Lignocellulolytic Enzymes Production by Four Wild Filamentous Fungi for Olive Stones Valorization: Comparing Three Fermentation Regimens.

Lignocellulolytic enzymes play a crucial role in efficiently converting lignocellulose into valuable platform molecules in various industries. However, they are limited by their production yields, costs, and stability. Consequently, their production by producers adapted to local environments and the choice of low-cost raw materials can address these limitations. Due to the large amounts of olive stones (OS) generated in Morocco which are still undervalued, Penicillium crustosum, Fusarium nygamai, Trichoderma capillare, and Aspergillus calidoustus, are cultivated under different fermentation techniques using this by-product as a local lignocellulosic substrate. Based on a multilevel factorial design, their potential to produce lignocellulolytic enzymes during 15 days of dark incubation was evaluated. The results revealed that P. crustosum expressed a maximum total cellulase activity of 10.9 IU/ml under sequential fermentation (SF) and 3.6 IU/ml of ß-glucosidase activity under submerged fermentation (SmF). F. nygamai recorded the best laccase activity of 9 IU/ml under solid-state fermentation (SSF). Unlike T. capillare, SF was the inducive culture for the former activity with 7.6 IU/ml. A. calidoustus produced, respectively, 1,009 µg/ml of proteins and 11.5 IU/ml of endoglucanase activity as the best results achieved. Optimum cellulase production took place after the 5th day under SF, while ligninases occurred between the 9th and the 11th days under SSF. This study reports for the first time the lignocellulolytic activities of F. nygamai and A. calidoustus. Furthermore, it underlines the potential of the four fungi as biomass decomposers for environmentally-friendly applications, emphasizing the efficiency of OS as an inducing substrate for enzyme production.

Optimizing fungal treatment of lignocellulosic agro-industrial by-products to enhance their nutritional value.

This study delves into the dynamic interaction between various fungal strains, substrates, and treatment durations to optimize the nutritional value of these by-products. Six fungi, including Penicillium chrysogenum, Fusarium sp., Fusarium oxysporum, Fusarium solani, Penicillium crustosum, and Cosmospora viridescens, were evaluated across three substrates: wheat straw (WS), cedar sawdust (CW), and olive pomace (OP) over treatment periods of 4, 8, and 12 weeks. The study discerned profound impacts of these fungi across multiple parameters, including cellulose variation (C.var), lignin variation (L.var), and in vitro true digestibility variation (IVTD.var). Our results demonstrated that the various fungi had a significant effect on all parameters (p < .001). Noteworthy, F. oxysporum and F. solani emerged as exemplars, displaying notable lignin degradation, cellulose liberation, and IVTD enhancement. Importantly, P. crustosum demonstrated substantial cellulose degradation, exhibiting optimal efficacy in just 4 weeks for all substrates. Notably, F. sp. excelled, yielding favorable results when treating WS. P. chrysogenum achieved optimal outcomes with 8-week treatment for WS. Both Fusarium sp. and P. chrysogenum exhibited slight cellulose release, with remarkable reduction of WS lignin compared to other substrates. Especially, WS and OP displayed superior digestibility enhancements relative to CW. It should be noted that the treatment duration further shaped these outcomes, as prolonged treatment (12 weeks) fostered greater benefits in lignin degradation and digestibility, albeit with concomitant cellulose degradation. These findings underscore the intricate balance between fungal strains, substrates, and treatment durations in optimizing the nutritional value of lignocellulosic agro-industrial by-products. The outcomes of this study lead to the enhancement in the overall value of by-products, promoting sustainable livestock feed and advancing agricultural sustainability.

In silico comparative genomic analysis unravels a new candidate protein arsenal specifically associated with Fusarium oxysporum f. sp. albedinis pathogenesis.

