Hoạt tính kháng oxy hóa và kháng nấm của một số cao chiết thực vật thuộc họ gừng (Zingiberaceae) và họ củ nâu (Dioscoreaceae)

Abstract

The antioxidant and antifungal activity of ethanol extracts of Curcuma longa, Curcuma yunnanensis, Hedychium coronarium, Alpinia conchigera, Dioscorea bulbifera, Dioscorea membranacea, Dioscorea hispida and Dioscorea pentaphylla were tested. The highest total polyphenol (44,87±0,14 mg GAE/g extract) and flavonoid (110,75±6,38 mg QE/g extract) content were observed in Curcuma longa extract. The correlation was observed between biological activities and the amount of polyphenol, flavonoid compounds. All extracts exhibited antioxidant activity in FRAP (ferric reducing-antioxidant power), ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and RP (reducing power) assay. Poisoned food technique was used to determine the inhibition of mycelial growth, minimum inhibitory concentration, and minimum fungicidal concentration of the extracts on the test pathogens. The C. longa produced complete mycelial growth inhibition in Corynespora cassiicola pathogens at a concentration of 5,000 µg/mL after three days of incubation. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the C. longa on the test fungi were in the range of 2,500-5,000 ����L/mL and >5000 ����L/mL, respectively. These findings confirm the fungicidal properties of plants extract and their potential use in the management of economically important C. cassiicola and as possible alternatives to synthetic fungicides. C. longa used in this study could be potential sources of new antifungal and antioxidant.