Fusarium species—a promising tool box for industrial biotechnology

The bioherbicidal potential of isolated fungi cultivated in microalgal biomass

This study evaluated the bioherbicidal potential of wild fungi grown on microalgal biomass from the digestate treatment of biogas production. Four fungal isolates were used and the extracts were evaluated for the activity of different enzymes and characterized by gas chromatography coupled with mass spectrometry. The bioherbicidal activity was assessed by application on Cucumis sativus, and the leaf damage was visually estimated. The microorganisms showed potential as agents producing an enzyme pool. The obtained fungal extracts presented different organic compounds, most acids, and when applied to Cucumis sativus, showed high levels of leaf damage (80-100 ± 3.00%, deviation relative to the observed average damage). Therefore, the microbial strains are potential biological control agents of weeds, which, together with the microalgae biomass, offer the appropriate conditions to obtain an enzyme pool of biotechnological relevance and with favorable characteristics to be explored as bioherbicides, addressing aspects within the environmental sustainability.

Fusarium spp. associated with Chenopodium quinoa crops in Colombia

Quinoa is a plant commonly-resistance to adverse biotic and abiotic factors. However, this crop can be affected by phytopathogenic fungi. There is a lack of knowledge about the fungi associated with quinoa plants in Colombia. Through morphological and molecular identification in this study were identified four Fusarium species associated with quinoa crops: Fusarium oxysporum, Fusarium graminearum, Fusarium equiseti, and Fusarium culmorum. For this, we collected samples of panicles, leaf tissue, root tissue, and soil for isolation of different isolates of Fusarium. We performed a pathogenicity test of the fungi strains, under greenhouse conditions to evaluate the pathogenicity in seedlings of the Piartal cultivar with two inoculation methods. First inoculating the stem through a nodal wound or second inoculating the abaxial face with a brush. The results indicate the presence of four species with both molecular markers, phylogenetically distributed in these groups. The four species turned out to be pathogenic but with different degrees of virulence with significant differences between F. graminearum and F. oxysporum depending on the inoculation method. This is the first report on the presence of Fusarium species isolated from Quinoa in Colombia.

Genome mining of Fusarium reveals structural and functional diversity of pectin lyases: a bioinformatics approach

Pectin lyase (PNL) is an important enzyme of the pectinases group which degrades pectin polymer to 4,5-unsaturated oligogalacturonides by a unique β-elimination mechanism and is used in several industries. The existence of multigene families of pectin lyases has been investigated by mining microbial genomes. In the present study, 52 pectin lyase genes were predicted from sequenced six species of Fusarium, namely F. fujikuroi, F. graminearum, F. proliferatum, F. oxysporum, F. verticillioides and F. virguliforme. These sequences were in silico characterized for several physico-chemical, structural and functional attributes. The translated PNL proteins showed variability with 344-1142 amino acid residues, 35.44-127.41 kDa molecular weight, and pI ranging from 4.63 to 9.28. The aliphatic index ranged from 75.33 to 84.75. Multiple sequence alignment analysis showed several conserved amino acid residues and five distinct groups marked as I, II, III, IV, and V were observed in the phylogenetic tree. The Three-dimensional Structure of five of these PNLs, each representing a distinct group of phylogenetic trees was predicted using I-TASSER Server and validated. The pectin lyase proteins of Fusarium species revealed close similarity with pectin lyase of Aspergillus niger PelA(1IDJ) and PelB(1QCX). Diversity in the structural motifs was observed among Fusarium species with 2 β-sheets, 1 β-hairpin, 7-12 β bulges, 18-25 strands, 6 -11 helices, 1 helix-helix interaction, 32-49 β turns, 2-6 γ turns and 2- 3 disulfide bonds. The unique Pec_lyase domain was uniformly observed among all PNL proteins confirming its identity. The genome-wide mining of Fusarium species was attempted to provide the diversity of PNL genes, which could be explored for diverse applications after performing cloning and expression studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03333-w.

