Analysis of Polyphenols in Apple Pomace using Gas Chromatography-Mass Spectrometry with Derivatization

Phenolic contents, anticancer, antioxidant, and antimicrobial capacities of MeOH extract from the aerial parts of Trema orientalis plant

Medicinal plants contain phytochemical components of pharmaceutical importance, and Trema orientalis MeOH extracts are believed to have potential antioxidant and cytotoxic properties. This investigation explores the phenolic, antioxidant, and anticancer property of the methanol extracts of aerial parts of T. orientalis. The total polyphenol content (TPC) and the total flavonoid contents (TFC) were determined following standard methods. In vitro antioxidant property was assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Cytotoxicity experiments were performed against eight cell lines and one fibroblast cell using the methylthiazolyldiphenyl-tetrazolium bromide assay. The antimicrobial activity assay was performed using the agar-diffusion method. Individual phenolic acids identified by GC/MS were examined in silico to estimate their drug likeness based on their structures. TPC and TFC were the highest in the leaf extract, with the strongest radical scavenging activity against ABTS (84.43%) and DPPH (79.60%) radicals. The highest cytotoxicity activity was exhibited by leaf (IC50 = 2.256 ± 0.85 μg/mL) and twig (2.704 ± 1.31 μg/mL) extracts against the HCT116 cell line, followed by bark (3.653 ± 0.05 μg/mL) and leaf (3.725 ± 0.30 μg/mL) extracts against the HT29 cell line. Clonogenicity resulted in a clear decrease of colony formation by HCT116 cells, suggesting a dose-dependent mode. In silico investigation suggested that phenolic acids detected have non-drug-like properties. Extracts showed antimicrobial inactivity.

Edible plant by-products as source of polyphenols: prebiotic effect and analytical methods

Polyphenols with high chemical diversity are present in vegetables both in the edible parts and by-products. A large proportion of them remains unabsorbed along the gastrointestinal tract, being accumulated in the colon, where they are metabolized by the intestinal microbiota. These polyphenols have been found to have "prebiotic-like" effects. The edible plant industry generates tons of residues called by-products, which consist of unutilized plant tissues (peels, husks, calyxes and seeds). Their disposal requires special and costly treatments to avoid environmental complications. Reintroducing these by-products into the value chain using technological and biotechnological practices is highly appealing since many of them contain nutrients and bioactive compounds, such as polyphenols, with many health-promoting properties. Edible plant by-products as a source of polyphenols highlights the need for analytical methods. Analytical methods are becoming increasingly selective, sensitive and precise, but the great breakthrough lies in the pretreatment of the sample and in particular in the extraction methods. This review shows the importance of edible plant by-products as a source of polyphenols, due to their prebiotic effect, and to compile the most appropriate analytical methods for the determination of the total content of phenolic compounds as well as the detection and quantification of individual polyphenols.

Microalgae as Sustainable Biofactories to Produce High-Value Lipids: Biodiversity, Exploitation, and Biotechnological Applications

Microalgae are often called “sustainable biofactories” due to their dual potential to mitigate atmospheric carbon dioxide and produce a great diversity of high-value compounds. Nevertheless, the successful exploitation of microalgae as biofactories for industrial scale is dependent on choosing the right microalga and optimum growth conditions. Due to the rich biodiversity of microalgae, a screening pipeline should be developed to perform microalgal strain selection exploring their growth, robustness, and metabolite production. Current prospects in microalgal biotechnology are turning their focus to high-value lipids for pharmaceutic, nutraceutic, and cosmetic products. Within microalgal lipid fraction, polyunsaturated fatty acids and carotenoids are broadly recognized for their vital functions in human organisms. Microalgal-derived phytosterols are still an underexploited lipid resource despite presenting promising biological activities, including neuroprotective, anti-inflammatory, anti-cancer, neuromodulatory, immunomodulatory, and apoptosis inductive effects. To modulate microalgal biochemical composition, according to the intended field of application, it is important to know the contribution of each cultivation factor, or their combined effects, for the wanted product accumulation. Microalgae have a vital role to play in future low-carbon economy. Since microalgal biodiesel is still costly, it is desirable to explore the potential of oleaginous species for its high-value lipids which present great global market prospects.

In vitro antioxidant study of polyphenol from red seaweeds dichotomously branched gracilaria Gracilaria edulis and robust sea moss Hypnea valentiae

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Screen the polyphenol compound from red seaweed Gracilaria edulis and Hypnea valentiae.

