile fat used for cooking. The amounts of dicarboxyic acids (C 2,3,4,9) and 2-oxo-malonaldehyde of PM2.5 were higher in winter and lower in spring. Compared with other major metropolitans in the world, the level of oxalic acid concentration of Nanjing is much higher, which may be contributed to higher level of particle loadings, especially for fine particles.

Azelaic acid reduced senescence-like phenotype in photo-irradiated human dermal fibroblasts: possible implication of PPARγ.

PubMed

Briganti, Stefania; Flori, Enrica; Mastrofrancesco, Arianna; Kovacs, Daniela; Camera, Emanuela; Ludovici, Matteo; Cardinali, Giorgia; Picardo, Mauro

2013-01-01

Azelaic acid (AzA) has been used for the treatment for inflammatory skin diseases, such as acne and rosacea. Interestingly, an improvement in skin texture has been observed after long-time treatment with AzA. We previously unrevealed that anti-inflammatory activity of AzA involves a specific activation of PPARγ, a nuclear receptor that plays a relevant role in inflammation and even in ageing processes. As rosacea has been considered as a photo-aggravated disease, we investigated the ability of AzA to counteract stress-induced premature cell senescence (SIPS). We employed a SIPS model based on single exposure of human dermal fibroblasts (HDFs) to UVA and 8-methoxypsoralen (PUVA), previously reported to activate a senescence-like phenotype, including long-term growth arrest, flattened morphology and increased synthesis of matrix metalloproteinases (MMPs) and senescence-associated β-galactosidase (SA-β-gal). We found that PUVA-treated HDFs grown in the presence of AzA maintained their morphology and reduced MMP-1 release and SA-β-galactosidase-positive cells. Moreover, AzA induced a reduction in ROS generation, an up-modulation of antioxidant enzymes and a decrease in cell membrane lipid damages in PUVA-treated HDFs. Further evidences of AzA anti-senescence effect were repression of p53 and p21, increase in type I pro-collagen and abrogation of the enhanced expression of growth factors, such as HGF and SCF. Interestingly, PUVA-SIPS showed a decreased activation of PPARγ and AzA counteracted this effect, suggesting that AzA effect involves PPARγ modulation. All together these data showed that AzA interferes with PUVA-induced senescence-like phenotype and its ability to activate PPAR-γ provides relevant insights into the anti-senescence mechanism. © 2013 John Wiley & Sons A/S.

The co-drug of conjugated hydroquinone and azelaic acid to enhance topical skin targeting and decrease penetration through the skin.

PubMed

Hsieh, Pei-Wen; Al-Suwayeh, Saleh A; Fang, Chia-Lang; Lin, Chwan-Fwu; Chen, Chun-Che; Fang, Jia-You

2012-06-01

A co-drug of hydroquinone (HQ) and azelaic acid (AA), bis(4-hydroxyphenyl)nonanedioate (BHN), was synthesized and investigated as a topical prodrug with the aim of improving the dermal delivery of the parent drugs. Physicochemical parameters were ascertained, and the enzymatic hydrolysis was examined. Skin permeation of HQ, AA, and BHN was studied by determining the skin deposition and flux across nude mouse skin under equivalent doses with the same thermodynamic activity. The partition coefficient (log P) of the co-drug increased by up to 5.0 with HQ and AA conjugation, which had respective log P values of 0.5 and 1.4. In the skin absorption experiment, BHN in ethanol/pH 7 buffer resulted in a 2-fold enhancement of skin deposition compared to both HQ and AA. With permeation using polyethylene glycol 400/pH 7 buffer as the vehicle, the co-drug, respectively, exhibited 8.1- and 1.4-fold enhancements of skin uptake compared to HQ and AA alone. The transdermal flux from BHN was negligible compared to those with HQ and AA treatments. The results of a preliminary safety evaluation showed no signs of stratum corneum disruption or erythema by BHN application within 24h. The co-drug approach provides a viable option for the treatment of skin hyperpigmentation of HQ and AA. Copyright © 2012 Elsevier B.V. All rights reserved.

The ultrasound-assisted oxidative scission of monoenic fatty acids by ruthenium tetroxide catalysis: influence of the mixture of solvents.

PubMed

Rup, Sandrine; Zimmermann, François; Meux, Eric; Schneider, Michel; Sindt, Michele; Oget, Nicolas

2009-02-01

Carboxylic acids and diacids were synthesized from monoenic fatty acids by using RuO4 catalysis, under ultrasonic irradiation, in various mixtures of solvents. Ultrasound associated with Aliquat 336 have promoted in water, the quantitative oxidative cleavage of the CH=CH bond of oleic acid. A design of experiment (DOE) shows that the optimal mixture of solvents (H2O/MeCN, ratio 1/1, 2.2% RuCl3/4.1 eq. NaIO4) gives 81% azelaic acid and 97% pelargonic acid. With the binary heterogeneous mixture H2O/AcOEt, the oxidation of the oleic acid leads to a third product, the alpha-dione 9,10-dioxostearic acid.

Study on Dicarboxylic Acids in Aerosol Samples with Capillary Electrophoresis

PubMed Central

Adler, Heidi; Sirén, Heli

2014-01-01

The research was performed to study the simultaneous detection of a homologous series of α, ω-dicarboxylic acids (C2–C10), oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic, and sebacic acids, with capillary electrophoresis using indirect UV detection. Good separation efficiency in 2,6-pyridinedicarboxylic acid as background electrolyte modified with myristyl trimethyl ammonium bromide was obtained. The dicarboxylic acids were ionised and separated within five minutes. For the study, authentic samples were collected onto dry cellulose membrane filters of a cascade impactor (12 stages) from outdoor spring aerosols in an urban area. Hot water and ultrasonication extraction methods were used to isolate the acids from membrane filters. Due to the low concentrations of acids in the aerosols, the extracts were concentrated with solid-phase extraction (SPE) before determination. The enrichment of the carboxylic acids was between 86 and 134% with sample pretreatment followed by 100-time increase by preparation of the sample to 50 μL. Inaccuracy was optimised for all the sample processing steps. The aerosols contained dicarboxylic acids C2–C10. Then, mostly they contained C2, C5, and C10. Only one sample contained succinic acid. In the study, the concentrations of the acids in aerosols were lower than 10 ng/m3. PMID:24729915

Secondary formation of oxalic acid and related organic species from biogenic sources in a larch forest at the northern slope of Mt. Fuji

NASA Astrophysics Data System (ADS)

Mochizuki, Tomoki; Kawamura, Kimitaka; Miyazaki, Yuzo; Wada, Ryuichi; Takahashi, Yoshiyuki; Saigusa, Nobuko; Tani, Akira

2017-10-01

To better understand the formation of water-soluble organic aerosols in the forest atmosphere, we measured low molecular weight (LMW) dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, unsaturated fatty acids (UFAs), and water-soluble organic carbon (WSOC) in aerosols from a Larix kaempferi forest located at the northern slope of Mt. Fuji, Japan, in summer 2012. Concentrations of dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, and WSOC showed maxima in daytime. Relative abundance of oxalic acid in LMW dicarboxylic acids was on average 52% and its average concentration was 214 ng m-3. We found that diurnal and temporal variations of oxalic acid are different from those of isoprene and α-pinene, whereas biogenic secondary organic aerosols (BSOAs) derived from isoprene and α-pinene showed similar variations with oxalic acid. The mass concentration ratios of oxalic acid/BSOAs were relatively constant, although a large variation in the concentrations of toluene that is an anthropogenic volatile organic compound was observed. These results suggest that formation of oxalic acid is associated with the oxidation of isoprene and α-pinene with O3 and other oxidants in the forest atmosphere. In addition, concentrations of UFAs were observed, for the first time, to decrease dramatically during daytime in the forest. Mass concentration ratios of azelaic acid to UFAs showed a positive correlation with O3, suggesting that UFAs are oxidized to yield azelaic acid, which may be further decomposed to oxalic acid in the forest atmosphere. We found that contributions of oxalic acid to WSOC are significantly high ranging from 3.7 to 9.7% (average 6.0%). This study demonstrates that forest ecosystem is an important source of oxalic acid and other dicarboxylic acids in the atmosphere.

Seasonal and longitudinal distributions of atmospheric water-soluble dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls over the North Pacific

NASA Astrophysics Data System (ADS)

Bikkina, Srinivas; Kawamura, Kimitaka; Imanishi, Katsuya; Boreddy, S. K. R.; Nojiri, Yukihiro

2015-05-01

In order to assess the seasonal variability of atmospheric abundances of dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls over the North Pacific and Sea of Japan, aerosol samples were collected along the longitudinal transacts during six cruises between Canada and Japan. The back trajectory analyses indicate that aerosol samples collected in winter and spring are influenced by the East Asian outflow, whereas summer and fall samples are associated with the pristine maritime air masses. Molecular distributions of water-soluble organics in winter and spring samples show the predominance of oxalic acid (C2) followed by succinic (C4) and malonic acids (C3). In contrast, summer and fall marine aerosols are characterized by the predominance of C3 over C4. Concentrations of dicarboxylic acids were higher over the Sea of Japan than the North Pacific. With a lack of continental outflow, higher concentrations during early summer are ascribed to atmospheric oxidation of organic precursors associated with high biological activity in the North Pacific. This interpretation is further supported by the high abundances of azelaic acid, which is a photochemical oxidation product of biogenic unsaturated fatty acids, over the Bering Sea in early summer when surface waters are characterized by high biological productivity. We found higher ratios of oxalic acid to pyruvic and glyoxylic acids (C2/Pyr and C2/ωC2) and glyoxal and methylglyoxal (C2/Gly and C2/MeGly) in summer and fall than in winter and spring, suggesting a production of C2 from the aqueous-phase oxidation of oceanic isoprene. In this study, dicarboxylic acids account for 0.7-38% of water-soluble organic carbon.

Protective effects of azelaic acid against high-fat diet-induced oxidative stress in liver, kidney and heart of C57BL/6J mice.

PubMed

Muthulakshmi, Shanmugam; Saravanan, Ramalingam

2013-05-01

Excess fat intake induces hyperinsulinaemia, increases nutrient uptake and lipid accumulation, amplifies ROS generation, establishes oxidative stress and morphological changes leading to tissue injury in the liver, kidney and heart of high-fat diet (HFD)-fed mice. The effect of azelaic acid (AzA), a C9 α,ω-dicarboxylic acid, against HFD-induced oxidative stress was investigated by assaying the activities and levels of antioxidants and oxidative stress markers in the liver, kidney and heart of C57BL/6J mice. Mice were segregated into two groups, one fed standard diet (NC) and the other fed high-fat diet (HFD) for 15 weeks. HFD-fed mice were subjected to intragastric administration of AzA (80 mg/kg BW)/RSG (10 mg/kg BW) during 11-15 weeks. Glucose, insulin, triglycerides, hepatic and nephritic markers were analysed in the plasma and the activity of enzymatic, non-enzymatic antioxidants and lipid peroxidation markers were examined in the plasma/erythrocytes, liver, kidney and heart of normal and experimental mice. We inferred significant decrease in enzymatic and non-enzymatic antioxidants along with significant increase in glucose, insulin, hepatic and nephritic markers, triglycerides and lipid peroxidation markers in HFD-fed mice. Administration of AzA could positively restore the levels of plasma glucose, insulin, triglycerides, hepatic and nephritic markers to near normal. AzA increased the levels of enzymatic and nonenzymatic antioxidants with significant reduction in the levels of lipid peroxidation markers. Histopathological examination of liver, kidney and heart substantiated these results. Hence, we put forward that AzA could counteract the potential injurious effects of HFD-induced oxidative stress in C57BL/6J mice.

Molecular distribution, seasonal variation, chemical transformation and sources of dicarboxylic acids and related compounds in atmospheric aerosols at remote marine Gosan site, Jeju Island

NASA Astrophysics Data System (ADS)

Kundu, S.; Kawamura, K.; Lee, M.

2009-12-01

: A homologous series of C2-C12 α, ω-dicarboxylic acids, ω-oxocarboxylic acids (C2-C9), pyruvic acid and α-dicarbonyls (C2-C3) were detected in atmospheric aerosols collected between April 2003 and April 2004 from remote marine Gosan site (33°29‧ N, 126°16‧ E) located in Jeju Island, South Korea. They were determined using a GC-FID and GC/MS. Total diacid concentration ranged from 130 to 1911 ng m-3 (av. 642 ng m-3), whereas total oxoacid concentration ranged from 7 to 155 ng m-3 (av. 43 ng m-3), and pyruvic acid and α-dicarbonyls ranged from 0.5 to 15 ng m-3 (av. 5 ng m-3) and 2-108 ng m-3 (av. 17.3 ng m-3), respectively. Oxalic (C2) acid was the most abundant in all seasons followed by malonic (C3) or succinic (C4) acid, and phthalic (Ph) acid. The concentration of diacids decreased with an increase in carbon number except for azelaic (C9) acid, which was more abundant than suberic (C8) acid. Glyoxylic acid was predominant ω-oxoacid contributing to 92% of total ω-oxoacid. Total diacids, oxoacids and dicarbonyls showed maximum concentrations in spring and occasionally in winter, while minimum concentrations were observed in summer. Air mass trajectory analysis suggests that either spring or winter maxima can be explained by strong continental outflow associated with cold front passages, while summer minima are associated with warm southerly flows, which transport clean marine air from low latitudes to Jeju Island. The comparison between total diacid concentration level of this study and other study results of urban and remote sites of East Asia reveals that Gosan site is more heavily influenced by the continental outflow from China. The seasonal variation of malonic/succinic (C3/C4), malic/succinic (hC4/C4), fumaric/maleic (F/M), oxalic/pyruvic (C2/Py) and oxalic/Glyoxal (C2/Gly) ratios showed maxima in summer due to an enhanced photo-production and degradation of diacids and related compounds. Throughout all seasons C3/C4 ratio at Gosan site, located

Particulate organic acids in the atmosphere of Italian cities: Are they environmentally relevant?

NASA Astrophysics Data System (ADS)

Balducci, Catia; Cecinato, Angelo

2010-02-01

Mono- and dicarboxylic n-alkyl acids were extensively investigated in downtown Rome, Italy, and in Montelibretti, ˜30 km NE of the city, during 2005-2007. Congeners ranging from lauric to mellisic, and from succinic to α,ω-docosanedioic acids were evaluated as well as phthalic, palmitoleic and oleic acids, by solvent extraction of airborne particulates followed by derivatization with propanol in the presence of boron trifluoride, and gas chromatographic-mass spectrometric analysis. Shorter measurements were made in Milan, in Taranto, at suburban and rural sites of Italy, and in the polar regions, from 1996 to 2005. The predominance of palmitic and stearic acids observed elsewhere was confirmed, and the behaviour of azelaic and phthalic acids resulted strongly dependent upon the year season. In the urban sites, among the long-chain compounds, the lignoceric acid was usually the most abundant, while the cerotic, montanic and mellisic homologues cumulatively never exceeded 8% of the total. Unlike other contaminants, the concentrations of organic acids remained fairly invariant over the last decade, suggesting that more attention must be paid to them in the future.

Acute Toxicity of a Number of Chemicals of Interest to the Air Force

DTIC Science & Technology

1979-03-01

Acid Azelaic Acid Dimer Acid N-Benzyl-3, 7-Dioctyl Phenothiazine Phenothiazine Dioctyl Phenothiazine Sebacic Acid ...liquid) 1,4-dihydroxyanthraquinone (solid) Sulfurized 9-octadecenoic acid (liquid) Azelaic acid (solid) Dimer acid (liquid) N-benzyl-3,7-dicotyl...dihydroxyanthra- Rat >5000 5000(0) Below Toxic quinone Sulfurized 9-octa- Rat >5000 5000(0) Below Toxic decenoic acid Azelaic acid Rat >5000

Latitudinal distributions of atmospheric dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls over the western North Pacific: Sources and formation pathways

NASA Astrophysics Data System (ADS)

Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo

2015-05-01

The present study aims to assess the molecular distributions of water-soluble dicarboxylic acids (diacids: C2-C12), oxocarboxylic acids (C2-C9), and α-dicarbonyls (glyoxal and methylglyoxal) in aerosols collected over the western North Pacific (WNP) during a summer cruise (August to September 2008). The measured water-soluble organics show pronounced latitudinal distributions with higher concentrations in the region of 30°N-45°N (average 63 ng m-3) than 10°N-30°N (18 ng m-3). Mass fraction of oxalic acid (C2) in total aliphatic diacids (ΣC2-C12) showed higher values (72 ± 10%) in lower latitude (10°N-30°N) than that (56 ± 16%) in higher latitude (30°N-45°N), suggesting a photochemical production of C2 due to an increased insolation over the tropical WNP. A similar trend was found in other diagnostic ratios such as oxalic to succinic (C2/C4) and oxalic to glyoxylic acid (C2/ωC2), which further corroborate an enhanced photochemical aging over the WNP. In addition, relative abundances of oxalic acid in total diacids showed a marked increase as a function of ambient temperature, supporting their photochemical production. Constantly low concentration ratios of adipic and phthalic acids relative to azelaic acid suggest a small contribution of anthropogenic sources and an importance of oceanic sources during the study period. Significant production of C2 through oxidation of biogenic volatile organic compounds emitted from the sea surface is also noteworthy, as inferred from the strong linear correlations among water-soluble organic carbon, methanesulphonic acid, and oxalic acid. Sea-to-air emission of unsaturated fatty acids also contributes to formation of diacids over the WNP.

Water soluble dicarboxylic acids and related compounds in Antarctic aerosols

NASA Astrophysics Data System (ADS)

Kawamura, Kimitaka; SeméRé, Richard; Imai, Yoshie; Fujii, Yoshiyuki; Hayashi, Masahiko

1996-08-01

Antarctic aerosols collected at Syowa Station were studied for water soluble organic compounds by employing a water extraction and dibutyl ester derivatization and using a capillary gas chromatography (GC) and GC/mass spectrometry (GC/MS). Total carbon and nitrogen were also determined. A homologous series of α,ω-dicarboxylic acids (C2-C11), ω-oxocarboxylic acids (C2-C9), and α-dicarbonyls (C2-C3) were detected, as well as pyruvic acid and aromatic (phthalic) diacid. Succinic (C4) or oxalic (C2) acid was found to be the dominant diacid species, followed by azelaic (C9), adipic (C6), or malonic (C3) acid. Concentration range of the total diacids was 5.9-88 ng m-3, with an average of 29 ng m-3. Highest concentrations were observed in the summer sample with a predominance of succinic acid (61.5 ng m-3), which comprised approximately 70% of the total diacids and accounted for 3.5% of total aerosol carbon (1020 ng m-3). The succinic acid (C4) is likely produced by photooxidation of 4-oxocarboxylic acids, which are present in the atmosphere as intermediates of the photooxidation of unsaturated fatty acids. These results indicate that the Antarctic organic aerosols originate from marine-derived lipids and are transformed largely by photochemical oxidations. ω-Oxocarboxylic acids (C2-C9, 0.36-3.0 ng m-3) also showed the highest concentration in the summer sample, again suggesting a secondary production in the atmosphere of the Antarctic and in the Southern Ocean.

Effect of 2 ppm ozone exposure on rat lung lipid fatty acids

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

Rabinowitz, J.L.; Bassett, D.J.

Based on in vitro studies, the initial damage to lung cells by ozone exposure is believed to result in part from the breakdown of lipid polyunsaturated fatty acids to aldehydes, ozonides, and peroxides. The present study measured lipid breakdown products in lungs isolated from rats pretreated with (1-/sup 14/C)acetate 12 h before exposure for 4 h to either air or 2 ppm ozone. Lipid fatty acid breakdown was indicated by a 112% increase in thiobarbituric acid-reactive substances on ozone exposure and by changes in chemical and radioactive measurements of mono- and dicarboxylic acids formed by treatment of lipid fractions withmore » hydrogen peroxide. Ozone exposure resulted in a 63% increase in recovery of short-chain fatty acids accounted for by increased recoveries of malonic acid by 37%, hexanoic acid by 47%, nonanoic acid by 118%, and azelaic acid by 107%. Recovery of glutaric acid was enhanced 15-fold by ozone exposure. Although decreases in tissue arachidonic acid could not be detected, oleic acid was significantly decreased by 36%. Recovery of radiolabel as short-chain fatty acids was increased by 65% on ozone exposure and was mainly accounted for by enhanced labeling of nonanoic and glutaric acid fractions. The failure to observe significant increases in /sup 14/C recovery in the other fractions suggested ozone-induced breakdown of unlabeled fatty acids. These results demonstrate the cleavage of unsaturated fatty acid double bonds following in vivo exposure of lungs to ozone. Breakdown of arachidonic and oleic acids was specifically identified by increased recoveries of glutaric and nonanoic acids, respectively.« less

Seasonal variations and source identification of selected organic acids associated with PM10 in the coastal area of Southeastern China

NASA Astrophysics Data System (ADS)

Wu, Shui-Ping; Schwab, James; Liu, Bi-Lian; Li, Tsung-Chang; Yuan, Chung-Shin

2015-03-01

PM10 aerosols from the coastal area of Southeastern China were collected from April 2010 to March 2011 and were measured for C2-C10 dicarboxylic acids, phthalic acids (Ph) and five fatty acids (palmitic, stearic, oleic, linoleic and elaidic acids). For all sites and seasons, molecular distributions of diacids were always characterized by a predominance of oxalic acid (C2), with a relative abundance of 68-87%, followed by malonic acid (C3) and by either succinic acid (C4) or phthalic acid (Ph). This observed molecular composition was different from that in Chinese megacities where Ph was significantly higher than C3 and C4 diacids, which was likely due to the less intensive traffic emissions in the coastal area. Seasonal means of total diacids ranged between 394 and 547 ng m- 3 at the coastal urban sites and between 163 and 245 ng m- 3 at off-island sites. These levels were much lower than those reported in Chinese megacities (668-1568 ng m- 3) and slightly lower than those in Jeju Island, Korea (464-744 ng m- 3) but higher than those in marine and continental background locations. In all seasons, saturated fatty acids were significantly higher than unsaturated fatty acids due to their greater photochemical stabilities in the atmosphere. Most organic acids showed higher levels in spring and winter and lower levels in summer and fall, which was likely due to the influence of transport and meteorology. The diagnostic ratios of malonic acid to succinic acid (C3/C4), adipic acid to azelaic acid (C6/C9) and phthalic acid to azelaic acid (Ph/C9) were significantly higher in summer than in winter. These diagnostic ratios in the sampled ambient aerosols were completely different from those in primary emissions, suggesting the importance of photochemical production - especially in summer. The diurnal variations of diacids and fatty acid as well as the diagnostic ratios are associated with higher solar radiation and anthropogenic activities during the daytime. Principal

Efficacy of topical azelaic acid (AzA) gel 15% plus oral doxycycline 40 mg versus metronidazole gel 1% plus oral doxycycline 40 mg in mild-to-moderate papulopustular rosacea.

PubMed

Del Rosso, James Q; Bruce, Suzanne; Jarratt, Michael; Menter, Alan; Staedtler, Gerald

2010-06-01

Rosacea is a leading reason why people seek the care of a dermatologist, accounting for nearly 7 million office visits annually. Pharmacologic treatments include both topical and oral medications, which are increasingly being used in combination, especially at the outset of therapy. This exploratory study assesses the safety, effectiveness and speed of onset of two common topical agents for the treatment of rosacea--azelaic acid gel (AzA) 15% and metronidazole gel 1%--used in conjunction with anti-inflammatory dose doxycycline (40 mg once daily). Men and women (n = 207) with mild-to-moderate papulopustular rosacea were enrolled and randomized to receive either AzA gel 15% twice daily plus doxycycline 40 mg once daily (AzA group) or metronidazole gel 1% once daily plus doxycycline 40 mg once daily (Metro group) for 12 weeks. Both regimens were safe, efficacious and well tolerated. Efficacy parameters revealed a possible trend toward greater and earlier benefit with the AzA-based regimen than with the metronidazole-based regimen. These findings warrant further investigation in a sufficiently powered study.

Topical Acne Treatments and Pregnancy

MedlinePlus

... are benzoyl peroxide, azelaic acid, glycolic acid, and salicylic acid. Prescription acne medications include tretinoin, adapalene, dapsone, and ... ACOG) recommends topical benzoyl peroxide, azelaic acid, topical salicylic acid and glycolic acid for treatment of acne in ...

Yearly trend of dicarboxylic acids in organic aerosols from south of Sweden and source attribution

NASA Astrophysics Data System (ADS)

Hyder, Murtaza; Genberg, Johan; Sandahl, Margareta; Swietlicki, Erik; Jönsson, Jan Åke

2012-09-01

Seven aliphatic dicarboxylic acids (C3-C9) along with phthalic acid, pinic acid and pinonic acid were determined in 35 aerosol (PM10) samples collected over the year at Vavihill sampling station in south of Sweden. Mixture of dichloromethane and methanol (ratio 1:3) was preferred over water for extraction of samples and extraction was assisted by ultrasonic agitation. Analytes were derivatized using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) containing 1% trimethylsilyl chloride and analyzed using gas chromatography/mass spectrometry. Among studied analytes, azelaic acid was found maximum with an average concentration of 6.0 ± 3.6 ng m-3 and minimum concentration was found for pimelic acid (1.06 ± 0.63 ng m-3). A correlation coefficients analysis was used for defining the possible sources of analytes. Higher dicarboxylic acids (C7-C9) showed a strong correlation with each other (correlation coefficients (r) range, 0.96-0.97). Pinic and pinonic acids showed an increase in concentration during summer. Lower carbon number dicarboxylic acids (C3-C6) and phthalic acid were found strongly correlated, but showed a poor correlation with higher carbon number dicarboxylic acids (C7-C9), suggesting a different source for them. Biomass burning, vehicle exhaust, photo-oxidation of volatile organic compounds (natural and anthropogenic emissions) were possible sources for dicarboxylic acids.

Water-soluble dicarboxylic acids and ketocarboxylic acids in the aerosols collected during ACE-Asia/C-130 aircraft campaign 2001

NASA Astrophysics Data System (ADS)

Kawamura, K.; Mochida, M.; Uemoto, N.; Bertram, T.; Huebert, B.

2001-12-01

During the ACE-Asia campaign with C-130 aircraft, aerosol samples were collected over the western North Pacific, East China Sea, and Japan Sea, as well as over Japanese Islands and Korean Peninsula in 8 April to 3 May 2001. The filter samples (N=15) were extracted with organic-free pure water to separate water-soluble dicarboxylic acids and related compounds. The extracts were reacted with 14% BF3 in n-butanol and the dibutyl esters and other derivatives were determined using a capillary GC and GC/MS. The results showed that 14 species of diacids (C2-C11) and 4 species of ketoacids (C2-C4) were detected in the aerosols over the East Asia. Total concentrations of the diacids were 113-500 (av. 330) ng/m3 whereas those of ketoacids were 43-260 (av. 103) ng/m3. The concentrations are equivalent to or more abundant than those reported for the urban Tokyo atmosphere in this season on the ground level. All the samples showed that oxalic acid (C2) is the most abundant diacid, which accounted for 58-83% of total diacids. These values are greater than that (ca. 50%) reported in the urban air near the ground, suggesting that oxalic acid is preferentially produced and/or longer diacids are selectively decomposed in the upper troposphere. Malonic (C3) acid is the second most abundant species followed by succinic (C4) acid. Longer diacids are less abundant, but azelaic (C9) acid is generally more abundant than C6-C8 diacids. Glyoxylic acid (C2) is the most abundant ketoacid followed by pyruvic acid. However, C3 and C4 omega-oxoacids were found as minor species. Although oxalic acid is the dominant component in the aerosols, few samples showed the predominance of glyoxylic acid over oxalic acid. This feature has not been reported for the urban aerosols collected near the ground level. We will discuss a potential photochemical production of water-soluble organic acids in the upper troposphere over the eastern ridge of the Asian continent.

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

Jung, Ho Won; Tschaplinski, Timothy J; Wang, Lin

Upon local infection, plants possess inducible systemic defense responses against their natural enemies. Bacterial infection results in the accumulation to high levels of the mobile metabolite C9-dicarboxylic acid azelaic acid in the vascular sap of Arabidopsis. Azelaic acid confers local and systemic resistance against Pseudomonas syringae. The compound primes plants to strongly accumulate salicylic acid (SA), a known defense signal, upon infection. Mutation of a gene induced by azelaic acid (AZI1) results in the specific loss in plants of systemic immunity triggered by pathogen or azelaic acid and of the priming of SA induction. AZI1, a predicted secreted protein, ismore » also important for generating vascular sap that confers disease resistance. Thus, azelaic acid and AZI1 comprise novel components of plant systemic immunity involved in priming defenses.« less

Carbonaceous aerosol characterization in the Amazon basin, Brazil: novel dicarboxylic acids and related compounds

NASA Astrophysics Data System (ADS)

Kubátová, Alena; Vermeylen, Reinhilde; Claeys, Magda; Cafmeyer, Jan; Maenhaut, Willy; Roberts, Greg; Artaxo, Paulo

High-resolution capillary gas chromatography (GC) and GC/mass spectrometry (MS) were employed for the quantitative determination of dichloromethane-extractable organic compounds in total and size-fractionated aerosol samples which were collected in the Amazon basin, Brazil, during the wet season, as part of the LBA-CLAIRE-98 experiment. Special emphasis was placed on the characterization and identification of several novel unknown dicarboxylic acids and related oxidative degradation products. This class of acidic products was enriched in the fine size fraction, suggesting that they were secondary organic aerosol products formed by gas-to-particle conversion. Some of the unknowns contributed more to the class of dicarboxylic acids than the major known compound, nonadioic acid (azelaic acid). The same unknowns were also observed in urban aerosol samples collected on hot summer days in Gent, Belgium. For the characterization and structure elucidation of the unknowns, various types of derivatizations and fractionation by solid-phase extraction were employed in combination with GC/MS. Four unknowns were identified. The most abundant were two derivatives of glutaric acid, 3-isopropyl pentanedioic acid and 3-acetyl pentanedioic acid. The other two identified unknowns were another oxo homologue, 3-acetyl hexanedioic acid, and, interestingly, 3-carboxy heptanedioic acid. To our knowledge, the occurrence of these four compounds in atmospheric aerosols has not yet been reported. The biogenic precursors of the novel identified compounds could not be pinpointed, but most likely include monoterpenes and fatty acids.

Epoxy Pipelining Composition and Method of Manufacture.

DTIC Science & Technology

1994-12-14

exemplary curing agent blend was prepared by reacting azelaic acid 3 (nonanedioic acid ), hexanoic acid , triethylene tetramine 4 (NH 2CH2CH2NHCH2CH2NHCH2CH...2NH2; TETA) and benzyl alcohol. The exemplary 5 curing agent blend was prepared as follows: 6 (a) Azelaic acid (solid; 90.9 gm.; 0.483 moles; C 9H 16 0...heated to 230 ’C over 10 - 20 11 minutes in a silicone oil bath. As the azelaic acid melted into a liquid, the 12 reaction mixture was stirred using a

Azelaic Acid Topical

MedlinePlus

... the bacteria that infect pores and by decreasing production of keratin, a natural substance that can lead ... send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http:// ...

Product study of oleic acid ozonolysis as function of humidity

NASA Astrophysics Data System (ADS)

Vesna, O.; Sax, M.; Kalberer, M.; Gaschen, A.; Ammann, M.

The heterogeneous reaction of ozone with oleic acid (OA) aerosol particles was studied as function of humidity and reaction time in an aerosol flow reactor using an off-line gas chromatography mass spectrometry (GC-MS) technique. We report quantitative yields of the major C9 ozonolysis products in both gas and condensed phases and the effect of relative humidity on the product distribution. The measurements were carried out with OA aerosol particles at room temperature. The results indicate that the product yields are increasing with increasing relative humidity during the reaction. Nonanal (NN) was detected as the major gas-phase product (55.6 ± 2.3%), with 94.5 ± 2.4% of the NN yield in the gas, and 5.5 ± 2.7% in the particulate phase, whereas nonanoic, oxononanoic and azelaic acids were detected exclusively in the particulate phase. Using UV-spectrometry, we observed that peroxides make up the largest fraction of products, about half of the product aerosol mass, and their concentration decreased with increasing humidity.

Dicarboxylic acids, oxoacids, benzoic acid, α-dicarbonyls, WSOC, OC, and ions in spring aerosols from Okinawa Island in the western North Pacific Rim: size distributions and formation processes

NASA Astrophysics Data System (ADS)

Deshmukh, D. K.; Kawamura, K.; Lazaar, M.; Kunwar, B.; Boreddy, S. K. R.

2015-09-01

Size-segregated aerosols (9-stages from < 0.43 to > 11.3 μm in diameter) were collected at Cape Hedo, Okinawa in spring 2008 and analyzed for water-soluble diacids (C2-C12), ω-oxoacids (ωC2-ωC9), pyruvic acid, benzoic acid and α-dicarbonyls (C2-C3) as well as water-soluble organic carbon (WSOC), organic carbon (OC) and major ions. In all the size-segregated aerosols, oxalic acid (C2) was found as the most abundant species followed by malonic and succinic acids whereas glyoxylic acid (ωC2) was the dominant oxoacid and glyoxal (Gly) was more abundant than methylglyoxal. Diacids (C2-C5), ωC2 and Gly as well as WSOC and OC peaked at 0.65-1.1 μm in fine mode whereas azelaic (C9) and 9-oxononanoic (ωC9) acids peaked at 3.3-4.7 μm in coarse mode. Sulfate and ammonium are enriched in fine mode whereas sodium and chloride are in coarse mode. These results imply that water-soluble species in the marine aerosols could act as cloud condensation nuclei (CCN) to develop the cloud cover over the western North Pacific Rim. The organic species are likely produced by a combination of gas-phase photooxidation, and aerosol-phase or in-cloud processing during long-range transport. The coarse mode peaks of malonic and succinic acids were obtained in the samples with marine air masses, suggesting that they may be associated with the reaction on sea salt particles. Bimodal size distributions of longer-chain diacid (C9) and oxoacid (ωC9) with a major peak in the coarse mode suggest their production by photooxidation of biogenic unsaturated fatty acids via heterogeneous reactions on sea salt particles.

Patient-reported outcomes of azelaic acid foam 15% for patients with papulopustular rosacea: secondary efficacy results from a randomized, controlled, double-blind, phase 3 trial.

