Eurotium Amstelodami Research Articles

Metabolomic profiles of the liquid state fermentation in co-culture of Eurotium amstelodami and Bacillus licheniformis.

As an important source of new drug molecules, secondary metabolites (SMs) produced by microorganisms possess important biological activities, such as antibacterial, anti-inflammatory, and hypoglycemic effects. However, the true potential of microbial synthesis of SMs has not been fully elucidated as the SM gene clusters remain silent under laboratory culture conditions. Herein, we evaluated the inhibitory effect of Staphylococcus aureus by co-culture of Eurotium amstelodami and three Bacillus species, including Bacillus licheniformis, Bacillus subtilis, and Bacillus amyloliquefaciens. In addition, a non-target approach based on ultra-performance liquid chromatography time-of-flight mass spectrometry (UPLC-TOF-MS) was used to detect differences in extracellular and intracellular metabolites. Notably, the co-culture of E. amstelodami and Bacillus spices significantly improved the inhibitory effect against S. aureus, with the combination of E. amstelodami and B. licheniformis showing best performance. Metabolomics data further revealed that the abundant SMs, such as Nummularine B, Lucidenic acid E2, Elatoside G, Aspergillic acid, 4-Hydroxycyclohexylcarboxylic acid, Copaene, and Pipecolic acid were significantly enhanced in co-culture. Intracellularly, the differential metabolites were involved in the metabolism of amino acids, nucleic acids, and glycerophospholipid. Overall, this work demonstrates that the co-culture strategy is beneficial for inducing biosynthesis of active metabolites in E. amstelodami and B. licheniformis.

Characterization of fungal exposure and dectin-1 expression in healthy horses and horses with severe asthma.

To quantify dectin-1 expression in bronchoalveolar lavage fluid (BALF), create polyclonal antibodies against equine dectin-1 and localize it in tissues, and quantify fungal exposure in pastured and stabled asthmatic and nonasthmatic horses. BALF samples from 6 controls and 6 horses with severe asthma. Stored lung and nasal wash samples. Dectin-1 expression was quantified by quantitative PCR (qPCR). Purified peptide from equine dectin-1 was used to generate polyclonal antibodies and was confirmed with immunological testing. Fungal exposure was quantified in BALF samples by counting fungal-like intracellular particles in phagocytic cells, by qPCR quantification of the "universal" 18S rRNA fungal gene, and by quantifying 36 specific fungi in equine and dust samples using qPCR assays. Equine dectin-1 was localized in tissues and cells, and functional isoforms were upregulated significantly in BALF after stabling. Pastured horses from both groups had low levels of fungi in BALF, and there was a significant increase in some specific fungi, most notably for Eurotium amstelodami, Wallemia sebi, and Aspergillus niger after stabling. However, stabled asthmatic horses had fewer phagocytized particles, less 18S rRNA signal, and fewer specific fungi compared to nonasthmatic horses. Stabling increases exposure to fungi, but asthmatic horses had fewer fungi reaching their lower airways, presumably resulting from congestion and narrowing of the airways. Exposure to fungi could contribute to airway inflammation by increasing dectin-1 functional isoforms, and exposure to indoor molds should be avoided.

Fungal diversity and mycotoxins detected in maize stored in silo-bags: a review.

