Effects of lactokinins from fermented acid goat whey on lipid content and adipogenesis of immortalised human adipocytes

Acid goat whey fermentation by a co-culture of Kluyveromyces marxianus and Lactobacillus rhamnosus yielded a hydrolysate inhibitory for the angiotensin-I-converting enzyme. The potential of this hydrolysate and its main lactokinin tryptophan against accumulation of lipid was investigated at different stages of immortalised human adipocytes development using Oil Red O staining and compared with that of captopril. A slight reduction of lipid content (8%) was observed when mature adipocytes were incubated with the whole hydrolysate at the concentration of 587 μg mL−1. Proliferation of pre-adipocytes was also reduced after incubation with this hydrolysate, which was not cytotoxic. Tryptophan induced a reduction of lipid content of 18% and was cytotoxic towards adipocytes at the concentration found in the hydrolysate: 25.7 μg mL−1. A decrease of the lipid content of mature adipocytes of 28% was observed with 2.9 ng mL−1 of captopril, which was also cytotoxic.