PubMed

Tyring, Stephen; Solomon, James A; Staedtler, Gerald; Lott, Jason P; Nkulikiyinka, Richard; Shakery, Kaweh

2016-10-01

Patient-reported treatment outcomes are important for evaluating the impact of drug therapies on patient experience. A randomized, double-blind, vehicle-controlled, parallel-group, multicenter, phase 3 study was conducted in 961 participants to assess patient perception of efficacy, utility, and effect on quality of life (QOL) of an azelaic acid (AzA) 15% foam formulation for the treatment of papulopustular rosacea (PPR). Secondary end points included patient-reported global assessment of treatment response, global assessment of tolerability, and opinion on cosmetic acceptability and practicability of product use. Quality of life assessments included the Dermatology Quality of Life Index (DLQI) and Rosacea Quality of Life Index (RosaQOL). Self-reported global assessment of treatment response favored AzA foam over vehicle foam (P<.001), with 57.2% of the AzA foam group reporting excellent or good improvement versus 44.7% in the vehicle foam group. Tolerability was rated excellent or good in 67.8% of the AzA foam group versus 78.2% of the vehicle foam group. Mean overall DLQI scores at end of treatment (EoT) were improved (P=.018) in favor of the AzA foam group compared with the vehicle foam group. Both treatment groups showed improvements in RosaQOL. Treatment with AzA foam was associated with improved QOL and meaningful reductions in the patient-perceived burden of PPR, which correlates with earlier reported primary end points of this study and supports the inclusion of patient perspectives in studies evaluating the effects of topical dermatologic treatments.

Priming of plant resistance by natural compounds. Hexanoic acid as a model

PubMed Central

Aranega-Bou, Paz; de la O Leyva, Maria; Finiti, Ivan; García-Agustín, Pilar; González-Bosch, Carmen

2014-01-01

Some alternative control strategies of currently emerging plant diseases are based on the use of resistance inducers. This review highlights the recent advances made in the characterization of natural compounds that induce resistance by a priming mechanism. These include vitamins, chitosans, oligogalacturonides, volatile organic compounds, azelaic and pipecolic acid, among others. Overall, other than providing novel disease control strategies that meet environmental regulations, natural priming agents are valuable tools to help unravel the complex mechanisms underlying the induced resistance (IR) phenomenon. The data presented in this review reflect the novel contributions made from studying these natural plant inducers, with special emphasis placed on hexanoic acid (Hx), proposed herein as a model tool for this research field. Hx is a potent natural priming agent of proven efficiency in a wide range of host plants and pathogens. It can early activate broad-spectrum defenses by inducing callose deposition and the salicylic acid (SA) and jasmonic acid (JA) pathways. Later it can prime pathogen-specific responses according to the pathogen’s lifestyle. Interestingly, Hx primes redox-related genes to produce an anti-oxidant protective effect, which might be critical for limiting the infection of necrotrophs. Our Hx-IR findings also strongly suggest that it is an attractive tool for the molecular characterization of the plant alarmed state, with the added advantage of it being a natural compound. PMID:25324848

Metabolomics identifies an inflammatory cascade involved in dioxin- and diet-induced steatohepatitis

PubMed Central

Matsubara, Tsutomu; Tanaka, Naoki; Krausz, Kristopher W.; Manna, Soumen K.; Kang, Dong Wook; Anderson, Erik R.; Luecke, Hans; Patterson, Andrew D.; Shah, Yatrik M.; Gonzalez, Frank J.

2012-01-01

Summary 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is among the most potent environmentally toxic compounds. Serum metabolomics identified azelaic acid-mono esters as significantly increased metabolites after TCDD treatment, due to down-regulation of hepatic carboxylesterase 3 (CES3, also known as triglyceride hydrolase) expression in an arylhydrocarbon receptor (AhR)-dependent manner in mice. The decreased CES3 expression was accomplished by TCDD-stimulated TGFβ-SMAD3 and IL6-STAT3 signaling, but not by direct AhR signaling. Methionine- and choline-deficient (MCD) diet-treated mice also showed enhanced serum azelaic acid-mono ester levels following attenuation of hepatic CES3 expression, while db/db mice did not, thus suggesting an association with steatohepatitis. Forced expression of CES3 reversed serum azelaic acid-mono ester/azelaic acid ratios and hepatic TGFβ mRNA levels in TCDD- and MCD diet-treated mice and ameliorated steatohepatitis induced by MCD diet. These results support the view that azelaic acid-mono esters are possible indicators of TCDD exposure and steatohepatitis, and suggest a link between CES3, TGFβ, and steatohepatitis. PMID:23140643

Atmospheric oxalic acid and related secondary organic aerosols in Qinghai Lake, a continental background site in Tibet Plateau

NASA Astrophysics Data System (ADS)

Meng, Jingjing; Wang, Gehui; Li, Jianjun; Cheng, Chunlei; Cao, Junji

2013-11-01

Summertime PM2.5 aerosols collected from Qinghai Lake (3200 m a.s.l.), a remote continental site in the northeastern part of Tibetan Plateau, were analyzed for dicarboxylic acids (C2-C11), ketocarboxylic acids and α-dicarbonyals. Oxalic acid (C2) is the dominant dicarboxylic acid in the samples, followed by malonic, succinic and azelaic acids. Total dicarboxylic acids (231 ± 119 ng m-3), ketocarboxylic acids (8.4 ± 4.3 ng m-3), and α-dicarbonyls (2.7 ± 2.1 ng m-3) at the Tibetan background site are 2-5 times less than those detected in lowland areas such as 14 Chinese megacities. Compared to those in other urban and marine areas enhancements in relative abundances of C2/total diacids and diacids-C/WSOC of the PM2.5 samples suggest that organic aerosols in the region are more oxidized due to strong solar radiation. Molecular compositions and air mass trajectories demonstrate that the above secondary organic aerosols in the Qinghai Lake atmosphere are largely derived from long-range transport. Ratios of oxalic acid, glyoxal and methylglyoxal to levoglucosan in PM2.5 aerosols emitted from household burning of yak dung, a major energy source for Tibetan in the region, are 30-400 times lower than those in the ambient air, which further indicates that primary emission from biomass burning is a negligible source of atmospheric oxalic acid and α-dicarbonyls at this background site.

Size-dependent chemical ageing of oleic acid aerosol under dry and humidified conditions

NASA Astrophysics Data System (ADS)

Al-Kindi, Suad S.; Pope, Francis D.; Beddows, David C.; Bloss, William J.; Harrison, Roy M.

2016-12-01

A chemical reaction chamber system has been developed for the processing of oleic acid aerosol particles with ozone under two relative humidity conditions: dry and humidified to 65 %. The apparatus consists of an aerosol flow tube, in which the ozonolysis occurs, coupled to a scanning mobility particle sizer (SMPS) and an aerosol time-of-flight mass spectrometer (ATOFMS) which measure the evolving particle size and composition. Under both relative humidity conditions, ozonolysis results in a significant decrease in particle size and mass which is consistent with the formation of volatile products that partition from the particle to the gas phase. Mass spectra derived from the ATOFMS reveal the presence of the typically observed reaction products: azelaic acid, nonanal, oxononanoic acid and nonanoic acid, as well as a range of higher molecular weight products deriving from the reactions of reaction intermediates with oleic acid and its oxidation products. These include octanoic acid and 9- and 10-oxooctadecanoic acid, as well as products of considerably higher molecular weight. Quantitative evaluation of product yields with the ATOFMS shows a marked dependence upon both particle size association (from 0.3 to 2.1 µm diameter) and relative humidity. Under both relative humidity conditions, the percentage residual of oleic acid increases with increasing particle size and the main lower molecular weight products are nonanal and oxononanoic acid. Under dry conditions, the percentage of higher molecular weight products increases with increasing particle size due to the poorer internal mixing of the larger particles. Under humidified conditions, the percentage of unreacted oleic acid is greater, except in the smallest particle fraction, with little formation of high molecular weight products relative to the dry particles. It is postulated that water reacts with reactive intermediates, competing with the processes which produce high molecular weight products. Whilst the

Piezoelectric crystal microbalance measurements of enthalpy of sublimation of C2-C9 dicarboxylic acids

NASA Astrophysics Data System (ADS)

Dirri, F.; Palomba, E.; Longobardo, A.; Zampetti, E.

2015-07-01

We present here a novel experimental setup able to measure the enthalpy of sublimation of a given compound by means of Piezoelectric Crystal Microbalances (PCM). This experiment was performed in the TG-Lab facility in IAPS-INAF, dedicated to the development of TGA sensors for space measurements, such as detection of organic and non-organic volatile species and refractory materials in planetary environments. In order to study physical-chemical processes concerning the Volatile Organic Compounds (VOC) present in atmospheric environments, the setup has been tested on Dicarboxylic acids. Acids with low molecular weight are among the components of organic fraction of particulate matter in the atmosphere, coming from different sources (biogenic and anthropogenic). Considering their relative abundance, it is useful to consider Dicarboxylic acid as "markers" to define the biogenic or anthropogenic origin of the aerosol, thus obtaining some information of the emission sources. In this work, a temperature controlled effusion cell was used to sublimate VOC, creating a molecular flux that was collimated onto a cold PCM. The VOC re-condensed onto the PCM quartz crystal allowing the determination of the deposition rate. From the measurements of deposition rates, it was possible to infer the enthalpy of sublimation of Adipic acid, i.e. Δ Hsub: 141.6 ± 0.8 kJ mol-1, Succinic acid, i.e. 113.3 ± 1.3 kJ mol-1, Oxalic acid, i.e. 62.5 ± 3.1 kJ mol-1 and Azelaic acid, i.e. 124.2 ± 1.2 kJ mol-1 (weight average values). The results obtained are in very good agreement with literature within 10 % for the Adipic, Succinic and Oxalic acid.

A review of dicarboxylic acids and related compounds in atmospheric aerosols: Molecular distributions, sources and transformation

NASA Astrophysics Data System (ADS)

Kawamura, Kimitaka; Bikkina, Srinivas

2016-03-01

This review aims to update our understanding on molecular distributions of water-soluble dicarboxylic acids and related compounds in atmospheric aerosols with a focus on their geographical variability, size distribution, sources and formation pathways. In general, molecular distributions of diacids in aerosols from the continental sites and over the open ocean waters are often characterized by the predominance of oxalic acid (C2) followed by malonic acid (C3) and/or succinic acid (C4), while those sampled over the polar regions often follow the order of C4 ≥ C2 and C3. The most abundant and ubiquitous diacid is oxalic acid, which is principally formed via atmospheric oxidation of its higher homologues of long chain diacids and other pollution-derived organic precursors (e.g., olefins and aromatic hydrocarbons). However, its occurrence in marine aerosols is mainly due to the transport from continental outflows (e.g., East Asian outflow during winter/spring to the North Pacific) and/or governed by photochemical/aqueous phase oxidation of biogenic unsaturated fatty acids (e.g., oleic acid) and isoprene emitted from the productive open ocean waters. The long-range atmospheric transport of pollutants from mid latitudes to the Arctic in dark winter facilitates to accumulate the reactants prior to their intense photochemical oxidation during springtime polar sunrise. Furthermore, the relative abundances of C2 in total diacid mass showed similar temporal trends with downward solar irradiation and ambient temperatures, suggesting the significance of atmospheric photochemical oxidation processing. Compound-specific isotopic analyses of oxalic acid showed the highest δ13C among diacids whereas azelaic acid showed the lowest value, corroborating the significance of atmospheric aging of oxalic acid. On the other hand, other diacids gave intermediate values between these two diacids, suggesting that aging of oxalic acid is associated with 13C enrichment.

Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

NASA Astrophysics Data System (ADS)

Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

2014-08-01

Sources, composition and occurrence of secondary organic aerosols in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeastern Greenland, during the full annual cycle of 2008 and 2010, respectively. Speciation of organic acids, organosulfates and nitrooxy organosulfates - from both anthropogenic and biogenic precursors were in focus. A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate and 3-methyl-1,2,3-butanetricarboxylic acid), 12 organosulfates and 1 nitrooxy organosulfate were identified in aerosol samples from the two sites using a high-performance liquid chromatograph (HPLC) coupled to a quadrupole Time-of-Flight mass spectrometer. At Station Nord, compound concentrations followed a distinct annual pattern, where high mean concentrations of organosulfates (47 ± 14 ng m-3) and organic acids (11.5 ± 4 ng m-3) were observed in January, February and March, contrary to considerably lower mean concentrations of organosulfates (2 ± 3 ng m-3) and organic acids (2.2 ± 1 ng m-3) observed during the rest of the year. At Zeppelin Mountain, organosulfate and organic acid concentrations remained relatively constant during most of the year at a mean concentration of 15 ± 4 ng m-3 and 3.9 ± 1 ng m-3, respectively. However during four weeks of spring, remarkably higher concentrations of total organosulfates (23-36 ng m-3) and total organic acids (7-10 ng m-3) were observed. Elevated organosulfate and organic acid concentrations coincided with the Arctic haze period at both stations, where northern Eurasia was identified as the main source region. Air mass transport from northern Eurasia to Zeppelin Mountain was associated with a 100% increase in the number of detected organosulfate species compared with periods of air mass transport from the Arctic Ocean, Scandinavia and Greenland. The results from this

Long-term safety of ivermectin 1% cream vs azelaic acid 15% gel in treating inflammatory lesions of rosacea: results of two 40-week controlled, investigator-blinded trials.

PubMed

Stein Gold, Linda; Kircik, Leon; Fowler, Joseph; Jackson, J Mark; Tan, Jerry; Draelos, Zoe; Fleischer, Alan; Appell, Melanie; Steinhoff, Martin; Lynde, Charles; Sugarman, Jeffrey; Liu, Hong; Jacovella, Jean

2014-11-01

Papulopustular rosacea (PPR) is characterized by facial erythema and inflammatory lesions believed to be primarily caused by dysregulation of the innate immune system. More recent evidence also suggests that Demodex folliculorum mites may contribute to the etiology of PPR. Ivermectin (IVM) 1% cream is a novel topical treatment developed to treat PPR. Two phase 3 trials have demonstrated that IVM 1% cream was significantly better than vehicle at investigator global assessment (IGA) success rate and lesion reductions and that it was safe and well tolerated. Two 40-week extension studies of those trials were conducted to assess the long-term safety of IVM 1% cream vs azelaic acid (AzA) 15% gel. Subjects originally treated with IVM 1% continued on IVM 1% and those originally treated with vehicle switched to AzA 15% gel. IVM 1% cream was safe throughout the study with a lower incidence of related adverse events (AEs) compared to AzA 15% gel. No subjects in the IVM 1% cream group discontinued either study due to a related AE. IVM 1% also continued to be efficacious during the 40-week extension studies as the percentage of subjects with IGA scores of clear or almost clear was higher at the end of the study compared to baseline. The results of these 40-week extension studies support the use of IVM 1% cream as a long-term therapy for PPR as IVM 1% cream was shown to be safe and effective for up to 52 weeks of total treatment.

Stable carbon isotopic compositions of total carbon, dicarboxylic acids and glyoxylic acid in the tropical Indian aerosols: Implications for sources and photochemical processing of organic aerosols

NASA Astrophysics Data System (ADS)

Pavuluri, Chandra Mouli; Kawamura, Kimitaka; Swaminathan, T.; Tachibana, Eri

2011-09-01

The tropical Indian aerosols (PM10) collected on day- and nighttime bases in winter and summer, 2007 from Chennai (13.04°N; 80.17°E) were studied for stable carbon isotopic compositions (δ13C) of total carbon (TC), individual dicarboxylic acids (C2-C9) and glyoxylic acid (ωC2). δ13C values of TC ranged from -23.9‰ to -25.9‰ (-25.0 ± 0.6‰; n = 49). Oxalic (C2) (-17.1 ± 2.5‰), malonic (C3) (-20.8 ± 1.8‰), succinic (C4) (-22.5 ± 1.5‰) and adipic (C6) (-20.6 ± 4.1‰) acids and ωC2 acid (-22.4 ± 5.5‰) were found to be more enriched with 13C compared to TC. In contrast, suberic (C8) (-29.4 ± 1.8‰), phthalic (Ph) (-30.1 ± 3.5‰) and azelaic (C9) (-28.4 ± 5.8‰) acids showed smaller δ13C values than TC. Based on comparisons of δ13C values of TC in Chennai aerosols to those (-24.7 ± 2.2‰) found in unburned cow-dung samples collected from Chennai and isotopic signatures of the particles emitted from point sources, we found that biofuel/biomass burning are the major sources of carbonaceous aerosols in South and Southeast Asia. The decrease in δ13C values of C9 diacid by about 5‰ from winter to summer suggests that tropical plant emissions also significantly contribute to organic aerosol in this region. Significant increase in δ13C values from C4 to C2 diacids in Chennai aerosols could be attributed for their photochemical processing in the tropical atmosphere during long-range transport from source regions.

Plant pathogen resistance

DOEpatents

Greenberg, Jean T.; Jung, Ho Won; Tschaplinski, Timothy

2015-10-20

Azelaic acid or its derivatives or analogs induce a robust and a speedier defense response against pathogens in plants. Azelaic acid treatment alone does not induce many of the known defense-related genes but activates a plant's defense signaling upon pathogen exposure.

Plant pathogen resistance

DOEpatents

Greenberg, Jean T; Jung, Ho Won; Tschaplinski, Timothy

2012-11-27

Azelaic acid or its derivatives or analogs induce a robust and a speedier defense response against pathogens in plants. Azelaic acid treatment alone does not induce many of the known defense-related genes but activates a plant's defense signaling upon pathogen exposure.

Dicarboxylic acids, oxoacids, benzoic acid, α-dicarbonyls, WSOC, OC, and ions in spring aerosols from Okinawa Island in the western North Pacific Rim: size distributions and formation processes

NASA Astrophysics Data System (ADS)

Deshmukh, Dhananjay K.; Kawamura, Kimitaka; Lazaar, Manuel; Kunwar, Bhagawati; Boreddy, Suresh K. R.

2016-04-01

Size-segregated aerosols (nine stages from < 0.43 to > 11.3 µm in diameter) were collected at Cape Hedo, Okinawa, in spring 2008 and analyzed for water-soluble diacids (C2-C12), ω-oxoacids (ωC2-ωC9), pyruvic acid, benzoic acid, and α-dicarbonyls (C2-C3) as well as water-soluble organic carbon (WSOC), organic carbon (OC), and major ions (Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-, and MSA-). In all the size-segregated aerosols, oxalic acid (C2) was found to be the most abundant species, followed by malonic and succinic acids, whereas glyoxylic acid (ωC2) was the dominant oxoacid and glyoxal (Gly) was more abundant than methylglyoxal. Diacids (C2-C5), ωC2, and Gly as well as WSOC and OC peaked at fine mode (0.65-1.1 µm) whereas azelaic (C9) and 9-oxononanoic (ωC9) acids peaked at coarse mode (3.3-4.7 µm). Sulfate and ammonium were enriched in fine mode, whereas sodium and chloride were in coarse mode. Strong correlations of C2-C5 diacids, ωC2 and Gly with sulfate were observed in fine mode (r = 0.86-0.99), indicating a commonality in their secondary formation. Their significant correlations with liquid water content in fine mode (r = 0.82-0.95) further suggest an importance of the aqueous-phase production in Okinawa aerosols. They may also have been directly emitted from biomass burning in fine mode as supported by strong correlations with potassium (r = 0.85-0.96), which is a tracer of biomass burning. Bimodal size distributions of longer-chain diacid (C9) and oxoacid (ωC9) with a major peak in the coarse mode suggest that they were emitted from the sea surface microlayers and/or produced by heterogeneous oxidation of biogenic unsaturated fatty acids on sea salt particles.

Source and reaction pathways of dicarboxylic acids, ketoacids and dicarbonyls in arctic aerosols: One year of observations

NASA Astrophysics Data System (ADS)

Kawamura, Kimitaka; Kasukabe, Hideki; Barrie, Leonard A.

Normal saturated (C 2C 11) and unsaturated (C 4C 5, C 8) dicarboxylic acids were measured in arctic aerosol samples collected weekly at Alert, Canada in 1987-1988. In all seasons, oxalic (C 2) acid was usually the dominant diacid species (1.8-70 ng m -3, av. 14 ± 12 ng m -3) followed by malonic (C 3; 0.05-19 ng m -3, av. 2.5 ± 3.3 ng m -3) and succinic (C 4; 0.51-18 ng m -3, av. 3.8 ± 3.5 ng m -3) acids. The total concentrations of dicarboxylic acids showed a seasonal variation (4.3-97 ng m -3, av. 25 ± 20 ng m -3),with two maxima in September to October and in March to April. The autumn peak is characterized by high concentrations of oxalic acid and azelaic (C 9) acids, which were probably caused by enhanced contributions from anthropogenic and biogenic sources, respectively, followed by photochemical reactions. This is consistent with higher concentrations of n-alkanes from terrestrial plant waxes and of soil-derived aluminum in the autumn aerosol samples. On the other hand, during "Arctic Sunrise" in March to April, oxalic, malonic and succinic acids as well as some other (C 5C 6) diacids were 5 to 20 times more abundant than in the preceding dark winter months, suggesting that diacids are produced in situ by secondary photochemical oxidation of organic pollutants carried to the Arctic. ω-Oxocarboxylic acids (C 2C 5, C 9), pyruvic acid and α-dicarbonyls (methylglyoxal and glyoxal) were also detected in the arctic aerosols. Their concentration also showed spring maxima; however, they were observed a few weeks earlier than the spring peak of diacids. The ω-oxoacids are likely intermediates to the production of α,ω-dicarboxylic acids at the polar sunrise.

Photoelectron resonance capture ionization-aerosol mass spectrometry of the ozonolysis products of oleic acid particles: Direct measure of higher molecular weight oxygenates

NASA Astrophysics Data System (ADS)

Zahardis, James; Lafranchi, Brian W.; Petrucci, Giuseppe A.

2005-04-01

The heterogeneous reaction of particle-phase 9-octadecenoic acid (oleic acid) and gas-phase ozone in a flow reactor was studied by photoelectron resonance capture ionization (PERCI) mass spectrometry. This soft ionization technique facilitated one of the first simultaneous, direct observations of all four of the major products predicted for this reaction: nonanal, nonanoic acid, 9-oxononanoic acid, and azelaic acid. In addition, a series of higher molecular weight oxygenated compounds were observed directly for the first time. The proposed structures are all cyclic oxygenates and contain the oxygen-oxygen moiety, including secondary ozonides and cyclic geminal diperoxides. Mechanisms for the formation of these products are proposed. The mechanisms are generally 1,3-dipolar cycloadditions that lead to five- and six-member oxygen-containing rings. The mechanisms are shown to involve short-lived Criegee intermediates reacting with aldehydes and other Criegee intermediates. Atmospheric implications of these higher molecular weight compounds are suggested and include enhancing the fatty acid medium's capacity to act as a source of radicals due to the prominence of the peroxide moiety. The low volatility coupled with the high polarity of these compounds may alter particle phase hygroscopicity that can enhance the cloud condensation nuclei properties of these particles.

Identification and quantification of antifungal compounds produced by lactic acid bacteria and propionibacteria.

PubMed

Le Lay, Céline; Coton, Emmanuel; Le Blay, Gwenaëlle; Chobert, Jean-Marc; Haertlé, Thomas; Choiset, Yvan; Van Long, Nicolas Nguyen; Meslet-Cladière, Laurence; Mounier, Jérôme

2016-12-19

Fungal growth in bakery products represents the most frequent cause of spoilage and leads to economic losses for industrials and consumers. Bacteria, such as lactic acid bacteria and propionibacteria, are commonly known to play an active role in preservation of fermented food, producing a large range of antifungal metabolites. In a previous study (Le Lay et al., 2016), an extensive screening performed both in vitro and in situ allowed for the selection of bacteria exhibiting an antifungal activity. In the present study, active supernatants against Penicillium corylophilum and Aspergillus niger were analyzed to identify and quantify the antifungal compounds associated with the observed activity. Supernatant treatments (pH neutralization, heating and addition of proteinase K) suggested that organic acids played the most important role in the antifungal activity of each tested supernatant. Different methods (HPLC, mass spectrometry, colorimetric and enzymatic assays) were then applied to analyze the supernatants and it was shown that the main antifungal compounds corresponded to lactic, acetic and propionic acids, ethanol and hydrogen peroxide, as well as other compounds present at low levels such as phenyllactic, hydroxyphenyllactic, azelaic and caproic acids. Based on these results, various combinations of the identified compounds were used to evaluate their effect on conidial germination and fungal growth of P. corylophilum and Eurotium repens. Some combinations presented the same activity than the bacterial culture supernatant thus confirming the involvement of the identified molecules in the antifungal activity. The obtained results suggested that acetic acid was mainly responsible for the antifungal activity against P. corylophilum and played an important role in E. repens inhibition. Copyright © 2016 Elsevier B.V. All rights reserved.

Improvement of Tissue Survival of Skin Flaps by 5α-Reductase Inhibitors: Possible Involvement of Nitric Oxide and Inducible Nitric Oxide Synthase

PubMed Central

Karimi, Ali Asghar; Ajami, Marjan; Asadi, Yasin; Aboutaleb, Nahid; Gorjipour, Fazel; Malekloo, Roya; Pazoki-Toroudi, Hamidreza

2015-01-01

Background: Skin flap grafting is a popular approach for reconstruction of critical skin and underlying soft tissue injuries. In a previous study, we demonstrated the beneficial effects of two 5α-reductase inhibitors, azelaic acid and finasteride, on tissue survival in a rat model of skin flap grafting. In the current study, we investigated the involvement of nitric oxide and inducible nitric oxide synthase (iNOS) in graft survival mediated by these agents. Methods: A number of 42 male rats were randomly allocated into six groups: 1, normal saline topical application; 2, azelaic acid (100 mg/flap); 3, finasteride (1 mg/flap); 4, injection of L-NG-nitroarginine methyl ester (L-NAME) (i.p., 20 mg/kg); 5, L-NAME (20 mg/kg, i.p.) + azelaic acid (100 mg/flap, topical); 6, L-NAME (20 mg/kg, i.p.) + finasteride (1 mg/flap, topical). Tissue survival, level of nitric oxide, and iNOS expression in groups were measured. Results: Our data revealed that azelaic acid and finasteride significantly increased the expression of iNOS protein and nitric oxide (NO) levels in graft tissue (P < 0.05). These increases in iNOS expression and NO level were associated with higher survival of the graft tissue. Conclusion: It appears that alterations of the NO metabolism are implicated in the azelaic acid- and finasteride-mediated survival of the skin flaps. PMID:25864816

Electrosorptive Detection of Simple Organic Compounds in Liquid Chromatography.

DTIC Science & Technology

1987-09-30

that there is some "noise" in the azelaic acid peak. Similar noise was also noted for other highly hydrophobic/surface-active compounds. .- Amines...3 97 ’For 20-jtL injections of 10 wm( concentration, E -- 0.525 V. 2Relative to glutaric acid . 3Higher (succinic) and lower ( azelaic , sebacic...dicarboxylic - acids , aminies, and -~anolamines. The difffeirential capacitance measurements were condte le zeo h gwhere adsorption of such species is most

Seasonal cycle and temperature dependence of pinene oxidation products, dicarboxylic acids and nitrophenols in fine and coarse air particulate matter

NASA Astrophysics Data System (ADS)

Zhang, Y. Y.; Müller, L.; Winterhalter, R.; Moortgat, G. K.; Hoffmann, T.; Pöschl, U.

2010-08-01

Filter samples of fine and coarse air particulate matter (PM) collected over a period of one year in central Europe (Mainz, Germany) were analyzed for water-soluble organic compounds (WSOCs), including the α- and β-pinene oxidation products pinic acid, pinonic acid and 3-methyl-1,2,3-butanetricarboxylic acid (3-MBTCA), as well as a variety of dicarboxylic acids and nitrophenols. Seasonal variations and other characteristic features in fine, coarse, and total PM (TSP) are discussed with regard to aerosol sources and sinks in comparison to data from other studies and regions. The ratios of adipic acid and phthalic acid to azelaic acid indicate that the investigated aerosol samples were mainly influenced by biogenic sources. A strong Arrhenius-type correlation was found between the 3-MBTCA concentration and inverse temperature (R2 = 0.79, n = 52, Ea = 126 ± 10 kJ mol-1, temperature range 275-300 K). Model calculations suggest that the temperature dependence observed for 3-MBTCA can be explained by enhanced photochemical production due to an increase of hydroxyl radical (OH) concentration with increasing temperature, whereas the influence of gas-particle partitioning appears to play a minor role. The results indicate that the OH-initiated oxidation of pinonic acid is the rate-limiting step in the formation of 3-MBTCA, and that 3-MBTCA may be a suitable tracer for the chemical aging of biogenic secondary organic aerosol (SOA) by OH radicals. An Arrhenius-type temperature dependence was also observed for the concentration of pinic acid (R2 = 0.60, n = 56, Ea = 84 ± 9 kJ mol-1); it can be tentatively explained by the temperature dependence of biogenic pinene emission as the rate-limiting step of pinic acid formation.

Seasonal cycle and temperature dependence of pinene oxidation products, dicarboxylic acids and nitrophenols in fine and coarse air particulate matter

NASA Astrophysics Data System (ADS)

Zhang, Y.; Müller, L.; Winterhalter, R.; Moortgat, G. K.; Hoffmann, T.; Pöschl, U.

2010-05-01

Filter samples of fine and coarse air particulate matter (PM) collected over a period of one year in central Europe (Mainz, Germany) were analyzed for water-soluble organic compounds (WSOCs), including the α- and β-pinene oxidation products pinic acid, pinonic acid and 3-methyl-1,2,3-butanetricarboxylic acid (3-MBTCA), as well as a variety of dicarboxylic acids and nitrophenols. Seasonal variations and other characteristic features in fine, coarse, and total PM (TSP) are discussed with regard to aerosol sources and sinks in comparison to data from other studies and regions. The ratios of adipic acid and phthalic acid to azelaic acid indicate that the investigated samples were mainly influenced by biogenic sources. A strong Arrhenius-type correlation was found between the 3-MBTCA concentration and inverse temperature (R2=0.79, n=52, Ea=126±10 kJ mol-1, temperature range 275-300 K). Model calculations suggest that the temperature dependence observed for 3-MBTCA can be explained by enhanced photochemical production due to an increase of hydroxyl radical (OH) concentration with increasing temperature, whereas the influence of gas-particle partitioning appears to play a minor role. The results indicate that the OH-initiated oxidation of pinonic acid is the rate-limiting step in the formation of 3-MBTCA, and that 3-MBTCA may be a suitable tracer for the chemical aging of biogenic secondary organic aerosol (SOA) by OH radicals. An Arrhenius-type temperature dependence was also observed for the concentration of pinic acid (R2=0.60, n=56, Ea=84±9 kJ mol-1); it can be tentatively explained by the temperature dependence of biogenic pinene emission as the rate-limiting step of pinic acid formation.

The oleic acid-ozone heterogeneous reaction system: products, kinetics, secondary chemistry, and atmospheric implications of a model system - a review

NASA Astrophysics Data System (ADS)

Zahardis, J.; Petrucci, G. A.

2007-02-01

The heterogeneous processing of organic aerosols by trace oxidants has many implications to atmospheric chemistry and climate regulation. This review covers a model heterogeneous reaction system (HRS): the oleic acid-ozone HRS and other reaction systems featuring fatty acids, and their derivatives. The analysis of the commonly observed aldehyde and organic acid products of ozonolysis (azelaic acid, nonanoic acid, 9-oxononanoic acid, nonanal) is described. The relative product yields are noted and explained by the observation of secondary chemical reactions. The secondary reaction products arising from reactive Criegee intermediates are mainly peroxidic, notably secondary ozonides and α-acyloxyalkyl hydroperoxide oligomers and polymers, and their formation is in accord with solution and liquid-phase ozonolysis. These highly oxygenated products are of low volatility and hydrophilic which may enhance the ability of particles to act as cloud condensation nuclei (CCN). The kinetic description of this HRS is critically reviewed. Most kinetic studies suggest this oxidative processing is either a near surface reaction that is limited by the diffusion of ozone or a surface based reaction. Internally mixed particles and coatings represent the next stage in the progression towards more realistic proxies of tropospheric organic aerosols and a description of the products and the kinetics resulting from the ozonolysis of these proxies, which are based on fatty acids or their derivatives, is presented. Finally, the main atmospheric implications of oxidative processing of particulate containing fatty acids are presented. These implications include the extended lifetime of unsaturated species in the troposphere facilitated by the presence of solids, semi-solids or viscous phases, and an enhanced rate of ozone uptake by particulate unsaturates compared to corresponding gas-phase organics. Ozonolysis of oleic acid enhances its CCN activity, which implies that oxidatively processed

[Studies on interaction of acid-treated nanotube titanic acid and amino acids].

PubMed

Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang

2010-06-01

Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

Studies on PGBx A Polymeric Derivative of Prostaglandin B1. I. Synthesis and Purification of PGBx.

DTIC Science & Technology

1978-10-30

synthesis and purification of PGB sub x via PGB sub 1, starting with azelaic acid . In addition, details of the in vitro mitochondrial assay are reported...Purified PGB sub x exhibiting maximal reactivation of mitochondrial phosphorylation has a mean molecular weight of 2350. The yield of PGB sub x based on azelaic acid was 4% and based on PGB sub 1 was 25%. (Author)

The oleic acid-ozone heterogeneous reaction system: products, kinetics, secondary chemistry, and atmospheric implications of a model system a review

NASA Astrophysics Data System (ADS)

Zahardis, J.; Petrucci, G. A.

2006-11-01

The heterogeneous processing of organic aerosols by trace oxidants has many implications to atmospheric chemistry and climate regulation. This review covers a model heterogeneous reaction system (HRS): the oleic acid-ozone HRS and other reaction systems featuring fatty acids, and their derivatives. The analysis of the primary products of ozonolysis (azelaic acid, nonanoic acid, 9-oxononanoic acid, nonanal) is described. Anomalies in the relative product yields are noted and explained by the observation of secondary chemical reactions. The secondary reaction products arising from reactive Criegee intermediates are mainly peroxidic, notably secondary ozonides and α-acyloxyalkyl hydroperoxide polymers. These highly oxygenated products are of low volatility and hydrophilic which may enhance the ability of particles to act as cloud condensation nuclei. The kinetic description of this HRS is critically reviewed. Most kinetic studies suggest this oxidative processing is either a near surface reaction that is limited by the diffusion of ozone or a surface based reaction. Internally mixed particles and coatings represent the next stage in the progression towards more realistic proxies of tropospheric organic aerosols and a description of the products and the kinetics resulting from the ozonolysis of these proxies, which are based on fatty acids or their derivatives, is presented. Finally, a series of atmospheric implications of oxidative processing of particulate containing fatty acids is presented. These implications include the extended lifetime of unsaturated species in the troposphere facilitated by the presence of solids, semisolids or viscous phases, and an enhanced rate of ozone uptake by particulate unsaturates compared to corresponding gas phase organics. Ozonolysis of oleic acid enhances its CCN activity, which implies that oxidatively processed particulate may contribute to indirect forcing of radiation. Other effects, including the potential role of aldehydic

Constitutively elevated salicylic acid levels alter photosynthesis and oxidative state but not growth in transgenic populus.

