EFFECT OF DIFFERENT ABIOTIC STRESSES ON ACETYLCHOLINESTERASE INHIBITION, ANTIOXIDANT ACTIVITY TOTAL PHENOL & FLAVONOID CONTENT OF SELECTED ALLIUM SPECIES: RESULTS FROM A 6-MONTH FIELD STUDY

Environmental factors influence plant growth, morphology, as well as nature and quantity of secondary metabolites. Modification of abiotic factors during plant growth can impact the production of bioactive phytoconstituents. A six-month field study was carried out to assess the effect of different abiotic stresses on bioactive compounds (flavonoids, phenols, quercetin), acetylcholine sterase (AChE) inhibition and antioxidant capacity of two selected Allium species i.e. Allium cepa L. (AC) & Allium sativum L. (AS; family Amaryllidaceae). AC and AS plants were grown for six months (from November 2018 to April 2019) on three different soil types (i.e. black, red, clay-loamy) and various stresses (salinity, water deprivation, flooding, fertilizer, metal, shade) were applied on the plants. At the end of the season, plants were collected, dried and plant yield was determined. Hydro alcoholic extracts of all samples were prepared. Extract yield, total flavonoids (TFC), total phenols (TPC), AChE inhibition, and antioxidant activity were determined in all the extracts. The results show the varied response of AC & AS plants to different soil types and stresses. AS plants grown in red soil with salt stress and AC plants on red soil with fertilization give higher biomass yield. AC plants grown in black soil and AS in red soil under metal stress have the highest TFC, TPC, AChE inhibition, and antioxidant activity. Hence these conditions may be recommended for incorporation in cultivation practices of these valuable medicinal plants. This would ensure a commercial supply of plants with higher phenol and flavonoid content and better activity.