Silo-bags are hermetic storage systems that inhibit fungal growth because of their atmosphere with low humidity, as well as low pH and O2 concentrations, and a high CO2 concentration. If a silo-bag with stored maize loses its hermetic nature, it favors the development of fungi and the production of mycotoxins. To the best of our knowledge, this is the first review on the diversity of fungal species and mycotoxins that were reported in maize stored under the environmental conditions provided by silo-bags. The genera Penicillium, Aspergillus and Fusarium were found more frequently, whereas Acremonium spp., Alternaria sp., Candida sp., Cladosporium sp., Debaryomyces spp., Epiconum sp., Eupenicillium spp., Eurotium sp., Eurotium amstelodami, Hyphopichia spp., Hyphopichia burtonii, Moniliella sp., Wallemia sp. and genera within the orden Mucorales were reported less recurrently. Despite finding a great fungal diversity, all of the studies focused their investigations on a small group of toxins: fumonisins (FBs), aflatoxins (AFs), deoxynivalenol (DON), zearalenone (ZEA), patulin (PAT), toxin T2 (T2) and ochratoxin (OT). Of the FBs, fumonisin B1 and fumonisin B2 presented higher incidence percentages, followed by fumonisin B3 . Of the AFs, the only one reported was aflatoxin B1. The mycotoxins DON, ZEA and OT were found with lower incidences, whereas PAT and T2 were not detected. Good management practices of the silo-bags are necessary to achieve a hermetically sealed environment, without exchange of gases and water with the external environment during the storage period. © 2022 Society of Chemical Industry.

Hepatoprotective activity of Phyllanthus niruri Linn. endophytes

BackgroundThe liver is the vital organ which plays a major role in metabolism with numerous functions in the human beings such as protein synthesis, hormone production, and detoxification. Present research work is focused on hepatoprotective potential of chloroform (PNFC) and ethyl acetate (PNFEA) endophytic fractions from Phyllanthus niruri Linn. against CCl4-induced hepatotoxicity in albino Wistar rats. To test our hypothesis, both endophytic fungal fractions were tested for vitro antioxidant and in vivo hepatoprotective activity. Serum biochemical parameters like SGOT, SGOT, SALP, cholesterol, bilirubin, and protein were estimated to assess hepatoprotective activity.ResultsGroup of rats treated with CCl4 possess marked hepatic damage and oxidative stress which indicates that cellular leakage and loss of functional integrity of cell membrane in liver. PNFC and PNFEA fractions of endophyte from Phyllanthus niruri Linn. stem have significantly reduced the elevated levels of biomarkers like SGPT, SGOT, SALP, bilirubin, cholesterol, and total protein in CCl4-induced hepatotoxicity in rats. The results obtained confirm hepatoprotective activity of endophytic fractions (PNFC and PNFEA) mediated through the stabilization of plasma membrane, repair of hepatic tissue damage, return of biochemical marker levels to normal, and regeneration of hepatocytes. Histopathological observations revealed improvement in the liver architecture after the treatment of secondary metabolites of endophytic fractions against CCl4-induced liver damage. Both fungal endophytes PNFC and PNFEA showed DPPH scavenging activity with IC50 of 97.79 μg/ml and 108.40 μg/ml, respectively, and possess antioxidant potential. Presence of flavonoids in the both fractions of endophytes may be a possible reason for its antioxidant potential and identified as Eurotium amstelodami strain.ConclusionBoth fungal endophytes PNFC and PNFEA possess hepatoprotective potential due to the presence of secondary metabolites of fungi, i.e., Eurotiumam stelodami strain which support the claim endophytes and act as a potent biomedicine for treatment of various chronic diseases.

Growth characterization and predictive behavior of Eurotium species in a feedstuff matrix

Animal feeds are characterized by low water activity values. Nevertheless, fungal contamination with Eurotium species are quite common, causing nutritional depletion, spoilage and economic losses.The aim of this work was to assess Eurotium amstelodami, E. chevalieri, E. repens and E. rubrum growth in a feed matrix at different conditions of water activity (0.71–0.97) and temperature (5, 15, 25, 30 and 37°C).It was found that Eurotium species are able to grow in a wide range of water activity and temperature in a short period of time (7 days) and faster than in synthetic media. Rosso and probabilistic models were applied in order to determine the limiting and optimum growth conditions as well as growth probability at certain combinations of environmental factors. Both models provided an accurate fit to the cardinal parameters and good performance for growth/no growth cases.This is the first report assessing the growth parameters of Eurotium species directly in animal feed. Data obtained in the present study is useful to predict and avoid Eurotium species growth in animal feed.

