Phenolic contents, antioxidant and α-glucosidase inhibition properties of Nepalese strain buckwheat vegetables

The sprouts, microgreens and leafy greens of common and tartary buckwheat of Nepalese strain were compared for the phenolic contents and biological activity. The tartary buckwheat samples expressed higher total phenolic and flavonoid contents compared to the common buckwheat. The sprouts had the highest total phenolic contents (9333.48 ± 150.23 and 6976.21 ± 213.65 mgGAE/100g dw in tartary and common buckwheat, respectively) whereas, the highest total flavonoid content was present in the leafy greens (7635.39 ± 141.40 and 4414.61 ± 70.85 mgRE/100g dw in tartary and common buckwheat respectively). The high performance liquid chromatography (HPLC) results revealed that the tartary buckwheat vegetables had higher rutin, (3800.28 ± 434.41 mg/100g in leafy greens), quercetin (159.75 ± 9.04 mg/100g in sprouts) and chlorogenic acid (293.47 ± 65.06 mg/100g in microgreens) contents than those of common buckwheat. However, other phenolics like vitexin, isovitexin, orientin and isoorientin contents were more abundant in common buckwheat. In biochemical assay, all three types of vegetable of common and tartary buckwheat showed higher antioxidant and α-glucosidase inhibition effect in dose dependent manner. Based on these results, it can be conformed that all the vegetables (microgreens, sprouts and leafy greens) of both varieties of buckwheat of Nepalese strains can be regarded as a potent sour ce of functional food.Key words: Antioxidant, α-glucosidase, buckwheat vegetables, Nepalese strain buckwheat, phenolics

Antioxidant activity and quantitative estimation of azadirachtin and nimbin in Azadirachta Indica A. Juss grown in foothills of Nepal

The leaf and bark fraction extracts of Azadirachta indica A. Juss. (neem) grown in the foothills (subtropical region) of Nepal were evaluated for their antioxidant activity, total phenolic (TP) and totalflavonid (TF) contents. HPLC method was employed to quantify the amount of azadirachtin and nimbin present in the seed, leaf and the bark extracts of neem. The result showed that the highest azadirachtincontent was found in the methanolic extract of the seed (3300 ìg/g dw). Similarly, the hexane fraction of bark showed the highest nimbin content (271 ìg/g dw) followed by the methanolic extract (260 ìg/g dw).Antioxidant activity was determined by measuring 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, hydroxyl radical scavenging activity, DNA protection assay, metal chelating and the inhibition of peroxidation using linoleic acid system and their results were found at different magnitudes of potency. The results of TP content expressed in tannic acid equivalents ranged from 66.63 to 629.04ìg/mg in the bark extracts and 23.85 to 237.00 ìg/mg in the leaf extracts. Likewise, the content of TF expressed in quercetine equivalents ranged from 12.87 to 17.07 ìg/mg in the bark and 13.72 to 93.17 ìg/mg in the leaf extracts

In vitro antioxidant, collagenase inhibition, and in vivo anti-wrinkle effects of combined formulation containing Punica granatum, Ginkgo biloba, Ficus carica, and Morus alba fruits extract

Amal Kumar Ghimeray,1 Un Sun Jung,1,2 Ha Youn Lee,1 Young Hoon Kim,1 Eun Kyung Ryu,1 Moon Sik Chang11R&D Center, Natural Solution Co., Ltd, Gojan-dong, Namdong-gu, Incheon, Republic of Korea; 2Department of Horticultural Biotechnology, Kyung Hee University, Yongin, Republic of KoreaBackground: In phytotherapy, the therapeutic potential is based on the combined action of different herbal drugs. Our objective was to evaluate the antioxidant, anti-collagenase (in vitro), and anti-wrinkle (in vivo) effect of combined formulation containing Ginkgo biloba, Punica granatum, Ficus carica, and Morus alba fruits extract.Methods: Antioxidant evaluation was based on the scavenging activity of free radicals (1,1-diphenyl-2-picrylhydrazyl, H2O2, and O2-) and the anti-collagenase activity was based on the reduction of collagenase enzyme in vitro. In an in vivo study, 21 female subjects were examined in a placebo-controlled trail. Facial wrinkle, especially the crow's feet region of eyes, was treated with topical formulated 2% cream for 56 days and compared with the placebo.Results: In the in vitro study, the combination of fruits extract showed a higher antioxidant activity which was comparable with the positive standard (ascorbic acid, butylated hydroxyanisole, and Trolox). The data also showed a dose-dependent inhibition of collagenase. In the in vivo study, treatment with 2% formulated cream for 56 days significantly reduced the percentage of wrinkle depth, length, and area with 11.5, 10.07, and 29.55, respectively.Conclusion: The combined formulation of fruit extracts showed excellent antioxidative and anti-collagenase activity as well as a significant effect on anti-wrinkle activity on human skin.Keywords: antioxidant, anti-collagenase, anti-wrinkle, fruits, topical formulatio