PubMed

Xue, Liang-Jiao; Guo, Wenbing; Yuan, Yinan; Anino, Edward O; Nyamdari, Batbayar; Wilson, Mark C; Frost, Christopher J; Chen, Han-Yi; Babst, Benjamin A; Harding, Scott A; Tsai, Chung-Jui

2013-07-01

Salicylic acid (SA) has long been implicated in plant responses to oxidative stress. SA overproduction in Arabidopsis thaliana leads to dwarfism, making in planta assessment of SA effects difficult in this model system. We report that transgenic Populus tremula × alba expressing a bacterial SA synthase hyperaccumulated SA and SA conjugates without negative growth consequences. In the absence of stress, endogenously elevated SA elicited widespread metabolic and transcriptional changes that resembled those of wild-type plants exposed to oxidative stress-promoting heat treatments. Potential signaling and oxidative stress markers azelaic and gluconic acids as well as antioxidant chlorogenic acids were strongly coregulated with SA, while soluble sugars and other phenylpropanoids were inversely correlated. Photosynthetic responses to heat were attenuated in SA-overproducing plants. Network analysis identified potential drivers of SA-mediated transcriptome rewiring, including receptor-like kinases and WRKY transcription factors. Orthologs of Arabidopsis SA signaling components NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1 and thioredoxins were not represented. However, all members of the expanded Populus nucleoredoxin-1 family exhibited increased expression and increased network connectivity in SA-overproducing Populus, suggesting a previously undescribed role in SA-mediated redox regulation. The SA response in Populus involved a reprogramming of carbon uptake and partitioning during stress that is compatible with constitutive chemical defense and sustained growth, contrasting with the SA response in Arabidopsis, which is transient and compromises growth if sustained.

Organosulfates and organic acids in Arctic aerosols: speciation, annual variation and concentration levels

NASA Astrophysics Data System (ADS)

Hansen, A. M. K.; Kristensen, K.; Nguyen, Q. T.; Zare, A.; Cozzi, F.; Nøjgaard, J. K.; Skov, H.; Brandt, J.; Christensen, J. H.; Ström, J.; Tunved, P.; Krejci, R.; Glasius, M.

2014-02-01

Sources, composition and occurrence of secondary organic aerosols (SOA) in the Arctic were investigated at Zeppelin Mountain, Svalbard, and Station Nord, northeast Greenland, during the full annual cycle of 2008 and 2010 respectively. We focused on the speciation of three types of SOA tracers: organic acids, organosulfates and nitrooxy organosulfates from both anthropogenic and biogenic precursors, here presenting organosulfate concentrations and compositions during a full annual cycle and chemical speciation of organosulfates in Arctic aerosols for the first time. Aerosol samples were analysed using High Performance Liquid Chromatography coupled to a quadrupole Time-of-Flight mass spectrometer (HPLC-q-TOF-MS). A total of 11 organic acids (terpenylic acid, benzoic acid, phthalic acid, pinic acid, suberic acid, azelaic acid, adipic acid, pimelic acid, pinonic acid, diaterpenylic acid acetate (DTAA) and 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA)), 12 organosulfates and one nitrooxy organosulfate were identified at the two sites. Six out of the 12 organosulfates are reported for the first time. Concentrations of organosulfates follow a distinct annual pattern at Station Nord, where high concentration were observed in late winter and early spring, with a mean total concentration of 47 (±14) ng m-3, accounting for 7 (±2)% of total organic matter, contrary to a considerably lower organosulfate mean concentration of 2 (±3) ng m-3 (accounting for 1 (±1)% of total organic matter) observed during the rest of the year. The organic acids followed the same temporal trend as the organosulfates at Station Nord; however the variations in organic acid concentrations were less pronounced, with a total mean organic acid concentration of 11.5 (±4) ng m-3 (accounting for 1.7 (±0.6)% of total organic matter) in late winter and early spring, and 2.2 (±1) ng m-3 (accounting for 0.9 (±0.4)% of total organic matter) during the rest of the year. At Zeppelin Mountain

Microbial degradation of poly(amino acid)s.

PubMed

Obst, Martin; Steinbüchel, Alexander

2004-01-01

Natural poly(amino acid)s are a group of poly(ionic) molecules (ionomers) with various biological functions and putative technical applications and play, therefore, an important role both in nature and in human life. Because of their biocompatibility and their synthesis from renewable resources, poly(amino acid)s may be employed for many different purposes covering a broad spectrum of medical, pharmaceutical, and personal care applications as well as the domains of agriculture and of environmental applications. Biodegradability is one important advantage of naturally occurring poly(amino acid)s over many synthetic polymers. The intention of this review is to give an overview about the enzyme systems catalyzing the initial steps in poly(amino acid) degradation. The focus is on the naturally occurring poly(amino acid)s cyanophycin, poly(epsilon-L-lysine) and poly(gamma-glutamic acid); but biodegradation of structurally related synthetic polyamides such as poly(aspartic acid) and nylons, which are known from various technical applications, is also included.

The Acid-Base Titration of a Very Weak Acid: Boric Acid

ERIC Educational Resources Information Center

Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

2012-01-01

A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

Omega-3 fatty acids: new insights into the pharmacology and biology of docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid.

PubMed

Davidson, Michael H

2013-12-01

Fish oil contains a complex mixture of omega-3 fatty acids, which are predominantly eicosapentaenoic acid (EPA), docosapentaenoic acid, and docosahexaenoic acid (DHA). Each of these omega-3 fatty acids has distinct biological effects that may have variable clinical effects. In addition, plasma levels of omega-3 fatty acids are affected not only by dietary intake, but also by the polymorphisms of coding genes fatty acid desaturase 1-3 for the desaturase enzymes that convert short-chain polyunsaturated fatty acids to long-chain polyunsaturated fatty acids. The clinical significance of this new understanding regarding the complexity of omega-3 fatty acid biology is the purpose of this review. FADS polymorphisms that result in either lower levels of long-chain omega-3 fatty acids or higher levels of long-chain omega-6 polyunsaturated fatty acids, such as arachidonic acid, are associated with dyslipidemia and other cardiovascular risk factors. EPA and DHA have differences in their effects on lipoprotein metabolism, in which EPA, with a more potent peroxisome proliferator-activated receptor-alpha effect, decreases hepatic lipogenesis, whereas DHA not only enhances VLDL lipolysis, resulting in greater conversion to LDL, but also increases HDL cholesterol and larger, more buoyant LDL particles. Overall, these results emphasize that blood concentrations of individual long-chain polyunsaturated fatty acids, which reflect both dietary intake and metabolic influences, may have independent, but also complementary- biological effects and reinforce the need to potentially provide a complex mixture of omega-3 fatty acids to maximize cardiovascular risk reduction.

EXAFS study of some coordination polymers of copper

NASA Astrophysics Data System (ADS)

Deshpande, A. P.

1995-02-01

The EXAFS spectra for (1) azelaic acid bis phenyl hydrazide, (2) azelaic acid bis 2,4 dinitro phenyl hydrazide and (3) sebacic acid bis phenyl hydrazide coordination polymers of copper were obtained using the EXAFS facility of the Daresbury Laboratory. The EXAFS analysis revealed that copper is surrounded by four nitrogen and two oxygen atoms in the first coordination shell, while the second coordination shell consists of two carbon atoms. This information suggests the octahedral geometry for the repeating units of polymeric complexes, in contrast to the square planar geometry previously proposed.

Stable carbon isotope ratios of low molecular weight dicarboxylic acids, ketoacids and glyoxal in marine aerosols from the western North Pacific: Long-term trends in Chichijima Island

NASA Astrophysics Data System (ADS)

Kawamura, K.; Tachibana, E.

2012-12-01

Dicarboxylic acids such as oxalic, malonic and succinic acids are the most abundant water-soluble organic compound class in aerosols. To better understand the source and photochemical processes of water-soluble organic aerosols in the remote marine aerosols, we measured stable carbon isotopic composition (δ13C) of dicarboxylic acids and related compounds using a GC/IR/MS technique. The aerosol samples were collected in 2001-2011 at a remote island, Chichijima (27°04'E; 142°13'N) in the western North Pacific. Here we present decadal variations of the isotopic composition of dicarboxylic acids (C2-C9), ketoacids (C2-C8) and glyoxal in summertime aerosols (June, July and August). The molecular distributions of diacids were characterized by the predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids. Oxalic acid showed higher δ13C values than other species ranging from -18‰ to -2‰ with no clear decadal trend. In contrast, C3 and C4 diacids showed δ13C values of -24 to -5‰ and -40 to -12‰ with a decadal decline. Glyoxal (-60 to -10‰) and ωC7 acid (-34 to -12‰) also showed lower values toward 2011. However, azelaic acid (C9) (-32 to -24‰) stayed relatively constant throughout the observation period. We will discuss the detailed isotopic compositions of these organic species in terms of the photochemical aging and processing in the western North Pacific and the changes in the sources and source regions.

Boric acid and boronic acids inhibition of pigeonpea urease.

PubMed

Reddy, K Ravi Charan; Kayastha, Arvind M

2006-08-01

Urease from the seeds of pigeonpea was competitively inhibited by boric acid, butylboronic acid, phenylboronic acid, and 4-bromophenylboronic acid; 4-bromophenylboronic acid being the strongest inhibitor, followed by boric acid > butylboronic acid > phenylboronic acid, respectively. Urease inhibition by boric acid is maximal at acidic pH (5.0) and minimal at alkaline pH (10.0), i.e., the trigonal planar B(OH)3 form is a more effective inhibitor than the tetrahedral B(OH)4 -anionic form. Similarly, the anionic form of phenylboronic acid was least inhibiting in nature.

Acid Rain

USGS Publications Warehouse

Bricker, Owen P.; Rice, Karen C.

1995-01-01

Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

PubMed

Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

2002-12-06

Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

Enantioselective oxidation of racemic lactic acid to D-lactic acid and pyruvic acid by Pseudomonas stutzeri SDM.

PubMed

Gao, Chao; Qiu, Jianhua; Li, Jingchen; Ma, Cuiqing; Tang, Hongzhi; Xu, Ping

2009-03-01

D-lactic acid and pyruvic acid are two important building block intermediates. Production of D-lactic acid and pyruvic acid from racemic lactic acid by biotransformation is economically interesting. Biocatalyst prepared from 9 g dry cell wt l(-1) of Pseudomonas stutzeri SDM could catalyze 45.00 g l(-1)DL-lactic acid into 25.23 g l(-1)D-lactic acid and 19.70 g l(-1) pyruvic acid in 10h. Using a simple ion exchange process, D-lactic acid and pyruvic acid were effectively separated from the biotransformation system. Co-production of d-lactic acid and pyruvic acid by enantioselective oxidation of racemic lactic acid is technically feasible.

Acne

MedlinePlus

... may contain benzoyl peroxide, sulfur, resorcinol, adapalene, or salicylic acid. They work by killing bacteria, drying up skin ... Prescription formulas of benzoyl peroxide, sulfur, resorcinol, or salicylic acid Topical azelaic acid For women whose acne is ...

Effect of propionic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

PubMed

Xu, Jian; Bao, Jia-Wei; Su, Xian-Feng; Zhang, Hong-Jian; Zeng, Xin; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2016-03-01

In this study, an integrated citric acid-methane fermentation process was established to solve the problem of wastewater treatment in citric acid production. Citric acid wastewater was treated through anaerobic digestion and then the anaerobic digestion effluent (ADE) was further treated and recycled for the next batch citric acid fermentation. This process could eliminate wastewater discharge and reduce water resource consumption. Propionic acid was found in the ADE and its concentration continually increased in recycling. Effect of propionic acid on citric acid fermentation was investigated, and results indicated that influence of propionic acid on citric acid fermentation was contributed to the undissociated form. Citric acid fermentation was inhibited when the concentration of propionic acid was above 2, 4, and 6 mM in initial pH 4.0, 4.5 and, 5.0, respectively. However, low concentration of propionic acid could promote isomaltase activity which converted more isomaltose to available sugar, thereby increasing citric acid production. High concentration of propionic acid could influence the vitality of cell and prolong the lag phase, causing large amount of glucose still remaining in medium at the end of fermentation and decreasing citric acid production.

Effect of baseline plasma fatty acids on eicosapentaenoic acid levels in individuals supplemented with alpha-linolenic acid.

PubMed

DeFilippis, Andrew P; Harper, Charles R; Cotsonis, George A; Jacobson, Terry A

2009-01-01

We previously reported a >50% increase in mean plasma eicosapentaenoic acid levels in a general medicine clinic population after supplementation with alpha-linolenic acid. In the current analysis, we evaluate the variability of changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid and evaluated the impact of baseline plasma fatty acids levels on changes in eicosapentaenoic acid levels in these individuals. Changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid ranged from a 55% decrease to a 967% increase. Baseline plasma fatty acids had no statistically significant effect on changes in eicosapentaenoic levels acid after alpha-linolenic acid supplementation. Changes in eicosapentaenoic acid levels varied considerably in a general internal medicine clinic population supplemented with alpha-linolenic acid. Factors that may impact changes in plasma eicosapentaenoic acid levels after alpha-linolenic acid supplementation warrant further study.

Specific bile acids inhibit hepatic fatty acid uptake

PubMed Central

Nie, Biao; Park, Hyo Min; Kazantzis, Melissa; Lin, Min; Henkin, Amy; Ng, Stephanie; Song, Sujin; Chen, Yuli; Tran, Heather; Lai, Robin; Her, Chris; Maher, Jacquelyn J.; Forman, Barry M.; Stahl, Andreas

2012-01-01

Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. Here we tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%. In summary, the data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease. PMID:22531947

[Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

PubMed

Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

2016-03-01

Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.

PubMed

Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

2012-11-01

A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ≈ Erie > Huron > Superior ≈ Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid.

A Strategy Combining Higher Energy C-Trap Dissociation with Neutral Loss- and Product Ion-Based MSn Acquisition for Global Profiling and Structure Annotation of Fatty Acids Conjugates

NASA Astrophysics Data System (ADS)

Bi, Qi-rui; Hou, Jin-jun; Yang, Min; Shen, Yao; Qi, Peng; Feng, Rui-hong; Dai, Zhuo; Yan, Bing-peng; Wang, Jian-wei; Shi, Xiao-jian; Wu, Wan-ying; Guo, De-an

2017-03-01

Fatty acids conjugates (FACs) are ubiquitous but found in trace amounts in the natural world. They are composed of multiple unknown substructures and side chains. Thus, FACs are difficult to be analyzed by traditional mass spectrometric methods. In this study, an integrated strategy was developed to global profiling and targeted structure annotation of FACs in complex matrix by LTQ Orbitrap. Dicarboxylic acid conjugated bufotoxins (DACBs) in Venenum bufonis (VB) were used as model compounds. The new strategy (abbreviated as HPNA) combined higher-energy C-trap dissociation (HCD) with product ion- (PI), neutral loss- (NL) based MSn (n ≥ 3) acquisition in both positive-ion mode and negative-ion mode. Several advantages are presented. First, various side chains were found under HCD in negative-ion mode, which included both known and unknown side chains. Second, DACBs with multiple side chains were simultaneously detected in one run. Compared with traditional quadrupole-based mass method, it greatly increased analysis throughput. Third, the fragment ions of side chain and steroids substructure could be obtained by PI- and NL-based MSn acquisition, respectively, which greatly increased the accuracy of the structure annotation of DACBs. In all, 78 DACBs have been discovered, of which 68 were new compounds; 25 types of substructure formulas and seven dicarboxylic acid side chains were found, especially five new side chains, including two saturated dicarboxylic acids [(azelaic acid (C9) and sebacic acid (C10)] and three unsaturated dicarboxylic acids (u-C8, u-C9, and u-C10). All these results greatly enriched the structures of DACBs in VB.

Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

PubMed Central

Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

1988-01-01

A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

Production of succinic Acid from citric Acid and related acids by lactobacillus strains.

PubMed

Kaneuchi, C; Seki, M; Komagata, K

1988-12-01

A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, alpha-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli.

Degree of branching in hyperbranched poly(glycerol-co-diacid)s synthesized in toluene

USDA-ARS?s Scientific Manuscript database

Hyperbranched polymers were synthesized by using a Lewis acid (dibutyltin(IV)oxide) to catalyze the polycondensation of glycerol with either succinic acid (n (aliphatic chain length)=2), glutaric acid (n=3) or azelaic acid (n=7) in toluene. These are the first examples of diacid-glycerol hyperbranc...

Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

NASA Astrophysics Data System (ADS)

Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

2016-03-01

Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

Efficacy of Lactic Acid, Lactic Acid-Acetic Acid Blends, and Peracetic Acid To Reduce Salmonella on Chicken Parts under Simulated Commercial Processing Conditions.

PubMed

Ramirez-Hernandez, Alejandra; Brashears, Mindy M; Sanchez-Plata, Marcos X

2018-01-01

The poultry processing industry has been undergoing a series of changes as it modifies processing practices to comply with new performance standards for chicken parts and comminuted poultry products. The regulatory approach encourages the use of intervention strategies to prevent and control foodborne pathogens in poultry products and thus improve food safety and protect human health. The present studies were conducted to evaluate the efficacy of antimicrobial interventions for reducing Salmonella on inoculated chicken parts under simulated commercial processing conditions. Chicken pieces were inoculated by immersion in a five-strain Salmonella cocktail at 6 log CFU/mL and then treated with organic acids and oxidizing agents on a commercial rinsing conveyor belt. The efficacy of spraying with six different treatments (sterile water, lactic acid, acetic acid, buffered lactic acid, acetic acid in combination with lactic acid, and peracetic acid) at two concentrations was evaluated on skin-on and skin-off chicken thighs at three application temperatures. Skinless chicken breasts were used to evaluate the antimicrobial efficacy of lactic acid and peracetic acid. The color stability of treated and untreated chicken parts was assessed after the acid interventions. The lactic acid and buffered lactic acid treatments produced the greatest reductions in Salmonella counts. Significant differences between the control and water treatments were identified for 5.11% lactic acid and 5.85% buffered lactic acid in both skin-on and skin-off chicken thighs. No significant effect of treatment temperature for skin-on chicken thighs was found. Lactic acid and peracetic acid were effective agents for eluting Salmonella cells attached to chicken breasts.

Preparation of the 3-monosulphates of cholic acid, chenodeoxycholic acid and deoxycholic acid.

PubMed Central

Haslewood, E S; Haslewood, G A

1976-01-01

1. The 3-sulphates of cholic, chenodeoxycholic and deoxycholic acids were prepared as crystalline disodium salts. 2. The method described shows that it is possible to prepare specific sulphate esters of polyhydroxy bile acids and to remove protecting acyl groups without removing the sulphate. 3. A study of bile acid sulphate solvolysis showed that none of the usual methods give the original bile acid in major yield in a single step. 4. An understanding of the preparation, properties and methods of solvolysis of bile acid sulphates is basic for investigations of cholestasis and liver disease. PMID:938488

Effect of acetic acid on citric acid fermentation in an integrated citric acid-methane fermentation process.

PubMed

Xu, Jian; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

2014-09-01

An integrated citric acid-methane fermentation process was proposed to solve the problem of extraction wastewater in citric acid fermentation process. Extraction wastewater was treated by anaerobic digestion and then recycled for the next batch of citric acid fermentation to eliminate wastewater discharge and reduce water resource consumption. Acetic acid as an intermediate product of methane fermentation was present in anaerobic digestion effluent. In this study, the effect of acetic acid on citric acid fermentation was investigated and results showed that lower concentration of acetic acid could promote Aspergillus niger growth and citric acid production. 5-Cyano-2,3-ditolyl tetrazolium chloride (CTC) staining was used to quantify the activity of A. niger cells, and the results suggested that when acetic acid concentration was above 8 mM at initial pH 4.5, the morphology of A. niger became uneven and the part of the cells' activity was significantly reduced, thereby resulting in deceasing of citric acid production. Effects of acetic acid on citric acid fermentation, as influenced by initial pH and cell number in inocula, were also examined. The result indicated that inhibition by acetic acid increased as initial pH declined and was rarely influenced by cell number in inocula.

Acid Rain, pH & Acidity: A Common Misinterpretation.

ERIC Educational Resources Information Center

Clark, David B.; Thompson, Ronald E.

1989-01-01

Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

Production of polymalic acid and malic acid by Aureobasidium pullulans fermentation and acid hydrolysis.

PubMed

Zou, Xiang; Zhou, Yipin; Yang, Shang-Tian

2013-08-01

Malic acid is a dicarboxylic acid widely used in the food industry and also a potential C4 platform chemical that can be produced from biomass. However, microbial fermentation for direct malic acid production is limited by low product yield, titer, and productivity due to end-product inhibition. In this work, a novel process for malic acid production from polymalic acid (PMA) fermentation followed by acid hydrolysis was developed. First, a PMA-producing Aureobasidium pullulans strain ZX-10 was screened and isolated. This microbe produced PMA as the major fermentation product at a high-titer equivalent to 87.6 g/L of malic acid and high-productivity of 0.61 g/L h in free-cell fermentation in a stirred-tank bioreactor. Fed-batch fermentations with cells immobilized in a fibrous-bed bioreactor (FBB) achieved the highest product titer of 144.2 g/L and productivity of 0.74 g/L h. The fermentation produced PMA was purified by adsorption with IRA-900 anion-exchange resins, achieving a ∼100% purity and a high recovery rate of 84%. Pure malic acid was then produced from PMA by hydrolysis with 2 M sulfuric acid at 85°C, which followed the first-order reaction kinetics. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application. Copyright © 2013 Wiley Periodicals, Inc.

Molecular and isotopic analyses of the hydroxy acids, dicarboxylic acids, and hydroxydicarboxylic acids of the Murchison meteorite

NASA Astrophysics Data System (ADS)

Cronin, J. R.; Pizzarello, S.; Epstein, S.; Krishnamurthy, R. V.

1993-10-01

The hydroxymonocarboxylic acids, dicarboxylic acids, and hydroxydicarboxylic acids of the Murchison meteorite were analyzed as their tert-butyldimethylsilyl derivatives using combined gas chromatography-mass spectrometry. The hydroxydicarboxylic acids have not been found previously in meteorites. Each class of compounds is numerous with carbon chains up to C8 or C9 and many, if not all, chain and substitution position isomers represented at each carbon number. The alpha-hydroxycarboxylic acids and alpha-hydroxydicarboxylic acids correspond structurally to many of the known meteoritic alpha-aminocarboxylic acids and alpha-aminodicarboxylic acids, a fact that supports the proposal that a Strecker synthesis was involved in the formation of both classes of compounds. Isotopic analyses show these acids to be D-rich relative to terrestrial organic compounds, as expected; however, the hydroxy acids appear to be isotopically lighter than the amino acids with respect to both carbon and hydrogen.

Aspartic acid

MedlinePlus

... we eat. Aspartic acid is also called asparaginic acid. Aspartic acid helps every cell in the body work. It ... release Normal nervous system function Plant sources of aspartic acid include: avocado, asparagus, and molasses. Animal sources of ...

Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, Luc

2003-06-24

A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

Constitutively Elevated Salicylic Acid Levels Alter Photosynthesis and Oxidative State but Not Growth in Transgenic Populus[C][W

PubMed Central

Xue, Liang-Jiao; Guo, Wenbing; Yuan, Yinan; Anino, Edward O.; Nyamdari, Batbayar; Wilson, Mark C.; Frost, Christopher J.; Chen, Han-Yi; Babst, Benjamin A.; Harding, Scott A.; Tsai, Chung-Jui

2013-01-01

Salicylic acid (SA) has long been implicated in plant responses to oxidative stress. SA overproduction in Arabidopsis thaliana leads to dwarfism, making in planta assessment of SA effects difficult in this model system. We report that transgenic Populus tremula × alba expressing a bacterial SA synthase hyperaccumulated SA and SA conjugates without negative growth consequences. In the absence of stress, endogenously elevated SA elicited widespread metabolic and transcriptional changes that resembled those of wild-type plants exposed to oxidative stress-promoting heat treatments. Potential signaling and oxidative stress markers azelaic and gluconic acids as well as antioxidant chlorogenic acids were strongly coregulated with SA, while soluble sugars and other phenylpropanoids were inversely correlated. Photosynthetic responses to heat were attenuated in SA-overproducing plants. Network analysis identified potential drivers of SA-mediated transcriptome rewiring, including receptor-like kinases and WRKY transcription factors. Orthologs of Arabidopsis SA signaling components NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1 and thioredoxins were not represented. However, all members of the expanded Populus nucleoredoxin-1 family exhibited increased expression and increased network connectivity in SA-overproducing Populus, suggesting a previously undescribed role in SA-mediated redox regulation. The SA response in Populus involved a reprogramming of carbon uptake and partitioning during stress that is compatible with constitutive chemical defense and sustained growth, contrasting with the SA response in Arabidopsis, which is transient and compromises growth if sustained. PMID:23903318

5-(Tetradecyloxy)-2-furancarboxylic acid and related hypolipidemic fatty acid-like alkyloxyarylcarboxylic acids.

PubMed

Parker, R A; Kariya, T; Grisar, J M; Petrow, V

1977-06-01

5-(Tetradecyloxy)-2-furancarboxylic acid (91, RMI 14514) was found to lower blood lipids and to inhibit fatty acid synthesis with minimal effects on liver weight and liver fat content. This fatty acid-like compound represents a new class of hypolipidemic agent; it is effective in rats and monkeys. The compound resulted from discovery of hypolipidemic activity in certain beta-keto esters, postulation and confirmation of the corresponding benzoic acids as active metabolites, and systematic exploration of the structure--activity relationships.

Acid Rain.

ERIC Educational Resources Information Center

Openshaw, Peter

1987-01-01

Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

Uracil in formic acid hydrolysates of deoxyribonucleic acid

PubMed Central

Schein, Arnold H.

1966-01-01

1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371

Interactions between F-111 Fuselage Fuel Tank Sealants. Part I. Characterisation of Polyester Sealants and their Hydrolytic Degradation Products,

DTIC Science & Technology

1983-12-01

maleic acid , adipic acid , azelaic acid and suberic acid . To ensure complete esterification during the exhaustive degradation reactions, an...spectroscopic techniques. Major components were shown to be sebacic acid and neopentyl glycol. The most significant difference between the two polyester...and acid equivalent weights of the prepolymers, their hydrolysis products and hydrolysed cured sealants were determined to assess extent of degradation

Aircraft measurement of dicarboxylic acids in the free tropospheric aerosols over the western to central North Pacific

NASA Astrophysics Data System (ADS)

Narukawa, M.; Kawamura, K.; Okada, K.; Zaizen, Y.; Makino, Y.

2003-07-01

Aircraft observation of aerosols was conducted in February 2000, for spatial and vertical distributions of dicarboxylic acids in the free troposphere over the western to central North Pacific. Oxalic, malonic, adipic and azelaic acids were detected in the aerosol samples as the major species. Concentrations of these diacids decreased exponentially with an increase in altitude. They were higher in the western North Pacific (130°E) and decrease eastward. Local flights conducted over Naha (Okinawa), Iwo-jima and Saipan showed that diacid concentrations decreased from the lower to upper troposphere. In the atmosphere over Saipan, where the air is not strongly affected from polluted East Asia, diacid concentrations were almost below the detection limit. Vertical profiles of diacids over Naha and Iwo-jima would be typical over the western North Pacific during winter, suggesting that diacids were significantly injected to the free troposphere from East Asia. Backward air mass trajectories also suggested that the diacids in the free troposphere over the North Pacific are strongly affected by the outflow from East Asia. Diacids, which were produced by both primary emission and secondary photochemical processes in polluted air of East Asia, could alter the physico-chemical properties of aerosols in the free troposphere over the western North Pacific.

Corrosion-Resistant Alkyd Coatings

DTIC Science & Technology

1992-02-18

molecule. Examples of such acid compounds include the aliphatic saturated dibasic acids such as succinic acid , adipic acid , azelaic acid , sebacic...of a benzoic acid . 15. SUBJECT TERMS corrosion control, single topcoat, one coat 16. SECURITY CLASSIFICATION OF: unclassified a. REPORT...consisting essentially of critical amounts of at least one zinc phos- phate, zinc molybdate and at least one zinc salt of a benzoic acid . 15

Distillation Separation of Hydrofluoric Acid and Nitric Acid from Acid Waste Using the Salt Effect on Vapor-Liquid Equilibrium

NASA Astrophysics Data System (ADS)

Yamamoto, Hideki; Sumoge, Iwao

2011-03-01

This study presents the distillation separation of hydrofluoric acid with use of the salt effect on the vapor-liquid equilibrium for acid aqueous solutions and acid mixtures. The vapor-liquid equilibrium of hydrofluoric acid + salt systems (fluorite, potassium nitrate, cesium nitrate) was measured using an apparatus made of perfluoro alkylvinylether. Cesium nitrate showed a salting-out effect on the vapor-liquid equilibrium of the hydrofluoric acid-water system. Fluorite and potassium nitrate showed a salting-in effect on the hydrofluoric acid-water system. Separation of hydrofluoric acid from an acid mixture containing nitric acid and hydrofluoric acid was tested by the simple distillation treatment using the salt effect of cesium nitrate (45 mass%). An acid mixture of nitric acid (5.0 mol · dm-3) and hydrofluoric acid (5.0 mol · dm-3) was prepared as a sample solution for distillation tests. The concentration of nitric acid in the first distillate decreased from 5.0 mol · dm-3 to 1.13 mol · dm-3, and the concentration of hydrofluoric acid increased to 5.41 mol · dm-3. This first distillate was further distilled without the addition of salt. The concentrations of hydrofluoric acid and nitric acid in the second distillate were 7.21 mol · dm-3 and 0.46 mol · dm-3, respectively. It was thus found that the salt effect on vapor-liquid equilibrium of acid mixtures was effective for the recycling of acids from acid mixture wastes.

Synthesis of new kojic acid based unnatural α-amino acid derivatives.

PubMed

Balakrishna, C; Payili, Nagaraju; Yennam, Satyanarayana; Uma Devi, P; Behera, Manoranjan

2015-11-01

An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond. Copyright © 2015 Elsevier Ltd. All rights reserved.

Process for the preparation of lactic acid and glyceric acid

DOEpatents

Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

2008-12-02

Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

Short chain fatty acids (butyric acid) and intestinal diseases

PubMed

Manrique Vergara, David; González Sánchez, María Eugenia

2017-10-15

Short chain fatty acids contain up to 6 carbon atoms. Among them, butyric acid stands out for its key role in pathologies with intestinal affectation. Butyric acid is the main energetic substrate of the colonocyte, it stimulates the absorption of sodium and water in the colon, and presents trophic action on the intestinal cells. To review the clinical use of formulations for the oral use of butyric acid. Review of published articles on oral supplementation with butyric acid in intestinal pathologies. The publications mainly deal with the use of oral butyric acid in pathologies involving inflammation and / or alterations of intestinal motility. Highlighting the clinical potential in inflammatory bowel diseases and irritable bowel syndrome. The use of oral supplementation with butyric acid is a promising strategy in pathologies such as inflammatory bowel diseases and irritable bowel syndrome. Bio-available butyric acid formulations with acceptable organoleptic characteristics are being advanced.

The bile acids, deoxycholic acid and ursodeoxycholic acid, regulate colonic epithelial wound healing.

PubMed

Mroz, Magdalena S; Lajczak, Natalia K; Goggins, Bridie J; Keely, Simon; Keely, Stephen J

2018-03-01

The intestinal epithelium constitutes an innate barrier which, upon injury, undergoes self-repair processes known as restitution. Although bile acids are known as important regulators of epithelial function in health and disease, their effects on wound healing processes are not yet clear. Here we set out to investigate the effects of the colonic bile acids, deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA), on epithelial restitution. Wound healing in T 84 cell monolayers grown on transparent, permeable supports was assessed over 48 h with or without bile acids. Cell migration was measured in Boyden chambers. mRNA and protein expression were measured by RT-PCR and Western blotting. DCA (50-150 µM) significantly inhibited wound closure in cultured epithelial monolayers and attenuated cell migration in Boyden chamber assays. DCA also induced nuclear accumulation of the farnesoid X receptor (FXR), whereas an FXR agonist, GW4064 (10 µM), inhibited wound closure. Both DCA and GW4064 attenuated the expression of CFTR Cl - channels, whereas inhibition of CFTR activity with either CFTR- inh -172 (10 µM) or GlyH-101 (25 µM) also prevented wound healing. Promoter/reporter assays revealed that FXR-induced downregulation of CFTR is mediated at the transcriptional level. In contrast, UDCA (50-150 µM) enhanced wound healing in vitro and prevented the effects of DCA. Finally, DCA inhibited and UDCA promoted mucosal healing in an in vivo mouse model. In conclusion, these studies suggest bile acids are important regulators of epithelial wound healing and are therefore good targets for development of new drugs to modulate intestinal barrier function in disease treatment. NEW & NOTEWORTHY The secondary bile acid, deoxycholic acid, inhibits colonic epithelial wound healing, an effect which appears to be mediated by activation of the nuclear bile acid receptor, FXR, with subsequent downregulation of CFTR expression and activity. In contrast, ursodeoxycholic acid promotes

On the acid-base properties of humic acid in soil.

PubMed

Cooke, James D; Hamilton-Taylor, John; Tipping, Edward

2007-01-15

Humic acid was isolated from three contrasting organic-rich soils and acid-base titrations performed over a range of ionic strengths. Results obtained were unlike most humic acid data sets; they showed a greater ionic strength dependency at low pH than at high pH. Forward- and back-titrations with the base and acid revealed hysteresis, particularly at low pH. Previous authors attributed this type of hysteresis to humic acid aggregates-created during the isolation procedure-being redissolved during titration as the pH increased and regarded the results as artificial. However, forward- and back-titrations with organic-rich soils also demonstrated a similar hysteretic behavior. These observations indicate (i) that titrations of humic acid in aggregated form (as opposed to the more usual dissolved form) are more representative of the acid-base properties of humic acid in soil and (ii) that the ionic strength dependency of proton binding in humic acid is related to its degree of aggregation. Thus, the current use of models based on data from dissolved humic substances to predictthe acid-base properties of humic acid in soil under environmental conditions may be flawed and could substantially overestimate their acid buffering capacity.

Effects of dietary conjugated linoleic acid and linoleic:linolenic acid ratio on polyunsaturated fatty acid status in laying hens.