Microbial lag phase can be indicative of, or independent from, cellular stress

Measures of microbial growth, used as indicators of cellular stress, are sometimes quantified at a single time-point. In reality, these measurements are compound representations of length of lag, exponential growth-rate, and other factors. Here, we investigate whether length of lag phase can act as a proxy for stress, using a number of model systems (Aspergillus penicillioides; Bacillus subtilis; Escherichia coli; Eurotium amstelodami, E. echinulatum, E. halophilicum, and E. repens; Mrakia frigida; Saccharomyces cerevisiae; Xerochrysium xerophilum; Xeromyces bisporus) exposed to mechanistically distinct types of cellular stress including low water activity, other solute-induced stresses, and dehydration-rehydration cycles. Lag phase was neither proportional to germination rate for X. bisporus (FRR3443) in glycerol-supplemented media (r2 = 0.012), nor to exponential growth-rates for other microbes. In some cases, growth-rates varied greatly with stressor concentration even when lag remained constant. By contrast, there were strong correlations for B. subtilis in media supplemented with polyethylene-glycol 6000 or 600 (r2 = 0.925 and 0.961), and for other microbial species. We also analysed data from independent studies of food-spoilage fungi under glycerol stress (Aspergillus aculeatinus and A. sclerotiicarbonarius); mesophilic/psychrotolerant bacteria under diverse, solute-induced stresses (Brochothrix thermosphacta, Enterococcus faecalis, Pseudomonas fluorescens, Salmonella typhimurium, Staphylococcus aureus); and fungal enzymes under acid-stress (Terfezia claveryi lipoxygenase and Agaricus bisporus tyrosinase). These datasets also exhibited diversity, with some strong- and moderate correlations between length of lag and exponential growth-rates; and sometimes none. In conclusion, lag phase is not a reliable measure of stress because length of lag and growth-rate inhibition are sometimes highly correlated, and sometimes not at all.

Evaluation of molecular identification of Aspergillus species causing fungal keratitis.

Fungal keratitis caused by the species of Aspergillus is a common and leading problem in developing countries like India. In this study, a total of 135 isolates from Aspergillus keratitis were studied by sequence analyses of the internal transcribed spacer (ITS) region performed by nucleotide-nucleotide BLAST analysis followed by the initial identification of the isolates based on conidial and colony morphology. The sequence analysis revealed several unusual species which were never reported in eye infections such as A. tamrii, A. tubingensis, A. braslliensis, A. nomius, A. pseudonomius, A. sydowii, Eurotium amstelodami. The sequence analysis of the ITS region; the β-tubulin and calmodulin genes brought out the genetic diversity among the isolates as the study intended to locate a more sensitive target sequence to study genetic diversity among a set of test fungal isolates. The PCR amplified sequences of the test isolates of the study as well as sequences belonging to section Flavi obtained from Genbank database were compared and analyzed along with three standard isolates by phylogenetic tree (Neighbor-joining) as to find out a target region/gene that could produce a better resolution to differentiate the isolates. Accordingly, the calmodulin gene had provided better resolution compared to ITS and β-tubulin to study the diversity among the test Aspergillus species isolated from fungal corneal ulcer.

Bioconversion of Flavonoid Glycosides from Hippophae rhamnoides Leaves into Flavonoid Aglycones by Eurotium amstelodami.

The flowering process has been reported to play crucial roles in improving the flavor and efficacy of fermented tea. Hippophae rhamnoides leaves containing many beneficial ingredients are a suitable plant source for tea processing. In this study, we isolated a β-glucosidase-producing fungus Eurotium amstelodami BSX001 from the fermented tea and used Hippophae rhamnoides leaves (HRL) as a substrate to explore the detailed process of bioconversion of some important functional factors. The results show that the contents of total phenolic compounds and flavonoids increased significantly after seven days, especially flavonoid aglycones (e.g., quercetin, kaempferol, and isorhamnetin). Such compounds greatly enhance the antioxidative activity of fermented products. Metabolic analysis of the standard compounds (rutin, quercetin-3-glucoside, kaempferol-3-glucoside, quercetin, isorhamnetin-3-glucoside, isorhamnetin, and kaempferol) further confirmed the effective biotransformation by E. amstelodami. Mechanisms of the bioconversion could be involved in deglycosylation, dihydroxylation, and O-methylation. Our findings expand the understanding of tea fermentation process and provide further guidance for the fermented tea industry.

