Efficacy of Bottle Gourd Seeds’ Extracts in Chemical Hazard Reduction Secreted as Toxigenic Fungi Metabolites

Bottle gourd seeds are surrounded by innumerable bioactive components of phytochemicals. This work aimed to evaluate the effectiveness of bottle gourd extracts as antimicrobial and an-ti-mycotoxigenic against toxigenic fungi and mycotoxins. Polar and nonpolar extracts were made from the seeds. The polar eco-friendly extract was prepared by an ultrasonication-assisted technique utilizing aqueous isopropanol (80%), whereas the non-polar extract was obtained using petroleum ether (40–60). The antioxidant efficacy, total phenolic content, and flavonoid content of the extracts were all measured. The fatty acid profile was measured using GC equipment, and the influence on toxigenic fungus and mycotoxin release was also investigated. The antioxidant efficacy of the polar extract is reflected. The total phenolic values of the oil and polar extract were 15.5 and 267 mg of GAE/g, respectively. The total flavonoid content of the oil was 2.95 mg catechol/g, whereas the isopropyl extract of seeds contained 14.86 mg catechol/g. The polar extract inhibited the DPPH more effectively than oil. When compared to other seed oils, the fatty acid composition differed. The pathogens were distinguished by the MIC and MFC for the polar extract. Three sterols were found in the oil, with a high concentration of B-sitosterols. The oil’s valuable -carotene content and tocopherol content were recorded. When compared to traditional antibiotics, the polar extract has shown promising antimicrobial activity against infections and toxigenic fungi. Bottle gourd extracts, as a non-traditional bioactive source, are viewed as a potentially promising alternative that might contribute to increased food safety, shelf-life, and security.

Occurrence and Characterization of Penicillium Species Isolated from Post-Harvest Apples in Lebanon

The apple is one of the most important fruit tree crops in the Mediterranean region. Lebanon, in particular, is among the top apple producer countries in the Middle East; however, recently, several types of damage, particularly rot symptoms, have been detected on fruits in cold storage. This study aims to identify the causal agents of apple decay in Lebanese post-harvest facilities and characterize a set of 39 representative strains of the toxigenic fungus Penicillium. The results demonstrated that blue mould was the most frequent fungal disease associated with apples showing symptoms of decay after 3–4 months of storage at 0 °C, with an average frequency of 76.5% and 80.6% on cv. Red and cv. Golden Delicious apples, respectively. The morphological identification and phylogenetic analysis of benA gene showed that most Penicillium strains (87.2%) belong to P. expansum species whereas the remaining strains (12.8%) belong to P. solitum. Furthermore, 67.7% of P. expansum strains produced patulin when grown on apple puree for 14 days at 25 °C with values ranging from 10.7 mg kg−1 to 125.9 mg kg−1, whereas all P. solitum did not produce the mycotoxin. This study highlights the presence of Penicillium spp. and their related mycotoxin risk during apple storage and calls for the implementation of proper measures to decrease the risk of mycotoxin contamination of apple fruit products.

The Effective Role of Soil Indigenous Fungi on 2.4-D Herbicide Degradation

The normal field soil environment safeguarded, via indigenous microbes in a native manner, with the aim of turning herbicide waste into productive bio-resources, through fungi activities. This study aims to determine the effective role of soil indigenous fungi on 2,4-D herbicide degradation. The research was conducted over a period of six weeks, on Iraqi cereal field. A total of eight fungi species, belonging to six genera, (Aspergillus candidus L. ATCC 1002, A. niger T. ATCC 16888, Curvularia lunata W. B1933, Penicillium sp. L. 1809, Rhizopus stolonifer L. B9770, Stachybotrys atra C. 1837, Trichoderma harzianum R. IOC 3844, and T. lignorum T. Hartz 1872), were isolated from the soil. During the exposure periods, fungal populations were differently affected, upon treatments with herbicide. The applied herbicide treatments showed different effects on growth and development of the isolated fungi. The results showed that, five of the eight fungi species (C. lunata B1933, Penicillium sp. 1809, R. stolonifer B9770, T. harzianum IOC 3844, and T. lignorum Hartz 1872) were greatly enhanced by the treatment process. However, two fungi (S. atra 1837, and A. candidus ATCC 1002) were affected negatively by the herbicide, while one (A. niger ATCC 16888) remained unaffected. Once extracted from the soil of wheat fields in Iraq, the fungus S. atra 1837, was first isolated. The highest inhibitory effect was caused by 2,4-D herbicide, on the toxigenic fungus S. atra, causing its disappearance from the field at the last week of application. The laboratory experiments showed similar herbicide effects on the isolated fungi at low and moderate levels, while those at the high level (800 µg /ml) were toxic. These results showed that the herbicide 2,4-D treatments have substantial effects on microbial population in the field. When applied at recommended field rate, the herbicide causes transient impacts on fungal population growth and biodiversity, with the majority of the organism becoming responsible for 2,4-D mineralization in the soil. Therefore, the use of 2,4-D herbicide does not only control weed population, but it also affects microbial activities, especially indigenous fungi in the soil.