PubMed

Du, M; Ahn, D U; Sell, J L

2000-12-01

A study was conducted to determine the effects of dietary conjugated linoleic acid (CLA) and the ratio of linoleic:linolenic acid on long-chain polyunsaturated fatty acid status. Thirty-two 31-wk-old White Leghorn hens were randomly assigned to four diets containing 8.2% soy oil, 4.1% soy oil + 2.5% CLA (4.1% CLA source), 4.1% flax oil + 2.5% CLA, or 4.1% soy oil + 4.1% flax oil. Hens were fed the diets for 3 wk before eggs and tissues were collected for the study. Lipids were extracted from egg yolk and tissues, classes of egg yolk lipids were separated, and fatty acid concentrations of total lipids, triglyceride, phosphatidylethanolamine, and phosphatidylcholine were analyzed by gas chromatography. The concentrations of monounsaturated fatty acids and non-CLA polyunsaturated fatty acids were reduced after CLA feeding. The amount of arachidonic acid was decreased after CLA feeding in linoleic acid- and linolenic acid-rich diets, but amounts of eicosapentaenoic acid and docosahexaenoic acid were increased in the linolenic-rich diet, indicating that the synthesis or deposition of long-chain n-3 fatty acids was accelerated after CLA feeding. The increased docosahexaenoic acid and eicosapentaenoic acid contents in lipid may be compensation for the decreased arachidonic acid content. Dietary supplementation of linoleic acid increased n-6 fatty acid levels in lipids, whereas linolenic acid increased n-3 fatty acid levels. Results also suggest that CLA might not be elongated to synthesize long-chain fatty acids in significant amounts. The effect of CLA in reducing the level of n-6 fatty acids and promoting the level of n-3 fatty acids could be related to the biological effects of CLA.

Long-term trend of dicarboxylic acids, ketoacids and dicarbonyls in the marine aerosols over the western North Pacific in 2001-2006

NASA Astrophysics Data System (ADS)

Kawamura, K.; Tachibana, E.; Mochida, M.

2006-12-01

To understand a long-range atmospheric transport of water-soluble organics in the western North Pacific, remote marine aerosols were collected on weekly basis at a subtropical island (Chichijima, 142E; 27N) from 2001 to 2006 using a high volume air sampler and pre-combusted quartz filter. The island is located in the boundary of westerly and trade wind regimes. The aerosols were analyzed for dicarboxylic acids, ketoacids and dicarbonyls employing butyl ester derivatization followed by GC determination. Homologous saturated diacids (C2-C11) were detected with a predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids as well as unsaturated diacids, including maleic (M), fumaric (F), phthalic acids. Ketoacids and dicarbonyls were also detected. Concentrations of total diacids fluctuated significantly in a range of 10-600 ngm-3 with winter/spring maximum and summer minimum. The winter/spring maximum can be explained by a combinattion of enhanced emissions of polluted aerosols and their precursors in Asia and the intensified westerlies over the North Pacific in the season. Seasonal trends of the molecular compositions were also found. For example, concentration ratios of C3 to C4 acid showed a maximum in summer, indicating more oxidation of longer-chain diacids to shorter ones. M/F ratios increased from summer to winter as a result of photochemically-induced isomerization of cis and trans configuration of unsaturated diacids. On the other hand, azelaic acid (C9) relative to other diacids showed a sharp increase in summer. Because C9 is a specific photo-oxidation product of unsaturated fatty acid such as oleic acid, this demonstrates an enhanced sea-to- air emission of unsaturated fatty acids in summer followed by photochemical oxidation. Long-term trends of diacids and related compounds in the aerosols will be discussed for 2001 to 2006. The results will also be compared with those obtained at the same site for 1990 to 1993 to detect long

The fatty acid-rich fraction of Eruca sativa (rocket salad) leaf extract exerts antidiabetic effects in cultured skeletal muscle, adipocytes and liver cells.

PubMed

Hetta, Mona H; Owis, Asmaa I; Haddad, Pierre S; Eid, Hoda M

2017-12-01

Eruca sativa Mill. (Brassicaceae), commonly known as rocket salad, is a popular leafy-green vegetable with many health benefits. To evaluate the antidiabetic activities of this plant in major insulin-responsive tissues. Five E. sativa leaf extracts of varying polarity were prepared (aqueous extract, 70% and 95% ethanol extracts, the n-hexane-soluble fraction of the 95% ethanol extract (ES3) and the defatted 95% ethanol extract). Eruca sativa extracts were investigated through a variety of cell-based in vitro bioassays for antidiabetic activities in C2C12 skeletal muscle cells, H4IIE hepatocytes and 3T3-L1 adipocytes. Guided by the results of these bioassays, ES3 was fractionated into the saponifiable (SM) and the unspaonifiable (USM) fractions. Glucose uptake was measured using [ 3 H]-deoxy-glucose, while the effects on hepatic glucose-6-phosphatase (G6Pase) and adipogenesis were assessed using Wako AutoKit Glucose and AdipoRed assays, respectively. ES3 and its SM fraction significantly stimulated glucose uptake with EC 50 values of 8.0 and 5.8 μg/mL, respectively. Both extracts significantly inhibited G6Pase activity (IC 50 values of 4.8 and 9.3 μg/mL, respectively). Moreover, ES3 and SM showed significant adipogenic activities with EC 50 of 4.3 and 6.1 μg/mL, respectively. Fatty acid content of SM was identified by GC-MS. trans-Vaccenic and palmitoleic acids were the major unsaturated fatty acids, while palmitic and azelaic acids were the main saturated fatty acids. These findings indicate that ES3 and its fatty acid-rich fraction exhibit antidiabetic activities in insulin-responsive cell lines and may hence prove useful for the treatment of type 2 diabetes.

Quantitation of monomers in poly(glyerol-co-diacid) gels using gas chromatography

USDA-ARS?s Scientific Manuscript database

The validation of a gas chromatography (GC) method developed to quantify amounts of starting material from the synthesis of hyperbranched polymers made from glycerol and either succinic acid, glutaric acid, or azelaic acid is described. The GC response to concentration was linear for all starting r...

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, Luc

1999-01-01

A process of preparing an acid addition salt of delta-aminolevulinic acid comprising: dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures thereof to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing said alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Understanding Acid Rain

ERIC Educational Resources Information Center

Damonte, Kathleen

2004-01-01

The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

DOEpatents

Moens, L.

1999-05-25

A process is disclosed for preparing an acid addition salt of delta-aminolevulinic acid comprising. The process involves dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing the alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Validation of a multi-analyte HPLC-DAD method for determination of uric acid, creatinine, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid and 2-methylhippuric acid in human urine.

PubMed

Remane, Daniela; Grunwald, Soeren; Hoeke, Henrike; Mueller, Andrea; Roeder, Stefan; von Bergen, Martin; Wissenbach, Dirk K

2015-08-15

During the last decades exposure sciences and epidemiological studies attracts more attention to unravel the mechanisms for the development of chronic diseases. According to this an existing HPLC-DAD method for determination of creatinine in urine samples was expended for seven analytes and validated. Creatinine, uric acid, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid, and 2-methylhippuric acid were separated by gradient elution (formate buffer/methanol) using an Eclipse Plus C18 Rapid Resolution column (4.6mm×100mm). No interfering signals were detected in mobile phase. After injection of blank urine samples signals for the endogenous compounds but no interferences were detected. All analytes were linear in the selected calibration range and a non weighted calibration model was chosen. Bias, intra-day and inter-day precision for all analytes were below 20% for quality control (QC) low and below 10% for QC medium and high. The limits of quantification in mobile phase were in line with reported reference values but had to be adjusted in urine for homovanillic acid (45mg/L), niacinamide 58.5(mg/L), and indole-3-acetic acid (63mg/L). Comparison of creatinine data obtained by the existing method with those of the developed method showing differences from -120mg/L to +110mg/L with a mean of differences of 29.0mg/L for 50 authentic urine samples. Analyzing 50 authentic urine samples, uric acid, creatinine, hippuric acid, and 2-methylhippuric acid were detected in (nearly) all samples. However, homovanillic acid was detected in 40%, niacinamide in 4% and indole-3-acetic acid was never detected within the selected samples. Copyright © 2015 Elsevier B.V. All rights reserved.

A GC-ECD method for estimation of free and bound amino acids, gamma-aminobutyric acid, salicylic acid, and acetyl salicylic acid from Solanum lycopersicum (L.).

PubMed

Meher, Hari Charan; Gajbhiye, Vijay T; Singh, Ghanendra

2011-01-01

A gas chromatograph with electron capture detection method for estimation of selected metabolites--amino acids (free and bound), gamma-aminobutyric acid (GABA), salicylic acid (SA), and acetyl salicylic acid (ASA) from tomato--is reported. The method is based on nitrophenylation of the metabolites by 1-fluoro-2, 4-dinitrobenzene under aqueous alkaline conditions to form dinitophenyl derivatives. The derivatives were stable under the operating conditions of GC. Analysis of bound amino acids comprised perchloric acid precipitation of protein, alkylation (carboxymethylation) with iodoacetic acid, vapor-phase hydrolysis, and derivatization with 1-fluoro-2,4-dinitrobenzene in that order. The metabolites were resolved in 35 min, using a temperature-programmed run. The method is rapid, sensitive, and precise. It easily measured the typical amino acids (aspartate, asparagine, glutamate, glutamine, alanine, leucine, lysine, and phenylalanine) used for identification and quantification of a protein, resolved amino acids of the same mass (leucine and isoleucine), satisfactorily measured sulfur amino acid (methionine, cystine, and cysteine), and quantified GABA, SA, and ASA, as well. The developed method was validated for specificity, linearity, and precision. It has been applied and recommended for estimation of 25 metabolites from Solanum lycopersicum (L.).

Targeted metabolomics analysis reveals the association between maternal folic acid supplementation and fatty acids and amino acids profiles in rat pups.

PubMed

Liu, Zhipeng; Liu, Rui; Chou, Jing; Yu, Jiaying; Liu, Xiaowei; Sun, Changhao; Li, Ying; Liu, Liyan

2018-07-15

Maternal diet during pregnancy can influence offspring's health by affecting development and metabolism. This study aimed to analyze the influence of maternal folic acid (FA) supplementation on the metabolism of rat pups using targeted metabolomics. Twenty female rats were randomly assigned to a FA supplementation (FAS group, n = 10) or control group (n = 10), which were fed AIN93G diet with 2 or 10 mg/kg FA, respectively. We then measured amino acids and their derivatives, biogenic amines, and fatty acids in the female rats and their pups by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC/MS-MS) and gas chromatography-mass spectrometry (GC/MS-MS). In maternal rats, the significant changes of three metabolites (proline, γ-aminobutyric acid and esterified octadecatetraenoic acid, P < 0.05) were observed in FAS group. For the rat pups, FAS pups had significantly lower homocysteine and higher FA levels than control pups. The lower levels of amino acids (leucine, isoleucine, serine, proline) were obtained in FAS pups. Furthermore, there were the decreased esterified fatty acids (arachidonic acid, eicosapentaenoic acid, and docosatetraenoic acid) and free fatty acids (oleic acid, linoleic acid, γ-linolenic acid, octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid and selacholeic acid) in FAS pups. Metabolic changes in the FAS pups were characterized by changes in fatty acids and amino acids. These results suggested that FA supplementation during pregnancy influenced amino acids and fatty acids metabolism in rat pups. This study provides new insights into the regulation of amino acids and fatty acids metabolism during early life. Copyright © 2018 Elsevier B.V. All rights reserved.

All-trans retinoic acid regulates hepatic bile acid homeostasis

PubMed Central

Yang, Fan; He, Yuqi; Liu, Hui-Xin; Tsuei, Jessica; Jiang, Xiaoyue; Yang, Li; Wang, Zheng-Tao; Wan, Yu-Jui Yvonne

2014-01-01

Retinoic acid (RA) and bile acids share common roles in regulating lipid homeostasis and insulin sensitivity. In addition, the receptor for RA (retinoid x receptor) is a permissive partner of the receptor for bile acids, farnesoid x receptor (FXR/NR1H4). Thus, RA can activate the FXR-mediated pathway as well. The current study was designed to understand the effect of all-trans RA on bile acid homeostasis. Mice were fed an all-trans RA-supplemented diet and the expression of 46 genes that participate in regulating bile acid homeostasis was studied. The data showed that all-trans RA has a profound effect in regulating genes involved in synthesis and transport of bile acids. All-trans RA treatment reduced the gene expression levels of Cyp7a1, Cyp8b1, and Akr1d1, which are involved in bile acid synthesis. All-trans RA also decreased the hepatic mRNA levels of Lrh-1 (Nr5a2) and Hnf4α (Nr2a1), which positively regulate the gene expression of Cyp7a1 and Cyp8b1. Moreover, all-trans RA induced the gene expression levels of negative regulators of bile acid synthesis including hepatic Fgfr4, Fxr, and Shp (Nr0b2) as well as ileal Fgf15. All-trans RA also decreased the expression of Abcb11 and Slc51b, which have a role in bile acid transport. Consistently, all-trans RA reduced hepatic bile acid levels and the ratio of CA/CDCA, as demonstrated by liquid chromatography-mass spectrometry. The data suggest that all-trans RA-induced SHP may contribute to the inhibition of CYP7A1 and CYP8B1, which in turn reduces bile acid synthesis and affects lipid absorption in the gastrointestinal tract. PMID:25175738

Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

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

Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher

An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted inmore » liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.« less

Trans-hemispheric contribution of C2-C10 α, ω-dicarboxylic acids, and related polar compounds to water-soluble organic carbon in the western Pacific aerosols in relation to photochemical oxidation reactions

NASA Astrophysics Data System (ADS)

SempéRé, Richard; Kawamura, Kimitaka

2003-06-01

Marine aerosol samples were collected during a western Pacific cruise covering the latitude range between 35°N and 40°S (140°E-180°E). They were analyzed for total carbon (TC), total nitrogen (TN), water-soluble organic carbon (WSOC) along with the molecular distributions of C2-C10 α, ω-dicarboxylic acids, and related polar compounds, mainly, ω-oxocarboxylic acids (C2-C9) and α-dicarbonyls (C2-C3). Oxalic acid (C2) was the most abundant followed by malonic (C3) and succinic (C4) acids. The total diacid concentration range was 7-605 ng m-3 (av. 85 ng m-3) and the diacid-carbon accounted for 2-15% (average 8%) of WSOC which comprised 29-55% (average 40%) of TC. Dry depositions of total diacids over the northern and southern Pacific Ocean were estimated to be 256-1907 μg m-2 yr-1 (average 735; n = 4) and 22-396 μg m-2 yr-1 (average 134; n = 14), respectively, whereas the air-to-sea flux of oxalic acid was 18-1351 μg m-2 yr-1 (average 466 μg m-2 yr-1) and 7.5-275 μg m-2 yr-1 (average 75 μg m-2 yr-1) in the Northern and Southern Hemispheres. We observed that the concentration ratios of diacid-C/WSOC, azelaic acid (C9)/ω-oxononanoic acid, maleic acid (iC4cis)/fumaric (iC4trans) acid and succinic acid (C4)/total diacids were correlated with air temperature. These findings showed that the intensity of photochemical oxidation reactions and thus the variation in sunlight intensity characterized here by air temperature, significantly control the molecular distribution of water-soluble organic compounds during the long-range transport of anthropogenic and/or biogenic higher molecular weight organic compounds.

Acid Earth--The Global Threat of Acid Pollution.

ERIC Educational Resources Information Center

McCormick, John

Acid pollution is a major international problem, but the debate it has elicited has often clouded the distinction between myth and facts. This publication attempts to concerning the acid pollution situation. This publication attempts to identify available facts. It is the first global review of the problem of acid pollution and the first to…

Parabanic acid is the singlet oxygen specific oxidation product of uric acid.

PubMed

Iida, Sayaka; Ohkubo, Yuki; Yamamoto, Yorihiro; Fujisawa, Akio

2017-11-01

Uric acid quenches singlet oxygen physically or reacts with it, but the oxidation product has not been previously characterized. The present study determined that the product is parabanic acid, which was confirmed by LC/TOFMS analysis. Parabanic acid was stable at acidic pH (<5.0), but hydrolyzed to oxaluric acid at neutral or alkaline pH. The total yields of parabanic acid and oxaluric acid based on consumed uric acid were ~100% in clean singlet oxygen production systems such as UVA irradiation of Rose Bengal and thermal decomposition of 3-(1,4-dihydro-1,4-epidioxy-4-methyl-1-naphthyl)propionic acid. However, the ratio of the amount of uric acid consumed to the total amount of singlet oxygen generated was less than 1/180, indicating that most of the singlet oxygen was physically quenched. The total yields of parabanic acid and oxaluric acid were high in the uric acid oxidation systems with hydrogen peroxide plus hypochlorite or peroxynitrite. They became less than a few percent in peroxyl radical-, hypochlorite- or peroxynitrite-induced oxidation of uric acid. These results suggest that parabanic acid could be an in vivo probe of singlet oxygen formation because of the wide distribution of uric acid in human tissues and extracellular spaces. In fact, sunlight exposure significantly increased human skin levels of parabanic acid.

Crystal growth and physical characterization of picolinic acid cocrystallized with dicarboxylic acids

NASA Astrophysics Data System (ADS)

Somphon, Weenawan; Haller, Kenneth J.

2013-01-01

Pharmaceutical cocrystals are multicomponent materials containing an active pharmaceutical ingredient with another component in well-defined stoichiometry within the same unit cell. Such cocrystals are important in drug design, particularly for improving physicochemical properties such as solubility, bioavailability, or chemical stability. Picolinic acid is an endogenous metabolite of tryptophan and is widely used for neuroprotective, immunological, and anti-proliferative effects within the body. In this paper we present cocrystallization experiments of a series of dicarboxylic acids, oxalic acid, succinic acid, DL-tartaric acid, pimelic acid, and phthalic acid, with picolinic acid. Characterization by FT-IR and Raman spectroscopy, DSC and TG/DTG analysis, and X-ray powder diffraction show that new compounds are formed, including a 1:1 picolinium tartrate monohydrate, a 2:1 monohydrate adduct of picolinic acid and oxalic acid, and a 2:1 picolinic acid-succinic acid monohydrate cocrystal.

40 CFR 721.3620 - Fatty acid amine condensate, polycarboxylic acid salts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid amine condensate... Specific Chemical Substances § 721.3620 Fatty acid amine condensate, polycarboxylic acid salts. (a... a fatty acid amine condensate, polycarboxylic acid salts. (PMN P-92-445) is subject to reporting...

40 CFR 721.3620 - Fatty acid amine condensate, polycarboxylic acid salts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acid amine condensate... Specific Chemical Substances § 721.3620 Fatty acid amine condensate, polycarboxylic acid salts. (a... a fatty acid amine condensate, polycarboxylic acid salts. (PMN P-92-445) is subject to reporting...

A novel approach in acidic disinfection through inhibition of acid resistance mechanisms; Maleic acid-mediated inhibition of glutamate decarboxylase activity enhances acid sensitivity of Listeria monocytogenes.

PubMed

Paudyal, Ranju; Barnes, Ruth H; Karatzas, Kimon Andreas G

2018-02-01

Here it is demonstrated a novel approach in disinfection regimes where specific molecular acid resistance systems are inhibited aiming to eliminate microorganisms under acidic conditions. Despite the importance of the Glutamate Decarboxylase (GAD) system for survival of Listeria monocytogenes and other pathogens under acidic conditions, its potential inhibition by specific compounds that could lead to its elimination from foods or food preparation premises has not been studied. The effects of maleic acid on the acid resistance of L. monocytogenes were investigated and found that it has a higher antimicrobial activity under acidic conditions than other organic acids, while this could not be explained by its pKa or Ka values. The effects were found to be more pronounced on strains with higher GAD activity. Maleic acid affected the extracellular GABA levels while it did not affect the intracellular ones. Maleic acid had a major impact mainly on GadD2 activity as also shown in cell lysates. Furthermore, it was demonstrated that maleic acid is able to partly remove biofilms of L. monocytogenes. Maleic acid is able to inhibit the GAD of L. monocytogenes significantly enhancing its sensitivity to acidic conditions and together with its ability to remove biofilms, make a good candidate for disinfection regimes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bifidobacterium breve with α-linolenic acid and linoleic acid alters fatty acid metabolism in the maternal separation model of irritable bowel syndrome.

PubMed

Barrett, Eoin; Fitzgerald, Patrick; Dinan, Timothy G; Cryan, John F; Ross, R Paul; Quigley, Eamonn M; Shanahan, Fergus; Kiely, Barry; Fitzgerald, Gerald F; O'Toole, Paul W; Stanton, Catherine

2012-01-01

The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15) were orally gavaged with either B. breve DPC6330 (10(9) microorganisms/day) alone or in combination with 0.5% (w/w) linoleic acid & 0.5% (w/w) α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11) in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (p<0.05). Administration of B. breve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11) in adipose tissue and palmitoleic acid in the prefrontal cortex (p<0.05), whereas feeding B. breve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (p<0.05) compared with the NS un-supplemented controls. Administration of B. breve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (p<0.01) and α-linolenic acid in adipose tissue (p<0.001), whereas feeding B. breve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (p<0.05), and α-linolenic acid in adipose tissue (p<0.001). B. breve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated rats

Bifidobacterium breve with α-Linolenic Acid and Linoleic Acid Alters Fatty Acid Metabolism in the Maternal Separation Model of Irritable Bowel Syndrome

PubMed Central

Barrett, Eoin; Fitzgerald, Patrick; Dinan, Timothy G.; Cryan, John F.; Ross, R. Paul; Quigley, Eamonn M.; Shanahan, Fergus; Kiely, Barry; Fitzgerald, Gerald F.; O'Toole, Paul W.; Stanton, Catherine

2012-01-01

The aim of this study was to compare the impact of dietary supplementation with a Bifidobacterium breve strain together with linoleic acid & α-linolenic acid, for 7 weeks, on colonic sensitivity and fatty acid metabolism in rats. Maternally separated and non-maternally separated Sprague Dawley rats (n = 15) were orally gavaged with either B. breve DPC6330 (109 microorganisms/day) alone or in combination with 0.5% (w/w) linoleic acid & 0.5% (w/w) α-linolenic acid, daily for 7 weeks and compared with trehalose and bovine serum albumin. Tissue fatty acid composition was assessed by gas-liquid chromatography and visceral hypersensitivity was assessed by colorectal distension. Significant differences in the fatty acid profiles of the non-separated controls and maternally separated controls were observed for α-linolenic acid and arachidonic acid in the liver, oleic acid and eicosenoic acid (c11) in adipose tissue, and for palmitoleic acid and docosahexaenoic acid in serum (p<0.05). Administration of B. breve DPC6330 to MS rats significantly increased palmitoleic acid, arachidonic acid and docosahexaenoic acid in the liver, eicosenoic acid (c11) in adipose tissue and palmitoleic acid in the prefrontal cortex (p<0.05), whereas feeding B. breve DPC6330 to non separated rats significantly increased eicosapentaenoic acid and docosapentaenoic acid in serum (p<0.05) compared with the NS un-supplemented controls. Administration of B. breve DPC6330 in combination with linoleic acid and α-linolenic acid to maternally separated rats significantly increased docosapentaenoic acid in the serum (p<0.01) and α-linolenic acid in adipose tissue (p<0.001), whereas feeding B. breve DPC6330 with fatty acid supplementation to non-separated rats significantly increased liver and serum docosapentaenoic acid (p<0.05), and α-linolenic acid in adipose tissue (p<0.001). B. breve DPC6330 influenced host fatty acid metabolism. Administration of B. breve DPC6330 to maternally separated rats

Aminocaproic Acid and Tranexamic Acid Fail to Reverse Dabigatran-Induced Coagulopathy.

PubMed

Levine, Michael; Huang, Margaret; Henderson, Sean O; Carmelli, Guy; Thomas, Stephen H

In recent years, dabigatran has emerged as a popular alternative to warfarin for treatment of atrial fibrillation. If rapid reversal is required, however, no reversal agent has clearly been established. The primary purpose of this manuscript was to evaluate the efficacy of tranexamic acid and aminocaproic acid as agents to reverse dabigatran-induced coagulopathy. Rats were randomly assigned to 6 groups. Each rat received either dabigatran or oral placebo, followed by saline, tranexamic acid, or aminocaproic acid. An activated clotting test was used to measure the coagulopathy. Neither tranexamic acid nor aminocaproic acid successfully reversed dabigatran-induced coagulopathy. In this rodent model of dabigatran-induced coagulopathy, neither tranexamic acid nor aminocaproic acid were able to reverse the coagulopathy.

Usnic acid.

PubMed

Ingólfsdóttir, K

2002-12-01

Since its first isolation in 1844, usnic acid [2,6-diacetyl-7,9-dihydroxy-8,9b-dimethyl-1,3(2H,9bH)-dibenzo-furandione] has become the most extensively studied lichen metabolite and one of the few that is commercially available. Usnic acid is uniquely found in lichens, and is especially abundant in genera such as Alectoria, Cladonia, Usnea, Lecanora, Ramalina and Evernia. Many lichens and extracts containing usnic acid have been utilized for medicinal, perfumery, cosmetic as well as ecological applications. Usnic acid as a pure substance has been formulated in creams, toothpaste, mouthwash, deodorants and sunscreen products, in some cases as an active principle, in others as a preservative. In addition to antimicrobial activity against human and plant pathogens, usnic acid has been shown to exhibit antiviral, antiprotozoal, antiproliferative, anti-inflammatory and analgesic activity. Ecological effects, such as antigrowth, antiherbivore and anti-insect properties, have also been demonstrated. A difference in biological activity has in some cases been observed between the two enantiomeric forms of usnic acid. Recently health food supplements containing usnic acid have been promoted for use in weight reduction, with little scientific support. The emphasis of the current review is on the chemistry and biological activity of usnic acid and its derivatives in addition to rational and ecologically acceptable methods for provision of this natural compound on a large scale.

Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

NASA Technical Reports Server (NTRS)

Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

1992-01-01

Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

Microarray-based transcriptome of Listeria monocytogenes adapted to sublethal concentrations of acetic acid, lactic acid, and hydrochloric acid.

PubMed

Tessema, Girum Tadesse; Møretrø, Trond; Snipen, Lars; Heir, Even; Holck, Askild; Naterstad, Kristine; Axelsson, Lars

2012-09-01

Listeria monocytogenes , an important foodborne pathogen, commonly encounters organic acids in food-related environments. The transcriptome of L. monocytogenes L502 was analyzed after adaptation to pH 5 in the presence of acetic acid, lactic acid, or hydrochloric acid (HCl) at 25 °C, representing a condition encountered in mildly acidic ready-to-eat food kept at room temperature. The acid-treated cells were compared with a reference culture with a pH of 6.7 at the time of RNA harvesting. The number of genes and magnitude of transcriptional responses were higher for the organic acids than for HCl. Protein coding genes described for low pH stress, energy transport and metabolism, virulence determinates, and acid tolerance response were commonly regulated in the 3 acid-stressed cultures. Interestingly, the transcriptional levels of histidine and cell wall biosynthetic operons were upregulated, indicating possible universal response against low pH stress in L. monocytogenes. The opuCABCD operon, coding proteins for compatible solutes transport, and the transcriptional regulator sigL were significantly induced in the organic acids, strongly suggesting key roles during organic acid stress. The present study revealed the complex transcriptional responses of L. monocytogenes towards food-related acidulants and opens the roadmap for more specific and in-depth future studies.

21 CFR 172.350 - Fumaric acid and salts of fumaric acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Fumaric acid and salts of fumaric acid. 172.350... HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.350 Fumaric acid and salts of fumaric acid. Fumaric acid and its calcium, ferrous, magnesium, potassium, and sodium salts may be safely used...

Vibrational structure of the polyunsaturated fatty acids eicosapentaenoic acid and arachidonic acid studied by infrared spectroscopy

NASA Astrophysics Data System (ADS)

Kiefer, Johannes; Noack, Kristina; Bartelmess, Juergen; Walter, Christian; Dörnenburg, Heike; Leipertz, Alfred

2010-02-01

The spectroscopic discrimination of the two structurally similar polyunsaturated C 20 fatty acids (PUFAs) 5,8,11,14,17-eicosapentaenoic acid and 5,8,11,14-eicosatetraenoic acid (arachidonic acid) is shown. For this purpose their vibrational structures are studied by means of attenuated total reflection (ATR) Fourier-transform infrared (FT-IR) spectroscopy. The fingerprint regions of the recorded spectra are found to be almost identical, while the C-H stretching mode regions around 3000 cm -1 show such significant differences as results of electronic and molecular structure alterations based on the different degree of saturation that both fatty acids can be clearly distinguished from each other.

Docosahexaenoic Acid-Derived Fatty Acid Esters of Hydroxy Fatty Acids (FAHFAs) With Anti-inflammatory Properties.

PubMed

Kuda, Ondrej; Brezinova, Marie; Rombaldova, Martina; Slavikova, Barbora; Posta, Martin; Beier, Petr; Janovska, Petra; Veleba, Jiri; Kopecky, Jan; Kudova, Eva; Pelikanova, Terezie; Kopecky, Jan

2016-09-01

White adipose tissue (WAT) is a complex organ with both metabolic and endocrine functions. Dysregulation of all of these functions of WAT, together with low-grade inflammation of the tissue in obese individuals, contributes to the development of insulin resistance and type 2 diabetes. n-3 polyunsaturated fatty acids (PUFAs) of marine origin play an important role in the resolution of inflammation and exert beneficial metabolic effects. Using experiments in mice and overweight/obese patients with type 2 diabetes, we elucidated the structures of novel members of fatty acid esters of hydroxy fatty acids-lipokines derived from docosahexaenoic acid (DHA) and linoleic acid, which were present in serum and WAT after n-3 PUFA supplementation. These compounds contained DHA esterified to 9- and 13-hydroxyoctadecadienoic acid (HLA) or 14-hydroxydocosahexaenoic acid (HDHA), termed 9-DHAHLA, 13-DHAHLA, and 14-DHAHDHA, and were synthesized by adipocytes at concentrations comparable to those of protectins and resolvins derived from DHA in WAT. 13-DHAHLA exerted anti-inflammatory and proresolving properties while reducing macrophage activation by lipopolysaccharides and enhancing the phagocytosis of zymosan particles. Our results document the existence of novel lipid mediators, which are involved in the beneficial anti-inflammatory effects attributed to n-3 PUFAs, in both mice and humans. © 2016 by the American Diabetes Association.

Decomposition mechanism of chromite in sulfuric acid-dichromic acid solution

NASA Astrophysics Data System (ADS)

Zhao, Qing; Liu, Cheng-jun; Li, Bao-kuan; Jiang, Mao-fa

2017-12-01

The sulfuric acid leaching process is regarded as a promising, cleaner method to prepare trivalent chromium products from chromite; however, the decomposition mechanism of the ore is poorly understood. In this work, binary spinels of Mg-Al, Mg-Fe, and Mg-Cr in the powdered and lump states were synthesized and used as raw materials to investigate the decomposition mechanism of chromite in sulfuric acid-dichromic acid solution. The leaching yields of metallic elements and the changes in morphology of the spinel were studied. The experimental results showed that the three spinels were stable in sulfuric acid solution and that dichromic acid had little influence on the decomposition behavior of the Mg-Al spinel and Mg-Fe spinel because Mg2+, Al3+, and Fe3+ in spinels cannot be oxidized by Cr6+. However, in the case of the Mg-Cr spinel, dichromic acid substantially promoted the decomposition efficiency and functioned as a catalyst. The decomposition mechanism of chromite in sulfuric acid-dichromic acid solution was illustrated on the basis of the findings of this study.

Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances

PubMed Central

Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

2016-01-01

Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

Incorporation of oxygen into abscisic Acid and phaseic Acid from molecular oxygen.

PubMed

Creelman, R A; Zeevaart, J A

1984-05-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% (18)O(2) and 80% N(2) indicates that one atom of (18)O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase.Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing (18)O(2) indicates that one atom of (18)O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress.

Amino acid and fatty acid compositions of Rusip from fermented Anchovy fish (Stolephorussp)

NASA Astrophysics Data System (ADS)

Koesoemawardani, D.; Hidayati, S.; Subeki

2018-04-01

Rusip is a typical food of Bangka Belitung Indonesia made from fermented anchovy. This study aims to determine the properties of chemistry, microbiology, composition of amino acids and fatty acids from fermented fish spontaneously and non spontaneously. Spontaneous rusip treatment is done by anchovy fish (Stolephorussp) after cleaning and added salt 25% (w/w) and palm sugar 10% (w/w). While, non-spontaneous rusip is done by adding a culture mixture of Streptococcus, Leuconostoc, and Lactobacillus bacteria 2% (w/v). The materials are then incubated for 2 weeks. The data obtained were then performed t-test at the level of 5%. Spontaneous and non-spontaneous rusip fermentation process showed significant differences in total acid, reducing sugar, salt content, TVN, total lactic acid bacteria, total mold, and total microbial. The dominant amino acid content of spontaneous and non-spontaneous rusip are glutamic acid and aspartic acid, while the dominant fatty acids in spontaneous and non-spontaneous rusip are docosahexaenoic acid, palmitic acid, oleic acid, arachidonic acid, stearic acid, eicosapentaenoic acid, palmitoleic acid, and myristic acid.

Synthesis and Hydrolytic Degradation of Substituted Poly(DL-Lactic Acid)s

PubMed Central

Tsuji, Hideto; Eto, Takehiko; Sakamoto, Yuzuru

2011-01-01

Non-substituted racemic poly(DL-lactic acid) (PLA) and substituted racemic poly(DL-lactic acid)s or poly(DL-2-hydroxyalkanoic acid)s with different side-chain lengths, i.e., poly(DL-2-hydroxybutanoic acid) (PBA), poly(DL-2-hydroxyhexanoic acid) (PHA), and poly(DL-2-hydroxydecanoic acid) (PDA) were synthesized by acid-catalyzed polycondensation of DL-lactic acid (LA), DL-2-hydroxybutanoic acid (BA), DL-2-hydroxyhexanoic acid (HA), and DL-2-hydroxydecanoic acid (DA), respectively. The hydrolytic degradation behavior was investigated in phosphate-buffered solution at 80 and 37 °C by gravimetry and gel permeation chromatography. It was found that the reactivity of monomers during polycondensation as monitored by the degree of polymerization (DP) decreased in the following order: LA > DA > BA > HA. The hydrolytic degradation rate traced by DP and weight loss at 80 °C decreased in the following order: PLA > PDA > PHA > PBA and that monitored by DP at 37 °C decreased in the following order: PLA > PDA > PBA > PHA. LA and PLA had the highest reactivity during polymerization and hydrolytic degradation rate, respectively, and were followed by DA and PDA. BA, HA, PBA, and PHA had the lowest reactivity during polymerization and hydrolytic degradation rate. The findings of the present study strongly suggest that inter-chain interactions play a major role in the reactivity of non-substituted and substituted LA monomers and degradation rate of the non-substituted and substituted PLA, along with steric hindrance of the side chains as can be expected. PMID:28824149

Reduction of volatile acidity of acidic wines by immobilized Saccharomyces cerevisiae cells.

