Processing Wastewaters from Spanish-Style cv. Chalkidiki Green Olives: A Potential Source of Enterococcus casseliflavus and Hydroxytyrosol

Abstract

The purpose of this study was to examine the isolation of indigenous lactic acid bacteria (LAB) with functional properties from Spanish-style cv. Chalkidiki green olive processing wastewaters (GOW). Predominant indigenous LAB could serve as bioaugmentation agents/starter culture for table olives production and protected designation of origin specification. Spontaneous fermentation of fresh GOW over different temperatures (15 °C to 50 °C) and pH values (3.5 to 11.5) for 30 d enabled the isolation/molecular identification of the lactic acid bacterium Enterococcus casseliflavus and the plant-associated bacterium Bacillus amyloliquefaciens subsp. plantarum. E. casseliflavus was found to reduce chemical oxygen demand by 72%. Its resistance to extreme pH values, salinity, and temperature was successfully modeled and the minimum inhibitory concentration of oleuropein against the bacterial growth was determined (0.9 g/L). Furthermore, hydroxytyrosol content was doubled (up to 553 mg/L) after GOW spontaneous fermentation under acidic conditions at 15 °C to 30 °C for 120 d, creating an additional source of input. These results highlight the significance and potential of E. casseliflavus in Spanish-style cv. Chalkidiki green olive processing.

Probiotic potentials of the silkworm gut symbiont Enterococcus casseliflavus ECB140, a promising L-tryptophan producer living inside the host

“…Notably, ECB140 contains vancomycin resistance genes, vanC and vanT (EMB140PGM001036, EMB140PGM001037 and EMB140PGM001039), which confer low‐level intrinsic resistance to vancomycin for Ent. casseliflavus (Berktas et al, 2008; Papadaki et al, 2020; Park et al, 1997).…”

Natural β-Carotene Production by Blakeslea trispora Cultivated in Spanish-Style Green Olive Processing Wastewaters

“…Among the organic molecules existing in lye and washing waters, particular attention should be given to the phenolic compounds because the latter are related to the streams phytotoxic properties and are not easily biodegradable [ 26 ]. On the other hand, the prospect of recovering hydroxytyrosol and tyrosol, two high-value compounds with a wide spectrum of biological activities toward human health protection, seems an interesting alternative [ 37 , 38 , 39 ]. Thus, it was considered useful to evaluate the ability of B. trispora to metabolize the respective molecules.…”