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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.
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.
Dec 2015 DOI 10.14302/issn.2471-2140.jaa-15-797
Kevers ClaireCorresponding author
Plant Molecular Biology and Biotechnology and CEDEVIT B22, University of Liège Chemin de la Vallée, 4, Sart Tilman, 4000 Liège Belgium
Liège syrup is a Belgian traditional cooked fruit foodstuff, produced mainly from apples and pears. The process includes several hours of heating at high temperature during which complex chemical reactions occur, such as Maillard condensation between reducing sugars and amino acids. Aiming at understanding the modifications of the fruit juices during heating, different parameters were monitored throughout the process. It was shown that hydoxymethylfurfural was formed during the first step of concentration by heating. At the end of the process, hydroxymethylfurfural had totally disappeared and the deep brown color of the product suggested that this compound was transformed into melanoidins. A parallel increase in antioxidant capacity was also observed. To determine optimal conditions to reach high melanoidin content and high antioxidant capacity, different in vitro model systems were compared. It was shown that different combinations of an amino acid with glucose or fructose led to different levels of hydroxymethyfurfural, of melanoidins and antioxidant capacity. After heating of apple or pear puree, an increase of the antioxidant capacity and the hydroxymethylfurfural and melanoidin contents was observed when the heating time was doubled. An increase of the pH from 5 to 9 in apple marmalade’s also induced an increase in antioxidant capacity and in hydroxymethylfurfural and melanoidins. However it was not the case in pear marmalade where only the increase in antioxidant capacity was observed. These results suggest that some parameters of the processing could be modified to improve the health-promoting effect of this traditional food (antioxidant properties and composition in hydroxymethylfurfural and melanoidins). The main factors affecting the quality of the final product were the cooking times, the temperature, the pH, the addition of reducing sugars or amino acids.
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 2019 DOI 10.14302/issn.2638-4469.japb-19-3051
Ahmed Ismail HebatollahCorresponding author
Botany Department, Faculty of Science, Ain Shams University, Cairo, Egypt
Triacontanol (TRIA) role in improving growth, physiological activities and tolerance against abiotic stresses has been reported. Yet, the mechanism by which TRIA executes its effects remains elusive. This work therefore studied the possible role of TRIA exogenous application in counteracting the adverse effects of nickel (Ni) treated maize seedlings. Maize seedlings (15-day-old) were grown in washed sand irrigated with nutrient solution provided with 100 μM NiCl2. Two concentrations of TRIA (25 and 50 µM) were applied twice as a foliar spray for Ni-stressed seedlings. Shoot and root growth attributes, Ni content, and antioxidant defence systems of maize seedlings were determined. Ni treatment reduced the shoot and root length and biomass, causing necrosis of the old leaves,greater reduction was shown in the roots. The shoot and root length was negatively correlated with their Ni content, which was consistent with their content of H2O2, but not with their malondialdehyde (MDA) content. As the roots had the greatest Ni content, maximum peroxidase (PX) and glutathione reductase (GR) activity as well as the highest ascorbic acid (ASA) and reduced glutathione (GSH) content were observed in the roots. The Ni-induced deleterious effects were alleviated by foliar application of TRIA concentrations. Also, TRIA treatment minimized root Ni content, whereas it maintained the shoots unharmed by Ni. Such mitigative effects of TRIA are explained by its key role in enhancing antioxidant capacity (expressed as IC50), increased PX and ascorbate oxidase (AO) activity, GSH, and total phenolic contents.
