Phytochemicals, Antioxidant and Antidiabetic Activities of Extracts from Miliusa velutina Flowers

Abstract

The flowers of M. velutina were extracted with ethanol to obtain a crude extract that was consecutively extracted using n-hexane, dichloromethane, ethyl acetate and water. The crude extract and fractions were studied for the chemical composition and antioxidant and antidiabetic activities. The extracts had various phytoconstituents, namely steroids, flavonoids, tannins, saponins, alkaloids and glycosides. The aqueous extract had the highest total polyphenol (12.6 mg GAE/g extract) and total flavonoid (205.6 mg QE/g extract) content. The aqueous extract exhibited the strongest antioxidant activities in the ferric reducing antioxidant power assay (EC50 = 4.0 µg/mL), reducing power assay (EC50 = 78.1 µg/mL), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid radical cation assay (EC50 = 48.2 µg/mL), total antioxidant capacity assay (EC50 = 8.7 µg/mL) and 1,1-diphenyl-2-picrylhydrazyl assay (EC50 = 9.3 µg/mL). The aqueous extract showed the strongest inhibitory effect on the activity of α-amylase (IC50 = 376.6 μg/mL) and α-glucosidase (IC50 = 69.7 μg/mL). The results showed that the aqueous extract of M. velutina flowers can be a promising candidate for the control of diabetes and oxidative stress. This is the first report about the chemical components and antioxidant and antidiabetic activities of M. velutina flower extracts.

Antioxidant activity and antidiabetic activities of Northern Thai indigenous edible plant extracts and their phytochemical constituents

“…However, the lower amount of phenolic was observed when compared to that of total flavonoids in this study. The similar result could be previously observed and explained by Anh et al. (2021) .…”

“…Many published studies have suggested that the antioxidant activity of plant extracts is related to their antidiabetic activities and antiglycation activity. As demonstrated by Anh's research, the extracts from Miliusa velutna flowers showed a positive correlation between their antioxidant activity and their capacities to inhibit the carbohydrate digestive enzymes (α-amylase and α-glucosidase) ( Anh et al., 2021 ). In addition, some edible and medicinal plants have high antioxidant activity, exhibited strong antiglycation activity ( Kaewnarin et al., 2014 ).…”

“…In addition, there is a limitation of Folin-Ciocalteu reagent usually used for the determination of total phenolic content in term of its specificity because it can react not only the phenolic compounds but also any other reducing molecules in tested samples. While AlCl 3 reagent will specifically react with functional groups in the flavonoid molecules such as keto, hydroxyl, and ortho-dihydroxyl groups ( Anh et al., 2021 ).…”

Phytochemical Analysis, In Vitro Free Radical Scavenging, and LDL Protective Effects of Different Solvent Fractions of Calotropis procera (R.) Br. Root Bark Extract

“…EAF showed the highest phenolic content while favonoid content was higher in DMF. Te results are in agreement with the previously reported studies [43,44].…”

Tối ưu hóa quy trình ly trích cao chiết lá xạ đen (Celastrus hindsii) giàu polyphenol, flavonoid có hoạt tính kháng oxy hóa và kháng đái tháo đường in vitro

“…Trong các thử nghiệm kháng oxy hóa ở trên, tinh chất trolox được sử dụng làm đối chứng dương. Các hoạt động kháng oxy hóa của cao tối ưu LXĐ được so sánh với hoạt tính của trolox và cao LXĐ (cao LXĐ là cao được chiết xuất trong điều kiện bình thường theo mô tả của Phụng (2007) và Anh et al (2021), cụ thể như sau: ethanol 99,5% (v/v), nhiệt độ chiết 30 ○ C, thời gian 24 giờ và tỷ lệ nguyên liệu/ dung môi là 1/10 (w/v)) bằng cách tính toán nồng độ (µg/mL) mà cao tối ưu LXĐ, cao LXĐ hoặc trolox có thể khử hoặc trung hòa 50% các gốc tự do (effective concentration of 50%, EC 50 ).…”