Biodegradation of phenolic compounds from grape pomace of Vitis vinifera Asyrtiko by Chlamydomonas reinhardtii.

BACKGROUND: Grape pomace from Vitis vinifera Asssyrtiko is an important sub‐product of the Greek wine industry. However, its accumulation is a serious problem with a negative environmental impact. Grape pomace is rich in bioactive compounds and its utilization for alternative uses, such as a fertilizer, is an interesting area of research. On the other hand, its high concentration of phenolic compounds inhibits germination processes. Therefore, there is a need to decrease the high phenolic level in grape pomace before it can be used as a fertilizer. The main objective of our study is the fast reduction of polyphenols in grape pomace, and more specifically catechin and epicatechin in Vitis vinifera Assyrtiko. For this purpose, Chlamydomonas reinhardii was used for polyphenol biodegradation in grape pomace extract. It is shown that the bioremediation proceeds very fast, while the final product has a high potential to be used as a soil conditioner. RESULTS: The results of this study identify that after 6 days of cultivation, C. reinhardtii was able to reduce the total polyphenolic amount by 43%, while catechin and epicatechin were decreased by 100%. In addition, it is shown that the final aqueous product is rich in minerals, such as sodium, phosphorus and potassium. CONCLUSIONS: Through this work we were able to develop a method that allows for the efficient decrease of polyphenols in grape pomace. C. reinhardtii biodegrades a sufficient amount of polyphenols in grape pomace with a high rate, while the product obtained 6 days after cultivation contains high concentrations of minerals and low levels of polyphenols. These results suggest that there is a great potential in using the Vitis vinifera Asssyrtiko biodegraded product as a soil conditioner. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]