Trends and challenges in phytotherapy and phytocosmetics for skin aging

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Free radicals, oxidative stress, and inflammation contribute to the etiology of most chronic diseases.

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Natural products can be incorporated into cosmetics, cosmeceuticals, and nutricosmetics to tackle inflammation-related diseases.

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The use of alternative green extraction solvents such as natural deep eutectic solvents and electrochemically reduced water is trending.

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Delivery systems are important for the enhancement of the bioavailability, stability, solubility, and controlled release profile of the bioactives.

Oxidative stress and inflammation mostly contribute to aging and age-related conditions including skin aging. The potential of natural products in the form of naturally-derived cosmetics, cosmeceuticals, and nutricosmetics have, however, not been fully harnessed. This review, thus, critically analyzes the potential roles of natural products in inflammation-related skin aging diseases due to the increasing consumers’ concerns and demands for efficacious, safe, natural, sustainable, and religiously permitted alternatives to synthetic products. The information and data were collated from various resources and literature databases such as PubMed, Science Direct, Wiley, Springer, Taylor and Francis, Scopus, Inflibnet, Google, and Google Scholar using relevant keywords and Medical Subject Headings (MeSH). The role of green extraction solvents as promising alternatives is also elucidated. The potential enhancements of the bioavailability, stability, solubility and controlled release profile of the bioactives using different delivery systems are also presented. The current potential global market value, motivators, drivers, trends, challenges, halal, and other regulatory certifications for cosmeceuticals and nutricosmetics are equally discussed. The adoption of the suggested extractions and delivery systems would enhance the stability, bioavailability, and target delivery of the bioactives.

Life in the Wheat Litter: Effects of Future Climate on Microbiome and Function During the Early Phase of Decomposition

Even though it is widely acknowledged that litter decomposition can be impacted by climate change, the functional roles of microbes involved in the decomposition and their answer to climate change are less understood. This study used a field experimental facility settled in Central Germany to analyze the effects of ambient vs. future climate that is expected in 50-80 years on mass loss and physicochemical parameters of wheat litter in agricultural cropland at the early phase of litter decomposition process. Additionally, the effects of climate change were assessed on microbial richness, community compositions, interactions, and their functions (production of extracellular enzymes), as well as litter physicochemical factors shaping their colonization. The initial physicochemical properties of wheat litter did not change between both climate conditions; however, future climate significantly accelerated litter mass loss as compared with ambient one. Using MiSeq Illumina sequencing, we found that future climate significantly increased fungal richness and altered fungal communities over time, while bacterial communities were more resistant in wheat residues. Changes on fungal richness and/or community composition corresponded to different physicochemical factors of litter under ambient (Ca²⁺, and pH) and future (C/N, N, P, K⁺, Ca²⁺, pH, and moisture) climate conditions. Moreover, highly correlative interactions between richness of bacteria and fungi were detected under future climate. Furthermore, the co-occurrence networks patterns among dominant microorganisms inhabiting wheat residues were strongly distinct between future and ambient climates. Activities of microbial β-glucosidase and N-acetylglucosaminidase in wheat litter were increased over time. Such increased enzymatic activities were coupled with a significant positive correlation between microbial (both bacteria and fungi) richness and community compositions with these two enzymatic activities only under future climate. Overall, we provide evidence that future climate significantly impacted the early phase of wheat litter decomposition through direct effects on fungal communities and through indirect effects on microbial interactions as well as corresponding enzyme production.