PubMed

Vilela, A; Schuller, D; Mendes-Faia, A; Côrte-Real, M

2013-06-01

Excessive volatile acidity in wines is a major problem and is still prevalent because available solutions are nevertheless unsatisfactory, namely, blending the filter-sterilized acidic wine with other wines of lower volatile acidity or using reverse osmosis. We have previously explored the use of an empirical biological deacidification procedure to lower the acetic acid content of wines. This winemaker's enological practice, which consists in refermentation associated with acetic acid consumption by yeasts, is performed by mixing the acidic wine with freshly crushed grapes, musts, or marc from a finished wine fermentation. We have shown that the commercial strain Saccharomyces cerevisiae S26 is able to decrease the volatile acidity of acidic wines with a volatile acidity higher than 1.44 g L(-1) acetic acid, with no detrimental impact on wine aroma. In this study, we aimed to optimize the immobilization of S26 cells in alginate beads for the bioreduction of volatile acidity of acidic wines. We found that S26 cells immobilized in double-layer alginate-chitosan beads could reduce the volatile acidity of an acidic wine (1.1 g L(-1) acetic acid, 12.5 % (v/v) ethanol, pH 3.12) by 28 and 62 % within 72 and 168 h, respectively, associated with a slight decrease in ethanol concentration (0.7 %). Similar volatile acidity removal efficiencies were obtained in medium with high glucose concentration (20 % w/v), indicating that this process may also be useful in the deacidification of grape musts. We, therefore, show that immobilized S. cerevisiae S26 cells in double-layer beads are an efficient alternative to improve the quality of wines with excessive volatile acidity.

21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and as...

21 CFR 172.862 - Oleic acid derived from tall oil fatty acids.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Oleic acid derived from tall oil fatty acids. 172... FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.862 Oleic acid derived from tall oil fatty acids. The food additive oleic acid derived from tall oil fatty acids may be safely used in food and as...

Short communication: Eicosatrienoic acid and docosatrienoic acid do not promote vaccenic acid accumulation in mixed ruminal cultures.

PubMed

AbuGhazaleh, A A; Holmes, L D; Jacobson, B N; Kalscheur, K F

2006-11-01

Previous research found that docosahexaenoic acid (C22:6n-3) was a component of fish oil that promotes trans-C18:1 accumulation in ruminal cultures when incubated with linoleic acid. The objective of this study was to determine if eicosatrienoic acid (C20:3n-3) and docosatrienoic acid (C22:3n-3), n-3 fatty acids in fish oil, promote accumulation of trans-C18:1, vaccenic acid (VA) in particular, using cultures of mixed ruminal microorganisms. Treatments consisted of control, control plus 5 mg of C20:3n-3 (ETA), control plus 5 mg of C22:3n-3 (DTA), control plus 15 mg of linoleic acid (LA), control plus 5 mg of C20:3n-3 and 15 mg of linoleic acid (ETALA), and control plus 5 mg of C22:3n-3 and 15 mg of linoleic acid (DTALA). Treatments were incubated in triplicate in 125-mL flasks, and 5 mL of culture contents was taken at 0 and 24 h for fatty acid analysis by gas-liquid chromatography. After 24 h of incubation, the concentrations of trans-C18:1 (0.87, 0.88, and 0.99 mg/culture), and VA (0.52, 0.56, and 0.62 mg/culture) were similar for the control, ETA, and DTA cultures, respectively. The concentrations of trans-C18:1 (5.51, 5.41, and 5.36 mg/culture), and VA (4.78, 4.62, and 4.59 mg/culture) were also similar between LA, ETALA, and DTALA cultures, respectively. These data suggest that C20:3n-3 and C22:3n-3 are not the active components in fish oil that promote VA accumulation when incubated with linoleic acid.

Fatty acid transfer between multilamellar liposomes and fatty acid-binding proteins.

PubMed

Brecher, P; Saouaf, R; Sugarman, J M; Eisenberg, D; LaRosa, K

1984-11-10

A simple experimental system was developed for studying the movement of long-chain fatty acids between multilamellar liposomes and soluble proteins capable of binding fatty acids. Oleic acid was incorporated into multilamellar liposomes containing cholesterol and egg yolk lecithin and incubated with albumin or hepatic fatty acid-binding protein. It was found that the fatty acid transferred from the liposomes to either protein rapidly and selectively under conditions where phospholipid and cholesterol transfer did not occur. More than 50% of the fatty acid contained within liposomes could become protein bound, suggesting that the fatty acid moved readily between and across phospholipid bilayers. Transfer was reduced at low pH, and this reduction appeared to result from decreased dissociation of the protonated fatty acid from the bilayer. Liposomes made with dimyristoyl or dipalmitoyl lecithin and containing 1 mol per cent palmitic acid were used to show the effect of temperature on fatty acid transfer. Transfer to either protein did not occur at temperatures where the liposomes were in a gel state but occurred rapidly at temperatures at or above the transition temperatures of the phospholipid used.

Proximate composition, amino acid and fatty acid composition of fish maws.

PubMed

Wen, Jing; Zeng, Ling; Xu, Youhou; Sun, Yulin; Chen, Ziming; Fan, Sigang

2016-01-01

Fish maws are commonly recommended and consumed in Asia over many centuries because it is believed to have some traditional medical properties. This study highlights and provides new information on the proximate composition, amino acid and fatty acid composition of fish maws of Cynoscion acoupa, Congresox talabonoides and Sciades proops. The results indicated that fish maws were excellent protein sources and low in fat content. The proteins in fish maws were rich in functional amino acids (FAAs) and the ratio of FAAs and total amino acids in fish maws ranged from 0.68 to 0.69. Among species, croaker C. acoupa contained the most polyunsaturated fatty acids, arachidonic acid, docosahexaenoic acid and eicosapntemacnioc acid, showing the lowest value of index of atherogenicity and index of thrombogenicity, showing the highest value of hypocholesterolemic/hypercholesterolemic ratio, which is the most desirable.

A Glutamic Acid-Producing Lactic Acid Bacteria Isolated from Malaysian Fermented Foods

PubMed Central

Zareian, Mohsen; Ebrahimpour, Afshin; Bakar, Fatimah Abu; Mohamed, Abdul Karim Sabo; Forghani, Bita; Ab-Kadir, Mohd Safuan B.; Saari, Nazamid

2012-01-01

l-glutamaic acid is the principal excitatory neurotransmitter in the brain and an important intermediate in metabolism. In the present study, lactic acid bacteria (218) were isolated from six different fermented foods as potent sources of glutamic acid producers. The presumptive bacteria were tested for their ability to synthesize glutamic acid. Out of the 35 strains showing this capability, strain MNZ was determined as the highest glutamic-acid producer. Identification tests including 16S rRNA gene sequencing and sugar assimilation ability identified the strain MNZ as Lactobacillus plantarum. The characteristics of this microorganism related to its glutamic acid-producing ability, growth rate, glucose consumption and pH profile were studied. Results revealed that glutamic acid was formed inside the cell and excreted into the extracellular medium. Glutamic acid production was found to be growth-associated and glucose significantly enhanced glutamic acid production (1.032 mmol/L) compared to other carbon sources. A concentration of 0.7% ammonium nitrate as a nitrogen source effectively enhanced glutamic acid production. To the best of our knowledge this is the first report of glutamic acid production by lactic acid bacteria. The results of this study can be further applied for developing functional foods enriched in glutamic acid and subsequently γ-amino butyric acid (GABA) as a bioactive compound. PMID:22754309

Acid-Base Homeostasis

PubMed Central

Nakhoul, Nazih; Hering-Smith, Kathleen S.

2015-01-01

Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. The importance of this regulation is evidenced by a variety of physiologic derangements that occur when plasma pH is either high or low. The kidneys have the predominant role in regulating the systemic bicarbonate concentration and hence, the metabolic component of acid-base balance. This function of the kidneys has two components: reabsorption of virtually all of the filtered HCO3− and production of new bicarbonate to replace that consumed by normal or pathologic acids. This production or generation of new HCO3− is done by net acid excretion. Under normal conditions, approximately one-third to one-half of net acid excretion by the kidneys is in the form of titratable acid. The other one-half to two-thirds is the excretion of ammonium. The capacity to excrete ammonium under conditions of acid loads is quantitatively much greater than the capacity to increase titratable acid. Multiple, often redundant pathways and processes exist to regulate these renal functions. Derangements in acid-base homeostasis, however, are common in clinical medicine and can often be related to the systems involved in acid-base transport in the kidneys. PMID:26597304

Photostabilization of ascorbic acid with citric acid, tartaric acid and boric acid in cream formulations.

PubMed

Ahmad, I; Ali Sheraz, M; Ahmed, S; Shad, Z; Vaid, F H M

2012-06-01

This study involves the evaluation of the effect of certain stabilizers, that is, citric acid (CT), tartaric acid (TA) and boric acid (BA) on the degradation of ascorbic acid (AH(2) ) in oil-in-water cream formulations exposed to the UV light and stored in the dark. The apparent first-order rate constants (0.34-0.95 × 10(-3) min(-1) in light, 0.38-1.24 × 10(-2) day(-1) in dark) for the degradation reactions in the presence of the stabilizers have been determined. These rate constants have been used to derive the second-order rate constants (0.26-1.45 × 10(-2) M(-1) min(-1) in light, 3.75-8.50 × 10(-3) M(-1) day(-1) in dark) for the interaction of AH(2) and the individual stabilizers. These stabilizers are effective in causing the inhibition of the rate of degradation of AH(2) both in the light and in the dark. The inhibitory effect of the stabilizers is in the order of CT > TA > BA. The rate of degradation of AH(2) in the presence of these stabilizers in the light is about 120 times higher than that in the dark. This could be explained on the basis of the deactivation of AH(2) -excited triplet state by CT and TA and by the inhibition of AH(2) degradation through complex formation with BA. AH(2) leads to the formation of dehydroascorbic acid (A) by chemical and photooxidation in cream formulations. © 2012 The Authors. ICS © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Docosahexaenoic acid affects arachidonic acid uptake in megakaryocytes

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

Schick, P.K.; Webster, P.

1987-05-01

Dietary omega 3 fatty acids are thought to prevent atherosclerosis, possibly by modifying platelet (PT) function and arachidonic acid (20:4) metabolism. The study was designed to determine whether omega 3 fatty acids primarily affect 20:4 metabolism in megakaryocytes (MK), bone marrow precursors of PT, rather than in circulating PT. MK and PT were isolated from guinea pigs and incubated with (/sup 14/C)-20:4 (0.13uM). Docosahexaenoic acid (22:6) is a major omega 3 fatty acid in marine oils. The incubation of MK with 22:6 (0.1, 1.0 uM) resulted in the decrease of incorporation of (/sup 14/C)-20:4 into total MK phospholipids, 16% andmore » 41% respectively. Alpha-linolenic acid (18:3), a major omega 3 fatty acid present in American diets, had no effect on 20:4 uptake in MK. 22:6 primarily affected the uptake of (/sup 14/C)-20:4 into phosphatidylethanolamine (PE) and phosphatidylserine (PS) in MK. In MK, 22:6 (0.1, 1.0 uM) caused a decrease of incorporation of (/sup 14/C)-20:4 into PE, 21% and 55% respectively; a decrease into PS, 16% and 48% respectively; but only a decrease of 4% and 18%, respectively, into phosphatidylcholine; and a decrease of 3% and 21% into phosphatidylinositol 22:6 (3.0 uM) had no effect on the uptake of AA into PT phospholipids. The study shows that 22:6 has a selective effect on AA uptake in MK and that the acylation or transacylation of PE and PS are primarily affected. 22:6 and other marine omega 3 fatty acids appear to primarily affect megakaryocytes which may result in the production of platelets with abnormal content and compartmentalization of AA.« less

Nicotinic Acid Metabolism, V. A Cobamide Coenzyme-Dependent Conversion of α-Methyleneglutaric Acid to Dimethylmaleic Acid

PubMed Central

Kung, H. F.; Cederbaum, S.; Tsai, L.; Stadtman, T. C.

1970-01-01

A new B12-coenzyme-dependent isomerization, catalyzed by extracts of a nicotinate-fermenting clostridium, results in the conversion of α-methyleneglutaric acid to dimethylmaleic acid. These two acids are intermediates in the multistep anaerobic process wherein nicotinate is converted, ultimately, to one mole each of propionate, acetate, carbon dioxide, and ammonia. Dimethylmaleic acid reacts in its anhydride form with 2,4-dinitrophenylhydrazine to form N-2′,4′-dinitrophenyl-anilino-3,4-dimethylmaleimide. The characteristic reddish color exhibited by the latter derivative in alkaline solution serves as a convenient quantitative assay for dimethylmaleic acid. Comparison of the 2,4-dinitrophenylhydrazine derivatives of the product of the enzymic reaction and of synthetic dimethylmaleic anhydride showed them to be identical in every respect. PMID:5266166

Hydroxycarboxylic acids and salts

DOEpatents

Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

2015-02-24

Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

Enantiomeric Excesses of Acid Labile Amino Acid Precursors of the Murchison Meteorite

NASA Astrophysics Data System (ADS)

Pizzarello, Sandra

1998-10-01

Amino acids present in carbonaceous chondrite are extracted in water in part as free compounds and in approximately equal part as acid labile precursors. On the assumption that they would be free of contamination, the precursors of two Murchison amino acids that have terrestrial occurrence, alanine and glutamic acid, have been targeted for analysis of their enantiomeric ratios. Pyroglutamic acid, the precursor of glutamic acid, was found with an L-enantiomeric excess comparable to that of the free acid, while alanine's precursor, N-acetyl alanine, appears approximately racemic. Also alpha-imino propioacetic acid, a proposed end product of alanine synthesis in the meteorite, was analyzed and found racemic.

Enantiomeric Excesses of Acid Labile Amino Acid Precursors of the Murchison Meteorite

NASA Technical Reports Server (NTRS)

Pizzarello, Sandra

1998-01-01

Amino acids present in carbonaceous chondrite are extracted in water in part as free compounds and in approximately equal part as acid labile precursors. On the assumption that they would be free of contamination, the precursors of two Murchison amino acids that have terrestrial occurrence, alanine and glutamic acid, have been targeted for analysis of their enantiomeric ratios. Pyroglutamic acid, the precursor of glutamic acid, was found with an L-enantiomeric excess comparable to that of the free acid, while alanine's precursor, N-acetyl alanine, appears approximately racemic. Also alpha-imino propioacetic acid, a proposed end product of alanine synthesis in the meteorite, was analyzed and found racemic.

Molecular composition and size distribution of sugars, sugar-alcohols and carboxylic acids in airborne particles during a severe urban haze event caused by wheat straw burning

NASA Astrophysics Data System (ADS)

Wang, Gehui; Chen, Chunlei; Li, Jianjun; Zhou, Bianhong; Xie, Mingjie; Hu, Shuyuan; Kawamura, Kimitaka; Chen, Yan

2011-05-01

Molecular compositions and size distributions of water-soluble organic compounds (WSOC, i.e., sugars, sugar-alcohols and carboxylic acids) in particles from urban air of Nanjing, China during a severe haze event caused by field burning of wheat straw were characterized and compared with those in the summer and autumn non-haze periods. During the haze event levoglucosan (4030 ng m -3) was the most abundant compound among the measured WSOC, followed by succinic acid, malic acid, glycerol, arabitol and glucose, being different from those in the non-haze samples, in which sucrose or azelaic acid showed a second highest concentration, although levoglucosan was the highest. The measured WSOC in the haze event were 2-20 times more than those in the non-hazy days. Size distribution results showed that there was no significant change in the compound peaks in coarse mode (>2.1 μm) with respect to the haze and non-haze samples, but a large difference in the fine fraction (<2.1 μm) was found with a sharp increase during the hazy days mostly due to the increased emissions of wheat straw burning. Molecular compositions of organic compounds in the fresh smoke particles from wheat straw burning demonstrate that sharply increased concentrations of glycerol and succinic and malic acids in the fine particles during the haze event were mainly derived from the field burning of wheat straw, although the sources of glucose and related sugar-alcohols whose concentrations significantly increased in the fine haze samples are unclear. Compared to that in the fresh smoke particles of wheat straw burning an increase in relative abundance of succinic acid to levoglucosan during the haze event suggests a significant production of secondary organic aerosols during transport of the smoke plumes.

Organic acid-tolerant microorganisms and uses thereof for producing organic acids

DOEpatents

Pfleger, Brian Frederick; Begemann, Matthew Brett

2014-05-06

Organic acid-tolerant microorganisms and methods of using same. The organic acid-tolerant microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid (3HP), acrylic acid, and propionic acid. Further modifications to the microorganisms such as increasing expression of malonyl-CoA reductase and/or acetyl-CoA carboxylase provide or increase the ability of the microorganisms to produce 3HP. Methods of generating an organic acid with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers include replacing acsA or homologs thereof in cells with genes of interest and selecting for the cells comprising the genes of interest with amounts of organic acids effective to inhibit growth of cells harboring acsA or the homologs.

Extraterrestrial material analysis: loss of amino acids during liquid-phase acid hydrolysis

NASA Astrophysics Data System (ADS)

Buch, Arnaud; Brault, Amaury; Szopa, Cyril; Freissinet, Caroline

2015-04-01

Searching for building blocks of life in extraterrestrial material is a way to learn more about how life could have appeared on Earth. With this aim, liquid-phase acid hydrolysis has been used, since at least 1970 , in order to extract amino acids and other organic molecules from extraterrestrial materials (e.g. meteorites, lunar fines) or Earth analogues (e.g. Atacama desert soil). This procedure involves drastic conditions such as heating samples in 6N HCl for 24 h, either under inert atmosphere/vacuum, or air. Analysis of the hydrolyzed part of the sample should give its total (free plus bound) amino acid content. The present work deals with the influence of the 6N HCl hydrolysis on amino acid degradation. Our experiments have been performed on a standard solution of 17 amino acids. After liquid-phase acid hydrolysis (6N HCl) under argon atmosphere (24 h at 100°C), the liquid phase was evaporated and the dry residue was derivatized with N-Methyl-N-(t-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF), followed by gas chromatography-mass spectrometry analysis. After comparison with derivatized amino acids from the standard solution, a significant reduction of the chromatographic peak areas was observed for most of the amino acids after liquid-phase acid hydrolysis. Furthermore, the same loss pattern was observed when the amino acids were exposed to cold 6N HCl for a short amount of time. The least affected amino acid, i.e. glycine, was found to be 73,93% percent less abundant compared to the non-hydrolyzed standard, while the most affected, i.e. histidine, was not found in the chromatograms after hydrolysis. Our experiments thereby indicate that liquid-phase acid hydrolysis, even under inert atmosphere, leads to a partial or total loss of all of the 17 amino acids present in the standard solution, and that a quick cold contact with 6N HCl is sufficient to lead to a loss of amino acids. Therefore, in the literature, the reported increase

Docosahexaenoic acid synthesis from alpha-linolenic acid is inhibited by diets high in polyunsaturated fatty acids.

PubMed

Gibson, R A; Neumann, M A; Lien, E L; Boyd, K A; Tu, W C

2013-01-01

The conversion of the plant-derived omega-3 (n-3) α-linolenic acid (ALA, 18:3n-3) to the long-chain eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) can be increased by ALA sufficient diets compared to ALA deficient diets. Diets containing ALA above an optimal level result in no further increase in DHA levels in animals and humans. The present study evaluates means of maximizing plasma DHA accumulation by systematically varying both linoleic acid (LA, 18:2n-6) and ALA dietary level. Weanling rats were fed one of 54 diets for three weeks. The diets varied in the percentage of energy (en%) of LA (0.07-17.1 en%) and ALA (0.02-12.1 en%) by manipulating both the fat content and the balance of vegetable oils. The peak of plasma phospholipid DHA (>8% total fatty acids) was attained as a result of feeding a narrow dietary range of 1-3 en% ALA and 1-2 en% LA but was suppressed to basal levels (∼2% total fatty acids) at dietary intakes of total polyunsaturated fatty acids (PUFA) above 3 en%. We conclude it is possible to enhance the DHA status of rats fed diets containing ALA as the only source of n-3 fatty acids but only when the level of dietary PUFA is low (<3 en%). Copyright © 2012 Elsevier Ltd. All rights reserved.

40 CFR 721.2086 - Coco acid triamine condensate, polycarboxylic acid salts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Coco acid triamine condensate, polycarboxylic acid salts. 721.2086 Section 721.2086 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.2086 Coco acid triamine condensate, polycarboxylic acid salts. (a...

Nitrous Acid as an Oxidant in Acidic Media

DTIC Science & Technology

1979-09-25

nitroso oxidations were run in sulfuric acid. The Hammett acidity function is used as the abscissa because it conveniently represents the acidity region...oxidation. 13 Consistent with the general mechanism, equations (1)-(3), and in contrast to nitration, phenol nitrosation displays a primary kinetic...oxidized 1(III) + Alc - 104O + C-O (4) with the only route now removing HNO being NO+ + H - H + + 2N0 (5) Apparently while alcohol remains, equation (5

A comparison of chromic acid and sulfuric acid anodizing

NASA Technical Reports Server (NTRS)

Danford, M. D.

1992-01-01

Because of federal and state mandates restricting the use of hexavalent chromium, it was deemed worthwhile to compare the corrosion protection afforded 2219-T87 aluminum alloy by both Type I chromic acid and Type II sulfuric acid anodizing per MIL-A-8625. Corrosion measurements were made on large, flat 2219-T87 aluminum alloy sheet material with an area of 1 cm(exp 2) exposed to a corrosive medium of 3.5-percent sodium chloride at pH 5.5. Both ac electrochemical impedance spectroscopy and the dc polarization resistance techniques were employed. The results clearly indicate that the corrosion protection obtained by Type II sulfuric acid anodizing is superior, and no problems should result by substituting Type II sulfuric acid anodizing for Type I chromic acid anodizing.

Acidic Ionic Liquids.

PubMed

Amarasekara, Ananda S

2016-05-25

Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

Electronic structures and spectra of two antioxidants: uric acid and ascorbic acid

NASA Astrophysics Data System (ADS)

Shukla, M. K.; Mishra, P. C.

1996-04-01

Electronic absorption and fluorescence spectra of aqueous solutions of two well known antioxidants, uric acid and ascorbic acid (vitamin C), have been studied at different pH. The observed spectra have been interpreted in terms of neutral and anionic forms of the molecules with the help of molecular orbital calculations. The N 3 site of uric acid has been shown to be the most acidic. Fluorescence of uric acid seems to originate from an anion of the molecule in a wide pH range. Around pH 3, both the neutral and anionic forms of ascorbic acid appear to be present in aqueous solutions. In aqueous media, ascorbic acid appears to get converted easily to its dehydro form and this conversion does not seem to be reversible. An anion of dehydroascorbic acid seems to be formed on heating dehydroascorbic acid in aqueous solutions.

Growth of nitric acid hydrates on thin sulfuric acid films

NASA Technical Reports Server (NTRS)

Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

1994-01-01

Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

Chronic Arachidonic Acid Administration Decreases Docosahexaenoic Acid- and Eicosapentaenoic Acid-Derived Metabolites in Kidneys of Aged Rats.

PubMed

Katakura, Masanori; Hashimoto, Michio; Inoue, Takayuki; Mamun, Abdullah Al; Tanabe, Yoko; Arita, Makoto; Shido, Osamu

2015-01-01

Arachidonic acid (ARA) metabolites produced by cyclo-oxygenase and lipoxygenase are important mediators maintaining physiological renal function. However, the effects of exogenous ARA on kidney function in vivo remain unknown. This study examined the effects of long-term oral ARA administration on normal renal function as well as inflammation and oxidative stress in aged rats. In addition, we measured levels of renal eicosanoids and docosanoids using liquid chromatography-tandem mass spectrometry. Control or ARA oil (240 mg/kg body weight/day) was orally administered to 21-month-old Wistar rats for 13 weeks. Levels of plasma creatinine, blood urea nitrogen, inflammatory and anti-inflammatory cytokines, reactive oxygen species, and lipid peroxidation were not significantly different between the two groups. The ARA concentration in the plasma, kidney, and liver increased in the ARA-administered group. In addition, levels of free-form ARA, prostaglandin E2, and 12- and 15-hydroxyeicosatetraenoic acid increased in the ARA-administered group, whereas renal concentration of docosahexaenoic acid and eicosapentaenoic acid decreased in the ARA-administered group. Levels of docosahexaenoic acid-derived protectin D1, eicosapentaenoic acid-derived 5-, and 18-hydroxyeicosapentaenoic acids, and resolvin E2 and E3 decreased in the ARA-administered group. Our results indicate that long-term ARA administration led to no serious adverse reactions under normal conditions and to a decrease in anti-inflammatory docosahexaenoic acid- and eicosapentaenoic acid-derived metabolites in the kidneys of aged rats. These results indicate that there is a possibility of ARA administration having a reducing anti-inflammatory effect on the kidney.

Chronic Arachidonic Acid Administration Decreases Docosahexaenoic Acid- and Eicosapentaenoic Acid-Derived Metabolites in Kidneys of Aged Rats

PubMed Central

Katakura, Masanori; Hashimoto, Michio; Inoue, Takayuki; Mamun, Abdullah Al; Tanabe, Yoko; Arita, Makoto; Shido, Osamu

2015-01-01

Arachidonic acid (ARA) metabolites produced by cyclo-oxygenase and lipoxygenase are important mediators maintaining physiological renal function. However, the effects of exogenous ARA on kidney function in vivo remain unknown. This study examined the effects of long-term oral ARA administration on normal renal function as well as inflammation and oxidative stress in aged rats. In addition, we measured levels of renal eicosanoids and docosanoids using liquid chromatography–tandem mass spectrometry. Control or ARA oil (240 mg/kg body weight/day) was orally administered to 21-month-old Wistar rats for 13 weeks. Levels of plasma creatinine, blood urea nitrogen, inflammatory and anti-inflammatory cytokines, reactive oxygen species, and lipid peroxidation were not significantly different between the two groups. The ARA concentration in the plasma, kidney, and liver increased in the ARA-administered group. In addition, levels of free-form ARA, prostaglandin E2, and 12- and 15-hydroxyeicosatetraenoic acid increased in the ARA-administered group, whereas renal concentration of docosahexaenoic acid and eicosapentaenoic acid decreased in the ARA-administered group. Levels of docosahexaenoic acid-derived protectin D1, eicosapentaenoic acid-derived 5-, and 18-hydroxyeicosapentaenoic acids, and resolvin E2 and E3 decreased in the ARA-administered group. Our results indicate that long-term ARA administration led to no serious adverse reactions under normal conditions and to a decrease in anti-inflammatory docosahexaenoic acid- and eicosapentaenoic acid-derived metabolites in the kidneys of aged rats. These results indicate that there is a possibility of ARA administration having a reducing anti-inflammatory effect on the kidney. PMID:26485038

"JCE" Classroom Activity #109: My Acid Can Beat Up Your Acid!

ERIC Educational Resources Information Center

Putti, Alice

2011-01-01

In this guided-inquiry activity, students investigate the ionization of strong and weak acids. Bead models are used to study acid ionization on a particulate level. Students analyze seven strong and weak acid models and make generalizations about the relationship between acid strength and dissociation. (Contains 1 table and 2 figures.)

Metabolic pathways regulated by abscisic acid, salicylic acid and γ-aminobutyric acid in association with improved drought tolerance in creeping bentgrass (Agrostis stolonifera).

PubMed

Li, Zhou; Yu, Jingjin; Peng, Yan; Huang, Bingru

2017-01-01

Abscisic acid (ABA), salicylic acid (SA) and γ-aminobutyric acid (GABA) are known to play roles in regulating plant stress responses. This study was conducted to determine metabolites and associated pathways regulated by ABA, SA and GABA that could contribute to drought tolerance in creeping bentgrass (Agrostis stolonifera). Plants were foliar sprayed with ABA (5 μM), GABA (0.5 mM) and SA (10 μM) or water (untreated control) prior to 25 days drought stress in controlled growth chambers. Application of ABA, GABA or SA had similar positive effects on alleviating drought damages, as manifested by the maintenance of lower electrolyte leakage and greater relative water content in leaves of treated plants relative to the untreated control. Metabolic profiling showed that ABA, GABA and SA induced differential metabolic changes under drought stress. ABA mainly promoted the accumulation of organic acids associated with tricarboxylic acid cycle (aconitic acid, succinic acid, lactic acid and malic acid). SA strongly stimulated the accumulation of amino acids (proline, serine, threonine and alanine) and carbohydrates (glucose, mannose, fructose and cellobiose). GABA enhanced the accumulation of amino acids (GABA, glycine, valine, proline, 5-oxoproline, serine, threonine, aspartic acid and glutamic acid) and organic acids (malic acid, lactic acid, gluconic acid, malonic acid and ribonic acid). The enhanced drought tolerance could be mainly due to the enhanced respiration metabolism by ABA, amino acids and carbohydrates involved in osmotic adjustment (OA) and energy metabolism by SA, and amino acid metabolism related to OA and stress-defense secondary metabolism by GABA. © 2016 Scandinavian Plant Physiology Society.

Complexity in Acid-Base Titrations: Multimer Formation Between Phosphoric Acids and Imines.

PubMed

Malm, Christian; Kim, Heejae; Wagner, Manfred; Hunger, Johannes

2017-08-10

Solutions of Brønsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Brønsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid-base aggregates challenging. Here, we track such acid-base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by using a combination of dielectric relaxation and NMR spectroscopy. In contrast to what one would expect for an acid-base titration, we find strong deviations from quantitative proton transfer from the acid to the base. Even for an excess of the base, multimers consisting of one base and at least two acid molecules are formed, in addition to the occurrence of proton transfer from the acid to the base and simultaneous formation of ion pairs. For equimolar mixtures such multimers constitute about one third of all intermolecular aggregates. Quantitative analysis of our results shows that the acid-base association constant is only around six times larger than that for the acid binding to an acid-base dimer, that is, to an already protonated base. Our findings have implications for the interpretation of previous studies of reactive intermediates in organocatalysis and provide a rationale for previously observed nonlinear effects in phosphoric acid catalysis. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Nocturnal weakly acidic reflux promotes aspiration of bile acids in lung transplant recipients.

PubMed

Blondeau, Kathleen; Mertens, Veerle; Vanaudenaerde, Bart A; Verleden, Geert M; Van Raemdonck, Dirk E; Sifrim, Daniel; Dupont, Lieven J

2009-02-01

Gastroesophageal reflux (GER) and aspiration of bile acids have been implicated as non-alloimmune risk factors for the development of bronchiolitis obliterans syndrome (BOS) after lung transplantation. The aim of our study was to investigate the association between GER and gastric aspiration of bile acids and to establish which reflux characteristics may promote aspiration of bile acids into the lungs and may feature as a potential diagnostic tool in identifying lung transplantation (LTx) patients at risk for aspiration. Twenty-four stable LTx recipients were studied 1 year after transplantation. All patients underwent 24-hour ambulatory impedance-pH recording for the detection of acid (pH <4) and weakly acidic (pH 4 to 7) reflux. On the same day, bronchoalveolar lavage fluid (BALF) was collected and then analyzed for the presence of bile acids (Bioquant enzymatic assay). Increased GER was detected in 13 patients, of whom 9 had increased acid reflux and 4 had exclusively increased weakly acidic reflux. Sixteen patients had detectable bile acids in the BALF (0.6 [0.4 to 1.5] micromol/liter). The 24-hour esophageal volume exposure was significantly increased in patients with bile acids compared to patients without bile acids in the BALF. Acid exposure and the number of reflux events (total, acid and weakly acidic) were unrelated to the presence of bile acids in the BALF. However, both nocturnal volume exposure and the number of nocturnal weakly acidic reflux events were significantly higher in patients with bile acids in the BALF. Weakly acidic reflux events, especially during the night, are associated with the aspiration of bile acids in LTx recipients and may therefore feature as a potential risk factor for the development of BOS.

[Molecular docking of chlorogenic acid, 3,4-di-O-caffeoylquinic acid and 3,5-di-O-caffeoylquinic acid with human serum albumin].

PubMed

Zhou, Jing; Ma, Hong-yue; Fan, Xin-sheng; Xiao, Wei; Wang, Tuan-jie

2012-10-01

To investigate the mechanism of binding of human serum albumin (HSA) with potential sensitinogen, including chlorogenic acid and two isochlorogenic acids (3,4-di-O-caffeoylquinic acid and 3,5-di-O-caffeoylquinic acid). By using the docking algorithm of computer-aided molecular design and the Molegro Virtual Docker, the crystal structures of HSA with warfarin and diazepam (Protein Data Bank ID: 2BXD and 2BXF) were selected as molecular docking receptors of HSA sites I and II. According to docking scores, key residues and H-bond, the molecular docking mode was selected and confirmed. The molecular docking of chlorogenic acid and two isochlorogenic acids on sites I and II was compared based on the above design. The results from molecular docking indicated that chlorogenic acid, 3,4-di-O-caffeoylquinic acid and 3,5-di-O-caffeoylquinic acid could bind to HSA site I by high affinity scores of -112.3, -155.3 and -153.1, respectively. They could bind to site II on HSA by high affinity scores of -101.7, -138.5 and -133.4, respectively. In site I, two isochlorogenic acids interacted with the key apolar side-chains of Leu238 and Ala291 by higher affinity scores than chlorogenic acid. Furthermore, the H-bonds of isochlorogenic acids with polar residues inside the pocket and at the entrance of the pocket were different from chlorogenic acid. Moreover, the second coffee acyl of isochlorogenic acid occupied the right-hand apolar compartment in the pocket of HSA site I. In site I, the second coffee acyl of isochlorogenic acid formed the H-bonds with polar side-chains, which contributed isochlorogenic acid to binding with site II of HSA. The isochlorogenic acids with two coffee acyls have higher binding abilities with HSA than chlorogenic acid with one coffee acyl, suggesting that isochlorogenic acids binding with HSA may be sensitinogen.

Dicarboxylic acids, ketocarboxylic acids, α-dicarbonyls, fatty acids, and benzoic acid in urban aerosols collected during the 2006 Campaign of Air Quality Research in Beijing (CAREBeijing-2006)

NASA Astrophysics Data System (ADS)

Ho, K. F.; Lee, S. C.; Ho, Steven Sai Hang; Kawamura, Kimitaka; Tachibana, Eri; Cheng, Y.; Zhu, Tong

2010-10-01

Ground-based studies of PM2.5 were conducted for determination of 30 water-soluble organic species, including dicarboxylic acids, ketocarboxylic acids and dicarbonyls, nine fatty acids, and benzoic acid, during the Campaign of Air Quality Research in Beijing 2006 (CAREBeijing-2006; 21 August to 4 September 2006) at urban (Peking University, PKU) and suburban (Yufa) sites of Beijing. Molecular distributions of dicarboxylic acids demonstrated that oxalic acid (C2) was the most abundant species, followed by phthalic acid (Ph) and succinic acid (C4) at both sites. The sum of three dicarboxylic acids accounted for 71% and 74% of total quantified water-soluble organics (327-1552 and 329-1124 ng m-3) in PKU and Yufa, respectively. Positive correlation was found between total quantified water-soluble species and water-soluble organic compounds (WSOC). On a carbon basis, total quantified dicarboxylic acids and ketocarboxylic acids and dicarbonyls account for up to 14.2% and 30.4% of the WSOC in PKU and Yufa, respectively, suggesting that they are the major WSOC fractions in Beijing. The distributions of fatty acids are characterized by a strong even carbon number predominance with maximum at hexadecanoic acid (C16:0). The ratio of octadecanoic acid (C18:0) to hexadecanoic acid (C16:0) (0.39-0.85, with an average of 0.36) suggests that in addition to vehicular emissions, an input from cooking emissions is important, as is biogenic emission. Benzoic acid that has been proposed as a primary pollutant from vehicular exhaust and a secondary product from photochemical reactions was found to be abundant: 72.2 ± 58.1 ng m-3 in PKU and 78.0 ± 47.3 ng m-3 in Yufa. According to the 72 hour back trajectory analysis, when the air mass passed over the southern or southeastern part of Beijing (24-25 August and 1-2 September), the highest concentrations of organic compounds were observed. On the contrary, when the clean air masses came straight from the north during 3-4 September, the

Contribution of acidic components to the total acid number (TAN) of bio-oil

DOE PAGES

Park, Lydia K-E.; Liu, Jiaojun; Yiacoumi, Sotira; ...