Antifungal activity of chitosan oligomer prepared using chitosanase of Aeromonas media KLU 11.16

Chitosan oligomer is a hydrolysis product of chitosan which can be prepared by enzymatic method, including chitosanase that may be produced by bacteria. Previously, chitosanase from Aeromonas media KLU 11.16 has been purified and characterized. The aim of this study was to analyze the bioactivity of chitosan oligomer prepared by using Aeromonas media KLU 11.16 chitosanase, as antifungal. Chitosan oligomer was prepared from shrimp waste chitosan, and hydrolyzed by 8U chitosanase per gram chitosan. The reaction time was for 2, 3 and 4 hours at 30°C. The oligomer produced then determined their yields and viscosities; and was identified by using a thin layer chromatography (TLC). Antifungal activity test against Aspergilus flavus, A. niger, Eurotium amstelodami and Emericella nidulans was performed on selected oligomers based on consideration of yield and TLC result, with oligomer concentrations of 0; 50; 100 and 200 ppm. The result showed that hydrolysis chitosan by Aeromonas media KLU 11.16 chitosanase for 4 hours reduced the viscosity from 187.5 to 13 cPs, and produced oligomers 96.14% of yield. The oligomers identified by TLC were monomer (1 unit) to hexamer (6 unit), and showed their antifungal activity against the four fungi tested. The best inhibition was showed by 200 ppm of oligomer against A. flavus.

Investigation of diversity and dominance of fungal biota in stored wheat grains from governmental warehouses in West Bengal, India.

Fungal infestation is a leading cause of qualitative and quantitative deterioration of stored wheat grains. Limited information is available on the spatial distribution of fungal biota associated with stored wheat grains in India. Fungi were isolated and characterized from nine stored wheat grain samples in three warehouses of the Food Corporation of India, located in three agro-climatic zones (Paschim Medinipur, Bankura and Purulia) of West Bengal in India. Maximum density and fungal diversity were observed in dichloran glycerol agar (DG-18) medium and the number increased with the increase of storage duration. Samples collected from Purulia showed maximum fungal diversity than that from Bankura and Paschim Medinipur. A total of 284 fungal isolates were obtained, classified into 29 operational taxonomic units (based on amplified ribosomal DNA restriction analysis of 18S and internal transcribed spacer sequences), and identified as 24 different fungal species. The majority of fungal isolates belonged to Aspergillus flavus (35%) followed by Rhizopus oryzae (13%) and Eurotium amstelodami (9%). Aspergillopepsin O (PEPO) gene and aflatoxin biosynthetic pathway gene, nor-1, were amplified by polymerase chain reaction (PCR) from 91% and 71% of Aspergillus flavus isolates, respectively, indicating their aflatoxin producing ability. Aflatoxin production was further confirmed by ammonia vapour test, thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The presence of toxigenic fungi in stored wheat grain emphasizes the necessity of quarantine measures of stored grains before placing them in the public domain to save consumers from health hazards. © 2019 Society of Chemical Industry.

Microbial exposure to dairy farmers’ dwellings and COPD occurrence

ABSTRACTDairy farming is a risk factor for chronic obstructive pulmonary disease (COPD). The aim was to determine predictive markers either in blood samples or in dwelling dust samples by comparing COPD and healthy controls with or without farming activity.Dust was collected and analyzed by real-time quantitative PCR. ELISA and DELFIA® were performed to assay the level of specific IgG and IgE of 10 targeted microorganisms.The dwelling exposure of farmers was higher than in the non-farmers (Especially Eurotium amstelodami and Lichtheimia corymbifera). The IgG response against Wallemia sebi and Saccharopolyspora rectivirgula was more often higher in the farmers than the non-farmers. However, exposure and sensitization to the microorganisms tested cannot explain the occurrence of COPD in the dairy farmers’ population. COPD development is probably caused by multiple factors associated with exposure over a period of several years.