α-Glucosidase inhibitory effect of an anthraquinonoid produced by Fusarium incarnatum GDZZ-G2

α-Glucosidase is the key enzyme on carbohydrate metabolism, and its bioactive inhibitors are supposed to be an effective therapeutic for type 2 diabetes mellitus. During our continuing study for discovering α-glucosidase inhibitors, a fungus GDZZ-G2 which is derived from a medicinal plant Callicarpa kwangtungensis Chun, exhibited significant inhibition on α-glucosidase. The strain was identified as Fusarium incarnatum by morphological and molecular methods. Further bioassay-guided fractionation result in six known secondary metabolites (1-6). All the compounds except 4 were isolated from F. incarnatum for the first time. Among them, an anthraquinonoid (S)-1,3,6-trihydroxy-7-(1-hydroxyethyl)anthracene-9,10-dione (compound 1) exhibited strong inhibitory effect against α-glucosidase (IC₅₀  = 77.67 ± 0.67 μΜ), compared with acarbose (IC₅₀  = 711.8 ± 5 μΜ). An enzyme kinetics analysis revealed that compound 1 was an uncompetitive inhibitor. Besides, docking simulations predicted that compound 1 inhibited α-glucosidase substrate complex by binding Gln322, Gly306, Thr307, and Ser329 through hydrogen-bond interactions. Our findings suggested that compound 1 can be considered a lead compound for further modifications and the development of a new effective drug candidate in the treatment of type 2 diabetes mellitus.

Enzymatic Bioprospecting of Fungi Isolated from a Tropical Rainforest in Mexico

The humid tropical environment provides an ideal place for developing a high diversity of plants; this is why it is an interesting site for the enzymatic bioprospecting of fungi that are responsible for the recycling of organic matter in an efficient and accelerated way and whose enzymes could have multiple biotechnological applications. For this study, 1250 isolates of macroscopic and microscopic fungal morphotypes were collected from soil, leaf litter, and wood. One hundred and fifty strains (50 from each source) were selected for the enzymatic screening. From the first phase, 51 strains with positive activity for laccase, protease, amylase, xylanase, and lipase enzymes were evaluated, of which 20 were isolated from leaf litter, 18 from the soil, and 13 from wood. The 10 best strains were selected for the enzymatic quantification, considering the potency index and the production of at least two enzymes. High laccase activity was detected for Trametes villosa FE35 and Marasmius sp. CE25 (1179 and 710.66 U/mg, respectively), while Daedalea flavida PE47 showed laccase (521.85 U/mg) and protease activities (80.66 U/mg). Fusarium spp. PH79 and FS400 strains had amylase (14.0 U/mg, 49.23 U/mg) and xylanase activities (40.05 U/mg, 36.03 U/mg) respectively. These results confirm the enzymatic potential of fungi that inhabit little-explored tropical rainforests with applications in industry.

Filamentous fungal applications in biotechnology: a combined bibliometric and patentometric assessment

BACKGROUND

Processes and products employing filamentous fungi are increasing contributors to biotechnology. These organisms are used as cell factories for the synthesis of platform chemicals, enzymes, acids, foodstuffs and therapeutics. More recent applications include processing biomass into construction or textile materials. These exciting advances raise several interrelated questions regarding the contributions of filamentous fungi to biotechnology. For example, are advances in this discipline a major contributor compared to other organisms, e.g. plants or bacteria? From a geographical perspective, where is this work conducted? Which species are predominantly used? How do biotech companies actually use these organisms?

RESULTS

To glean a snapshot of the state of the discipline, literature (bibliometry) and patent (patentometry) outputs of filamentous fungal applications and the related fields were quantitatively surveyed. How these outputs vary across fungal species, industrial application(s), geographical locations and biotechnological companies were analysed. Results identified (i) fungi as crucial drivers for publications and patents in biotechnology, (ii) enzyme and organic acid production as the main applications, (iii) Aspergillus as the most commonly used genus by biotechnologists, (iv) China, the United States, Brazil, and Europe as the leaders in filamentous fungal science, and (v) the key players in industrial biotechnology.

CONCLUSIONS

This study generated a summary of the status of filamentous fungal applications in biotechnology. Both bibliometric and patentometric data have identified several key trends, breakthroughs and challenges faced by the fungal research community. The analysis suggests that the future is bright for filamentous fungal research worldwide.