2017-03-28

Bio-oil or pyrolysis oil — a product of thermochemical decomposition of biomass under oxygen-limited conditions — holds great potential to be a substitute for nonrenewable fossil fuels. But, its high acidity, which is primarily due to the degradation of hemicelluloses, limits its applications. For the evaluation of bio-oil production and treatment, it is essential to accurately measure the acidity of bio-oil. The total acid number (TAN), which is defined as the amount of potassium hydroxide needed to titrate one gram of a sample and has been established as an ASTM method to measure the acidity of petroleum products, has beenmore » employed to investigate the acidity of bio-oil. The TAN values of different concentrations of bio-oil components such as standard solutions of acetic acid, propionic acid, vanillic acid, hydroxybenzoic acid, syringic acid, hydroxymethylfurfural, and phenol were analyzed according to the ASTM D664 standard method. Our method showed the same linear relationship between the TAN values and the molar concentrations of acetic, propionic, and hydroxybenzoic acids. A different linear relationship was found for vanillic acid, due to the presence of multiple functional groups that can contribute to the TAN value. Furthermore, the influence of the titration solvent on the TAN values has been determined by comparing the TAN values and titration curves obtained from the standard method with results from the TAN analysis in aqueous environment and with equilibrium modeling results. Aqueous bio-oil samples with a known amount of acetic acid added were also analyzed. The additional acetic acid in bio-oil samples caused a proportional increase in the TAN values. These results of this research indicate that the TAN value of a sample with acids acting as monoprotic acids in the titration solvent can be converted to the molar concentration of total acids. For a sample containing acids that act as diprotic and polyprotic acids, however, its TAN value

Contribution of acidic components to the total acid number (TAN) of bio-oil

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

Park, Lydia K-E.; Liu, Jiaojun; Yiacoumi, Sotira

Bio-oil or pyrolysis oil — a product of thermochemical decomposition of biomass under oxygen-limited conditions — holds great potential to be a substitute for nonrenewable fossil fuels. But, its high acidity, which is primarily due to the degradation of hemicelluloses, limits its applications. For the evaluation of bio-oil production and treatment, it is essential to accurately measure the acidity of bio-oil. The total acid number (TAN), which is defined as the amount of potassium hydroxide needed to titrate one gram of a sample and has been established as an ASTM method to measure the acidity of petroleum products, has beenmore » employed to investigate the acidity of bio-oil. The TAN values of different concentrations of bio-oil components such as standard solutions of acetic acid, propionic acid, vanillic acid, hydroxybenzoic acid, syringic acid, hydroxymethylfurfural, and phenol were analyzed according to the ASTM D664 standard method. Our method showed the same linear relationship between the TAN values and the molar concentrations of acetic, propionic, and hydroxybenzoic acids. A different linear relationship was found for vanillic acid, due to the presence of multiple functional groups that can contribute to the TAN value. Furthermore, the influence of the titration solvent on the TAN values has been determined by comparing the TAN values and titration curves obtained from the standard method with results from the TAN analysis in aqueous environment and with equilibrium modeling results. Aqueous bio-oil samples with a known amount of acetic acid added were also analyzed. The additional acetic acid in bio-oil samples caused a proportional increase in the TAN values. These results of this research indicate that the TAN value of a sample with acids acting as monoprotic acids in the titration solvent can be converted to the molar concentration of total acids. For a sample containing acids that act as diprotic and polyprotic acids, however, its TAN value

Amino acid analysis

NASA Technical Reports Server (NTRS)

Winitz, M.; Graff, J. (Inventor)

1974-01-01

The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

Incorporation of Oxygen into Abscisic Acid and Phaseic Acid from Molecular Oxygen 1

PubMed Central

Creelman, Robert A.; Zeevaart, Jan A. D.

1984-01-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18O2 and 80% N2 indicates that one atom of 18O is incorporated in the 6′-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18O2 indicates that one atom of 18O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1′-, 4′-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1′- and 4′-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. PMID:16663564

Synthesis and biological activity of amino acid conjugates of abscisic acid.

PubMed

Todoroki, Yasushi; Narita, Kenta; Muramatsu, Taku; Shimomura, Hajime; Ohnishi, Toshiyuki; Mizutani, Masaharu; Ueno, Kotomi; Hirai, Nobuhiro

2011-03-01

We prepared 19 amino acid conjugates of the plant hormone abscisic acid (ABA) and investigated their biological activity, enzymatic hydrolysis by a recombinant Arabidopsis amidohydrolases GST-ILR1 and GST-IAR3, and metabolic fate in rice seedlings. Different sets of ABA-amino acids induced ABA-like responses in different plants. Some ABA-amino acids, including some that were active in bioassays, were hydrolyzed by recombinant Arabidopsis GST-IAR3, although GST-ILR1 did not show hydrolysis activity for any of the ABA-amino acids. ABA-L-Ala, which was active in all the bioassays, an Arabidopsis seed germination, spinach seed germination, and rice seedling elongation assays, except in a lettuce seed germination assay and was hydrolyzed by GST-IAR3, was hydrolyzed to free ABA in rice seedlings. These findings suggest that some plant amidohydrolases hydrolyze some ABA-amino acid conjugates. Because our study indicates the possibility that different plants have hydrolyzing activity toward different ABA-amino acids, an ABA-amino acid may function as a species-selective pro-hormone of ABA. Copyright © 2011 Elsevier Ltd. All rights reserved.

Hydroxamic acids as weak base indicators: protonation in strong acid media.

PubMed

García, B; Ibeas, S; Hoyuelos, F J; Leal, J M; Secco, F; Venturini, M

2001-11-30

The protonation equilibria of N-phenylbenzohydroxamic, benzohydroxamic, salicylhydroxamic, and N-p-tolylcinnamohydroxamic acids have been studied at 25 degrees C in concentrated sulfuric, hydrochloric, and perchloric acid media; the UV-vis spectral measurements were analyzed using the Hammett equation and the Bunnett-Olsen and excess acidity methods. The medium effects observed in the UV spectral curves were corrected with the Cox-Yates and vector analysis methods. The H(A) acidity function based on benzamides provided the best results. The range of variation of the solvation coefficient m is similar to that of amides, this indicating similar solvation requirements for amides and hydroxamic acids. For the same substrate, the observed variations of pK(BH)(+) with the mineral acid used was justified by formation of solvent-separated ion pairs; for the same mineral acid, the observed changes in pK(BH)(+) can be explained by the solvation of BH(+). The change of the pK(BH)(+) values was in reasonably good agreement with the sequence of the catalytic efficiency of the mineral acids used, HCl > H(2)SO(4) > HClO(4).

Differential regulation of placental amino acid transport by saturated and unsaturated fatty acids.

PubMed

Lager, Susanne; Jansson, Thomas; Powell, Theresa L

2014-10-15

Fatty acids are critical for normal fetal development but may also influence placental function. We have previously reported that oleic acid (OA) stimulates amino acid transport in primary human trophoblasts (PHTs). In other tissues, saturated and unsaturated fatty acids have distinct effects on cellular signaling, for instance, palmitic acid (PA) but not OA reduces IκBα expression. We hypothesized that saturated and unsaturated fatty acids differentially affect trophoblast amino acid transport and cellular signaling. To test this hypothesis, PHTs were cultured in docosahexaenoic acid (DHA; 50 μM), OA (100 μM), or PA (100 μM). DHA and OA were also combined to test whether DHA could counteract the OA stimulatory effect on amino acid transport. The effects of fatty acids were compared against a vehicle control. Amino acid transport was measured by isotope-labeled tracers. Activation of inflammatory-related signaling pathways and the mechanistic target of rapamycin (mTOR) pathway were determined by Western blot analysis. Exposure of PHTs to DHA for 24 h reduced amino acid transport and phosphorylation of p38 MAPK, STAT3, mTOR, eukaryotic initiation factor 4E-binding protein 1, and ribosomal protein (rp)S6. In contrast, OA increased amino acid transport and phosphorylation of ERK, mTOR, S6 kinase 1, and rpS6. The combination of DHA with OA increased amino acid transport and rpS6 phosphorylation. PA did not affect amino acid transport but reduced IκBα expression. In conclusion, these fatty acids differentially regulated placental amino acid transport and cellular signaling. Taken together, these findings suggest that dietary fatty acids could alter the intrauterine environment by modifying placental function, thereby having long-lasting effects on the developing fetus. Copyright © 2014 the American Physiological Society.

Variation of unsaturated fatty acids in soybean sprout of high oleic acid accessions.

PubMed

Dhakal, Krishna Hari; Jung, Ki-Hwal; Chae, Jong-Hyun; Shannon, J Grover; Lee, Jeong-Dong

2014-12-01

Oleic acid and oleic acid rich foods may have beneficial health effects in humans. Soybeans with high oleic acid (around 80% in seed oil) have been developed. Soybean sprouts are an important vegetable in Korea, Japan and China. The objective of this study was to investigate the variation of unsaturated fatty acids, oleic, linoleic and α-linolenic acids, in sprouts from soybeans with normal and high oleic acid concentration. Twelve soybean accessions with six high oleic acid lines, three parents of high oleic acid lines, and three checks with normal and high oleic acid concentration were used in this study. The unsaturated fatty acid concentration in sprouts from each genotype was similar to the concentration in the ungerminated seed. The oleic acid concentration in the sprouts of high oleic acid lines (up to 80%) was still high (>70%) compared to the ungerminated seed. Thus, high oleic soybean varieties developed for sprout production could add valuable health benefits to sprouts and the individuals who consume this vegetable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Secondary formation of water-soluble organic acids and α-dicarbonyls and their contributions to total carbon and water-soluble organic carbon: Photochemical aging of organic aerosols in the Arctic spring

NASA Astrophysics Data System (ADS)

Kawamura, Kimitaka; Kasukabe, Hideki; Barrie, Leonard A.

2010-11-01

Water-soluble dicarboxylic acids (C2-C12), ketocarboxylic acids (C2-C6, C9), and α-dicarbonyls (glyoxal and methylglyoxal) were determined in the Arctic aerosols collected in winter to early summer, as well as aerosol total carbon (TC) and water-soluble organic carbon (WSOC). Concentrations of TC and WSOC gradually decreased from late February to early June with a peak in spring, indicating a photochemical formation of water-soluble organic aerosols at a polar sunrise. We found that total (C2-C11) diacids (7-84 ng m-3) increased at polar sunrise by a factor of 4 and then decreased toward summer. Their contributions to TC (average 4.0%) peaked in early April and mid-May. The contribution of total diacids to WSOC was on average 7.1%. It gradually increased from February (5%) to a maximum in April (12.7%) with a second peak in mid-May (10.4%). Although oxalic acid (C2) is the dominant diacid until April, its predominance was replaced by succinic acid (C4) after polar sunrise. This may indicate that photochemical production of C2 was overwhelmed by its degradation when solar radiation was intensified and the atmospheric transport of its precursors from midlatitudes to the Arctic was ended in May. Interestingly, the contributions of azelaic (C9) and ω-oxobutanoic acids to WSOC increased in early summer possibly due to an enhanced emission of biogenic unsaturated fatty acids from the ocean followed by photochemical oxidation in the atmosphere. An enhanced contribution of diacids to TC and WSOC at polar sunrise may significantly alter the hygroscopic properties of organic aerosols in the Arctic.

Pentadecanoic and Heptadecanoic Acids: Multifaceted Odd-Chain Fatty Acids12

PubMed Central

Pfeuffer, Maria; Jaudszus, Anke

2016-01-01

The odd-chain fatty acids (OCFAs) pentadecanoic acid (15:0) and heptadecanoic acid (17:0), which account for only a small proportion of total saturated fatty acids in milk fat and ruminant meat, are accepted biomarkers of dairy fat intake. However, they can also be synthesized endogenously, for example, from gut-derived propionic acid (3:0). A number of studies have shown an inverse association between OCFA concentrations in human plasma phospholipids or RBCs and risk of type 2 diabetes and cardiovascular disease. We propose a possible involvement in metabolic regulation from the assumption that there is a link between 15:0 and 17:0 and the metabolism of other short-chain, medium-chain, and longer-chain OCFAs. The OCFAs 15:0 and 17:0 can be elongated to very-long-chain FAs (VLCFAs) such as tricosanoic acid (23:0) and pentacosanoic acid (25:0) in glycosphingolipids, particularly found in brain tissue, or can be derived from these VLCFAs. Their chains can be shortened, yielding propionyl-coenzyme A (CoA). Propionyl-CoA, by succinyl-CoA, can replenish the citric acid cycle (CAC) with anaplerotic intermediates and, thus, improve mitochondrial energy metabolism. Mitochondrial function is compromised in a number of disorders and may be impaired with increasing age. Optimizing anaplerotic intermediate availability for the CAC may help to cope with demands in times of increased metabolic stress and with aging. OCFAs may serve as substrates for synthesis of both odd-numbered VLCFAs and propionyl-CoA or store away excess propionic acid. PMID:27422507

Unsaturated fatty acids protect trophoblast cells from saturated fatty acid-induced autophagy defects.

PubMed

Hong, Ye-Ji; Ahn, Hyo-Ju; Shin, Jongdae; Lee, Joon H; Kim, Jin-Hoi; Park, Hwan-Woo; Lee, Sung Ki

2018-02-01

Dysregulated serum fatty acids are associated with a lipotoxic placental environment, which contributes to increased pregnancy complications via altered trophoblast invasion. However, the role of saturated and unsaturated fatty acids in trophoblastic autophagy has yet to be explored. Here, we demonstrated that prolonged exposure of saturated fatty acids interferes with the invasiveness of human extravillous trophoblasts. Saturated fatty acids (but not unsaturated fatty acids) inhibited the fusion of autophagosomes and lysosomes, resulting in the formation of intracellular protein aggregates. Furthermore, when the trophoblast cells were exposed to saturated fatty acids, unsaturated fatty acids counteracted the effects of saturated fatty acids by increasing degradation of autophagic vacuoles. Saturated fatty acids reduced the levels of the matrix metalloproteinases (MMP)-2 and MMP-9, while unsaturated fatty acids maintained their levels. In conclusion, saturated fatty acids induced decreased trophoblast invasion, of which autophagy dysfunction plays a major role. Copyright © 2017 Elsevier B.V. All rights reserved.

Chlorogenic acid versus amaranth's caffeoylisocitric acid - Gut microbial degradation of caffeic acid derivatives.

PubMed

Vollmer, Maren; Schröter, David; Esders, Selma; Neugart, Susanne; Farquharson, Freda M; Duncan, Sylvia H; Schreiner, Monika; Louis, Petra; Maul, Ronald; Rohn, Sascha

2017-10-01

The almost forgotten crop amaranth has gained renewed interest in recent years due to its immense nutritive potential. Health beneficial effects of certain plants are often attributed to secondary plant metabolites such as phenolic compounds. As these compounds undergo significant metabolism after consumption and are in most cases not absorbed very well, it is important to gain knowledge about absorption, biotransformation, and further metabolism in the human body. Whilst being hardly found in other edible plants, caffeoylisocitric acid represents the most abundant low molecular weight phenolic compound in many leafy amaranth species. Given that this may be a potentially bioactive compound, gastrointestinal microbial degradation of this substance was investigated in the present study by performing in vitro fermentation tests using three different fecal samples as inocula. The (phenolic) metabolites were analyzed using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Furthermore, quantitative polymerase chain reaction (qPCR) analyses were carried out to study the influence on the microbiome and its composition. The in vitro fermentations led to different metabolite profiles depending on the specific donor. For example, the metabolite 3-(4-hydroxyphenyl)propionic acid was observed in one fermentation as the main metabolite, whereas 3-(3-hydroxyphenyl)propionic acid was identified in the other fermentations as important. A significant change in selected microorganisms of the gut microbiota however was not detected. In conclusion, caffeoylisocitric acid from amaranth, which is a source of several esterified phenolic acids in addition to chlorogenic acid, can be metabolized by the human gut microbiota, but the metabolites produced vary between individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular complexes of alprazolam with carboxylic acids, boric acid, boronic acids, and phenols. Evaluation of supramolecular heterosynthons mediated by a triazole ring.

PubMed

Varughese, Sunil; Azim, Yasser; Desiraju, Gautam R

2010-09-01

A series of molecular complexes, both co-crystals and salts, of a triazole drug-alprazolam-with carboxylic acids, boric acid, boronic acids, and phenols have been analyzed with respect to heterosynthons present in the crystal structures. In all cases, the triazole ring behaves as an efficient hydrogen bond acceptor with the acidic coformers. The hydrogen bond patterns exhibited with aromatic carboxylic acids were found to depend on the nature and position of the substituents. Being a strong acid, 2,6-dihydroxybenzoic acid forms a salt with alprazolam. With aliphatic dicarboxylic acids alprazolam forms hydrates and the water molecules play a central role in synthon formation and crystal packing. The triazole ring makes two distinct heterosynthons in the molecular complex with boric acid. Boronic acids and phenols form consistent hydrogen bond patterns, and these are seemingly independent of the substitutional effects. Boronic acids form noncentrosymmetric cyclic synthons, while phenols form O--H...N hydrogen bonds with the triazole ring.

Degradation Studies of a Trimethylolpropane Triheptanoate Lubricant Basestock

DTIC Science & Technology

1977-12-01

primary dibasic acids : azelaic , adipic, glutaric, and sebacic. From this and subsequent investigations, a dibasic acid ester evolved which has been...Rotating Cylinder Deposition Rig-Parts List 13 2 Analysis for Parent Alcohols in (1-76-5 25 3 Analysis for Parent Acids in 0-76-5 27 4 Gas...formulations: (1) dibasic acid esters formed via esterification of dibasic fatty acids and monohydric alcohols, and (2) neopentyl polyol esters of monobasic

Nucleic Acid Immunity.

PubMed

Hartmann, G

2017-01-01

Organisms throughout biology need to maintain the integrity of their genome. From bacteria to vertebrates, life has established sophisticated mechanisms to detect and eliminate foreign genetic material or to restrict its function and replication. Tremendous progress has been made in the understanding of these mechanisms which keep foreign or unwanted nucleic acids from viruses or phages in check. Mechanisms reach from restriction-modification systems and CRISPR/Cas in bacteria and archaea to RNA interference and immune sensing of nucleic acids, altogether integral parts of a system which is now appreciated as nucleic acid immunity. With inherited receptors and acquired sequence information, nucleic acid immunity comprises innate and adaptive components. Effector functions include diverse nuclease systems, intrinsic activities to directly restrict the function of foreign nucleic acids (e.g., PKR, ADAR1, IFIT1), and extrinsic pathways to alert the immune system and to elicit cytotoxic immune responses. These effects act in concert to restrict viral replication and to eliminate virus-infected cells. The principles of nucleic acid immunity are highly relevant for human disease. Besides its essential contribution to antiviral defense and restriction of endogenous retroelements, dysregulation of nucleic acid immunity can also lead to erroneous detection and response to self nucleic acids then causing sterile inflammation and autoimmunity. Even mechanisms of nucleic acid immunity which are not established in vertebrates are relevant for human disease when they are present in pathogens such as bacteria, parasites, or helminths or in pathogen-transmitting organisms such as insects. This review aims to provide an overview of the diverse mechanisms of nucleic acid immunity which mostly have been looked at separately in the past and to integrate them under the framework nucleic acid immunity as a basic principle of life, the understanding of which has great potential to

Uric acid - urine

MedlinePlus

... this page: //medlineplus.gov/ency/article/003616.htm Uric acid urine test To use the sharing features on this page, please enable JavaScript. The uric acid urine test measures the level of uric acid ...

10-oxo-12(Z)-octadecenoic acid, a linoleic acid metabolite produced by gut lactic acid bacteria, potently activates PPARγ and stimulates adipogenesis

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

Goto, Tsuyoshi, E-mail: tgoto@kais.kyoto-u.ac.jp; Research Unit for Physiological Chemistry, The Center for the Promotion of Interdisciplinary Education and Research, Kyoto University; Kim, Young-Il

2015-04-17

Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increasedmore » adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism. - Highlights: • Most LA-derived fatty acids from gut lactic acid bacteria potently activated PPARα. • Among tested fatty acids, KetoA and KetoC significantly activated PPARγ. • KetoA induced adipocyte differentiation via the activation of PPARγ. • KetoA enhanced adiponectin production and glucose uptake during adipogenesis.« less

Bile acids: regulation of apoptosis by ursodeoxycholic acid

PubMed Central

Amaral, Joana D.; Viana, Ricardo J. S.; Ramalho, Rita M.; Steer, Clifford J.; Rodrigues, Cecília M. P.

2009-01-01

Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases. PMID:19417220

Bile acids: regulation of apoptosis by ursodeoxycholic acid.

PubMed

Amaral, Joana D; Viana, Ricardo J S; Ramalho, Rita M; Steer, Clifford J; Rodrigues, Cecília M P

2009-09-01

Bile acids are a group of molecular species of acidic steroids with peculiar physical-chemical and biological characteristics. At high concentrations they become toxic to mammalian cells, and their presence is pertinent in the pathogenesis of several liver diseases and colon cancer. Bile acid cytoxicity has been related to membrane damage, but also to nondetergent effects, such as oxidative stress and apoptosis. Strikingly, hydrophilic ursodeoxycholic acid (UDCA), and its taurine-conjugated form (TUDCA), show profound cytoprotective properties. Indeed, these molecules have been described as potent inhibitors of classic pathways of apoptosis, although their precise mode of action remains to be clarified. UDCA, originally used for cholesterol gallstone dissolution, is currently considered the first choice therapy for several forms of cholestatic syndromes. However, the beneficial effects of both UDCA and TUDCA have been tested in other experimental pathological conditions with deregulated levels of apoptosis, including neurological disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Here, we review the role of bile acids in modulating the apoptosis process, emphasizing the anti-apoptotic effects of UDCA and TUDCA, as well as their potential use as novel and alternate therapeutic agents for the treatment of apoptosis-related diseases.

The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro

PubMed Central

Carlsson, Johan A.; Wold, Agnes E.; Sandberg, Ann-Sofie; Östman, Sofia M.

2015-01-01

Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violetlow) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFNγ. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells. PMID:26619195

Oxidative cleavage of erucic acid for the synthesis of brassylic acid

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

Mohammed J. Nasrullah; Pooja Thapliyal; Erica N. Pfarr

2010-10-29

The main focus of this work is to synthesize Brassylic Acid (BA) using oxidative cleavage of Erucic Acid (EA). Crambe (Crambe abyssinica) is an industrial oilseed grown in North Dakota. Crambe has potential as an industrial fatty acid feedstock as a source of Erucic acid (EA). It has approximately 50-60 % of EA, a C{sub 22} monounsaturated fatty acid. Oxidative cleavage of unsaturated fatty acids derived from oilseeds produces long chain (9, 11, and 13 carbon atoms) dibasic and monobasic acids. These acids are known commercial feedstocks for the preparation of nylons, polyesters, waxes, surfactants, and perfumes. Other sources ofmore » EA are Rapeseed seed oil which 50-60 % of EA. Rapeseed is grown outside USA. The oxidative cleavage of EA was done using a high throughput parallel pressure reactor system. Kinetics of the reaction shows that BA yields reach a saturation at 12 hours. H{sub 2}WO{sub 4} was found to be the best catalyst for the oxidative cleavage of EA. High yields of BA were obtained at 80 C with bubbling of O{sub 2} or 10 bar of O{sub 2} for 12 hours.« less

Overview on mechanisms of acetic acid resistance in acetic acid bacteria.

PubMed

Wang, Bin; Shao, Yanchun; Chen, Fusheng

2015-02-01

Acetic acid bacteria (AAB) are a group of gram-negative or gram-variable bacteria which possess an obligate aerobic property with oxygen as the terminal electron acceptor, meanwhile transform ethanol and sugar to corresponding aldehydes, ketones and organic acids. Since the first genus Acetobacter of AAB was established in 1898, 16 AAB genera have been recorded so far. As the main producer of a world-wide condiment, vinegar, AAB have evolved an elegant adaptive system that enables them to survive and produce a high concentration of acetic acid. Some researches and reviews focused on mechanisms of acid resistance in enteric bacteria and made the mechanisms thoroughly understood, while a few investigations did in AAB. As the related technologies with proteome, transcriptome and genome were rapidly developed and applied to AAB research, some plausible mechanisms conferring acetic acid resistance in some AAB strains have been published. In this review, the related mechanisms of AAB against acetic acid with acetic acid assimilation, transportation systems, cell morphology and membrane compositions, adaptation response, and fermentation conditions will be described. Finally, a framework for future research for anti-acid AAB will be provided.

77 FR 3777 - Draft and Revised Draft Guidances for Industry Describing Product-Specific Bioequivalence...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-25

... Potassium (multiple RLDs) Aripiprazole Aspirin; Butalbital; Caffeine (multiple RLDs) Aspirin; Dipyridamole Aspirin; Oxycodone Aspirin; Butalbital; Caffeine; Codeine Phosphate Atovaquone Auranofin Azelaic Acid...

PlsX deletion impacts fatty acid synthesis and acid adaptation in Streptococcus mutans.

PubMed

Cross, Benjamin; Garcia, Ariana; Faustoferri, Roberta; Quivey, Robert G

2016-04-01

Streptococcus mutans, one of the primary causative agents of dental caries in humans, ferments dietary sugars in the mouth to produce organic acids. These acids lower local pH values, resulting in demineralization of the tooth enamel, leading to caries. To survive acidic environments, Strep. mutans employs several adaptive mechanisms, including a shift from saturated to unsaturated fatty acids in membrane phospholipids. PlsX is an acyl-ACP : phosphate transacylase that links the fatty acid synthase II (FASII) pathway to the phospholipid synthesis pathway, and is therefore central to the movement of unsaturated fatty acids into the membrane. Recently, we discovered that plsX is not essential in Strep. mutans. A plsX deletion mutant was not a fatty acid or phospholipid auxotroph. Gas chromatography of fatty acid methyl esters indicated that membrane fatty acid chain length in the plsX deletion strain differed from those detected in the parent strain, UA159. The deletion strain displayed a fatty acid shift similar to WT, but had a higher percentage of unsaturated fatty acids at low pH. The deletion strain survived significantly longer than the parent strain when cultures were subjected to an acid challenge of pH 2.5.The ΔplsX strain also exhibited elevated F-ATPase activity at pH 5.2, compared with the parent. These results indicate that the loss of plsX affects both the fatty acid synthesis pathway and the acid-adaptive response of Strep. mutans.

Molecular compositions and decadal trends of dicarboxylic acids, ketoacids, α-dicarbonyls in the marine aerosols from Chichi-Jima Island in the western North Pacific

NASA Astrophysics Data System (ADS)

Kawamura, K.; Tachibana, E.

2010-12-01

A rapid industrial development in China and East Asian countries for last two decades may have seriously changed the air quality of the North Pacific. To better understand a long-term atmospheric changes of organic aerosols in the western North Pacific, we collected marine aerosol samples on weekly basis at a remote island, Chichijima (27°04'E; 142°13'N) in 2001-2010. The island is located in the boundary of westerly and easterly wind regimes. The aerosol samples were analyzed for dicarboxylic acids, ketoacids and α-dicarbonyls employing butyl ester derivatization followed by GC determination, together with total carbon (TC) and water-soluble organic carbon (WSOC). Homologous series of saturated diacids (C2-C11) were detected with a predominance of oxalic (C2) acid followed by malonic (C3) and succinic (C4) acids. Unsaturated diacids, including maleic (M), fumaric (F), phthalic, and iso-/tere-phthalic acids, were also detected together with ketoacids and α-dicarbonyls. Concentrations of total diacids fluctuated significantly in a range of 10-600 ngm-3 with winter/spring maximum and summer minimum. The maximum was explained by a combination of enhanced emissions of polluted aerosols and their precursors in Asia and enhanced atmospheric transport to the North Pacific due to the intensified westerly winds in winter/spring. Concentration ratios of C3 to C4 diacid (range 0.2-28, av. 2.8) showed a maximum during summer, indicating more oxidation of longer-chain diacids to shorter ones. Azelaic acid (C9) that is a specific photo-oxidation product of unsaturated fatty acid such as oleic acid showed a sharp increase relative to other diacids in summer, suggesting enhanced sea-to-air emission of unsaturated fatty acids followed by photochemical oxidation during summer. On the other hand, M/F ratios (range 0-8.7, av. 1.1) significantly decreased from winter to summer due to photochemical cis-to-trans isomerization. We also discuss decadal trends in the concentrations of

Production of γ-linolenic acid and stearidonic acid by Synechococcus sp. PCC7002 containing cyanobacterial fatty acid desaturase genes

NASA Astrophysics Data System (ADS)

Dong, Xuewei; He, Qingfang; Peng, Zhenying; Yu, Jinhui; Bian, Fei; Li, Youzhi; Bi, Yuping

2016-07-01

Genetic modification is useful for improving the nutritional qualities of cyanobacteria. To increase the total unsaturated fatty acid content, along with the ratio of ω-3/ω-6 fatty acids, genetic engineering can be used to modify fatty acid metabolism. Synechococcus sp. PCC7002, a fast-growing cyanobacterium, does not contain a Δ6 desaturase gene and is therefore unable to synthesize γ-linolenic acid (GLA) and stearidonic acid (SDA), which are important in human health. In this work, we constructed recombinant vectors Syd6D, Syd15D and Syd6Dd15D to express the Δ15 desaturase and Δ6 desaturase genes from Synechocystis PCC6803 in Synechococcus sp. PCC7002, with the aim of expressing polyunsaturated fatty acids. Overexpression of the Δ15 desaturase gene in Synechococcus resulted in 5.4 times greater accumulation of α-linolenic acid compared with the wild-type while Δ6 desaturase gene expression produced both GLA and SDA. Co-expression of the two genes resulted in low-level accumulation of GLA but much larger amounts of SDA, accounting for as much to 11.64% of the total fatty acid content.

Utilization of acidic α-amino acids as acyl donors: an effective stereo-controllable synthesis of aryl-keto α-amino acids and their derivatives.

PubMed

Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Tachrim, Zetryana Puteri; Hashidoko, Yasuyuki; Hashimoto, Makoto

2014-05-16

Aryl-keto-containing α-amino acids are of great importance in organic chemistry and biochemistry. They are valuable intermediates for the construction of hydroxyl α-amino acids, nonproteinogenic α-amino acids, as well as other biofunctional components. Friedel-Crafts acylation is an effective method to prepare aryl-keto derivatives. In this review, we summarize the preparation of aryl-keto containing α-amino acids by Friedel-Crafts acylation using acidic α-amino acids as acyl-donors and Lewis acids or Brönsted acids as catalysts.

Dicarboxylic acids generated by thermal alteration of kerogen and humic acids

NASA Technical Reports Server (NTRS)

Kawamura, Kimitaka; Kaplan, I. R.

1987-01-01

Significant amounts (up to 2 percent of organic geopolymers) of low-molecular-weight (LMW) dicarboxylic acids (C2-C10) have been detected during thermal alteration (270 C, 2 h) of kerogens and humic acids isolated from young or ancient lithified sediments. Their distribution is characterized by the predominance of oxalic acid followed by succinic, fumaric, and methylsuccinic acids. These acids are probably released by the breakdown of macromolecular structures, which have incorporated biogenic organic compounds, including diacids, during early digenesis in sediments. Because of their reactivity, LMW diacids may play geochemically important roles under natural conditions.

Glutamic Acid as a Precursor to N-Terminal Pyroglutamic Acid in Mouse Plasmacytoma Protein

PubMed Central

Twardzik, Daniel R.; Peterkofsky, Alan

1972-01-01

Cell suspensions derived from a mouse plasmacytoma (RPC-20) that secretes an immunoglobulin light chain containing N-terminal pyroglutamic acid can synthesize protein in vitro. Chromatographic examination of an enzymatic digest of protein labeled with glutamic acid shows only labeled glutamic acid and pyroglutamic acid; hydrolysis of protein from cells labeled with glutamine, however, yields substantial amounts of glutamic acid in addition to glutamine and pyroglutamic acid. The absence of glutamine synthetase and presence of glutaminase in plasmacytoma homogenates is consistent with these findings. These data indicate that N-terminal pyroglutamic acid can be derived from glutamic acid without prior conversion of glutamic acid to glutamine. Since free or bound forms of glutamine cyclize nonezymatically to pyroglutamate with ease, while glutamic acid does not, the data suggest that N-terminal pyroglutamic acid formation from glutamic acid is enzymatic rather than spontaneous. Images PMID:4400295

Microorganisms for producing organic acids

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

Pfleger, Brian Frederick; Begemann, Matthew Brett

Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

Microorganisms for producing organic acids

DOEpatents

Pfleger, Brian Frederick; Begemann, Matthew Brett

2014-09-30

Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

Manipulating Membrane Fatty Acid Compositions of Whole Plants with Tween-Fatty Acid Esters 1

PubMed Central

Terzaghi, William B.

1989-01-01

This paper describes a method for manipulating plant membrane fatty acid compositions without altering growth temperature or other conditions. Tween-fatty acid esters carrying specific fatty acids were synthesized and applied to various organs of plants growing axenically in glass jars. Treated plants incorporated large amounts of exogenous fatty acids into all acylated membrane lipids detected. Fatty acids were taken up by both roots and leaves. Fatty acids applied to roots were found in leaves, while fatty acids applied to leaves appeared in both leaves higher on the plant and in roots, indicating translocation (probably in the phloem). Foliar application was most effective; up to 20% of membrane fatty acids of leaves above the treated leaf and up to 40% of root membrane fatty acids were exogenously derived. Plants which took up exogenous fatty acids changed their patterns of fatty acid synthesis such that ratios of saturated to unsaturated fatty acids remained essentially unaltered. Fatty acid uptake was most extensively studied in soybean (Glycine max [L.] Merr.), but was also observed in other species, including maize (Zea mays L.), mung beans (Vigna radiata L.), peas (Pisum sativum L.), petunia (Petunia hybrida L.) and tomato (Lycopersicon esculentum Mill.). Potential applications of this system include studying internal transport of fatty acids, regulation of fatty acid and membrane synthesis, and influences of membrane fatty acid composition on plant physiology. Images Figure 2 PMID:16666997

Acid Thunder: Acid Rain and Ancient Mesoamerica

ERIC Educational Resources Information Center

Kahl, Jonathan D. W.; Berg, Craig A.

