Combined bioremediation and enzyme production by Aspergillus sp. in olive mill and winery wastewaters

Olive mill wastewaters (OMW) and vinasses (VS) are effluents produced respectively by olive mills and wineries, both sectors are of great economic importance in Mediterranean countries. These effluents cause a large environmental impact, when not properly processed, due to their high concentration of phenolic compounds, COD and colour. OMW may be treated by biological processes but, in this case, a dilution is necessary, increasing water consumption. The approach here in proposed consists on the bioremediation of OMW and VS by filamentous fungi. In a screening stage, three fungi (Aspergillus ibericus, Aspergillus uvarum, Aspergillus niger) were selected to bioremediate undiluted OMW, two-fold diluted OMW supplemented with nutrients, and a mixture of OMW and VS in the proportion 1:1 (v/v). Higher reductions of phenolic compounds, colour and COD were achieved mixing both residues; with A. uvarum providing the best results. In addition, the production of enzymes was also evaluated during this bioremediation process, detecting in all cases lipolytic, proteolytic and tannase activities. A. ibericus, A. uvarum and A. niger achieved the highest value of lipase (1253.7 ± 161.2 U/L), protease (3700 ± 124.3 U/L) and tannase (284.4 ± 12.1 U/L) activities, respectively. Consequently, this process is an interesting alternative to traditional processes to manage these residues, providing simultaneously high economic products, which can be employed in the same industries.Supported by the grant SFRH/BPD/84440/2012 and SFRH/BPD/43922/2008 respectively, from Fundação para a Ciência e Tecnologia – FCT, Portugal. Fundação para a Ciência e a Tecnologia (FCT) for financial support through the project FCT Pest-OE/EQB/LA0023/2011. Also, authors thank the Project “BioInd – Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028” Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDE

Biodegradation of olive washing wastewater pollutants by highly efficient phenol-degrading strains selected from adapted bacterial community

The bacterial community of an olive washing water (OWW) storage basin was characterized, by both cultivation and cultivation-independent methods. PCR-TGGE fingerprints analysis of different samples, taken along the olive harvesting season, revealed important variations of the bacterial community structure showing rapid establishment of prevalent bacterial populations. Several bacteria, isolated from OWW, were cultivated, in media containing increasing amounts of polyphenols, in order to select high phenol-degrading strains for the effluent pollutants reduction. Strains PM3 and PM15, affiliated to Raoultella terrigena and Pantoea agglomerans by 16S rRNA gene sequencing, were selected and used for OWW biological treatment under batch conditions in shake flasks cultures. The OWW content of phenols, BOD5, COD and colour, was reduced by 93, 91, 89 and 62%, respectively, permitting effluent disposal and/or reuse with no additional treatments.This research was supported by European project Algatec (FP7/SME/2008/1/232331)

Culture du Lentinula edodes (Berk.) Peglersur résidus oléicoles en fermentation en milieu solide : transformation des polyphénols des margines

L'objectif du travail a été d'étudier la valorisation de sous-produits oléicoles au Maroc par la culture en fermentation en milieu solide de champignons comestibles avec une double finalité : (i) la production de la biomasse fongique pour l'alimentation humaine et (ii) la détoxification des margines par la dégradation des composés phénoliques. A partir de seize souches de L. edodes, une souche performante à la détoxification des margines a été sélectionnée pour mener la culture de L. edodes. La production de l'inoculum sur les grains de blé (spawn) a été optimisée. Un mélange des substrats oléicoles solides (SOS), composé de bois de taille d'olivier, de grignons d'olive et de margines, a été mis au point et les conditions de croissance de L. edodes sur ce mélange ont été optimisées. Le changement de la matière organique durant le développement de L. edodes sur le mélange dans des conditions optimales a été analysé par les techniques spectroscopiques de la RMN solide du 13C couplées aux analyses biochimiques. Une technique de séchage solaire sous serre a été mise au point permettant la réduction en volume et le conditionnement des grignons d'olives mélangés aux margines. De ce travail, nous concluons la possibilité de valoriser l'ensemble des co-produits de l'industrie oléicole par la culture de L. edodes permettant, d'une part, la production d'une biomasse mycélienne importante et, d'autre part, la dégradation des composés phénoliques présents dans les margines. Ces résultats novateurs ouvrent des perspectives sérieuses pour la production de L. edodes sur le SOS.AIX-MARSEILLE3-BU Sc.St Jérô (130552102) / SudocSudocFranceF

Screening of strains of Lentinula edodes grown on model olive mill wastewater in solid and liquid state culture for polyphenol biodegradation

In Morocco, the olive industry produces great amounts of olive mill wastewater (OMW) yearly in a short period (250 000 m(3) of liquid wastes in four months, November-February). Phenolic compounds are largely responsible for the phytotoxicity and antimicrobial effects of OMW. Several studies have been carried out on biological and enzymatic treatments of OMW. However, the use of OMW to produce value-added products, e.g. mushroom cultivation, are less explored. This research aimed to select shiitake mushroom strains capable of growing on OMW, involving decolorization, removal of total phenol, and high production of mycelial biomass. Sixteen strains of Lentinula edodes were evaluated for their tolerance to OMW, apical growth rate, and biomass production on agar media. The highest biomass yields were recorded in four strains (Le118, Le119, Le121, Le122) grown in the presence of 20% (v/v) OMW. The ability of these pre-selected strains to decolorize and to remove total phenol from OMW was then assessed in liquid culture, without nutritional supplements. The strain Le119 of L edodes showed 65% decolorization, and 75% elimination of total phenol according to the Folin-Ciocalteu assay. Laccase production was the main lignolytic activity observed, and one of its isoforms stained on native PAGE with p-phenylenediamine as substrate at pH 5.0

Effect of acclimatization on earthworm's (Eisenia andrei) potential on olive mille wastewaters detoxification

Proceedings of Euro-Mediterranean Conference for Environmental Integration (EMCEI-1), Tunisia 2017International audienceA laboratory vermicomposting (two months duration) was conducted to evaluate the effect of earthworm acclimatization (epigeic—Eisenia andrei) on decomposition and detoxification of olive mill wastewaters. The Earthworm growth rate and phenols reduction were superior in the mixture with acclimated earthworms (21.83 ± 0.01 mg worm−1 day−1 and 72% respectively), than mixture with unacclimated earthworms (4.67 ± 0.01 mg worm−1 day−1 and 41% respectively). The data reveal that acclimatization of earthworms is a promising alternative for OMWW detoxification and vermicomposting (using E. andrei) is a suitable technology for olive by-products conversion into value-added materials