Strategies to meet the global demand for natural food colorant bixin: A multidisciplinary approach

Bixin is an apocarotenoid derived from Bixa orellana L. well known as a food colorant along with its numerous industrial and therapeutic applications. With the current surge in usage of natural products, bixin has contributed immensely to the world carotenoid market and showcases a spike in its requirement globally. To bridge the gap between bixin availability and utility, owed to its bioactivity and demand as a colouring agent in industries the sustainable production of bixin is critical. Therefore, to meet up this challenge effective use of multidisciplinary strategies is a promising choice to enhance bixin quantity and quality. Here we report, an optimal blend of approaches directed towards manipulation of bixin biosynthesis pathway with an insight into the impact of regulatory mechanisms and environmental dynamics, engineering carotenoid degradation in plants other than annatto, usage of tissue culture techniques supported with diverse elicitations, molecular breeding, application of in silico predictive tools, screening of microbial bio-factories as alternatives, preservation of bixin bioavailability, and promotion of eco-friendly extraction techniques to play a collaborative role in promoting sustainable bixin production.

Total Synthesis and Structure Revision of a Fungal Glycolipid Fusaroside

Herein, we report a strategy for the total synthesis of a structurally unique fungal glycolipid fusaroside. The first total synthesis of the proposed structure involved construction of the complex, branched lipid chain having a variety of alkenes with E stereochemistry and attachment of the masked α,β-unsaturated β-keto acid at the O-4 position of trehalose as key steps. We propose a revision in the structure of fusaroside, particularly the position of olefins in the lipid chain.

Biocatalytic Transformation of 5-Hydroxymethylfurfural into 2,5-di(hydroxymethyl)furan by a Newly Isolated Fusarium striatum Strain

The compound 2,5-di(hydroxymethyl)furan (DHMF) is a high-value chemical block that can be synthesized from 5-hydroxymethylfurfural (HMF), a platform chemical that results from the dehydration of biomass-derived carbohydrates. In this work, the HMF biotransformation capability of different Fusarium species was evaluated, and F. striatum was selected to produce DHMF. The effects of the inoculum size, glucose concentration and pH of the media over DHMF production were evaluated by a 23 factorial design. A substrate feeding approach was found suitable to overcome the toxicity effect of HMF towards the cells when added at high concentrations (>75 mM). The process was successfully scaled-up at bioreactor scale (1.3 L working volume) with excellent DHMF production yields (95%) and selectivity (98%). DHMF was purified from the reaction media with high recovery and purity by organic solvent extraction with ethyl acetate.

Mycosynthesis of novel lactone in foliar endophytic fungus isolated from Bixa orellana L

There is a colossal demand for natural pigments and its applications in recent times. In the study, a novel lactone pigment was isolated from a predominant endophytic fungus residing in Bixa orellana L. (Bixaceae) leaves. The endophyte was identified as Fusarium verticillioides through morphological and molecular investigations. The optimum growth parameters of the endophyte for pigment production were at 33 ºC with pH 6.5 in dark. Through comprehensive spectroscopic studies, the structure of the isolated lactone was resolved and identified as (E)-3, 3-dimethyl-4-(pent-1-en-1-yl)-4-propyldihydrofuran-2(3H)-one. The acute oral toxicity study of the pigment investigated upon female Wistar rats indicated the median lethal dose (LD₅₀) value above 1000 mg/kg body weight affirming safety. Thus, the red pigment from the isolated endophyte may be employed as a sustainable source for natural colorant in industries owing to its non-toxicity.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-020-02566-x.

Production and characterization of an enzyme extract with cellulase activity produced by an indigenous strain of Fusarium verticillioides ITV03 using sweet sorghum bagasse

OBJECTIVES

To evaluate a strain of Fusarium verticillioides ITV03 isolated from wood residues in the Veracruz region of Mexico. Endoglucanase and β-glucosidase production by submerged fermentation was optimized using a Box-Behnken design, where the independent variables were urea, ammonium sulfate and yeast extract.

