THERAPEUTIC POTENTIAL OF BIOACTIVE PEPTIDES DERIVED FROM CHEDDAR CHEESE

Abstract

Growing perception concerning diet and health has extended the need to exploit the nutritious, biologically active and sustainable food products. The present study was designed to evaluate the potential role of water-soluble peptides (WSPs) extract derived from buffalo and cow milk Cheddar cheeses with special reference to anti-hypertensive, anti-thrombotic, anti-oxidant, anti-inflammatory and anti-cancer activities. Purposely, the WSPs fractions collected at different stages of cheese ripening were subjected to assess the degree of proteolysis, peptides profiling by RP-HPLC and in vitro assays for bioactivities of interest. The ripening period was accompanied by a significant (p<0.01) increase in the level of water-soluble nitrogen and non-protein-nitrogen. The cheeses expressed peptide peak development during ripening, however few qualitative differences were observed in chromatograms of their WSPs extract. There were slight differences concerning the number, area and height of peaks during whole investigation period. The angiotensin converting enzyme- inhibitory and anti-thrombotic activity of WSPs increased progressively during 180 days of cheese maturation. Regarding the in vitro radical scavenging potential, the WSPs extracts were demonstrated to be potent scavenger of DPPH and ABTS radicals and the activities increased progressively with ripening period. Moreover, results indicated the dose-dependent inhibition of radicals. Comparatively, the highest activities were noticed in the peptide extract obtained from buffalo milk Cheddar cheese. The protective role of WSPs extract on cell viability and cellular antioxidant activity in RAW-264.7 macrophages (LPS-stimulated) and Caco-2 (tert-butyl hydroperoxide-induced) cell lines, indicated that the intracellular ROS production decreased significantly upon treatment with the selected doses of WSPs extract. However, maximum activity was noticed at 150 and 180 day of ripening in a dose-dependent manner. The in vitro anti-inflammatory potential of cheese extract was expounded using RAW-264.7 macrophages on the basis of nitric oxide (NO) production in these cells. The extracts effectively inhibited the NO production in cells without affecting their viability. The cell viability, cell cycle arrest and apoptosis were performed to explore the anti-cancer activity using lung (H1299) and colon (HT-29 & HCT-116) cancer cell lines. Cheese extracts of 120, 150 and 180 of ripening days showed marked anti-proliferation activity towards cancer cells in dose-dependent fashion. The extracts also caused significant changes in cell cycle distribution in comparison to the control cells. The substantial dose-dependent increase in the percentage of cells population in G0/G1 phase was observed in colon cells while WSPs extracts induced G2/M phase cell cycle arrest in lung cancer cell line at rate of 400 μg/mL and 500 μg/mL. Moreover, these extracts also induced extensive early and late apoptosis in all cancer cells. In conclusion, the promising health potential of Cheddar cheese can offer a perspective to reduce the risk of disorders associated with cardiovascular diseases, oxidative stress, inflammation and cancer.