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Apr 2023 DOI 10.14302/issn.2471-2140.jaa-22-4251
Kumari SachinCorresponding author
The study's goal was to determine the total phenolics, total flavonoids, and antioxidant activity of A. mexicana aerial parts. Extracts were prepared using different solvents namely n-hexane, ethyl acetate, acetone, methanol, and water on basis of increasing polarity using soxhlet appratus. Aqueous extract from the flower contained the highest level of total phenolics, followed by that of the stem and leaves. The flower methanol extract was found to contain the most total flavonoids. With IC50 values of 24.98 g/ml in acetone extract, the stem component demonstrated the most DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging activity, followed by leaves with IC50 values of 36.29 g/ml in hexane extract and flowers with IC50 values of 38.33 g/ml in acetone extract. FTIR analysis showed that the presence of phenols and flavanoids. In different solvents, the DPPH free radical scavenging activity of aerial portions of A. mexicana varied greatly, and it increased with increasing concentration levels. In terms of antioxidant potency, higher amounts of total phenolics in aqueous extract, total flavonoids in methanol extract, and acetone extract were shown to be the most potent antioxidant. The aerial parts of A. mexicana have a considerable amount of flavanoids, phenolics, and antioxidant activity.
Dec 2021 DOI 10.14302/issn.2471-2140.jaa-21-4027
Singh SushilaCorresponding author
Department of Chemistry, CCS Haryana Agricultural University, Hisar, Haryana, India.
Medicinal plants have been used since the era of Vedic history for their health care system where herbal medicine has a long history of use. It is also a very popular medicinal plant belonging to the Leguminosae family and is commonly known as Mulhatti. It contains phytochemicals such as flavonoids, triterpene saponins and other constituents such as coumarins, sugars, amino acids, tannins, starch, choline, phytosterols etc. The present study was conducted for the estimation of phytochemicals (total phenols and flavonoids) and the evaluation of the total antioxidant capacity and DPPH free-radical scavenging activity in aqueous extracts of different pH (2, 4, 7 and 9) from aerial parts of Glycyrrhiza glabra L. The content of phenolic compounds was maximal at pH 7 (14.13 mg GAE/g) and flavonoids at pH 9 (4.90 mg CE/g) and the total antioxidant capacity was maximal at pH 9 (13.43 mg AAE/g) and free radical scavenging DPPH activity was highest at pH 7 (IC50 value = 60.48 µg/ml). Thus, the aerial part is a good source of phytochemicals and also acts as a good antioxidant.
Nov 2021 DOI 10.14302/issn.2471-2140.jaa-21-3996
Singh SushilaCorresponding author
Department of Chemistry, CCS Haryana Agricultural University, Hisar, Haryana, India.
Plants are an important source of medicines since ancient times. The traditional system medicine’s use a variety of native plants to diagnose, prevent, and eliminate acute and chronic diseases.Asparagus racemosus(Willd.), also have been widely used for medicinal purpose and its extensively distributed in the tropics and subtropics of India, commonly known as Satawar, belongs to the family Asparagus. The purpose of this was to identify the phytochemicals and to assess the antioxidant potential in aqueous extracts prepared at different pH levels of Satawar tubers. The maximum amount of phenolics and flavonoids content was present at pH 9 i.e.18.88mg GAE/g and 2.83mg CE/g. The total antioxidant capacity was highest at pH 2 (15.96mg AAE/g) and IC50 values of DPPH free radical scavenging activity was the lowest at pH 7, 2582.85µg/mL. According to the whole study, this plant is a very good source of phytochemicals and acts as a powerful antioxidant.
Oct 2021 DOI 10.14302/issn.2471-2140.jaa-21-3960
Singh SushilaCorresponding author
Department of Chemistry, CCS Haryana Agricultural University, Hisar, Haryana, India.
When lipids are exposed to heat, light and oxygen, it leads to oxidation. The addition of antioxidants is required to preserve colour, flavour and vitamin destruction. Present study was, therefore, planned to investigate pod coat of pigeon pea as possible sources of natural antioxidants and to assess their efficacy in stabilization of crude soybean oil during normal storage (28 days at 50°C). Study revealed that acetone pod coat extract of pigeon pea showed richness in total phenolics (17.72 mg/g), flavonoids (9.00 mg/g) and tannins (2.21 mg/g) while the extract of ethyl acetate was found enriched in tocopherols content (9.56 mg/g). The IC50 value of acetone extract was found to be lowest, exhibited potent antioxidant activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric thiocyanate (FTC) methods. After adding synthetic and natural antioxidants in oil, Peroxide, p-Anisidine, Thiobarbituric acid value, Conjugated dienes, trienes and free fatty acids content were measured every 4 days. Acetone pod coat extract (2000ppm) of pigeon pea gave strong antioxidant efficacy in stabilization of crude soybean oil and hence could be recommended as natural antioxidants for food applications.The research explored the possibility of using pod coat of pigeon pea as imminent sources of green antioxidants and to evaluate their efficacy in stabilization of crude soybean oil.