2006-01-01

Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

College Chemistry Students' Mental Models of Acids and Acid Strength

ERIC Educational Resources Information Center

McClary, LaKeisha; Talanquer, Vicente

2011-01-01

The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research…

Microwave-Assisted Extraction of Oleanolic Acid and Ursolic Acid from Ligustrum lucidum Ait

PubMed Central

Xia, En-Qin; Wang, Bo-Wei; Xu, Xiang-Rong; Zhu, Li; Song, Yang; Li, Hua-Bin

2011-01-01

Oleanolic acid and ursolic acid are the main active components in fruit of Ligustrum lucidum Ait, and possess anticancer, antimutagenic, anti-inflammatory, antioxidative and antiprotozoal activities. In this study, microwave-assisted extraction of oleanolic acid and ursolic acid from Ligustrum lucidum was investigated with HPLC-photodiode array detection. Effects of several experimental parameters, such as type and concentration of extraction solvent, ratio of liquid to material, microwave power, extraction temperature and microwave time, on the extraction efficiencies of oleanolic acid and ursolic acid from Ligustrum lucidum were evaluated. The influence of experimental parameters on the extraction efficiency of ursolic acid was more significant than that of oleanolic acid (p < 0.05). The optimal extraction conditions were 80% ethanol aqueous solution, the ratio of material to liquid was 1:15, and extraction for 30 min at 70 °C under microwave irradiation of 500 W. Under optimal conditions, the yields of oleanolic acid and ursolic acid were 4.4 ± 0.20 mg/g and 5.8 ± 0.15 mg/g, respectively. The results obtained are helpful for the full utilization of Ligustrum lucidum, which also indicated that microwave-assisted extraction is a very useful method for extraction of oleanolic acid and ursolic acid from plant materials. PMID:21954361

Chlorogenic acids and the acyl-quinic acids: discovery, biosynthesis, bioavailability and bioactivity.

PubMed

Clifford, Michael N; Jaganath, Indu B; Ludwig, Iziar A; Crozier, Alan

2017-12-13

Covering: 2000 up to late 2017This review is focussed upon the acyl-quinic acids, the most studied group within the ca. 400 chlorogenic acids so far reported. The acyl-quinic acids, the first of which was characterised in 1846, are a diverse group of plant-derived compounds produced principally through esterification of an hydroxycinnamic acid and 1l-(-)-quinic acid. Topics addressed in this review include the confusing nomenclature, quantification and characterisation by NMR and MS, biosynthesis and role in planta, and the occurrence of acyl-quinic acids in coffee, their transformation during roasting and delivery to the beverage. Coffee is the major human dietary source world-wide of acyl-quinic acids and consideration is given to their absorption and metabolism in the upper gastrointestinal tract, and the colon where the microbiota play a key role in the formation of catabolites. Evidence on the potential of the in vivo metabolites and catabolites of acyl-quinic acids to promote the consumer's health is evaluated.

SYNTHETIC LUBRICANTS

DTIC Science & Technology

azelaic , and sebacic acids are the most readily available dibasic acids suitable for ester lubricant production, while the petroleum derived Oxo alcohols...of synthetic lubricants for use at low and high temperatures. The diesters of straight-chain dibasic acids lead the field of esters mutable as...dibasic acid esters in all the characteristics studied so far, and this type of ester therefore represents a promising source of synthetic oil. Mono

40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acid polyamine condensate... New Uses for Specific Chemical Substances § 721.6200 Fatty acid polyamine condensate, phosphoric acid... substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and P-90-1985...

40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acid polyamine condensate... New Uses for Specific Chemical Substances § 721.6200 Fatty acid polyamine condensate, phosphoric acid... substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and P-90-1985...

Amino acids

MedlinePlus

... this page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

Method for distinctive estimation of stored acidity forms in acid mine wastes.

PubMed

Li, Jun; Kawashima, Nobuyuki; Fan, Rong; Schumann, Russell C; Gerson, Andrea R; Smart, Roger St C

2014-10-07

Jarosites and schwertmannite can be formed in the unsaturated oxidation zone of sulfide-containing mine waste rock and tailings together with ferrihydrite and goethite. They are also widely found in process wastes from electrometallurgical smelting and metal bioleaching and within drained coastal lowland soils (acid-sulfate soils). These secondary minerals can temporarily store acidity and metals or remove and immobilize contaminants through adsorption, coprecipitation, or structural incorporation, but release both acidity and toxic metals at pH above about 4. Therefore, they have significant relevance to environmental mineralogy through their role in controlling pollutant concentrations and dynamics in contaminated aqueous environments. Most importantly, they have widely different acid release rates at different pHs and strongly affect drainage water acidity dynamics. A procedure for estimation of the amounts of these different forms of nonsulfide stored acidity in mining wastes is required in order to predict acid release rates at any pH. A four-step extraction procedure to quantify jarosite and schwertmannite separately with various soluble sulfate salts has been developed and validated. Corrections to acid potentials and estimation of acid release rates can be reliably based on this method.

Amino acid catabolism and generation of volatiles by lactic acid bacteria.

PubMed

Tavaria, F K; Dahl, S; Carballo, F J; Malcata, F X

2002-10-01

Twelve isolates of lactic acid bacteria, belonging to the Lactobacillus, Lactococcus, Leuconostoc, and Enterococcus genera, were previously isolated from 180-d-old Serra da Estrela cheese, a traditional Portuguese cheese manufactured from raw milk and coagulated with a plant rennet. These isolates were subsequently tested for their ability to catabolize free amino acids, when incubated independently with each amino acid in free form or with a mixture thereof. Attempts were made in both situations to correlate the rates of free amino acid uptake with the numbers of viable cells. When incubated individually, leucine, valine, glycine, aspartic acid, serine, threonine, lysine, glutamic acid, and alanine were degraded by all strains considered; arginine tended to build up, probably because of transamination of other amino acids. When incubated together, the degradation of free amino acids by each strain was dependent on pH (with an optimum pH around 6.0). The volatiles detected in ripened Serra da Estrela cheese originated mainly from leucine, phenylalanine, alanine, and valine, whereas in vitro they originated mainly from valine, phenylalanine, serine, leucine, alanine, and threonine. The wild strains tested offer a great potential for flavor generation, which might justify their inclusion in a tentative starter/nonstarter culture for that and similar cheeses.

Combination of aspartic acid and glutamic acid inhibits tumor cell proliferation.

PubMed

Yamaguchi, Yoshie; Yamamoto, Katsunori; Sato, Yoshinori; Inoue, Shinjiro; Morinaga, Tetsuo; Hirano, Eiichi

2016-01-01

Placental extract contains several biologically active compounds, and pharmacological induction of placental extract has therapeutic effects, such as improving liver function in patients with hepatitis or cirrhosis. Here, we searched for novel molecules with an anti-tumor activity in placental extracts. Active molecules were separated by chromatographic analysis, and their antiproliferative activities were determined by a colorimetric assay. We identified aspartic acid and glutamic acid to possess the antiproliferative activity against human hepatoma cells. Furthermore, we showed that the combination of aspartic acid and glutamic acid exhibited enhanced antiproliferative activity, and inhibited Akt phosphorylation. We also examined in vivo tumor inhibition activity using the rabbit VX2 liver tumor model. The treatment mixture (emulsion of the amino acids with Lipiodol) administered by hepatic artery injection inhibited tumor cell growth of the rabbit VX2 liver. These results suggest that the combination of aspartic acid and glutamic acid may be useful for induction of tumor cell death, and has the potential for clinical use as a cancer therapeutic agent.

Health benefits of n-3 polyunsaturated fatty acids: eicosapentaenoic acid and docosahexaenoic acid.

PubMed

Siriwardhana, Nalin; Kalupahana, Nishan S; Moustaid-Moussa, Naima

2012-01-01

Marine-based fish and fish oil are the most popular and well-known sources of n-3 polyunsaturated fatty acids (PUFAs), namely, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These n-3 PUFAs are known to have variety of health benefits against cardiovascular diseases (CVDs) including well-established hypotriglyceridemic and anti-inflammatory effects. Also, various studies indicate promising antihypertensive, anticancer, antioxidant, antidepression, antiaging, and antiarthritis effects. Moreover, recent studies also indicate anti-inflammatory and insulin-sensitizing effects of these fatty acids in metabolic disorders. Classically, n-3 PUFAs mediate some of these effects by antagonizing n-6 PUFA (arachidonic acid)-induced proinflammatory prostaglandin E₂ (PGE₂) formation. Another well-known mechanism by which n-3 PUFAs impart their anti-inflammatory effects is via reduction of nuclear factor-κB activation. This transcription factor is a potent inducer of proinflammatory cytokine production, including interleukin 6 and tumor necrosis factor-α, both of which are decreased by EPA and DHA. Other evidence also demonstrates that n-3 PUFAs repress lipogenesis and increase resolvins and protectin generation, ultimately leading to reduced inflammation. Finally, beneficial effects of EPA and DHA in insulin resistance include their ability to increase secretion of adiponectin, an anti-inflammatory adipokine. In summary, n-3 PUFAs have multiple health benefits mediated at least in part by their anti-inflammatory actions; thus their consumption, especially from dietary sources, should be encouraged. Copyright © 2012 Elsevier Inc. All rights reserved.

Free lactic acid production under acidic conditions by lactic acid bacteria strains: challenges and future prospects.

PubMed

Singhvi, Mamata; Zendo, Takeshi; Sonomoto, Kenji

2018-05-26

Lactic acid (LA) is an important platform chemical due to its significant applications in various fields and its use as a monomer for the production of biodegradable poly(lactic acid) (PLA). Free LA production is required to get rid of CaSO 4 , a waste material produced during fermentation at neutral pH which will lead to easy purification of LA required for the production of biodegradable PLA. Additionally, there is no need to use corrosive acids to release free LA from the calcium lactate produced during neutral fermentation. To date, several attempts have been made to improve the acid tolerance of lactic acid bacteria (LAB) by using both genome-shuffling approaches and rational design based on known mechanisms of LA tolerance and gene deletion in yeast strains. However, the lack of knowledge and the complexity of acid-tolerance mechanisms have made it challenging to generate LA-tolerant strains by simply modifying few target genes. Currently, adaptive evolution has proven an efficient strategy to improve the LA tolerance of individual/engineered strains. The main objectives of this article are to summarize the conventional biotechnological LA fermentation processes to date, assess their overall economic and environmental cost, and to introduce modern LA fermentation strategies for free LA production. In this review, we provide a broad overview of free LA fermentation processes using robust LAB that can ferment in acidic environments, the obstacles to these processes and their possible solutions, and the impact on future development of free LA fermentation processes commercially.

Valproic Acid

MedlinePlus

... and spinal cord and can also cause lower intelligence in babies exposed to valproic acid before birth. ... acid. Talk to your doctor about birth control methods that will work for you. If you become ...

Docosahexaenoic acid synthesis from n-3 fatty acid precursors in rat hippocampal neurons.

PubMed

Kaduce, Terry L; Chen, Yucui; Hell, Johannes W; Spector, Arthur A

2008-05-01

Docosahexaenoic acid (DHA), the most abundant n-3 polyunsaturated fatty acid in the brain, has important functions in the hippocampus. To better understand essential fatty acid homeostasis in this region of the brain, we investigated the contributions of n-3 fatty acid precursors in supplying hippocampal neurons with DHA. Primary cultures of rat hippocampal neurons incorporated radiolabeled 18-, 20-, 22-, and 24-carbon n-3 fatty acid and converted some of the uptake to DHA, but the amounts produced from either [1-14C]alpha-linolenic or [1-14C]eicosapentaenoic acid were considerably less than the amounts incorporated when the cultures were incubated with [1-14C]22:6n-3. Most of the [1-14C]22:6n-3 uptake was incorporated into phospholipids, primarily ethanolamine phosphoglycerides. Additional studies demonstrated that the neurons converted [1-14C]linoleic acid to arachidonic acid, the main n-6 fatty acid in the brain. These findings differ from previous results indicating that cerebral and cerebellar neurons cannot convert polyunsaturated fatty acid precursors to DHA or arachidonic acid. Fatty acid compositional analysis demonstrated that the hippocampal neurons contained only 1.1-2.5 mol% DHA under the usual low-DHA culture conditions. The relatively low-DHA content suggests that some responses obtained with these cultures may not be representative of neuronal function in the brain.

Kinetics of browning and correlations between browning degree and pyrazine compounds in l-ascorbic acid/acidic amino acid model systems.

PubMed

Yu, Ai-Nong; Zhou, Yong-Yan; Yang, Yi-Ni

2017-04-15

The kinetics of browning and the correlation between browning products (BPs) and pyrazine compounds were investigated by heating equimolar l-ascorbic acid (ASA)/acidic amino acids under weak alkaline conditions at 120-150°C for 10-120min. The formations of BPs and pyrazine compounds from the reaction were monitored by UV-vis and SPME-GC-FID, respectively. The formation of BPs in both ASA/l-glutamic acid and ASA/l-aspartic acid model reaction systems followed zero order reaction kinetics with activation energies (E a ) of 90.13 and 93.38kJ/mol, respectively. ASA/l-aspartic acid browned at a slightly higher rate than ASA/l-glutamic acid. The total concentration of pyrazine compounds was highly and positively correlated with that of BPs. Based on the observed kinetic data, the formation mechanisms of BPs and pyrazine compounds were proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Method of increasing conversion of a fatty acid to its corresponding dicarboxylic acid

DOEpatents

Craft, David L.; Wilson, C. Ron; Eirich, Dudley; Zhang, Yeyan

2004-09-14

A nucleic acid sequence including a CYP promoter operably linked to nucleic acid encoding a heterologous protein is provided to increase transcription of the nucleic acid. Expression vectors and host cells containing the nucleic acid sequence are also provided. The methods and compositions described herein are especially useful in the production of polycarboxylic acids by yeast cells.

The interaction of albumin and fatty-acid-binding protein with membranes: oleic acid dissociation.

PubMed

Catalá, A

1984-10-01

Bovine serum albumin or fatty-acid-binding protein rapidly lose oleic acid when incubated in the presence of dimyristoyl lecithin liposomes. The phenomenon is dependent on vesicle concentration and no measurable quantities of protein are found associated with liposomes. Upon gel filtration on Sepharose CL-2B of incubated mixtures of microsomes containing [1-14C] oleic acid and albumin or fatty-acid-binding protein, association of fatty acid with the soluble proteins could be demonstrated. Both albumin and fatty-acid-binding protein stimulated the transfer of oleic acid from rat liver microsomes to egg lecithin liposomes. These results indicate that albumin is more effective in the binding of oleic acid than fatty-acid-binding protein, which allows a selective oleic acid dissociation during its interaction with membranes.

Reciprocal effects of 5-(tetradecyloxy)-2-furoic acid on fatty acid oxidation.

PubMed

Otto, D A; Chatzidakis, C; Kasziba, E; Cook, G A

1985-10-01

Under certain incubation conditions 5-(tetradecyloxy)-2-furoic acid (TOFA) stimulated the oxidation of palmitate by hepatocytes, as observed by others. A decrease in malonyl-CoA concentration accompanied the stimulation of oxidation. Under other conditions, however, TOFA inhibited fatty acid oxidation. The observed effects of TOFA depended on the TOFA and fatty acid concentrations, the cell concentration, the time of TOFA addition relative to the addition of fatty acid, and the nutritional state of the animal (fed or starved). The data indicate that only under limited incubation conditions may TOFA be used as an inhibitor of fatty acid synthesis without inhibition of fatty acid oxidation. When rat liver mitochondria were preincubated with TOFA, ketogenesis from palmitate was slightly inhibited (up to 20%) at TOFA concentrations that were less than that of CoA, but the inhibition became almost complete (up to 90%) when TOFA was greater than or equal to the CoA concentration. TOFA had only slight or no inhibitory effects on the oxidation of palmitoyl-CoA, palmitoyl(-)carnitine, or butyrate. Since TOFA can be converted to TOFyl-CoA, the data suggest that the inhibition of fatty acid oxidation from palmitate results from the decreased availability of CoA for extramitochondrial activation of fatty acids. These data, along with previous data of others, indicate that inhibition of fatty acid oxidation by CoA sequestration is a common mechanism of a group of carboxylic acid inhibitors. A general caution is appropriate with regard to the interpretation of results when using TOFA in studies of fatty acid oxidation.

Structure-activity relationship investigation of tertiary amine derivatives of cinnamic acid as acetylcholinesterase and butyrylcholinesterase inhibitors: compared with that of phenylpropionic acid, sorbic acid and hexanoic acid.

PubMed

Gao, Xiaohui; Tang, Jingjing; Liu, Haoran; Liu, Linbo; Kang, Lu; Chen, Wen

2018-12-01

In the present investigation, 48 new tertiary amine derivatives of cinnamic acid, phenylpropionic acid, sorbic acid and hexanoic acid (4d-6g, 10d-12g, 16d-18g and 22d-24g) were designed, synthesized and evaluated for the effect on AChE and BChE in vitro. The results revealed that the alteration of aminoalkyl types and substituted positions markedly influences the effects in inhibiting AChE. Almost of all cinnamic acid derivatives had the most potent inhibitory activity than that of other acid derivatives with the same aminoalkyl side chain. Unsaturated bond and benzene ring in cinnamic acid scaffold seems important for the inhibitory activity against AChE. Among them, compound 6g revealed the most potent AChE inhibitory activity (IC 50 value: 3.64 µmol/L) and highest selectivity over BChE (ratio: 28.6). Enzyme kinetic study showed that it present a mixed-type inhibition against AChE. The molecular docking study suggested that it can bind with the catalytic site and peripheral site of AChE.

Trans Fatty Acids

NASA Astrophysics Data System (ADS)

Doyle, Ellin

1997-09-01

Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.

Fatty acid-producing hosts

DOEpatents

Pfleger, Brian F; Lennen, Rebecca M

2013-12-31

Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at 37.degree. C. Methods of producing a fatty acid product comprising culturing such hosts at 37.degree. C. are also described.

Polydopamine-coated magnetic molecularly imprinted polymer for the selective solid-phase extraction of cinnamic acid, ferulic acid and caffeic acid from radix scrophulariae sample.

PubMed

Yin, Yuli; Yan, Liang; Zhang, Zhaohui; Wang, Jing; Luo, Ningjing

2016-04-01

We describe novel cinnamic acid polydopamine-coated magnetic imprinted polymers for the simultaneous selective extraction of cinnamic acid, ferulic acid and caffeic acid from radix scrophulariae sample. The novel magnetic imprinted polymers were synthesized by surface imprinting polymerization using magnetic multi-walled carbon nanotubes as the support material, cinnamic acid as the template and dopamine as the functional monomer. The magnetic imprinted polymers were characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and vibrating sample magnetometry. The results revealed that the magnetic imprinted polymers had outstanding magnetic properties, high adsorption capacity, selectivity and fast kinetic binding toward cinnamic acid, ferulic acid and caffeic acid. Coupled with high-performance liquid chromatography, the extraction conditions of the magnetic imprinted polymers as a magnetic solid-phase extraction sorbent were investigated in detail. The proposed imprinted magnetic solid phase extraction procedure has been used for the purification and enrichment of cinnamic acid, ferulic acid and caffeic acid successfully from radix scrophulariae extraction sample with recoveries of 92.4-115.0% for cinnamic acid, 89.4-103.0% for ferulic acid and 86.6-96.0% for caffeic acid. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aminocaproic Acid

MedlinePlus

Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This ... before the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

Fatty Acids of Myxococcus xanthus

PubMed Central

Ware, Judith C.; Dworkin, Martin

1973-01-01

Fatty acids were extracted from saponified vegetative cells and myxospores of Myxococcus xanthus and examined as the methyl esters by gas-liquid chromatography. The acids consisted mainly of C14 to C17 species. Branched acids predominated, and iso-pentadecanoic acid constituted half or more of the mixture. The other leading component (11–28%) was found to be 11-n-hexadecenoic acid. Among the unsaturated acids were two diunsaturated ones, an n-hexadecadienoic acid and an iso-heptadecadienoic acid. No significant differences between the fatty acid compositions of the vegetative cells and myxospores could be detected. The fatty acid composition of M. xanthus was found to be markedly similar to that of Stigmatella aurantiaca. It is suggested that a fatty acid pattern consisting of a large proportion of iso-branched C15 and C17 acids and a substantial amount of an n-16:1 acid is characteristic of myxobacteria. PMID:4197903

Secular trend of serum docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid concentrations among Japanese-a 4- and 13-year descriptive epidemiologic study.

PubMed

Otsuka, Rei; Kato, Yuki; Imai, Tomoko; Ando, Fujiko; Shimokata, Hiroshi

2015-03-01

Cross-sectional studies have shown age-related increases in blood docosahexaenoic and eicosapentaenoic acid and decreases in arachidonic acid. We describe serum docosahexaenoic, eicosapentaenoic, and arachidonic acid concentrations over 13 years (1997-2012) across four study waves and serum fatty acid composition over 4 years (2006-2012) between two study waves according to age groups by sex in the same subjects. We included 443 men and 435 women aged 40-79 years at baseline. Serum arachidonic acid concentrations increased in all sex and age groups over 13 years, and eicosapentaenoic or docosahexaenoic acid concentrations increased in males and females who were younger and middle-aged at baseline. Only serum arachidonic acid composition increased over 4 years in men and women who were 40-69 years at baseline, even after adjustment for arachidonic acid intake. These findings suggest a secular increase trend in serum arachidonic acid levels over 13 years among randomly selected community-dwelling middle-aged and elderly Japanese. Copyright © 2014 Elsevier Ltd. All rights reserved.

The use of lactic acid-producing, malic acid-producing, or malic acid-degrading yeast strains for acidity adjustment in the wine industry.

PubMed

Su, Jing; Wang, Tao; Wang, Yun; Li, Ying-Ying; Li, Hua

2014-03-01

In an era of economic globalization, the competition among wine businesses is likely to get tougher. Biotechnological innovation permeates the entire world and intensifies the severity of the competition of the wine industry. Moreover, modern consumers preferred individualized, tailored, and healthy and top quality wine products. Consequently, these two facts induce large gaps between wine production and wine consumption. Market-orientated yeast strains are presently being selected or developed for enhancing the core competitiveness of wine enterprises. Reasonable biological acidity is critical to warrant a high-quality wine. Many wild-type acidity adjustment yeast strains have been selected all over the world. Moreover, mutation breeding, metabolic engineering, genetic engineering, and protoplast fusion methods are used to construct new acidity adjustment yeast strains to meet the demands of the market. In this paper, strategies and concepts for strain selection or improvement methods were discussed, and many examples based upon selected studies involving acidity adjustment yeast strains were reviewed. Furthermore, the development of acidity adjustment yeast strains with minimized resource inputs, improved fermentation, and enological capabilities for an environmentally friendly production of healthy, top quality wine is presented.

Structural studies of crystalline forms of triamterene with carboxylic acid, GRAS and API molecules

PubMed Central

Rehman, Abida

2018-01-01

Pharmaceutical salt solvates (dimethyl sulfoxide, DMSO) of the drug triamterene with the coformers acetic, succinic, adipic, pimelic, azelaic and nicotinic acid and ibuprofen are prepared by liquid-assisted grinding and solvent-evaporative crystallization. The modified ΔpK a rule as proposed by Cruz-Cabeza [(2012 ▸). CrystEngComm, 14, 6362–6365] is in close agreement with the results of this study. All adducts were characterized by X-ray diffraction and thermal analytical techniques, including single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry and thermal gravimetric analysis. Hydrogen-bonded motifs combined to form a variety of extended tapes and sheets. Analysis of the crystal structures showed that all adducts existed as salt solvates and contained the amino­pyridinium–carboxyl­ate heterodimer, except for the solvate containing triamterene, ibuprofen and DMSO, as a result of the presence of a strong and stable hemitriamterenium duplex. A search of the Cambridge Structural Database (CSD 5.36, Version 1.18) to determine the frequency of occurrence of the putative supramolecular synthons found in this study showed good agreement with previous work. PMID:29755747

Inhibition studies of soybean (Glycine max) urease with heavy metals, sodium salts of mineral acids, boric acid, and boronic acids.

PubMed

Kumar, Sandeep; Kayastha, Arvind M

2010-10-01

Various inhibitors were tested for their inhibitory effects on soybean urease. The K(i) values for boric acid, 4-bromophenylboronic acid, butylboronic acid, and phenylboronic acid were 0.20 +/- 0.05 mM, 0.22 +/- 0.04 mM, 1.50 +/- 0.10 mM, and 2.00 +/- 0.11 mM, respectively. The inhibition was competitive type with boric acid and boronic acids. Heavy metal ions including Ag(+), Hg(2+), and Cu(2+) showed strong inhibition on soybean urease, with the silver ion being a potent inhibitor (IC(50) = 2.3 x 10(-8) mM). Time-dependent inhibition studies exhibited biphasic kinetics with all heavy metal ions. Furthermore, inhibition studies with sodium salts of mineral acids (NaF, NaCl, NaNO(3), and Na(2)SO(4)) showed that only F(-) inhibited soybean urease significantly (IC(50) = 2.9 mM). Competitive type of inhibition was observed for this anion with a K(i) value of 1.30 mM.

Citric acid urine test

MedlinePlus

Urine - citric acid test; Renal tubular acidosis - citric acid test; Kidney stones - citric acid test; Urolithiasis - citric acid test ... No special preparation is necessary for this test. But the results ... test is usually done while you are on a normal diet. Ask your ...

Profile of preoperative fecal organic acids closely predicts the incidence of postoperative infectious complications after major hepatectomy with extrahepatic bile duct resection: Importance of fecal acetic acid plus butyric acid minus lactic acid gap.

PubMed

Yokoyama, Yukihiro; Mizuno, Takashi; Sugawara, Gen; Asahara, Takashi; Nomoto, Koji; Igami, Tsuyoshi; Ebata, Tomoki; Nagino, Masato

2017-10-01

To investigate the association between preoperative fecal organic acid concentrations and the incidence of postoperative infectious complications in patients undergoing major hepatectomy with extrahepatic bile duct resection for biliary malignancies. The fecal samples of 44 patients were collected before undergoing hepatectomy with bile duct resection for biliary malignancies. The concentrations of fecal organic acids, including acetic acid, butyric acid, and lactic acid, and representative fecal bacteria were measured. The perioperative clinical characteristics and the concentrations of fecal organic acids were compared between patients with and without postoperative infectious complications. Among 44 patients, 13 (30%) developed postoperative infectious complications. Patient age and intraoperative bleeding were significantly greater in patients with postoperative infectious complications compared with those without postoperative infectious complications. The concentrations of fecal acetic acid and butyric acid were significantly less, whereas the concentration of fecal lactic acid tended to be greater in the patients with postoperative infectious complications. The calculated gap between the concentrations of fecal acetic acid plus butyric acid minus lactic acid gap was less in the patients with postoperative infectious complications (median 43.5 vs 76.1 μmol/g of feces, P = .011). Multivariate analysis revealed that an acetic acid plus butyric acid minus lactic acid gap <60 μmol/g was an independent risk factor for postoperative infectious complications with an odds ratio of 15.6; 95% confidence interval 1.8-384.1. The preoperative fecal organic acid profile (especially low acetic acid, low butyric acid, and high lactic acid) had a clinically important impact on the incidence of postoperative infectious complications in patients undergoing major hepatectomy with extrahepatic bile duct resection. Copyright © 2017. Published by Elsevier Inc.

Highly Selective Deoxydehydration of Tartaric Acid over Supported and Unsupported Rhenium Catalysts with Modified Acidities.

PubMed

Li, Xiukai; Zhang, Yugen

2016-10-06

The deoxydehydration (DODH) of sugar acids to industrially important carboxylic acids is a very attractive topic. Oxorhenium complexes are the most-often employed DODH catalysts. Because of the acidity of the rhenium catalysts, the DODH products of sugar acids were usually in the form of mixture of free carboxylic acids and esters. Herein, we demonstrate strategies for the selective DODH of sugar acids to free carboxylic acids by tuning the Lewis acidity or the Brønsted acidity of the rhenium-based catalysts. Starting from tartaric acid, up to 97 % yield of free maleic acid was achieved. Based on our strategies, functional polymer immobilized heterogeneous rhenium catalysts were also developed for the selective DODH conversion of sugar acids. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

STIMULATION OF FUNDULUS BY HYDROCHLORIC AND FATTY ACIDS IN FRESH WATER, AND BY FATTY ACIDS, MINERAL ACIDS, AND THE SODIUM SALTS OF MINERAL ACIDS IN SEA WATER

PubMed Central

Allison, J. B.; Cole, William H.

1934-01-01

1. Fundulus heteroclitus was found to be a reliable experimental animal for studies on chemical stimulation in either fresh or sea water. 2. The response of Fundulus to hydrochloric, acetic, propionic, butyric, valeric, and caproic acids was determined in fresh water, while the same acids plus sulfuric and nitric, as well as the sodium salts of the mineral acids, were tested in sea water. 3. Stimulation of Fundulus by hydrochloric acid in fresh water is correlated with the effective hydrogen ion concentration. Stimulation by the n-aliphatic acids in the same environment is correlated with two factors, the effective hydrogen ion concentration and the potential of the non-polar group in the molecule. However, as the number of CH2 groups increases the stimulating effect increases by smaller and smaller amounts, approaching a maximum value. 4. Stimulation of Fundulus by hydrochloric, sulfuric, and nitric acids in sea water is correlated with the forces of primary valence which in turn are correlated with the change in hydrogen ion concentration of the sea water. The n-aliphatic acids increase in stimulating efficiency in sea water as the length of the carbon chain increases, but a limiting value is not reached as soon as in fresh water. 5. Only a slight difference in stimulation by hydrochloric acid is found in sea water and in fresh water. However, there is a significant difference in stimulation by the fatty acids in fresh and in sea water, which is partly explained by the different buffering capacities of the two media. It is to be noted that in the same environment two different fish, Fundulus and Eupomotis, give different results, while the same fish (Fundulus) in two different environments responds similarly to mineral acids but differently to fatty acids. These results illustrate that stimulation is a function of the interaction between environment and receptors, and that each is important in determining the response. 6. Stimulation by sodium chloride, nitrate

Bottlenecks in erucic acid accumulation in genetically engineered ultrahigh erucic acid Crambe abyssinica

PubMed Central

Guan, Rui; Lager, Ida; Li, Xueyuan; Stymne, Sten; Zhu, Li-Hua

2014-01-01

Erucic acid is a valuable industrial fatty acid with many applications. The main producers of this acid are today high erucic rapeseed (Brassica napus) and mustard (Brassica juncea), which have 45%–50% of erucic acid in their seed oils. Crambe abyssinica is an alternative promising producer of this acid as it has 55%–60% of erucic acid in its oil. Through genetic modification (GM) of three genes, we have previously increased the level of erucic acid to 71% (68 mol%) in Crambe seed oil. In this study, we further investigated different aspects of oil biosynthesis in the developing GM Crambe seeds in comparison with wild-type (Wt) Crambe, rapeseed and safflower (Carthamus tinctorius). We show that Crambe seeds have very low phosphatidylcholine-diacylglycerol interconversion, suggesting it to be the main reason why erucic acid is limited in the membrane lipids during oil biosynthesis. We further show that GM Crambe seeds have slower seed development than Wt, accompanied by slower oil accumulation during the first 20 days after flowering (DAF). Despite low accumulation of erucic acid during early stages of GM seed development, nearly 86 mol% of all fatty acids accumulated between 27 and 50 DAF was erucic acid, when 40% of the total oil is laid down. Likely bottlenecks in the accumulation of erucic acid during early stages of GM Crambe seed development are discussed. PMID:24119222

Selective heterogeneous acid catalyzed esterification of N-terminal sulfyhdryl fatty acids

USDA-ARS?s Scientific Manuscript database

Our interest in thiol fatty acids lies in their antioxidative, free radical scavenging, and metal ion scavenging capabilities as applied to cosmeceutical and skin care formulations. The retail market is filled with products containing the disulfide-containing free fatty acid, lipoic acid. These pr...

[Biosynthesis of adipic acid].

PubMed

Han, Li; Chen, Wujiu; Yuan, Fei; Zhang, Yuanyuan; Wang, Qinhong; Ma, Yanhe

2013-10-01

Adipic acid is a six-carbon dicarboxylic acid, mainly for the production of polymers such as nylon, chemical fiber and engineering plastics. Its annual demand is close to 3 million tons worldwide. Currently, the industrial production of adipic acid is based on the oxidation of aromatics from non-renewable petroleum resources by chemo-catalytic processes. It is heavily polluted and unsustainable, and the possible alternative method for adipic acid production should be developed. In the past years, with the development of synthetic biology and metabolic engineering, green and clean biotechnological methods for adipic acid production attracted more attention. In this study, the research advances of adipic acid and its precursor production are reviewed, followed by addressing the perspective of the possible new pathways for adipic acid production.

Effects of aerosol formulation to amino acids and fatty acids contents in Haruan extract.

PubMed

Febriyenti; Bai-Baie, Saringat Bin; Laila, Lia

2012-01-01

Haruan (Channa striatus) extract was formulated to aerosol for wound and burn treatment. Haruan extract is containing amino acids and fatty acids that important for wound healing process. The purpose of this study is to observe the effect of formulation and other excipients in the formula to amino acids and fatty acids content in Haruan extract before and after formulated into aerosol. Precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) method is used for amino acids analysis. Fatty acids in Haruan extract were esterified using transesterification method to form FAMEs before analyzed using GC. Boron trifluoride-methanol reagent is used for transesterification. Tyrosine and methionine concentrations were different after formulated. The concentrations were decrease. There are six fatty acids have amount that significantly different after formulated into concentrate and aerosol. Contents of these fatty acids were increase. Generally, fatty acids which had content increased after formulated were the long-chain fatty acids. This might be happen because of chain extension process. Saponification and decarboxylation would give the chain extended product. Therefore contents of long-chain fatty acids were increase. Generally, the aerosol formulation did not affect the amino acids concentrations in Haruan extract while some long-chain fatty acids concentrations were increase after formulated into concentrate and aerosol.

Ethacrynic Acid

MedlinePlus

Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

Flavor Compounds in Pixian Broad-Bean Paste: Non-Volatile Organic Acids and Amino Acids.