Asperflavin, an Anti-Inflammatory Compound Produced by a Marine-Derived Fungus, Eurotium amstelodami.

In the present study, 16 marine-derived fungi were isolated from four types of marine materials including float, algae, animals and drift woods along with the coast of Jeju Island, Korea and evaluated for anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW 24.7 cells. The broth and mycelium extracts from the 16 fungi were prepared and the broth extract (BE) of Eurotium amstelodami (015-2) inhibited nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells without cytotoxicity. By further bioassay-guided isolation, three compounds including asperflavin, neoechinulin A and preechinulin were successfully isolated from the BE of E. amstelodami. It was revealed that asperflavin showed no cytotoxicity up to 200 μM and significantly inhibited LPS-induced NO and PGE2 production in a dose-dependent manner. In the western blot results, asperflavin suppressed only inducible NOS (iNOS), but COX-2 were slightly down-regulated. Asperflavin was also observed to inhibit the production of pro-inflammatory cytokines including TNF-α, IL-1β, and IL-6. In conclusion, this study reports a potential use of asperflavin isolated from a marine fungus, E. amstelodami as an anti-inflammatory agent via suppression of iNOS and pro-inflammatory cytokines as well as no cytotoxicity.

Disinfection of ancient paper contaminated with fungi using supercritical carbon dioxide

Abstract Fungi continue to be the main cause of biodeterioration in libraries. In addition to degrading paper, fungi are an important health issue for librarians and even library users. The aim of this study was to investigate the application of supercritical carbon dioxide (SCCO 2 ) to ancient paper contaminated with fungi. For this purpose, SCCO 2 was applied in two processes to treat samples of paper pieces: addition of 4% and 8% ethanol (w/w) at a pressure of 150 bar and temperature of 40 °C for 1 hour. Control samples (no processing) and processed samples were directly plated onto culture media to evaluate the frequency of fungal growth. Morphological and molecular analysis of the 294 samples showing mold growth on paper revealed that Aspergillus niger , Aspergillus flavus , and Eurotium amstelodami were the most frequently isolated fungi. In the control group, 47.6% of the samples were contaminated with fungi. This percentage was only 1.9% after treatment with both processes. The difference between unprocessed control samples and samples treated under the two conditions was statistically significant ( P

FUNGAL DIVERSITY ASSOCIATED WITH PEARL MILLET PENNISETUM GLAUCUM L.) GRAINS FROM TAIZ GOVERNORATE, YEMEN AND THEIR AMYLASE PRODUCTION

In Yemen, this is the first record on fungal diversity associated with millet grains. Grain- borne fungi were tested for NaOCl- treated and non- treated samples of millet grain collected from Taiz Governorate, Yemen using direct plate method on Czapek’s (Cz) and Czapek’s supplemented with 40% sucrose (Cz40S) agar media. A total of 48 species belonging to 20 genera were isolated. The highest count and number of genera and species were recorded in non- treated grains on Cz40S medium. This means that the majority of fungi associated with grains were osmotolerant/osmophilic. The highest frequencies were represented by Aspergillus flavus, A. niger aggregate, A. vadensis, Eurotium amstelodami, Pencillium duclauxii and Rhizopus stolonifer. Among 109 isolates screened for their ability to produce amylase enzyme, 81.65% could produce the enzyme, of which Aspergillus homomorphus (a new record in Egypt), Emericella nidulans, Fusarium oxysporum and Penicillium griseofulvum were the best producers. Hence, these fungi may cause degradation of cell walls and spoilage of grains. Moreover, it is important to determine which organisms might be associated with seeds and grains in storage causing quality loss through their growth and enzyme production. The early detection of these organisms is required to prevent their harmful effects.