Jul 2020 DOI 10.14302/issn.2471-2140.jaa-20-3478
R.A. Mans DennisCorresponding author
Department of Pharmacology, Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
Plant-based preparations are commonly used in Suriname (South America) as adaptogens. In this study, fifteen alleged adaptogenic Surinamese plants have been assessed for their antioxidant activity (AA), total phenolic contents (TPC), and total flavonoid contents (TFC). The investigated plants were Anacardium occidentale, Spondiasdulcis, Annona muricata, Euterpe oleracea, Oenocarpus bacaba, Luffa acutangula, Punicagranatum, Malpighia emarginata, Syzygiumaqueum, Syzygiumcumini, Averrhoa carambola, and Renealmiaalpinia (fruit); Hibiscus sabdariffa (calyx); as well as Aloe vera and Cestrum latifolium (leaf). Aqueous extracts (1 - 3,000 μg/ mL) were prepared. AA was determined by the FRAP and the DPPH assay. TPC and TFC were determined by the Folin-Ciocalteu’s and an AlCl3 colorimetric method, respectively, using gallic acid (GA) and rutin (R), respectively, as standards. Data are means ± SDs (n ≥ 3; P < 0.05). FRAP values and DPPH-scavenging activities correlated positively with each other and with TPC but not with TFC. The preparations from M. emarginata, A. carambola, A. occidentale, O. bacaba, C. latifolium, and H. sabdariffa displayed the highest FRAP values (54 ± 14 to 412 ± 30 µM Fe2+/100 μg), DPPH-scavenging activities (IC50 values of 33 ± 14 to 250 ± 50 μg/mL), and TPC (51 ± 4 to 280 ± 78 µM GAE/100 µg). TFC of all samples were ≤ 10 ± 3 RE/100 µg. The adaptogenic properties of these plants may (partially) be attributed to their high content of antioxidant phenolic compounds and may make them candidates of novel sources of health-promoting antioxidants.
Jan 2020 DOI 10.14302/issn.2379-7835.ijn-19-3144
Q. Almulaiky YaaserCorresponding author
Chemistry Department, Faculty of Sciences and Arts, University of Jeddah, Khulais, P.O. Box 355, Khulais, 21921, Saudi Arabia
In this study, the antioxidants and photosynthetic compounds of Verdolaga were examined. Compounds were extracted from distinctive segments of the verdolaga using various solvents such as methanol (40, 60, 80%), ethanol (40, 60, 80%), acetone (40, 60, 80%), and deionized water. The use of 80% methanol led to the highest extracted concentration of phenolic substances and flavonoids. The extracted products (Leaves, Stem strips, and Root strips) were evaluated for their radical scavenging capabilities with DPPH (IC50= 22.26, 20.56, and 32.10), and ABTS (IC50= 2.86, 3.70, and 5.24), reducing power (EC50= 15.70, 16.39, and 21.69), and peroxide scavenging activity (1C50= 1.717, 2.937, and 3.255), respectively. The extracted products were analyzed by a gas chromatography-mass spectrometer. Peroxidase, catalase, and polyphenol oxidase assays were completed for the crude extract of verdolaga’s leave, stem strips, and root strips. As indicated by these tests, extracts of the verdolaga’s roots, stems and leaves using 80% methanol yielded high antioxidant activity. The most elevated concentrations of extracted chlorophyll, lycopene, and carotenoids were from the leaves and the highest concentration of extracted tannin was noted from strips of stems. The highest measures of peroxidase and polyphenol oxidase were identified in root strips and the highest units of catalase was identified in leaves.
Sep 2017 DOI 10.14302/issn.2471-2140.jaa-17-1728
Md. Badrul IslamCorresponding author
The use of herbal medicine is becoming popular day by day due to toxicity and side effects of allopathic medicines. Considering the medicinal importance of the plant Murraya koenigii Linn (Curry leaf), the antioxidant activity (AC), total phenolic content (TPC), total flavonoid content (TFC), of different fractions of methanolic extract (DIA-ion resin adsorbed fraction, chloroform, Ethyl acetate and petroleum ether) of M. koenigii were investigated. Among the fractions, DIA-ion resin-adsorbed fraction showed the highest total antioxidant activity with absorbance 2.320±06 and petroleum ether fraction showed the lowest total antioxidant activity with absorbance 1.944 at 100 mg/ml concentration. The TPC were found range between 13.285 to 17.52 mg GAE/g while the highest amount of TFC recorded among the extracts was 16.65 mg CatE/g. DPPH free radical scavenging activity of different extracts of leaves was also measured where DIA-ion resin-adsorbed fraction had the highest free radical scavenging activity with IC50 value 15.53 µg/ml. In the present study phenolic compound were found to be the predominant components in the leaves of M. koenigii indicating that they are potent antioxidant.