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Purification the polyphenol compound.

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Detect the antimicrobial activity of polyphenol compound.

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Evaluate the antioxidant activity of polyphenol compound.

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Analyze the FT-IR and GC MS of polyphenol compound.

In recent years, seaweeds drew the intense attention of the researchers owing their biological properties with their multi assorted applications to the humans. Red seaweeds are well-known for their biological activities due to enrichment of phenolic residues. The present investigation deals with the portrayal of biological behavior of red algae Gracilaria edulis and Hypnea valentiae. Polyphenol was extracted using methanol in a soxhlet extractor for 6 h. The crude polyphenol compound was partially purified in DEAE cellulose52 column. The total phenolic content present in the polyphenol compound was G. edulis (75.49 ± 0.12 %) and H. valentiae (70.08 ± 0.34 %). The phytochemicals present in the two seaweeds were flavonoids, saponins, tannins, phenolics, alkaloids and steroids. The antimicrobial activity of polyphenol compounds was assessed against seven human pathogens, five plant pathogens and three fungal pathogens. The free radical scavenging activity of polyphenol compound was assayed such as total antioxidant capacity, reducing power, hydrogen peroxide scavenging activity, DPPH, ABTS, hydroxyl-scavenging assay, superoxide anion radical scavenging and nitric oxide. Polyphenol compound was analyzed by FT-IR and GC–MS.

Nutritional and Health-Related Effects of a Diet Containing Apple Seed Meal in Rats: The Case of Amygdalin

Apple pomace includes seeds that are rich in protein, fiber, and oil, which can be extracted from them. However, they can also contain a significant amount of toxigenic amygdalin. We hypothesized that amygdalin is a compound that significantly reduces the nutritional and health quality of defatted apple seeds. An experiment was conducted on rats that were distributed into three groups and fed with high-fructose diets. In the control (C) and amygdalin (AMG) groups, cellulose and casein were the source of dietary fiber and protein, respectively; in the apple seed meal (ASM) group, dietary fiber and protein originated from the endosperm of apple seeds, which were previously defatted and ground. A diet fed to the ASM group also contained 0.24% of amygdalin from the meal, whereas the AMG diet was supplemented with the same amount of synthetic amygdalin. After 14 days of experimental feeding, the body weight of rats was decreased in the ASM group. When compared to the C group, apparent protein digestibility and nitrogen retention were increased in the AMG group, while both were decreased in the ASM group. In the small intestine, mucosal maltase activity was decreased in the AMG and ASM groups, whereas lactase activity was only decreased by dietary amygdalin. The caecal SCFA pool and butyrate concentration were significantly increased in the ASM group compared to the other groups. Moreover, the ASM diet increased plasma concentration of high density lipoprotein (HDL) cholesterol and plasma antioxidant capacity of water-soluble substances (ACW). It also decreased the liver content of thiobarbituric acid-reactive substances (TBARS). In contrast, dietary amygdalin did not affect these indices. Dietary supplementation with apple seed meal can exert beneficial effects on the intestinal tract, blood lipid profile and antioxidant status of rats. In most cases, these effects are not limited by the presence of amygdalin. However, the nutritional value of protein from apple seed meal is relatively low.

Injection-port derivatization coupled to GC-MS/MS for the analysis of glycosylated and non-glycosylated polyphenols in fruit samples

Polyphenols, including glycosylated polyphenols, were analyzed via a procedure based on injection-port derivatization coupled to gas chromatography-tandem mass spectrometry (GC-MS/MS). The polyphenols in lyophilized fruit samples were extracted with an acidified MeOH mixture assisted by ultrasound. Samples were dried under vacuum, and carbonyl groups were protected with methoxylamine. Free hydroxyl groups were subsequently silylated in-port. Mass fragmentations of 17 polyphenol and glycosylated polyphenol standards were examined using Multiple Reaction Monitoring (MRM) as the acquisition mode. Furthermore, in-port derivatization was optimized in terms of optimal injection port temperature, derivatization time and sample: N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) volume ratio. A C18 solid-phase-extraction clean-up method was used to reduce matrix effects and injection liner degradation. Using this clean-up method, recoveries for samples spiked at 1 and 10μg/g ranged from 52% to 98%, depending on the chemical compound. Finally, the method was applied to real fruit samples containing the target compounds. The complete chromatographic runtime was 15min, which is faster than reported for recent HPLC methods able to analyze similar compounds.