Characterization of the translation elongation factor 1-α gene in a wide range of pathogenic Aspergillus species.

We aimed to evaluate the resolving power of the translation elongation factor (TEF)-1α gene for phylogenetic analysis of Aspergillus species. Sequences of 526 bp representing the coding region of the TEF-1α gene were used for the assessment of levels of intra- and inter-specific nucleotide polymorphism in 33 species of Aspergillus, including 57 reference, clinical and environmental strains. Analysis of TEF-1α sequences indicated a mean similarity of 92.6 % between the species, with inter-species diversity ranging from 0 to 70 nucleotides. The species with the closest resemblance were A. candidus/A. carneus, and A. flavus/A. oryzae/A. ochraceus, with 100 and 99.8 % identification, respectively. These species are phylogenetically very close and the TEF-1α gene appears not to have sufficient discriminatory power to differentiate them. Meanwhile, intra-species differences were found within strains of A. clavatus, A. clavatonanicus, A. candidus, A. fumigatus, A. terreus, A. alliaceus, A. flavus, Eurotium amstelodami and E. chevalieri. The tree topology with strongly supported clades (≥70 % bootstrap values) was almost compatible with the phylogeny inferred from analysis of the DNA sequences of the beta tubulin gene (BT2). However, the backbone of the tree exhibited low bootstrap values, and inter-species correlations were not obvious in some clades; for example, tree topologies based on BT2 and TEF-1α genes were incompatible for some species, such as A. deflectus, A. janus and A. penicillioides. The gene was not phylogenetically more informative than other known molecular markers. It will be necessary to test other genes or larger genomic regions to better understand the taxonomy of this important group of fungi.

Fungi Associated with Maize and Sorghum Grains and their Potential for Amylase and Aflatoxins Production

USING direct-plating technique, thirty-nine species belonging to 16 fungal genera were isolated from maize and sorghum grain samples (20 samples each) on Czap ek’s agar (Cz) and Czap ek’s supplemented with 40% sucrose agar (Cz40S) media at 28oC. Widest spectrum of genera and species were recorded on sorghum (16 genera and 35 species) compared with maize grains (8 and 19). The highest total counts (139 CFUs/ 100 grains) and the number of genera (14) and species (27) were identified from sorghum grains on Cz medium. The most common fungi on the grains tested were Aspergillus flavus, A. niger, Eurotium amstelodami, E. rubrum, E. repens, Fusarium verticillioides and Rhizopus stolonifer. Among 129 isolates screened for their abilities to produce amylase enzyme, 102 isolates could produce this enzyme, of which A. terreus exhibited the highest production (EI=1.73). HPLC analysis revealed that out of 6 strains of A. flavus tested, strain No. AUMC 11311 showed the highest production of aflatoxin B1 and B2, while the highest value of aflatoxin G2 was produced by strain No. AUMC 11317. It could be concluded that fungi growing on grains and their abilities for producing enzymes and aflatoxins might cause deterioration and spoilage of these grains.

Glycerol enhances fungal germination at the water-activity limit for life.