PubMed

Lin, Hongbin; Yu, Xiaoyu; Fang, Jiaxing; Lu, Yunhao; Liu, Ping; Xing, Yage; Wang, Qin; Che, Zhenming; He, Qiang

2018-05-29

Non-volatile organic acids and amino acids are important flavor compounds in Pixian broad-bean paste, which is a traditional Chinese seasoning product. In this study, non-volatile organic acids, formed in the broad-bean paste due to the metabolism of large molecular compounds, are qualitatively and quantitatively determined by high-performance liquid chromatography (HPLC). Amino acids, mainly produced by hydrolysis of soybean proteins, were determined by the amino acid automatic analyzer. Results indicated that seven common organic acids and eighteen common amino acids were found in six Pixian broad-bean paste samples. The content of citric acid was found to be the highest in each sample, between 4.1 mg/g to 6.3 mg/g, and malic acid were between 2.1 mg/g to 3.6 mg/g ranked as the second. Moreover, fumaric acid was first detected in fermented bean pastes albeit with a low content. For amino acids, savory with lower sour taste including glutamine (Gln), glutamic acid (Glu), aspartic acid (Asp) and asparagines (Asn) were the most abundant, noted to be 6.5 mg/g, 4.0 mg/g, 6.4 mg/g, 4.9 mg/g, 6.2 mg/g and 10.2 mg/g, and bitter taste amino acids followed. More importantly, as important flavor materials in Pixian broad-bean paste, these two groups of substances are expected to be used to evaluate and represent the flavor quality of Pixian broad-bean paste. Moreover, the results revealed that citric acid, glutamic acid, methionine and proline were the most important flavor compounds. These findings are agreat contribution for evaluating the quality and further assessment of Pixian broad-bean paste.

Synthesis and characterization of boric acid mediated metal-organic frameworks based on trimesic acid and terephthalic acid

NASA Astrophysics Data System (ADS)

Ozer, Demet; Köse, Dursun A.; Şahin, Onur; Oztas, Nursen Altuntas

2017-08-01

The new metal-organic framework materials based on boric acid reported herein. Sodium and boron containing metal-organic frameworks were synthesized by one-pot self-assembly reaction in the presence of trimesic acid and terephthalic acid in water/ethanol solution. Boric acid is a relatively cheap boron source and boric acid mediated metal-organic framework prepared mild conditions compared to the other boron source based metal-organic framework. The synthesized compounds were characterized by FT-IR, p-XRD, TGA/DTA, elemental analysis, 13C-MAS NMR, 11B-NMR and single crystal measurements. The molecular formulas of compounds were estimated as C18H33B2Na5O28 and C8H24B2Na2O17 according to the structural analysis. The obtained complexes were thermally stable. Surface properties of inorganic polymer complexes were investigated by BET analyses and hydrogen storage properties of compound were also calculated.

Comparison of clinical characteristics of chronic cough due to non-acid and acid gastroesophageal reflux.

PubMed

Xu, Xianghuai; Yang, Zhongmin; Chen, Qiang; Yu, Li; Liang, Siwei; Lü, Hanjing; Qiu, Zhongmin

2015-04-01

Little is known about non-acid gastroesophageal reflux-induced chronic cough (GERC). The purpose of the study is to explore the clinical characteristics of non-acid GERC. Clinical symptoms, cough symptom score, capsaicin cough sensitivity, gastroesophageal reflux diagnostic questionnaire (GerdQ) score, findings of multichannel intraluminal impedance-pH monitoring (MII-pH) and response to pharmacological anti-reflux therapy were retrospectively reviewed in 38 patients with non-acid GERC and compared with those of 49 patients with acid GERC. Non-acid GERC had the similar cough character, cough symptom score, and capsaicin cough sensitivity to acid GERC. However, non-acid GERC had less frequent regurgitation (15.8% vs 57.1%, χ(2)  = 13.346, P = 0.000) and heartburn (7.9% vs 32.7%, χ(2)  = 7.686, P  = 0.006), and lower GerdQ score (7.4 ± 1.4 vs 10.6 ± 2.1, t = -6.700, P = 0.003) than acid GERC. Moreover, MII-pH revealed more weakly acidic reflux episodes, gas reflux episodes and a higher symptom association probability (SAP) for non-acid reflux but lower DeMeester score, acidic reflux episodes and SAP for acid reflux in non-acid GERC than in acid GERC. Non-acid GERC usually responded to the standard anti-reflux therapy but with delayed cough resolution or attenuation when compared with acid GERC. Fewer patients with non-acid GERC needed an augmented acid suppressive therapy or treatment with baclofen. There are some differences in the clinical manifestations between non-acid and acid GERC, but MII-pH is essential to diagnose non-acid GERC. © 2014 John Wiley & Sons Ltd.

[alpha]-Oxocarboxylic Acids

ERIC Educational Resources Information Center

Kerber, Robert C.; Fernando, Marian S.

2010-01-01

Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

Effects of phosphoric acid on the lead-acid battery reactions

NASA Astrophysics Data System (ADS)

Ikeda, Osamu; Iwakura, Chiaki; Yoneyama, Hiroshi; Tamura, Hideo

1986-10-01

The addition of a small amount of phosphoric acid to 5 M H2SO4 (commercial electrolyte of lead-acid batteries) results in various positive effects on the lead-acid battery reactions: (1) depression of the corrosion rate of the lead substrate through a preferential formation of alpha-PbO2 on the substrate surface; (2) retardation of hard sulfate formation or of deactivation of active materials; and (3) change in the crystal morphology of PbSO2 formed on the discharge of PbO2. Most of these effects results from chemisorption of phosphoric acid on PbSO4 crystals produced in the discharge process of PbO2.

Formation of pyroglutamic acid from N-terminal glutamic acid in immunoglobulin gamma antibodies.

PubMed

Chelius, Dirk; Jing, Kay; Lueras, Alexis; Rehder, Douglas S; Dillon, Thomas M; Vizel, Alona; Rajan, Rahul S; Li, Tiansheng; Treuheit, Michael J; Bondarenko, Pavel V

2006-04-01

The status of the N-terminus of proteins is important for amino acid sequencing by Edman degradation, protein identification by shotgun and top-down techniques, and to uncover biological functions, which may be associated with modifications. In this study, we investigated the pyroglutamic acid formation from N-terminal glutamic acid residues in recombinant monoclonal antibodies. Almost half the antibodies reported in the literature contain a glutamic acid residue at the N-terminus of the light or the heavy chain. Our reversed-phase high-performance liquid chromatography-mass spectrometry method could separate the pyroglutamic acid-containing light chains from the native light chains of reduced and alkylated recombinant monoclonal antibodies. Tryptic peptide mapping and tandem mass spectrometry of the reduced and alkylated proteins was used for the identification of the pyroglutamic acid. We identified the formation of pyroglutamic acid from N-terminal glutamic acid in the heavy chains and light chains of several antibodies, indicating that this nonenzymatic reaction does occur very commonly and can be detected after a few weeks of incubation at 37 and 45 degrees C. The rate of this reaction was measured in several aqueous buffers with different pH values, showing minimal formation of pyroglutamic acid at pH 6.2 and increased formation of pyroglutamic acid at pH 4 and pH 8. The half-life of the N-terminal glutamic acid was approximately 9 months in a pH 4.1 buffer at 45 degrees C. To our knowledge, we showed for the first time that glutamic acid residues located at the N-terminus of proteins undergo pyroglutamic acid formation in vitro.

Extractive Fermentation of Lactic Acid in Lactic Acid Bacteria Cultivation: A Review.

PubMed

Othman, Majdiah; Ariff, Arbakariya B; Rios-Solis, Leonardo; Halim, Murni

2017-01-01

Lactic acid bacteria are industrially important microorganisms recognized for their fermentative ability mostly in their probiotic benefits as well as lactic acid production for various applications. Nevertheless, lactic acid fermentation often suffers end-product inhibition which decreases the cell growth rate. The inhibition of lactic acid is due to the solubility of the undissociated lactic acid within the cytoplasmic membrane and insolubility of dissociated lactate, which causes acidification of cytoplasm and failure of proton motive forces. This phenomenon influences the transmembrane pH gradient and decreases the amount of energy available for cell growth. In general, the restriction imposed by lactic acid on its fermentation can be avoided by extractive fermentation techniques, which can also be exploited for product recovery.

Extractive Fermentation of Lactic Acid in Lactic Acid Bacteria Cultivation: A Review

PubMed Central

Othman, Majdiah; Ariff, Arbakariya B.; Rios-Solis, Leonardo; Halim, Murni

2017-01-01

Lactic acid bacteria are industrially important microorganisms recognized for their fermentative ability mostly in their probiotic benefits as well as lactic acid production for various applications. Nevertheless, lactic acid fermentation often suffers end-product inhibition which decreases the cell growth rate. The inhibition of lactic acid is due to the solubility of the undissociated lactic acid within the cytoplasmic membrane and insolubility of dissociated lactate, which causes acidification of cytoplasm and failure of proton motive forces. This phenomenon influences the transmembrane pH gradient and decreases the amount of energy available for cell growth. In general, the restriction imposed by lactic acid on its fermentation can be avoided by extractive fermentation techniques, which can also be exploited for product recovery. PMID:29209295

Cytotoxic effects of polybasic acids, poly(alkenoic acid)s, and the monomers with various functional groups on human pulp fibroblasts.

PubMed

Kurata, Shigeaki; Morishita, Kumiko; Kawase, Toshio; Umemoto, Kozo

2011-01-01

This study evaluated the cytotoxicity of various polybasic acids, poly(alkenoic acid)s, and the monomers with various acidic functional groups such as carboxyl, phosphoryl, and sulfo group. The cell growth of fibroblasts cultivated in medium containing polybasic acids and polymers up to the concentration to 5 mmol/L was not significantly different compared with that of control without their acids. On the other hand, the cell growth fibroblasts cultivated in medium containing 1 mmol/L of the monomers with acryloyloxy and phosphoryl or carboxyl group decreased remarkably compared with that of the control and the cells were probably lifeless. Those exposed to the monomers with a ether bond and a carboxyl group or a amide bond and a sulfo group was not significantly different compared with that of control.

Experiment Comparison between Engineering Acid Dew Point and Thermodynamic Acid Dew Point

NASA Astrophysics Data System (ADS)

Song, Jinghui; Yuan, Hui; Deng, Jianhua

2018-06-01

in order to realize the accurate prediction of acid dew point, a set of measurement system of acid dew point for the flue gas flue gas in the tail of the boiler was designed and built, And measured at the outlet of an air preheater of a power plant of 1 000 MW, The results show that: Under the same conditions, with the test temperature decreases, Nu of heat transfer tubes, fouling and corrosion of pipe wall and corrosion pieces gradually deepened. Then, the measured acid dew point is compared with the acid dew point obtained by using the existing empirical formula under the same coal type. The dew point of engineering acid is usually about 40 ° lower than the dew point of thermodynamic acid because of the coupling effect of fouling on the acid liquid, which can better reflect the actual operation of flue gas in engineering and has certain theoretical guidance for the design and operation of deep waste heat utilization system significance.

The use of fatty acid esters to enhance free acid sophorolipid synthesis.

PubMed

Ashby, Richard D; Solaiman, Daniel K Y; Foglia, Thomas A

2006-02-01

Fatty acid esters were prepared by transesterification of soy oil with methanol (methyl-soyate, Me-Soy), ethanol (ethyl-soyate, Et-Soy) and propanol (propyl-soyate, Pro-Soy) and used with glycerol as fermentation substrates to enhance production of free-acid sophorolipids (SLs). Fed-batch fermentations of Candida bombicola resulted in SL yields of 46 +/- 4 g/l, 42 +/- 7 g/l and 18 +/- 6 g/l from Me-Soy, Et-Soy, and Pro-Soy, respectively. Liquid chromatography with atmospheric pressure ionization mass spectrometry (LC/API-MS) showed that Me-Soy resulted in 71% open-chain SLs with 59% of those molecules remaining esterified at the carboxyl end of the fatty acids. Et-Soy and Pro-Soy resulted in 43% and 80% open-chain free-acid SLs, respectively (containing linoleic acid and oleic acid as the principal fatty acid species linked to the sophorose sugar at the omega-1 position), with no evidence of residual esterification.

Animal model of acid-reflux esophagitis: pathogenic roles of acid/pepsin, prostaglandins, and amino acids.

PubMed

Takeuchi, Koji; Nagahama, Kenji

2014-01-01

Esophagitis was induced in rats within 3 h by ligating both the pylorus and transitional region between the forestomach and glandular portion under ether anesthesia. This esophageal injury was prevented by the administration of acid suppressants and antipepsin drug and aggravated by exogenous pepsin. Damage was also aggravated by pretreatment with indomethacin and the selective COX-1 but not COX-2 inhibitor, whereas PGE2 showed a biphasic effect depending on the dose; a protection at low doses, and an aggravation at high doses, with both being mediated by EP1 receptors. Various amino acids also affected this esophagitis in different ways; L-alanine and L-glutamine had a deleterious effect, while L-arginine and glycine were highly protective, both due to yet unidentified mechanisms. It is assumed that acid/pepsin plays a major pathogenic role in this model of esophagitis; PGs derived from COX-1 are involved in mucosal defense of the esophagus; and some amino acids are protective against esophagitis. These findings also suggest a novel therapeutic approach in the treatment of esophagitis, in addition to acid suppressant therapy. The model introduced may be useful to test the protective effects of drugs on esophagitis and investigate the mucosal defense mechanism in the esophagus.

Bibliography for acid-rock drainage and selected acid-mine drainage issues related to acid-rock drainage from transportation activities

USGS Publications Warehouse

Bradley, Michael W.; Worland, Scott C.

2015-01-01

Acid-rock drainage occurs through the interaction of rainfall on pyrite-bearing formations. When pyrite (FeS2) is exposed to oxygen and water in mine workings or roadcuts, the mineral decomposes and sulfur may react to form sulfuric acid, which often results in environmental problems and potential damage to the transportation infrastructure. The accelerated oxidation of pyrite and other sulfidic minerals generates low pH water with potentially high concentrations of trace metals. Much attention has been given to contamination arising from acid mine drainage, but studies related to acid-rock drainage from road construction are relatively limited. The U.S. Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to evaluate the occurrence and processes controlling acid-rock drainage and contaminant transport from roadcuts in Tennessee. The basic components of acid-rock drainage resulting from transportation activities are described and a bibliography, organized by relevant categories (remediation, geochemical, microbial, biological impact, and secondary mineralization) is presented.

Arachidonic Acid Stress Impacts Pneumococcal Fatty Acid Homeostasis

PubMed Central

Eijkelkamp, Bart A.; Begg, Stephanie L.; Pederick, Victoria G.; Trapetti, Claudia; Gregory, Melissa K.; Whittall, Jonathan J.; Paton, James C.; McDevitt, Christopher A.

2018-01-01

Free fatty acids hold dual roles during infection, serving to modulate the host immune response while also functioning directly as antimicrobials. Of particular importance are the long chain polyunsaturated fatty acids, which are not commonly found in bacterial organisms, that have been proposed to have antibacterial roles. Arachidonic acid (AA) is a highly abundant long chain polyunsaturated fatty acid and we examined its effect upon Streptococcus pneumoniae. Here, we observed that in a murine model of S. pneumoniae infection the concentration of AA significantly increases in the blood. The impact of AA stress upon the pathogen was then assessed by a combination of biochemical, biophysical and microbiological assays. In vitro bacterial growth and intra-macrophage survival assays revealed that AA has detrimental effects on pneumococcal fitness. Subsequent analyses demonstrated that AA exerts antimicrobial activity via insertion into the pneumococcal membrane, although this did not increase the susceptibility of the bacterium to antibiotic, oxidative or metal ion stress. Transcriptomic profiling showed that AA treatment also resulted in a dramatic down-regulation of the genes involved in fatty acid biosynthesis, in addition to impacts on other metabolic processes, such as carbon-source utilization. Hence, these data reveal that AA has two distinct mechanisms of perturbing the pneumococcal membrane composition. Collectively, this work provides a molecular basis for the antimicrobial contribution of AA to combat pneumococcal infections. PMID:29867785

Pretreatment of corn stover by solid acid for d-lactic acid fermentation.

PubMed

Wang, Xiqing; Wang, Gang; Yu, Xiaoxiao; Chen, Huan; Sun, Yang; Chen, Guang

2017-09-01

Solid acid is a new acid that is safe and green, which has been widely used in the fields of acid pickling. In this study, we adopted solid acid to pretreat corn stover and used the pretreated corn stover in the fermentation of d-lactic acid. Finally, we obtained optimal conditions for the pretreatment of corn stover by solid acid: digestion temperature of 120°C, digestion time of 80min, and solid acid concentration of 1.5%. Then adding cellulase of 30FPU/g, the conversion rate of glucose reached 71.06% after enzymatic hydrolysis for 72h. In addition, the changes of corn stover structure after pretreatment were further represented by using scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). At the same time, we used the pretreated corn stover as fermentation substrate and Lactobacillus. delbrueckii sp. bulgaricus as the starting strain to produce d-lactic acid. The yield reached 18g/L, with the optical purity being 99%e.e. This research has provided a new way to comprehensively utilizae corn stover. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urinary and plasma organic acids and amino acids in chronic fatigue syndrome.

PubMed

Jones, Mark G; Cooper, Elizabeth; Amjad, Saira; Goodwin, C Stewart; Barron, Jeffrey L; Chalmers, Ronald A

2005-11-01

Previous work by others have suggested the occurrence of one or more chemical or metabolic 'markers' for ME/CFS including specific amino acids and organic acids and a number of unidentified compounds (CFSUM1, CFSUM2). We have shown elsewhere that CFSUM1 is partially derivatised pyroglutamic acid and CFSUM2 partially derivatised serine and have suggested and demonstrated that the analytical methods used were unsuitable to identify or to accurately quantify urinary metabolites. We have now made a detailed analysis of plasma and urinary amino acids and of urinary organic acids from patients with ME/CFS and from three control groups. Fasting blood plasma and timed urine samples were obtained from 31 patients with CFS, 31 age and sex-matched healthy controls, 15 patients with depression and 22 patients with rheumatoid arthritis. Plasma and urinary amino acids and urinary organic acids were determined using established and validated methods and data compared by statistical analysis. None of the previously reported abnormalities in urinary amino acids or of organic acids could be confirmed. Results however provide some evidence in patients with ME/CFS for underlying inflammatory disease and for reduced intramuscular collagen with a lowered threshold for muscle micro-injury. These factors in combination may provide a basis for the fatigue and muscle pain that are the major symptoms in these patients.

The saturated fatty acid, palmitic acid, induces anxiety-like behavior in mice.

PubMed

Moon, Morgan L; Joesting, Jennifer J; Lawson, Marcus A; Chiu, Gabriel S; Blevins, Neil A; Kwakwa, Kristin A; Freund, Gregory G

2014-09-01

Excess fat in the diet can impact neuropsychiatric functions by negatively affecting cognition, mood and anxiety. We sought to show that the free fatty acid (FFA), palmitic acid, can cause adverse biobehaviors in mice that last beyond an acute elevation in plasma FFAs. Mice were administered palmitic acid or vehicle as a single intraperitoneal (IP) injection. Biobehaviors were profiled 2 and 24 h after palmitic acid treatment. Quantification of dopamine (DA), norepinephrine (NE), serotonin (5-HT) and their major metabolites was performed in cortex, hippocampus and amygdala. FFA concentration was determined in plasma. Relative fold change in mRNA expression of unfolded protein response (UPR)-associated genes was determined in brain regions. In a dose-dependent fashion, palmitic acid rapidly reduced mouse locomotor activity by a mechanism that did not rely on TLR4, MyD88, IL-1, IL-6 or TNFα but was dependent on fatty acid chain length. Twenty-four hours after palmitic acid administration mice exhibited anxiety-like behavior without impairment in locomotion, food intake, depressive-like behavior or spatial memory. Additionally, the serotonin metabolite 5-HIAA was increased by 33% in the amygdala 24h after palmitic acid treatment. Palmitic acid induces anxiety-like behavior in mice while increasing amygdala-based serotonin metabolism. These effects occur at a time point when plasma FFA levels are no longer elevated. Copyright © 2014 Elsevier Inc. All rights reserved.

UNSATURATED AMINO ACIDS V.

PubMed Central

Shapira, Jacob; Dittmer, Karl

1961-01-01

Shapira, Jacob (Department of Chemistry, Florida State University, Tallahassee) and Karl Dittmer. Unsaturated amino acids. V. Microbiological properties of some halogenated olefinic amino acids. J. Bacteriol. 82:640–647. 1961.—It has been shown previously that several amino acid analogues containing unsaturated linkages were inhibitors of the growth of Escherichia coli and Saccharomyces cerevisiae. This paper reports the results obtained when a series of unsaturated halogen-containing amino acids was examined. The cis isomer of ω-chloroallylglycine showed the greatest toxicity yet found in this series of unsaturated amino acids toward E. coli, whereas the trans-isomer was usually far less toxic. The major effect of cis-ω-chloroallylglycine in E. coli appeared to be to extend the lag phase before the normal rate of growth began. A wide variety of amino acids was capable of partially or completely preventing the toxicity of low levels of these compounds. At higher levels, relatively few amino acids (primarily valine, leucine, and glutamic acid) were effective. In E. coli, cis-ω-chloroallylglycine showed an unusual [Formula: see text] relationship with both glutamic acid and valine over a wide range in concentration. PMID:13911278

Industrial production of L-ascorbic Acid (vitamin C) and D-isoascorbic acid.

PubMed

Pappenberger, Günter; Hohmann, Hans-Peter

2014-01-01

L-ascorbic acid (vitamin C) was first isolated in 1928 and subsequently identified as the long-sought antiscorbutic factor. Industrially produced L-ascorbic acid is widely used in the feed, food, and pharmaceutical sector as nutritional supplement and preservative, making use of its antioxidative properties. Until recently, the Reichstein-Grüssner process, designed in 1933, was the main industrial route. Here, D-sorbitol is converted to L-ascorbic acid via 2-keto-L-gulonic acid (2KGA) as key intermediate, using a bio-oxidation with Gluconobacter oxydans and several chemical steps. Today, industrial production processes use additional bio-oxidation steps with Ketogulonicigenium vulgare as biocatalyst to convert D-sorbitol to the intermediate 2KGA without chemical steps. The enzymes involved are characterized by a broad substrate range, but remarkable regiospecificity. This puzzling specificity pattern can be understood from the preferences of these enyzmes for certain of the many isomeric structures which the carbohydrate substrates adopt in aqueous solution. Recently, novel enzymes were identified that generate L-ascorbic acid directly via oxidation of L-sorbosone, an intermediate of the bio-oxidation of D-sorbitol to 2KGA. This opens the possibility for a direct route from D-sorbitol to L-ascorbic acid, obviating the need for chemical rearrangement of 2KGA. Similar concepts for industrial processes apply for the production of D-isoascorbic acid, the C5 epimer of L-ascorbic acid. D-isoascorbic acid has the same conformation at C5 as D-glucose and can be derived more directly than L-ascorbic acid from this common carbohydrate feed stock.

Differential effects of eicosapentaenoic acid and docosahexaenoic acid on human skin fibroblasts.

PubMed

Brown, E R; Subbaiah, P V

1994-12-01

To better understand the mode of action of omega 3 fatty acids in cell membranes, human foreskin fibroblasts were grown in serum-free medium supplemented with 50 microM oleic acid linoleic acid, eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), and the effects on membrane composition, fluorescence polarization and enzyme activities were followed. The cells were enriched with EPA and DHA up to 7 and 13% of total lipids, respectively, of which > 95% was associated with phospholipids. In addition, the concentration of 22:5n-3 increased with both EPA and DHA to 7.5, and 2.1% of the total fatty acids, respectively. When compared to controls (oleic acid), cells treated with DHA showed a decrease in cholesterol, phospholipids, arachidonic acid (AA) and free cholesterol/phospholipid ratio (P < 0.05). In the presence of EPA, only decreases in AA and cholesterol were significant (P < 0.05). Membrane fluidity, assessed by fluorescence anisotropy, was increased 16% in cells enriched with DHA (P < 0.05), but showed no change with EPA or linoleic acid. There was an increase in membrane-associated 5'-nucleotidase (+27%) and adenylate cyclase (+19%) activities (P < 0.05), in DHA-enriched, but not in EPA-enriched cells, when compared with oleate controls. The studies show that incorporation of DHA, but not EPA, into cell membranes of fibroblasts alters membrane biophysical characteristics and function. We suggest that these two major n-3 fatty acids of fish oils have differential effects on cell membranes, and this may be related to the known differences in their physiological effects.

Effects of alkali or acid treatment on the isomerization of amino acids.

PubMed

Ohmori, Taketo; Mutaguchi, Yuta; Doi, Katsumi; Ohshima, Toshihisa

2012-10-01

The effect of alkali treatment on the isomerization of amino acids was investigated. The 100×D/(D+L) values of amino acids from peptide increased with increase in the number of constituent amino acid residues. Furthermore, the N-terminal amino acid of a dipeptide was isomerized to a greater extent than the C-terminal residue. Copyright © 2012. Published by Elsevier B.V.

Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells.

PubMed

Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J

2017-09-01

Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.

Synthesis of novel lipoamino acid conjugates of sapienic acid and evaluation of their cytotoxicity activities.

PubMed

Gopal, Sanganamoni Chinna; Kaki, Shiva Shanker; Rao, Bhamidipati V S K; Poornachandra, Yedla; Kumar, Chityal Ganesh; Narayana Prasad, Rachapudi Badari

2014-01-01

Novel lipoamino acids were prepared with the coupling of sapienic acid [(Z)-6-hexadecenoic acid] with α - amino group of amino acids and the resulting N-sapienoyl amino acids were tested for their cytotoxicity activities against four cancer based cell lines. Initially, sapienic acid was synthesized by the Wittig coupling of triphenylphosphonium bromide salt of 6-bromohexanoic acid and decanal with a Z specific reagent. The prepared sapienic acid was subsequently converted to its acid chloride which was further coupled with amino acids by the Schotten-Baumann reaction to form N-sapienoyl amino acid conjugates. Structural characterization of the prepared N-sapienoyl amino acid derivatives was done by spectral data (IR, mass spectra and NMR). These lipoamino acid derivatives were screened for in vitro cytotoxicity evaluation. Cytotoxicity evaluation against four cancer cell lines showed that N-sapienoyl isoleucine was active against three cell lines whereas other derivatives either showed activity against only one or two cell lines with very moderate activity and two derivatives were observed to be inactive against the tested cell lines.

Strong-acid, carboxyl-group structures in fulvic acid from the Suwannee River, Georgia. 1. Minor structures

USGS Publications Warehouse

Leenheer, J.A.; Wershaw, R. L.; Reddy, M.M.

1995-01-01

An investigation of the strong-acid characteristics (pKa 3.0 or less) of fulvic acid from the Suwannee River, Georgia, was conducted. Quantitative determinations were made for amino acid and sulfur-containing acid structures, oxalate half-ester structures, malonic acid structures, keto acid structures, and aromatic carboxyl-group structures. These determinations were made by using a variety of spectrometric (13C-nuclear magnetic resonance, infrared, and ultraviolet spectrometry) and titrimetric characterizations on fulvic acid or fulvic acid samples that were chemically derivatized to indicate certain functional groups. Only keto acid and aromatic carboxyl-group structures contributed significantly to the strong-acid characteristics of the fulvic acid; these structures accounted for 43% of the strong-acid acidity. The remaining 57% of the strong acids are aliphatic carboxyl groups in unusual and/or complex configurations for which limited model compound data are available.

Sulfuric Acid on Europa

NASA Image and Video Library

1999-09-30

Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain. This image is based on data gathered by Galileo's near infrared mapping spectrometer. Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks. http://photojournal.jpl.nasa.gov/catalog/PIA02500

Solubility limits of dibutyl phosphoric acid in uranium-nitric acid solutions

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

Pierce, R.A.

2000-01-04

The Savannah River Site has enriched uranium (EU) solution that has been stored since being purified in its solvent extraction processes. The concentrations in solution are approximately 6 g/L U and 0.1 M nitric acid. Residual tributylphosphate in solution has slowly hydrolyzed to form dibutyl phosphoric acid (HDBP) at concentrations averaging 30--50 mg/L. Dibutyl phosphoric acid, in turn, is in equilibrium with (HDBP){sub 2} and DBP{sup {minus}}. Uranium can form compounds with the dibutylphosphate ion (DBP{sup {minus}}) which have limited solubility, thereby creating a nuclear criticality safety issue. Literature reports and earlier SRTC tests have shown that it is feasiblemore » to precipitate U-DBP solid during the storage and processing of EU solutions. As a result, a series of solubility experiments were run at nitric acid concentrations from 0--4.0 M HNO{sub 3}, uranium at 0--90 g/L, and temperatures from 0--30 C. The data shows temperature and nitric acid concentration dependence consistent with what would be expected. With respect to uranium concentration, U-DBP solubility passes through a minimum between 6 and 12 g/L U at the acid concentrations and temperatures studied. However, the minimum shows a slight shift toward lower uranium concentrations at lower nitric acid concentrations. The shifts in solubility are strongly dependent upon the overall ionic strength of the solution. The data also reveal a shift to higher DBP solubility above 0.5 M HNO{sub 3} for both 6 g/L and 12 g/L uranium solutions. Analysis of U-DBP solids from the tests identified distinct differences between precipitates from less than 0.5 M solutions and those from greater than 4 M acid. Analyses identified UO{sub 2}(DBP){sub 2} as the dominant compound present at low acid concentrations in accordance with literature reports. As the acid concentration increases, the crystalline UO{sub 2}(DBP){sub 2} shows molecular substitutions and an increase in amorphous content.« less

Method for production of petroselinic acid and OMEGA12 hexadecanoic acid in transgenic plants

DOEpatents

Ohlrogge, John B.; Cahoon, Edgar B.; Shanklin, John; Somerville, Christopher R.

1995-01-01

The present invention relates to a process for producing lipids containing the fatty acid petroselinic acid in plants. The production of petroselinic acid is accomplished by genetically transforming plants which do not normally accumulate petroselinic acid with a gene for a .omega.12 desaturase from another species which does normally accumulate petroselinic acid.

Effect of omega-3 fatty acids on the modification of erythrocyte membrane fatty acid content including oleic acid in peritoneal dialysis patients.

PubMed

An, W S; Lee, S M; Son, Y K; Kim, S E; Kim, K H; Han, J Y; Bae, H R; Park, Y

2012-01-01

Erythrocyte membrane fatty acids (FA), such as oleic acid, are related to acute coronary syndrome. There is no report about the effect of omega-3 FA on oleic acid in peritoneal dialysis (PD) patients. We hypothesized that omega-3 FA can modify erythrocyte membrane FA, including oleic acid, in PD patients. In a double-blind, randomized, placebo-controlled study, 18 patients who were treated with PD for at least 6 months were randomized to treatment for 12 weeks with omega-3 FA or placebo. Erythrocyte membrane FA content was measured by gas chromatography at baseline and after 12 weeks. The erythrocyte membrane content of eicosapentaenoic acid and docosahexaenoic acid was significantly increased and saturated FA and oleic acid were significantly decreased in the omega-3 FA supplementation group after 12 weeks compared to baseline. In conclusion, erythrocyte membrane FA content, including oleic acid, was significantly modified by omega-3 FA supplementation for 12 weeks in PD patients. Copyright © 2011 Elsevier Ltd. All rights reserved.

Discovery of essential fatty acids

PubMed Central

Spector, Arthur A.; Kim, Hee-Yong

2015-01-01

Dietary fat was recognized as a good source of energy and fat-soluble vitamins by the first part of the 20th century, but fatty acids were not considered to be essential nutrients because they could be synthesized from dietary carbohydrate. This well-established view was challenged in 1929 by George and Mildred Burr who reported that dietary fatty acid was required to prevent a deficiency disease that occurred in rats fed a fat-free diet. They concluded that fatty acids were essential nutrients and showed that linoleic acid prevented the disease and is an essential fatty acid. The Burrs surmised that other unsaturated fatty acids were essential and subsequently demonstrated that linolenic acid, the omega-3 fatty acid analog of linoleic acid, is also an essential fatty acid. The discovery of essential fatty acids was a paradigm-changing finding, and it is now considered to be one of the landmark discoveries in lipid research. PMID:25339684

Automated protein hydrolysis delivering sample to a solid acid catalyst for amino acid analysis.

PubMed

Masuda, Akiko; Dohmae, Naoshi

2010-11-01

In this study, we developed an automatic protein hydrolysis system using strong cation-exchange resins as solid acid catalysts. Examining several kinds of inorganic solid acids and cation-exchange resins, we found that a few cation-exchange resins worked as acid catalysts for protein hydrolysis when heated in the presence of water. The most efficient resin yielded amounts of amino acids that were over 70% of those recovered after conventional hydrolysis with hydrochloric acid and resulted in amino acid compositions matching the theoretical values. The solid-acid hydrolysis was automated by packing the resin into columns, combining the columns with a high-performance liquid chromatography system, and heating them. The amino acids that constitute a protein can thereby be determined, minimizing contamination from the environment.

Racemic resolution of some DL-amino acids using Aspergillus fumigatus L-amino acid oxidase.

PubMed

Singh, Susmita; Gogoi, Binod K; Bezbaruah, Rajib L

2011-07-01

The ability of Aspergillus fumigatus L-amino acid oxidase (L-aao) to cause the resolution of racemic mixtures of DL-amino acids was investigated with DL-alanine, DL-phenylalanine, DL-tyrosine, and DL-aspartic acid. A chiral column, Crownpak CR+ was used for the analysis of the amino acids. The enzyme was able to cause the resolution of the three DL-amino acids resulting in the production of optically pure D-alanine (100% resolution), D-phenylalanine (80.2%), and D-tyrosine (84.1%), respectively. The optically pure D-amino acids have many uses and thus can be exploited industrially. This is the first report of the use of A. fumigatus L: -amino acid oxidase for racemic resolution of DL-amino acids.

Blood-brain barrier transport of the alpha-keto acid analogs of amino acids.

PubMed

Steele, R D

1986-06-01

A number of alpha-keto acid analogs of amino acids have been found to penetrate the blood-brain barrier (BBB). Pyruvate, alpha-ketobutyrate, alpha-ketoisocaproate, and alpha-keto-gamma-methiolbutyrate all cross the BBB by a carrier-mediated process and by simple diffusion. Under normal physiological conditions, diffusion accounts for roughly 15% or less of total transport. Aromatic alpha-keto acids, phenylpyruvate, and p-hydroxyphenylpyruvate do not penetrate the BBB, nor do they inhibit the transport of other alpha-keto acids. Evidence based primarily on inhibition studies indicates that the carrier-mediated transport of alpha-keto acids occurs via the same carrier demonstrated previously for propionate, acetoacetate, and beta-hydroxybutyrate transport, commonly referred to as the monocarboxylate carrier. As a group, the alpha-keto acid analogs of the amino acids have the highest affinity for the carrier, followed by propionate and beta-hydroxybutyrate. Starvation for 4 days induces transport of alpha-keto acids, but transport is suppressed in rats fed commercial laboratory rations and subjected to portacaval shunts. The mitochondrial pyruvate translocator inhibitor alpha-cyanocinnamate has no effect on the BBB transport of alpha-keto acids.