Sustainable and Eco-Friendly Conversions of Olive Mill Wastewater-Based Media by Pleurotus pulmonarius Cultures

Abstract

Pleurotus pulmonarius mushroom was cultivated on liquid cultures with olive mill wastewaters (OMWs) of initial phenolic compound concentrations of 0 (control), 1, 2 and 3 g/L and glucose at initial concentrations of 40 and 60 g/L. The ability of the fungus to grow on media containing toxic compounds enriched with glucose was assessed through biomass production, glucose consumption, polysaccharide (IPS) accumulation and total cellular lipids biosynthesis, while the total phenolic compounds (TPC) and antioxidant component monitoring were also assessed during a 43-day fermentation. An analysis of the total simple sugar composition of IPS and the total fatty acid composition of lipids was performed. The phenolic reduction and media decolorization were also monitored. Results showed that the addition of glucose in OMW-based media had a positive effect on biomass, IPS and lipid production and increased the unsaturated fatty acids and TPC concentration. The maximum recorded values were the following: biomass 32.76 g/L, IPS 4.38 g/L (14.70%, w/w in dry weight), lipids 2.85 g/L (11.69%, w/w in dry weight). The mycelial lipids were unsaturated and dominated by linoleic acid, whereas IPS were composed mainly of glucose. Significant phenolic compound reduction (87–95%) and color removal (70–85%) occurred. Results strongly suggest the potentiality of P. pulmonarius utilization in the OMW treatment.

Laccase and Biomass Production via Submerged Cultivation of Pleurotus ostreatus Using Wine Lees

“…Our study presents a higher dephenolization rate, and from a study of P. ostreatus using grape pomace as a substrate, its value reached only 68%, while the laccase production maximum value was 4447 U/g of substrate, and the biomass reached a value of 0.42 ± 0.01 g/g substrate [42]. Our values for dephenolization and decolorization were close to that published by Diamantis et al for Pleurotus pulmonarius in Olive mill wastewater, with the observed values ranging from 87% to 95% for dephenolization and from 70% to 85% for decolorization [43]. Focusing on laccase production, our study revealed higher laccase production levels in comparison with other studies for Pleurotus ostreatus involving cultivation on 20 g/L tomato pomace and 1 g/L ammonium sulfate (0.147 Units/mL), cultivation on 20 g/L glucose and 5 g/L peanut shell (5 Units/mL), cultivation on 20 g/L glucose and 5 g/L bagasse (15 Units/mL), cultivation on 20 g/L glucose and 5 g/L tea leaflets (30 Units/mL), and cultivation on 20 g/L glucose and 5 g/L orange peel (45 Units/mL) [14,44].…”

Valorization of Agro-Industrial Wastes and Residues through the Production of Bioactive Compounds by Macrofungi in Liquid State Cultures: Growing Circular Economy

“…The metabolism of many macrofungi has been studied in synthetic media with various carbon and nitrogen sources to determine growth patterns and their productivity [21,22]. Current research indicates that satisfying quantities of macrofungi mycelial biomass can be produced in liquid cultures using agro-industrial side-streams as the sole carbon source [23][24][25][26][27]. Submerged cultivation of macrofungi is an efficient, reproducible, and potentially scalable method to produce fungal biomass and metabolites (Figure 1).…”

Growth Response of Non-Conventional Yeasts on Sugar-Rich Media: Part 2: Citric Acid Production and Circular-Oriented Valorization of Glucose-Enriched Olive Mill Wastewaters Using Novel Yarrowia lipolytica Strains

“…Recent developments in the research related to the biotechnological valorization of OMWs indicate that these liquid streams should be considered as a fermentation medium to valorize rather than a waste to discharge, being as both a process water and a potential liquid substrate for various fermentation processes [ 11 , 20 , 21 , 22 , 23 ]. In several cases, OMWs have been employed to “dilute” “concentrated” residues and waste streams like molasses and crude glycerol [ 14 , 24 , 25 ].…”

“…In several cases, OMWs have been employed to “dilute” “concentrated” residues and waste streams like molasses and crude glycerol [ 14 , 24 , 25 ]. It is evident that a prerequisite for the successful accomplishment of the mentioned bioprocess would be that the implicated microorganisms would withstand the (potentially elevated concentrations of the) phenolic compounds found in the OMW-based media [ 14 , 18 , 20 , 21 , 23 , 24 , 26 ] while of significant interest, would be the simultaneous detoxification ( viz . dephenolization and decolorization) of the OMW-based media, together with the production of added-value metabolites [ 14 , 18 , 23 , 24 , 26 ].…”