Screening of secondary metabolites, bioactive compounds, in vitro antioxidant, antibacterial, antidiabetic and anti-inflammatory activities of chia seeds (Salvia hispanica L.)

Abstract

Recent research studies indicate the role of functional foods in preventing the development of complications associated with type 2 diabetes mellitus. Chia seeds are an excellent source of dietary fibre, essential fatty acids, micronutrients and non-nutritive components. The objective of the study was to evaluate the antioxidant, antibacterial, antidiabetic and anti-inflammatory potential of chia seeds. TPC and TFC were estimated using Folin-Ciocalteu Reagent and Alumininum Chloride method. The antioxidant activity was determined using DPPH● radical, ABTS●+ radical, Superoxide (O2-) radical, Fe3+ reducing and phosphomolybdenum reduction assay. Agar well diffusion method was used to determine the antibacterial activity against Escherichia coli, Proteus vulgaris, Shigella flexneri, Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus. Antidiabetic and anti-inflammatory activities were evaluated using alpha amylase inhibition assay and heat induced haemolysis method. Volatile functional compounds were identified using Gas chromatography mass spectrometry. Upon quantification, TPC and TFC were found to be 850.67±14.14µg/mg GAE and 171.21±12.86µg/mg QE. Free radical scavenging activity of chia seeds was ranked in the order of DPPH● radical >ABTS●+ radical > Superoxide (O2-) radical. The capability of chia seeds to function as electron donors was evident through its strong reducing power. With regard to antibacterial activity, maximum inhibition was observed for Staphylococcus aureus, with a zone of inhibition of 31mm at 500µg/mL. Results of antidiabetic assay highlighted the alpha amylase inhibitory action of chia seeds with an IC50 value of 121.46µg/mL. The anti-inflammatory activity of chia seeds increased linearly in a dose dependent manner. GC-MS analysis showed the presence of functionally active compounds such as coumarine, napthoquinone, phytol, fatty acids, flavone and flavone derivatives. Findings of the study highlight that chia seeds have several essential therapeutic properties. Furthermore, clinical studies are required to validate the role of chia seeds in preventing the development of complications associated with type 2 diabetes mellitus.