• Food Science and Preservation
• /
• v.7 no.2
• /
• pp.211-217
• /
• 2000

The effects of Citrus flavonoids, hesperetin, hesderidin, naringenin, and naringin, on nonenzymatic lipid peroxidation were studied in three different in vitro experimental models. Hesperetin showed the most antioxidant effect in this experimental condition by measuring the malondialdehyde production using the thiobarbiturate and thiocyanate methods, the lipid peroxidation of microsomal membranes, and DPPH (${\alpha},{\alpha}'-diphenyl-{\beta}-picrylhydrazyl$) method. The antioxidative activity of the flavonoid aglycone forms, hesperetin, Citrus aglycone flavonoid, suggest the most antioxidant effect in this experimental condition, and this effect indicate more potent in the aglycones than their corresponding glycosides.

• Food Science and Biotechnology
• /
• v.18 no.3
• /
• pp.672-681
• /
• 2009

The aim of this study was to evaluate the antioxidant activities of enzymatic digests from citrus by-products (CBPs) prepared by high speed drying (HSD). HSD needs a short time (60 min) for drying and can be used in a commercial scale. Enzymatic digests were prepared from the CBPs using 6 enzymes such as aminoglucosidase (AMG), celluclast, pectinex, termamyl, ultraflo, and viscozyme. Antioxidant activities of AMG digest from CBPs were evaluated by different in vitro models such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, alkyl, $H_2O_2$ scavenging, metal chelating, lipid peroxidation, and comet assays, and exhibited strong activities. The antioxidant compounds were detected by an high performance liquid chromatography (HPLC) coupled on-line to an 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid ($ABTS^+$) scavenging detection system, and found that hesperidin was the key compound. Therefore, the results obtained in this study suggest that HSD is an effective method to transform wet CBPs into dried form, and CBPs are potential source of natural antioxidant.

• Preventive Nutrition and Food Science
• /
• v.20 no.3
• /
• pp.210-214
• /
• 2015

Grape pomace is an abundant source of underutilized winery by-products. Polyphenols were extracted from grape pomace using cellulase and gluco-amylase enzymes. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Folin-Ciocalteu's assays were used to measure antioxidant activity and total polyphenolic contents. Both cellulase, and gluco-amylase digested grape pomace showed efficient radical scavenging activity. In addition, the total polyphenolic contents of cellulase digested grape pomace showed lower concentrations were effective compared to higher concentrations, whereas glucoamylase enzyme did not show remarkable variations. The DPPH radical scavenging activity and total polyphenolic contents were significantly higher in the cellulase digested grape pomace compared to the gluco-amylase digested and the not digested grape pomace. It is notable that enzymatic digestions were efficient for extracting polyphenols from grape pomace. The underutilized grape pomace polyphenols can be further used for food safety as a natural antioxidant.

• Korean Journal of Food Science and Technology
• /
• v.53 no.2
• /
• pp.126-132
• /
• 2021

Cheonggukjang (CGJ) is a famous traditional Korean food that is typically produced by fermenting steamed soybean seeds and has a unique flavor and taste. The objective of this study was to evaluate the effect of addition of lotus seeds on the quality and antioxidant activities of CGJ. Color value, 1,1-diphenly-2-picrylhydrazyl radical scavenging potential, and the amounts of total polyphenol, total flavonoid, mineral, and free amino acid were evaluated. The CGJ sample produced with lotus alone or a mixture of soybean and lotus produced in Korea showed relatively high antioxidant potential. The amount of essential and total free amino acids was also high in the sample prepared with lotus seeds grown in Korea. On the other hand, the total mineral content was low in the lotus-based samples. The results indicated that a mixture of an equal proportion of soybean and lotus seeds could be a good option to prepare nutritious CGJ.

• Korean Journal of Food Science and Technology
• /
• v.53 no.4
• /
• pp.463-469
• /
• 2021

Bioactivities of curcumin, a major pigment of Curcuma longa L., have been widely investigated. In this study, the antioxidant and cytotoxic properties of curcumin and its analogs including ferulic acid, dibenzoylmethane (DBM), and tetrahydrocurcumin (THC), and their structure-activity relationships were assessed. Ferulic acid, THC, and curcumin showed strong scavenging activities against several radicals and exhibited considerable lipid peroxidation inhibitory activity. Curcumin showed the strongest cytotoxic activities against HeLa, HCT-116, IEC-6 and INT 407 cells, whereas ferulic acid did not show any cytotoxic effect up to 100 µM against these cell lines. Cytotoxicity of curcumin and THC was significantly enhanced by superoxide dismutase and diminished by N-acetylcysteine. The combination treatment of curcumin and ferulic acid enhanced the cytotoxicity, whereas the combination of curcumin and DBM offset their toxicity. These results suggest that methoxy phenolic and β-diketon moieties are crucial for the antioxidant- and cytototoxic activities of curcumin, respectively.

