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

Analysis of Three Species of Cassipourea Traditionally Used for Hypermelanosis in Selected Provinces in South Africa

There is a growing demand and use of herbal cosmetics for skin purposes due to their perceived safety when applied to the skin. Three Cassipourea species commonly known as "ummemezi" are used interchangeably by women in rural areas of Eastern Cape and KwaZulu-Natal provinces to treat hypermelanosis as well as sun protection. We conducted a phytochemical comparison of three Cassipourea species; Cassipourea flanaganii (Schinz) Alston, Cassipourea gummiflua Tul. verticillata (N.E.Br.) J. Lewis and Cassipourea malosana (Baker) Alston by Liquid Chromatography-Mass Spectrometry (LC-MS/MS) analysis in negative mode. The results obtained from the LC-MS/MS yielded a total number of twenty-four compounds of different chemical classes, including fatty acids, steroids, di- and tri-terpenoids, flavonoids, phenolic acids, and eighteen among them were tentatively identified. The LC-MS /MS analysis showed that the three studied Cassipourea extracts contain compounds that have anti-tyrosinase activity and consequently. The presence of these compounds, either in synergy or individually, can be attributed to the anti-tyrosinase effect. Although the traditional names of the species are used interchangeably, they are different, however, they possess similar skin-lightening properties. Despite the recent popularity of modern cosmetic products, plants continue to play an important role in the local cosmetics industry in South Africa's Eastern Cape and KwaZulu-Natal community provinces.

An Investigation into the Acute and Subacute Toxicity of Extracts of Cassipourea flanaganii Stem Bark In Vivo

The conventional use of medicinal plants is in part based on the widespread belief that plant crude extracts are non-toxic. In South Africa, traditional preparations of Cassipourea flanaganii used to treat hypermelanosis have accordingly been regarded by many as non-toxic. Whether that is so impacts on the potential of bark extracts to be developed as a commercial drug to treathypermelanosis, given their documented capacity to inhibit tyrosinase activity. Our study investigated the acute and subacute toxicity of the methanol extract of C. flanaganii bark in rats. Wistar rats were randomly assigned into different treatment groups. The rats received a daily oral gavage of crude extract for acute and subacute toxicity tests. Haematological, biomechanical, clinical and histopathology examinations were carried out to evaluate the possible toxicity of C. flanaganii. The results were subjected to the Student's t-test and ANOVA. For both acute and subacute toxicity, there was no statistical difference between the groups. There were no clinical or behavioral signs of toxicity observed in the rats. No treatment-related gross pathology lesions and no histopathology were observed. The findings of this study demonstrate the absence of acute or subacute toxicity after oral treatment with C. flanaganii stem bark extracts in Wistar rats at the levels administered. Chemical profiling of the total extract using LC-MS tentatively identified eleven (11) compounds as the major chemical constituents.

How Does Lagenaria siceraria (Bottle Gourd) Metabolome Compare to Cucumis sativus (Cucumber) F. Cucurbitaceae? A Multiplex Approach of HR-UPLC/MS/MS and GC/MS Using Molecular Networking and Chemometrics

Cucurbitaceae comprises 800 species, the majority of which are known for their nutritive, economic, and health-promoting effects. This study aims at the metabolome profiling of cucumber (Cucumis sativus) and bottle gourd (Lagenaria siceraria) fruits in a comparative manner for the first time, considering that both species are reported to exhibit several in-common phytochemical classes and bioactivities. Nevertheless, bottle gourd is far less known and/or consumed than cucumber, which is famous worldwide. A multiplex approach, including HR-UPLC/MS/MS, GNPS networking, SPME, and GC/MS, was employed to profile primary and secondary metabolites in both species that could mediate for new health and nutritive aspects, in addition to their aroma profiling, which affects the consumers' preferences. Spectroscopic datasets were analyzed using multivariate data analyses (PCA and OPLS) for assigning biomarkers that distinguish each fruit. Herein, 107 metabolites were annotated in cucumber and bottle gourd fruits via HR-UPLC/MS/MS analysis in both modes, aided by GNPS networking. Metabolites belong to amino acids, organic acids, cinnamates, alkaloids, flavonoids, pterocarpans, alkyl glycosides, sesquiterpenes, saponins, lignans, fatty acids/amides, and lysophospholipids, including several first-time reported metabolites and classes in Cucurbitaceae. Aroma profiling detected 93 volatiles presented at comparable levels in both species, from which it can be inferred that bottle gourds possess a consumer-pleasant aroma, although data analyses detected further enrichment of bottle gourd with ketones and esters versus aldehydes in cucumber. GC/MS analysis of silylated compounds detected 49 peaks in both species, including alcohols, amino acids, fatty acids/esters, nitrogenous compounds, organic acids, phenolic acids, steroids, and sugars, from which data analyses recognized that the bottle gourd was further enriched with fatty acids in contrast to higher sugar levels in cucumber. This study provides new possible attributes for both species in nutrition and health-care fields based on the newly detected metabolites, and further highlights the potential of the less famous fruit "bottle gourd", recommending its propagation.

