Cardiovascular Effects of Whey from Prozyme 6-Facilitated Lactic Acid Bacteris Fermentation of Milk

• Published in: Journal of food biochemistry 2007-10, Vol.31 (5), p.639-655
• Main Authors: Chen, Guan-Wen, Tsai, Jenn-Shou, Pan, Bonnie Sun
• Format: Article
• Language: English
• Subjects: Bacteria
• ISSN: 0145-8884; 1745-4514
• DOI: 10.1111/j.1745-4514.2007.00135.x

Fresh low-fat milk was fermented for up to 30 h at 42C with five mixed lactic acid bacteria. A protease, Prozyme 6, was added 5 h after the beginning of bacterial fermentation. The whey was separated from the fermented milk and freeze-dried. As the fermentation time extended to 30 h, the inhibition of lipoxygenase increased as indicated by a decrease of IC sub(50) from 3.79 to 0.47 mg powder-mL. The relative percentage of binding bile acid by whey was 39.3% in comparison to cholestyramine. Inhibition of angiotensin I-converting enzyme increased as shown by a decrease of IC sub(50) from 1.18 to 0.24 mg powder-mL. The systolic blood pressure and diastolic blood pressure were reduced 22.6 and 21.5 mmHg, respectively, in spontaneously hypertensive rat, after 8 weeks of oral administration of diluted whey (12.5 mg powder-mL). A new technique was developed in this experiment using a combination of lactic acid bacteria fermentation and protease hydrolysis to accelerate the production of bioactive peptides from fresh low-fat milk. The fermented whey product exhibited in vitro inhibition on lipoxygenase (LOX) and angiotensin I-converting enzyme, and reduced the LOX-catalyzed low-density lipoprotein oxidation. The whey product also showed higher bile acid binding capacity; thus, it might possibly have the potential of reducing serum cholesterol in vivo. Also, in vivo antihypertensive effect was confirmed on spontaneouosly hypertensive rat by long- or short-term administration. This fermented milk whey was expected to be a useful ingredient in physiologically functional foods for reduction of cardiovascular disease risk.