Increase of biological active peptides by proteolytic activity of Oenococcus oeni on the nitrogenous fraction of different cafayate wines varietals

AREDES FERNÁNDEZ, PA; APUD GISSELLE; RODRÍGUEZ VAQUERO, MJ

Mar del Plata

Congreso; VIII Congreso Argentino de Microbiología General; 2012

Sociedad Argentina de Microbiología General (SAMIGE)

Bioactive peptides are specific protein fragments that exhibit specific biological activities. They have a positive impact on body functions or human health. Oenococcus oeni m, beneficial bacterium isolated from Cafayate wines, express a proteolytic system with activity on wine and grape juice proteins. Released peptides could be biological activities. The objective of this work is to investigate the increase of peptides with antihypertensive activity produced by O. oeni m protease on the nitrogenous fraction (NF) isolated from Cafayate wines. Isolation of NF of wine was performed by molecular filtration through 10 KDa filtration membranes. O. oeni m was grown in synthetic wine medium (SWM). Each NF isolated from Cabernet Sauvignon, Malbec, Tannat and Torrontés wine varietals were added into SWM at the same concentration that found in the studied wine varietals, resulting, respectively, the following media: SWCa, SWMa, SWTa, SWTo. At different times, microbial viability (Log ufc/ml); proteins (Bradford), peptides (Doi); proteolytic activity (Doi) and inhibition of angiotensin converting-enzyme (I-ACE activity) were determined. In all media studied, O. oeni m maintained viability for 24 h and then decreases 1 log cycle at 96 h. In SWM (control medium), the proteolytic activity and the nitrogen organic compounds not modifies significantly during incubation. In this condition, I-ACE activity was not detected. In the SWca medium, after 48 h, proteolytic activity detected was 0.67 mmol/L. At this time, a consumption of 695.55 mg N/L of protein nitrogen with an increase of 102.45 mg N/L of peptidic nitrogen was detected. In SWma, an increase of proteolytic activity ( 0.22 mmol/L) was evidenced after 24 h. After this time, protein nitrogen diminishes significantly (332.01 mg N/L), with a peptidic nitrogen release of 99.42 mg N/L. In SWtn a significantly proteolytic activity increase in 1.73 mmol/L was detected after 48 h. At the same time, a maximum consumption of protein nitrogen was detected (329. 26 mg N/L), releasing 231.26 mg N/L of peptidic nitrogen. In SWto the proteolytic activity reaches the maximum value after 24 h (1.05 mmol/L). After this time, the microorganism enables the decrease of protein nitrogen in 433.12 mg N/L with an increase in 255.28 mg N/L in peptide concentration. With respect to I-ACE activity, a significantly increase (65.78%) was detected in SWca at 48h. In SWma this activity reaches the maximum value at 24h (46.42%). In SWtn the higher ACE inhibition was detected at 48h with 69.96%. The activity detected in SWto was maximum at 24h (17.98%). On the basis of these results, we conclude that, the proteolytic activity of O. oeni m in similar conditions to winemaking favors the release of peptides with I-ACE activity, mainly from NF of red wine varietals. These results are the first evidence that O. oeni m could contribute to improving the quality of wine by providing an additional value to the final product.