In recent times, the status of some fermented foods which are considered as functional foods that confer health benefits in certain disease conditions has grown rapidly. The health benefits of fermented foods are due to the presence of probiotic microbes and the bioactive compounds formed during fermentation. Microbes involved and metabolites produced by them are highly species specific and contribute to the authenticity of the fermented foods. Several studies pertaining to the effect of fermented foods on various disease conditions have been conducted in recent years using both animal models and clinical trials on humans. This review focuses on the impact of fermented foods on conditions such as diabetes, cardiovascular disease, obesity, gastrointestinal disorder, cancer and neurodegenerative disorders.

Chondroitin sulfate (CS)-Keel disaccharide (CSD) was produced by chondroitin AC lyase (PsPL8A) degradation of food grade CS-Keel polysaccharide isolated from chicken keel cartilage. PsPL8A showed specific activity, 340 ± 5.2 U mg⁻¹ with CS-Keel polysaccharide. TLC showed CSD as the major product. CSD was purified by gel filtration and MS/MS, confirms it as C4S disaccharide. Structural characterization by FTIR and NMR showed presence of N-acetylgalactosamine and glucuronic acid. CSD displayed resistance to gastric juice with 23.7% hydrolysis at pH 1.0. CSD showed prebiotic score of 0.57 for L. acidophilus and 0.58 for B. infantis and produce SCFA products. MTT and morphological analysis confirmed, CSD (0.5 mg mL⁻¹) does not decrease viability of mouse fibroblast (L929), but showed anti-proliferative potential against human colon cancer (HT-29) cell lines (80% inhibition). CSD treated HT-29 cells exhibit nuclear fragmentation and apoptosis. Prebiotic and anticancer potential of CSD can be utilized for functional food preparation and prevention of gastrointestinal disorders.