RESULTS

After optimization, an endoglucanase activity of 0.27 U/mL was achieved; subsequently, three carbon sources were evaluated (carboxymethyl cellulose, sweet sorghum bagasse cellulose and delignified sweet sorghum bagasse (DSSB). The results showed that DSSB yielded the greatest endoglucanase (0.28 U/mL) and β-glucosidase (0.12 U/mL) activities. Both enzymatic activities were characterized for the effect of pH, temperature and thermostability. The optimal parameters of β-glucosidase and endoglucanase activity were pH 5 and 4 respectively, the optimum temperature 60 °C. These enzymes were stable at 50 °C for 150.68 h and 8.54 h, with an activation energy (E_a(day)) of 265.55 kJ/mol and 44.40 kJ/mol respectively, for β-glucosidase and endoglucanase.

CONCLUSION

The present work shows that a native strain like F. verticillioides ITV03 using DSSB supplemented with nitrogen has a great potential as a producer of cellulase for lignocellulosic residue hydrolysis.

Analysis of Fungal Composition in Mine-Contaminated Soils in Hechi City

Fungi play an important role in bioremediation of contaminated soil. However, the diversity of fungal populations in four mine-contaminated soils located in Hechi City has remained unexplored. In this study, high-throughput sequencing of ITS was performed to investigate the diversity and abundance of fungal communities in four mine-contaminated soils in Hechi city. Phylogenetic taxonomy showed that the fungal communities included five phyla. Ascomycota and Basidiomycota were the most abundant phyla in four samples. The most abundant fungi included Agaricomycetes, Nectriaceae, Eurotiomycetes, Mortierellaceae, Incertae sedis, Trichocomaceae, Sordariomycetes, and Fusarium. Various fungi with the potential of bioremediation and industrial application were discussed. The results of fungal composition will provide a clue for isolation of new fungi with the potential of bioremediation and industrial application. Furthermore, this study will lay a good foundation for modifying the indigenous fungi by genetic engineering in the future.

Putative metabolic pathway for the bioproduction of bikaverin and intermediates thereof in the wild Fusarium oxysporum LCP531 strain

Fungal naphthoquinones, like red bikaverin, are of interest due to their growing applications in designing pharmaceutical products. Though considerable work has been done on the elucidation of bikaverin biosynthesis pathway in Fusarium fujikuroi, very few reports are available regarding its bioproduction in F. oxysporum. We are hereby proposing a putative metabolic pathway for bikaverin bioproduction in a wild F. oxysporum strain by cross-linking the pigment profiles we obtained under two different fermentation conditions with literature. Naphthoquinone pigments were extracted with a pressurized liquid extraction method, and characterized by HPLC–DAD and UHPLC-HRMS. The results led to the conclusions that the F. oxysporum LCP531 strain was able to produce bikaverin and its various intermediates, e.g., pre-bikaverin, oxo-pre-bikaverin, dinor-bikaverin, me-oxo-pre-bikaverin, and nor-bikaverin, in submerged cultures in various proportions. To our knowledge, this is the first report of the isolation of these five bikaverin intermediates from F. oxysporum cultures, providing us with steady clues for confirming a bikaverin metabolic pathway as well as some of its regulatory patterns in the F. oxysporum LCP531 strain, based on the previously reported model in F. fujikuroi. Interestingly, norbikaverin accumulated along with bikaverin in mycelial cells when the strain grew on simple carbon and nitrogen sources and additional cofactors. Along bikaverin production, we were able to describe the excretion of the toxin beauvericin as main extrolite exclusively in liquid medium containing complex nitrogen and carbon sources, as well as the isolation of ergosterol derivate in mycelial extracts, which have potential for pharmaceutical uses. Therefore, culture conditions were also concluded to trigger some specific biosynthetic route favoring various metabolites of interest. Such observation is of great significance for selective production of pigments and/or prevention of occurrence of others (aka mycotoxins).