SummaryFor the most‐extreme fungal xerophiles, metabolic activity and cell division typically halts between 0.700 and 0.640 water activity (approximately 70.0–64.0% relative humidity). Here, we investigate whether glycerol can enhance xerophile germination under acute water‐activity regimes, using an experimental system which represents the biophysical limit of Earth's biosphere. Spores from a variety of species, including Aspergillus penicillioides, Eurotium halophilicum, Xerochrysium xerophilum (formerly Chrysosporium xerophilum) and Xeromyces bisporus, were produced by cultures growing on media supplemented with glycerol (and contained up to 189 mg glycerol g dry spores−1). The ability of these spores to germinate, and the kinetics of germination, were then determined on a range of media designed to recreate stresses experienced in microbial habitats or anthropogenic systems (with water‐activities from 0.765 to 0.575). For A. penicillioides, Eurotium amstelodami, E. halophilicum, X. xerophilum and X. bisporus, germination occurred at lower water‐activities than previously recorded (0.640, 0.685, 0.651, 0.664 and 0.637 respectively). In addition, the kinetics of germination at low water‐activities were substantially faster than those reported previously. Extrapolations indicated theoretical water‐activity minima below these values; as low as 0.570 for A. penicillioides and X. bisporus. Glycerol is present at high concentrations (up to molar levels) in many types of microbial habitat. We discuss the likely role of glycerol in expanding the water‐activity limit for microbial cell function in relation to temporal constraints and location of the microbial cell or habitat. The findings reported here have also critical implications for understanding the extremes of Earth's biosphere; for understanding the potency of disease‐causing microorganisms; and in biotechnologies that operate at the limits of microbial function.

An Impedance-Based Mold Sensor with on-Chip Optical Reference.

A new miniaturized sensor system with an internal optical reference for the detection of mold growth is presented. The sensor chip comprises a reaction chamber provided with a culture medium that promotes the growth of mold species from mold spores. The mold detection is performed by measuring impedance changes with integrated electrodes fabricated inside the reaction chamber. The impedance change in the culture medium is caused by shifts in the pH (i.e., from 5.5 to 8) as the mold grows. In order to determine the absolute pH value without the need for calibration, a methyl red indicator dye has been added to the culture medium. It changes the color of the medium as the pH passes specific values. This colorimetric principle now acts as a reference measurement. It also allows the sensitivity of the impedance sensor to be established in terms of impedance change per pH unit. Major mold species that are involved in the contamination of food, paper and indoor environments, like Fusarium oxysporum, Fusarium incarnatum, Eurotium amstelodami, Aspergillus penicillioides and Aspergillus restrictus, have been successfully analyzed on-chip.

Extremophiles as Biofactories of Novel Antimicrobials and Cytotoxics – An Assessment of Bioactive Properties of Six Fungal Species Inhabiting Rann of Kutch, India

Objective: In this study we report the antibacterial and cytotoxic activity of the fungi isolated from Little Rann of Kutch, India. Methods: Antibacterial activity of crude extracts of 35 fungal isolates was assessed at an initial concentration of 40μg/ml against Klebsiella pneumoniae and Escherichia coli. Promising fungal isolates were identified by their morphology. Extracts of identified isolates were further tested at varying concentrations (10-40μg/ml) against Staphylococcus aureus and Bacillus cereus apart from K. pneumoniae and E. coli. Cytotoxic activity was assessed against cancer cell line MCF- 7. Phenol, flavonoid and alkaloid estimation was done to understand the fungi’s chemoprofile. Findings: In preliminary screening, six isolates showed significant activity against K. pneumoniae (14-17 mm) and E. coli (14-22 mm). These were identified as Aspergillus flavus, A. cremeus, A. versicolor, A. terreus, Penicillium purpurogenum and Eurotium amstelodami . On further evaluation of fungal extracts against four test pathogens, A. versicolor was found to be the most effective (8-11 mm), followed by A. terreus (8-10 mm) and A. cremeus (8-10 mm) at 10μg/ml each. A. versicolor and P. purpurogenum were found to be most cytotoxic, with IC50 values of 6.26 and 6.30 respectively, followed by A. flavus, E. amstelodami, A. cremeus and A. terreus. Phenolic content was highest in A. versicolor (268.77±0.18 μg/mg GAE); flavonoid and alkaloid were maximum in P. purpurogenum - 91.17±0.44 μg/mg QE and 89.13±0.28 μg/mg PNE, respectively. Improvements/Applications: Six fungi isolated from Little Rann of Kutch, India, hold tremendous potential as a source of novel antimicrobials and cytotoxics. The results warrant more exhaustive bioassays and identification of active principles.

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