• The Korean Journal of Community Living Science
• /
• v.23 no.3
• /
• pp.245-254
• /
• 2012

This study was performed to determine the component analysis and measurements of antioxidant activities from natural seasoning containing Lentinus edodes powder (NSLP) in order to detect the biological activities and develop novel functional resources. It was extracted with 70% ethanol and then further fractionated to hexane, chloroform, ethyl acetate, butanol and water. Methods used in this experiment were measured to examine total polyphenol contents and total flavonoid contents, reducing power and Superoxide dismutase-like activity. Composition analysis were highly composed of carbohydrate as 44.1%. The minerals of different organics were highly composed of sodium as 5,073 mg/100g. There were seventeen total amino acids in NSLP. The glutamic acid content was high up to 16.9 mg/g and aspartic acid, lysine, leucine, alanine were followed. Predominant fatty acid was linoleic acid (62.7%) in NSLP. Contents of total polyphenols in butanol fraction from NSLP were 16.38 mg/100mL. While overall butanol fraction have higher reducing power than ethanol extract, after the addition of 400 ${\mu}g/mL$ butanol fraction, auto oxidation of pyrogallol decreased to 83.62% as a result of superoxide dismutase-like activity. A positive correlation was observed between total polyphenol, flavonoid and antioxidant activities.

• Korean Journal of Food Science and Technology
• /
• v.52 no.5
• /
• pp.503-509
• /
• 2020

The present study investigated the effects of dry and moist heat treatments on total phenols, total anthocyanins, and antioxidant activity levels in black chokeberry (Aronia melanocarpa) fruits. Lyophilized chokeberry powder samples were heated in a drying oven at 60, 100, 160, 180, and 200℃ for 20, 40, or 60 min. Finely ground fresh chokeberry fruits were heated in water at 60, 80, and 100℃ for 20 min, and bioactive compound and antioxidant activity levels were measured. The bioactive compounds and antioxidant activity decreased with increasing temperature and treatment duration. Antioxidant activity was preserved at 160℃ or lower without significant loss for dry heating, whereas moist heat treatment increased both bioactive compounds and antioxidant activity with increasing temperature.

• Fisheries and Aquatic Sciences
• /
• v.14 no.4
• /
• pp.289-293
• /
• 2011

The antioxidant and cholinesterase inhibitory activities of methanol, pretanol, and acetone extracts of Eupausia superba were investigated and their bioactivities compared. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis[3-ethylbenzthiazoline-6-sulfonic acid] ($ABTS^+$) radical-scavenging activities and reducing power assays were used to determine antioxidant activities, and Ellman's colorimetric methods were applied to evaluate cholinesterase inhibitory activity. Although all extracts were positive, Acetone extract of E. superba showed the highest activities. However, these showed moderate or no inhibitory activity against butyrylcholinesterase. Moreover, the total carotenoid contents of the organic solvent extracts followed the same order as their antioxidant and acetylcholinesterase inhibitory activities. These results suggest that E. superba is a potential source of natural antioxidants and cholinesterase inhibitors.

• Journal of the Korean Society of Food Culture
• /
• v.36 no.2
• /
• pp.210-217
• /
• 2021

This study evaluated the biological activity and cytoprotective effect of guava (Psidium guajava L.) branch against oxidative stress. The contents of vitamin C, beta-carotene, total carotenoids, quercetin and catechin determined were 26.783, 43.676, 65.083, 58.245, and 8.309 mg/100 g, respectively. To measure antioxidant activity, the guava branch was extracted using various concentrations of ethanol (60, 80, or 100%) and water. The highest content of polyphenols (0.245 mg gallic acid equivalent/mg residue) and flavonoids (0.128 mg cathechin equivalent/mg residue) was found in the 100% ethanol extract of the branch (E100). Moreover, E100 also possessed the highest radical scavenging activities and showed the highest inhibition rate of α-glucosidase (77.692%). E100 was the most effective extract to impart cytoprotectant activity against oxidative stress in HepG2 cells. Taken together, our results determine the promising antioxidant activity of guava branch, and indicate the potential to be applied as a natural antioxidant.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.4
• /
• pp.684-691
• /
• 2014

This study was carried out to investigate the antioxidant activity and changes in major functional components of fermented Gastrodia elata Blume. Fermented G. elata Blume powder by Phellinus linteus repeated thrice ($3^{rd}$ FGP) showed more DPPH radical scavenging activity than a non-fermented G. elata Blume powder (NFGP), and once fermented G. elata Blume powder ($1^{st}$ FGP) at a concentration of 500 and 1,000 ppm. Free radical scavenging activity of $3^{rd}$ FGP was similar to that of BHA at a dose of 1,000 ppm. Moreover, the ABTS radical scavenging activity of the $3^{rd}$ FGP increased compared to NFGP and $1^{st}$ FGP at a concentration of 31.25 ppm. Total polyphenols and flavonoid contents were increased as fermentation progressed. Ergothioneine content was increased more than 8 times in the $1^{st}$ FGP, 3 times in the $3^{rd}$ FGP, respectively than NFGP. In conclusion, this study indicated that the antioxidant activity and functional component contents of G. elata Blume were increased depending on the fermentation number.