Aug 2017 DOI 10.14302/issn.2471-2140.jaa-17-1541
Yu ZhiCorresponding author
College of Horticulture and Forestry Science, Huazhong Agricultural University, Key Laboratory of Horticultural Plant Biology, Ministry of Education, No. 1 Shizishan Street, Hongshan District, Wuhan City, Hubei Province, China 430070
In the present study, we investigated the chemical compositions, in vitro antioxidant and in vivo hepatoprotective activities of two tea polysaccharides (TPS), which were extracted from two different tea cultivars, Yingshuang (Camellia Senesis, T01) and Yunnan Dayezhong (Camellia Senesis, T09). Compared with T09-TPS, T01-TPS had lower contents of neutral sugar, protein, uronic acid and polyphenol. However, T01-TPS showed stronger scavenging abilities for transient free radicals of hydroxyl radical and superoxide anion radicals and lipid peroxidation inhibition effect, but weaker scavenging ability for stable free radical of DPPH. For hepatoprotective activity in vivo, the results demonstrated that both T01-TPS and T09-TPS could significantly prevent the increase of serum alanine aminotransferase and, aspartate aminotransferase levels, decrease the liver index, reduce the formation of malonydialdehyde and enhance the activities of superoxide dismutase, glutathione peroxidase and peroxidase in carbon tetrachloride-induced liver injury mice. These results suggest that T01-TPS and T09-TPS have potent antioxidant and hepatoprotective activities.
Feb 2016 DOI 10.14302/issn.2471-2140.jaa-15-887
Alabdul Magid AbdulmagidCorresponding author
ICMR-UMR CNRS 7312, Groupe Isolement et Structure, Campus Sciences, Bât. 18, BP 1039, 51687 Reims Cedex 2, France
A bioassay-guided fractionation of petroleum ether, EtOAc and n-BuOH soluble parts of the 80% hydromethanol extract was performed to investigate the antioxidant activity of Secamoneafzeliiaerial parts using DPPH free radical scavenging assay. The results revealed that EtOAc and n-BuOH soluble parts have moderate to good DPPH radical scavenging activity (EC50 = 139.3 and 30.5 μg/mL, respectively). Therefore, from the most active fractions of EtOAc and n-BuOH soluble parts were isolated two new flavonoid diglycosides quercetin-3-O-β-d-apiofuranosyl-(1→2)-α-l-rhamnopyranoside and genkwanin-8-C-β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside in addition to nine known compounds (2-10). Their structures were elucidated on the basis of spectroscopic data including 1D- and 2D-NMR and ESI-MS. The ability of the isolated compounds to scavenge the DPPH was evaluated. The new compound 1, quercitrin (3) and rutin (6) have antioxidant potential with EC50 values ranging from 8.4 to 13.6 µg/mL, compared to the standard ascorbic acid (EC50 7.4 µg/mL).
Dec 2015 DOI 10.14302/issn.2471-2140.jaa-15-715
Kevers ClaireCorresponding author
Plant Molecular Biology and Biotechnology and CEDEVIT B22, University of Liège Chemin de la Vallée, 4, Sart Tilman, 4000 Liège Belgium
Since a few years, more and more attention has been specifically given to dietary antioxidants as agents promoting health and preventing the incidence of diseases. As part of these efforts, analytical methods and assays have been developed to measure the antioxidant content in food substances. In this paper, the antioxidant capacity of 17 orange juices is determined by various assays (DPPH, ORAC, heamolysis, xanthine/xanthine oxidase) as the content in ascorbic acid and total phenolics. The results evidence all the complexity to evaluate the in vitro antioxidant capacity of foods. In very general terms, in spite of the wide utilization in these tests (FRAP, TAC, ORAC TRAP and others), their significance remains obscure. The discrepancy of the results and the absence of good correlation between the assays clearly highlight all the importance of understanding the strengths and weakness of assays evaluating antioxidant potential of a food at the risk of giving erroneous information to the consumer. It is clear that the use of "total antioxidant capacity" assays for the in vitro assessment of antioxidant quality of food does not be employed by food industrials as a marketing argument or for the assessment of the "wholesomeness" of a food.
May 2015 DOI 10.14302/issn.2379-7835.ijn-14-590
Jhaumeer Laulloo SCorresponding author
Department of Chemistry, University of Mauritius
The raw sunflower oil (SFO) has an undesirable flavour and odour. Therefore, to make it suitable for human consumption, the oil has to undergo a number of refining processes such as degumming, neutralization, bleaching and deodorization. During these refining processes, some of the phytochemicals present in SFO is lost. The aim of this study is to evaluate the loss in total phenolic, flavonoid and non-flavonoid contents and the antioxidant properties of the oil at the different chemical refining stages. The crude SFO oil has the highest total phenolic, flavonoid and non-flavonoid contents. The amount of phenolic compounds decreases as the oil undergoes different chemical refining processes. Results of this study indicated that the highest percentage loss of the phenolic compounds occurred during the deodorizing step.The statistical loss of the deodorized oil was 41.7, 63.9 and 27.6 % for total phenolic, flavonoid and non-flavonoid contents respectively. The free scavenging activity of sunflower oil was determined using DPPH and ABTS assays. The percentage scavenging activity ranged from 55.64 to 35.87 % for the DPPH assay while for ABTS assay the activity ranged from 59.46 to 31.43 % in a 50 mg/ml of SFO sample. This showed a decrease in antioxidant activity from crude to DNW to bleached and deodorized oil. The crude oil having the highest phenolic contents showed the highest antioxidant activity in both DPPH and ABTS assays.