Fusarium oxysporum f. sp albedinis (Foa) is a devastating fungus of date palms. To unravel the genetic characteristics associated with its pathogenesis, the two available genomes of Foa 133 and Foa 9 were compared with 49 genomes of 29 other pathogenic formae speciales belonging to Fusarium oxysporum species complex (FOSC). Foa 133 and Foa 9 have genomes of 56.23 Mb and 65.56 Mb with 17460 and 19514 putative coding genes. Of these genes, 30% lack functional annotation with no similarity to characterized proteins. The remaining genes were involved in pathways essential to the fungi's life and their adaptation. Foa secretome analysis revealed that both Foa strains possess an expanded number of secreted effectors (3003 in Foa 133 and 2418 in Foa 9). Those include effectors encoded by Foa unique genes that are involved in Foa penetration (Egh16-like family), host defense mechanisms suppression (lysM family) and pathogen protection (cysteine-rich protein family). The accessory protein SIX6, which induces plant cell death, was also predicted in Foa. Further analysis of secreted CAZymes revealed an arsenal of enzymes involved in plant cell wall degradation. This arsenal includes an exclusively Foa-specific CAZyme (GH5-7). Transcription factors and membrane transporters (MFS) involved in fungicide efflux have been predicted in Foa, in addition to a variety of secondary metabolites. These comprise mycotoxins as well as chrysogin, the latter provides Foa with resistance against adverse environmental conditions. Our results revealed new Foa proteins that could be targeted in future research in order to manage Bayoud disease.

Phenolic compounds, in vivo anti-inflammatory, analgesic and antipyretic activities of the aqueous extracts from fresh and dry aerial parts of Brocchia cinerea (Vis.).

Aerial parts of Brocchia cinerea (Vis.) (Asteraceae family) are traditionally used for the treatment of pain, fever and inflammation. The present study aimed to investigate the phenolic profile, the acute oral toxicity, and anti-inflammatory, analgesic and antipyretic activities of the aqueous extracts from fresh (FBC) and dry (DBC) aerial parts of Brocchia cinerea (Vis.). Phenolic profile from FBC and DBC was characterized by HPLC-PDA/ESI-MS. The anti-inflammatory, analgesic and antipyretic of both FBC and DBC were evaluated by carrageenan induced paw edema, acetic acid induced writhing and brewer's yeast-induced pyrexia in Wistar rats, respectively. The results achieved showed that thirteen phenolic compounds were detected in the aqueous extracts obtained from the aerial parts of FBC and DBC, highlighting a quite different quantitative profile. The FBC and DBC administrated orally at a dose of 400 mg/kg significantly reduced edema, after 2 h of the injection of carrageenan (p < 0.001) with a percentage inhibition of 47.73% and 50.01% respectively. On the other hand the rats treated with DBC at the same dose significantly lowered the writhing induced by the injection of acetic acid (18.52 ± 0.38) with respect to the ones treated with FBC (20.47 ± 0.92). Moreover, a significant reduction in rectal temperature was observed in rats treated with FBC/DBC and at doses of 200 and 400 mg/kg. Furthermore, no acute toxicity symptoms were observed on oral administration of all doses of both FBC and DBC in Wistar rats. The results of the present study indicate that the aerial part of Brocchia cinerea extracts exhibit strongly anti-inflammatory, analgesic, and antipyretic properties and they can be potentially used in the treatment of inflammation, pain and fever.

Genotyping study of Scedosporium apiospermum isolates from patients with cystic fibrosis.

Usually a saprophyte, Scedosporium apiospermum often colonizes the respiratory tracts of patients with cystic fibrosis (CF). In order to improve our understanding of the molecular epidemiology of the airway colonization, 129 sequential and multiple isolates collected from January 1998 to March 1999 from nine CF patients monitored in three hospitals in France were typed by random amplification of polymorphic DNA with primers GC70, UBC-701, and UBC-703. Among these primers, UBC-703 was the most discriminating, allowing the differentiation of 14 genotypes. Combining the results obtained with this three-primer set resulted in the differentiation of 16 genotypes. No common genotype was found among the different patients, and no clustering according to geographic origin of the isolates was seen. In addition, five of the patients were colonized by a single genotype. The others usually exhibited a predominant genotype accompanied by one or two others, which were found occasionally and were genetically close to the predominant genotype. Thus, our study demonstrates the persistence of the fungus despite antifungal treatments and therefore reinforces the need for the development of new antifungals that are more efficient against this species.