ABSTRACT
Dementia is a global health problem that requires severe treatment. People with dementia who consume vegetablesevery day can reduce the risk of dementia. Alzheimer’s is one of the diseases that are characterized by dementia, whichresults in decreased neurotransmitter acetylcholine. This study was to investigate the acetylcholinesterase (AChE)enzyme inhibitory activity of various vegetables that are widely used by Indonesian Sundanese and Javanese ethnics. Inthis study, total phenolic and flavonoid content were analyzed for the determination of active compounds of the extracts.Ethanol extracts of 13 vegetables have been tested for AChE inhibitory activity using Ellman's colorimetric method in96-well plate. Four types of extracts (Cosmos caudatus, Nasturtium officinale, Nothopanax fruticosus, and Ocimumamericanum) had higher total phenolic and flavonoid content than other extracts. Vegetable extracts that had IC50 valuesof less than 1,000 µg/ml were C. caudatus and O. americanum. Both of these extracts were partitioned with n-hexaneand water. The IC50 values of water fraction of C. caudatus and n-hexane fraction of O. americanum were 325.0 ± 18.3and 374.4 ± 42.1 µg/ml, respectively. These results showed that fractions had a potential inhibitor of AChE, and thechemical components (phenolic, flavonoid, and terpenoid) can be isolated to find the active compound.
ABSTRACT
Objective:To determine antioxidant activity and phytochemical content from various tubers extracts of sweet potato (Ipomoea batatas) and to explore the correlation of phytochemical content with their antioxidant activities.Methods:Antioxidant activities were tested using DPPH and FRAP assays.Total phenolic was calculated by Folin-Cioealteu reagent,flavonoid content by Chang's method and correlation with their antioxidant activities were analyzed by Pearson's method.Results:PO2 showed highest antioxidant activity,which had the lowest IC50 DPPH (10.54 μg/mL) and the lowest EC5o FRAP (11.14 μg/mL).PO2 showed the highest total phenolic (11.91 g GAE/100 g) and total flavonoid content (17.83 g QE/100 g).There were significantly negative correlation between total phenolic content and flavonoid content in sample PO with their IC5o DPPH and EC5o FRAP.IC50 DPPH of sample PP and PO showed significantly positive correlation with their EC5o FRAP.Conclusions:Result of DPPH method shows that all different ethyl acetate and ethanolic tubers extracts of four varieties of sweet potato are classified as strong and very strong antioxidant.Result of DPPH and FRAP methods indicates that phenolic and flavonoid compounds in sample PO contributes together to antioxidant activities.Antioxidant activities of sample PP and PO by DPPH method are linear to FRAP method.