Jun 2019 DOI 10.14302/issn.2471-2140.jaa-19-2747
M. S. López-CortezCorresponding author
Numerous studies have reported the health benefits of consuming fruits and vegetables that contain antioxidant properties. Within the group of fruits considered exotic, some are accessible and only consumed in their place of origin, such as soursop, noni, kiwi, pitahaya, and others. Anacardiumoccidentale, cashew, is a crop native to the Brazilian northeast that has excellent medicinal and nutritional properties. Because few studies have characterized cashew produced in Mexico, in the present work, the physicochemical properties and antioxidant capacity of cashew apple (red and yellow varieties) and its nut were studied. The content of total phenolic compounds and the antioxidant capacity were higher in the nut (174.19±20.98 GAE mg/100 g db) while cashew red pulp showed a superior value of the phenol content (159.75±12.91 GAE mg/100 g db) to that of yellow cashew pulp (151.9±5.23 GAE mg/100 g db). A high value was obtained for the TPC of the husk of cashew nut (74.30 mg GAE/g) compared with those of the kernel and false fruit. Red cashew presented a higher antioxidant capacity at 77.65 μmol Trolox/g and was superior to that of the kernel (38.52±2.9 μmol Trolox/g). Because cashew apple is usually discarded, a marmalade based on the pulp is proposed as an alternative for its conservation because it has a high content of phenolic compounds that is conserved for six weeks of shelf life.
Mar 2018 DOI 10.14302/issn.2575-1212.jvhc-18-2013
A Halawa AmalCorresponding author
Department of Forensic Medicine and Toxicology, Faulty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
Lipopolysaccharide (LPS) is a component of the outer membrane of gram negative bacteria. LPS challenging allows switching transcription of proinflammatory cytokines on via over stimulation of Toll-like receptors (TLRs) signaling pathway with subsequent pathogenic inflammatory response. We investigated the possible reproductive toxicity of LPS in male Wister albino rats. Oxidative stress markers, antioxidant status and caspase-3 activity were analyzed in testicular tissues of rats exposed to either saline or LPS (4 mg/kg BW, ip; 0.18 of the LD50). The samples were collected at 6 h and 72 h after injection of LPS. A significant reduction in testicular reduced glutathione (GSH), glutathione-S-transferase (GST) and superoxide dismutase (SOD) was observed at 72 h compared to control group. Total antioxidant capacity was decreased at 6 h with additional significant reduction at 72 h. Catalase activity was reduced significantly at both 6 and 72 h. Malondialdehyde (MDA) was increased (P ≤ 0.05) in LPS injected rats without variation between 6 and 72 h. A significant increase in nitric oxide (NO) was observed at 72 h after injection. A time-dependent increase in LPS-treated groups was observed in the concentration of caspase-3.Histopathological analysis revealed degenerative changes and necrosis of seminiferous tubules after 6 h with further accumulation of eosinophilic edematous transudate in its lumen after 72 h. In conclusion, by increasing time of exposure, LPS induced lipid peroxidation, oxidative stress, reduced testicular antioxidant capacity and encouraged testicular apoptosis which could be possible mechanisms for impairment of testicular function.
Jun 2015 DOI 10.14302/issn.2471-2140.jaa-14-617
Srinivasa Rao P.V.L.N.Corresponding author
Department of Biochemistry, Sri Venkateswara Institute of Medical Sciences, Tirupati, India.
Background: Antioxidants play an important role in maintenance of human health and prevention of disease. Effective supplementation of antioxidants requires laboratory monitoring of antioxidant status. An understanding of the methods used to determine the TAS helps in better interpretation of values obtained using a particular method and also to select a suitable method. Material and Methods: Forty subjects including 25 healthy volunteers and 15 patients diagnosed with rheumatoid arthritis were studied. All samples were analysed for TAS using Ferric reducing ability of plasma (FRAP) method and Trolox equivalent antioxidant capacity (TEAC) assay. Results: Mean TAS values obtained by TEAC method were higher than those obtained by FRAP method (p<0.0001); no difference was observed when TEAC values were corrected for proteins and FRAP values were corrected for uric acid (p=0.420). No correlation was found between TEAC and FRAP methods (p=0.102). However, when TEAC was corrected for proteins, positive correlation was observed with FRAP (p=0.044). There was agreement between the two methods when TEAC values were corrected for proteins. Conclusion: Although the reaction conditions differ, similar compounds react in both the assays and thus TEAC and FRAP assays are comparable. However, the two methods differ with respect to –SH groups and uric acid contributions. This contributes to the higher TAS values obtained by TEAC assay. Thus, in conditions with altered protein or uric acid levels, the two methods may not be used interchangeably. The TEAC assay is to be corrected for protein for comparison of reports of the two assays.