An innovative spectrofluorimetric approach for determination of azelaic acid in bulk and pharmaceutical formulation through derivatization with 9-chloromethylanthracene

A novel simple, selective and accurate spectrofluorimetric method has been developed for quantitation of azelaic acid (AZA) in bulk and cream dosage form. The proposed method depended on the reaction between dicarboxylic moiety of AZA and 9-chloromethylanthracence to produce fluorescent derivative that exhibited maximum fluorescence intensity at 413 nm after being excited at 365 nm. The numerous experimental parameters which affect the reaction product and stability have been carefully studied and optimized. The linearity of the calibration curve constructed has been 0.5-15 µg/ml (y = 26.864x + 31.793, r² = 0.9999) with 0.143 and 0.434 µg/ml as LOD and LOQ values respectively. The method was used for quantitation of AZA in cream dosage form and the results showed that there was no interference from the cream excipients, the mean % recovery was 100.547% ± 0.775.

Optimization of Experimental Procedure for Determining Azelaic Acid in Cosmetics by Gas Chromatography Derivatized through Ethanol

The quantitative evaluation of azelaic acid is becoming critical in the development of new medicinal products and in environment. A feasible method for the determination of azelaic acid in cosmetics by gas chromatographic-mass spectrometer detector (GC-MS) with derivation was developed and optimized. The derivative effect was good, when azelaic acid was derivatized through ethanol at room temperature for 10 min with 800 μL of sulfuric acid as a catalyst. A good linear relationship of azelaic acid derivative was present from 10 to 1000 mg L^-1 (R ² = 0.9997). Detection limit and quantitative limit of GC was 15 and 50 mg kg^-1, respectively. The recovery rate was in the range from 87.7% to 101% with all relative standard deviation (RSD) values less than 4%, denoting the method meeting the requirement of the analysis. Therefore, this method has the advantages of strong anti-interference ability and accurate results. Among the eight samples nominally azelaic acid, only three were detected. The respective content was 78 133, 16 710, and 2431 mg kg^-1. The results showed that the actual addition of the azelaic acid in the market was quite different with label identification, being worthy of further attention. Further, it also provided a favorable experience for the monitoring of azelaic acid in the environment.

Corryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae): Antioxidant, Gastroprotective Effects, and Metabolomic Profiling by Ultrahigh-Pressure Liquid Chromatography and Electrospray High Resolution Orbitrap Tandem Mass Spectrometry

Corryocactus brevistylus (K. Schum. ex Vaupel) Britton & Rose (Cactaceae) is a shrubby or often arborescent cactus popularly known as "sancayo" and produce an edible fruit known as "Sanky" which is consumed in Arequipa-Perú. The purpose of this study was to report the gastroprotective activity and relate this activity to the antioxidant capacity and presence of phenolic compounds for the first time. A metabolomic profiling based on Ultrahigh-pressure liquid chromatography and electrospray high resolution mass spectrometry, and the antioxidant activities (DPPH, ABTS, and FRAP), ascorbic acid content, total phenolics and flavonoids contents, and the mode of gastroprotective action of the Sanky fruit including the involvement of prostaglandins, nitric oxide, and sulfhydryl compounds is reported. Thirty-eight compounds were detected in the ethanolic extract including 12 organic acids, nine hydroxycinnamic acids, three isoamericanol derivatives, six flavonoids, five fatty acids, and two sterols. The results of the biological tests showed that the ethanolic extract had antioxidant capacity and gastroprotective activity on the model of HCl/EtOH-induced gastric lesions in mice (at 10, 25, 50, and 100 mg/kg). The effect elicited by the extract at 50 mg/kg was reversed by indometacin and N-ethylmaleimide but not by N^G-nitro-L-arginine methyl ester suggesting that sulfhydryl groups and prostaglandins are involved in the mode of gastroprotective action. In conclusion, our study proves that C. brevistylus pears have some gastroprotective and antioxidant capacities and consumption is recommended for the presence of several bioactive compounds.

Anti-atherosclerotic and anti-inflammatory actions of sesame oil

Atherosclerosis, a major form of cardiovascular disease, has now been recognized as a chronic inflammatory disease. Nonpharmacological means of treating chronic diseases have gained attention recently. We previously reported that sesame oil has anti-atherosclerotic properties. In this study, we have determined the mechanisms by which sesame oil might modulate atherosclerosis by identifying genes and inflammatory markers. Low-density lipoprotein receptor knockout (LDLR(-/-)) female mice were fed with either an atherogenic diet or an atherogenic diet reformulated with sesame oil (sesame oil diet). Plasma lipids and atherosclerotic lesions were quantified after 3 months of feeding. Plasma samples were used for cytokine analysis. RNA was extracted from the liver tissue and used for global gene arrays. The sesame oil diet significantly reduced atherosclerotic lesions, plasma cholesterol, triglyceride, and LDL cholesterol levels in LDLR(-/-) mice. Plasma inflammatory cytokines, such as MCP-1, RANTES, IL-1α, IL-6, and CXCL-16, were significantly reduced, demonstrating an anti-inflammatory property of sesame oil. Gene array analysis showed that sesame oil induced many genes, including ABCA1, ABCA2, APOE, LCAT, and CYP7A1, which are involved in cholesterol metabolism and reverse cholesterol transport. In conclusion, our studies suggest that a sesame oil-enriched diet could be an effective nonpharmacological treatment for atherosclerosis by controlling inflammation and regulating lipid metabolism.

Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants

Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.