Polyphasic reassessment of a yellow rice fungus, Penicillium toxicarium

From historical strain records, Penicillium citreonigrum NBRC 4692 was originally isolated as the toxigenic fungus responsible for the yellow rice incident in Japan in 1937. The fungus was named Penicillium toxicarium by I. Miyake, which was considered invalid due to the lack of a Latin diagnosis. Initially, it was named Penicillium sp. by Miyake et al. in 1940. Subsequently, P. toxicarium, which was erroneously cited as synonym of P. citreo-viride, was validated by C. Ramírez in 1982 with a Latin diagnosis and type designation (CBS 351.51). Later, CBS 351.51 was assigned to Penicillium trzebinskii by Houbraken et al. in 2014. In 2016, P. toxicarium was treated as a synonym of Penicillium citreosulfuratum based on a conclusion of molecular phylogenetic analysis. Recently, we discovered the taxonomic and nomenclatural short communication (in Japanese) by I. Miyake in 1947 on P. toxicarium sp. nov. with its Latin description and four illustrations but lacking the type designation. In this paper, we re-examined strain NBRC 4692 for its current taxonomic position based on morphological characteristics and molecular phylogenetic analysis. NBRC 4692 (received from I. Miyake in 1951) has been found to have the same morphological characteristics as P. toxicarium, as was shown in Miyake's diagnosis in 1947. Phylogenetic analysis revealed that the NBRC strain belongs to a unique clade, different from the clade comprising P. citreosulfuratum strains. As a conclusion, herein, P. toxicarium I. Miyake (1947) is reinstated as a correct name with the lectotype designation.

Detoxification assessment of Aflatoxin in Aspergillus flavus under the effect of Calendula officinalis Linn’s methanolic extract

Calendula officinalis Linn (pot marigold) possess potential pharmacological activities which might be considered as an excellent cause, in scheming the aflatoxin biosynthesis in the aflatoxigenic fungi. The aim of the present study was to assess the antifungal activity of methanol extracts of the plant petals against biosynthesis of aflatoxin B1 (AFB1) in Aspergillus flavus. The antifungal potential of methanolic extract of C. officinalis was evaluated against the toxigenic fungus on Czapek Dox Agar (CDA) and Czapek Dox Broth (CDB) Media, using disc diffusion assay. The use of C. officinalis extract on the A. flavus culture showed the significant inhibition of AFB1up to 59.50% along with the reduction of mycelial growth to about 24.82%. Although, the treatment of the AFB1 with the extract for 5 hours at 80ºC which led to 78.48%. The work well established the inhibitory role of C. officinalis extract in order to reduce the AFB1 threat.

Root hair-endophyte stacking (RHESt) in an ancient Afro-Indian crop creates an unusual physico-chemical barrier to trap pathogen(s)

The ancient African crop, finger millet, has broad resistance to pathogens including the toxigenic fungusFusarium graminearum. Here we report the discovery of a novel plant defence mechanism, resulting from an unusual symbiosis between finger millet and a root-inhabiting bacterial endophyte, M6 (Enterobactersp.). Seed-coated M6 swarms towardsFusariumattempting to penetrate root epidermis, induces growth of root hairs which then bend parallel to the root axis, then forms biofilm-mediated microcolonies, resulting in a remarkable, multi-layer root hair-endophyte stack (RHESt). RHESt results in a physical barrier that prevents entry and/or trapsF. graminearumwhich is then killed. Thus M6 creates its own specialized killing microhabitat. M6 killing requires c-di-GMP-dependent signalling, diverse fungicides and xenobiotic resistance. Further molecular evidence suggests long-term host-endophyte-pathogen co-evolution. The end-result of this remarkable symbiosis is reduced DON mycotoxin, potentially benefiting millions of subsistence farmers and livestock. RHESt demonstrates the value of exploring ancient, orphan crop microbiomes.

Mushrooms versus fungi: natural compounds from Lentinula edodes inhibit aflatoxin biosynthesis by Aspergillus parasiticus

Although the strategies routinely adopted to limit production of carcinogenic aflatoxins by Aspergillus parasiticus and Aspergillus flavus in foods and feeds can be quite effective, they are often neither environmentally friendly, nor non-toxic for end users. Polysaccharides and glycoproteins, particularly β-glucans from the basidiomycete Lentinula edodes, already known for their health-promoting effects on animals and humans, have previously demonstrated the ability to inhibit aflatoxin biosynthesis by stimulating the antioxidant defences of the toxigenic fungus. Here the results of a study regarding the influence on polysaccharide production by L. edodes of oxidative stress induced using paraquat (PQ) treatment are reported. Paraquat 0.5 and 1 mM resulted in an enhancement of the expression of the β-glucan synthase gene Lefks1 and a consequent stimulating effect (about 30-35%) on β-glucans production. Moreover, oxidative-stress (PQ) induced polysaccharides have a higher aflatoxin inhibiting capacity in two different strains of A. parasiticus in comparison with non-induced polysaccharides. This more efficient inhibition might be explained by a higher content of β-glucans because 1H-NMR analysis revealed no obvious qualitative differences between PQ-induced and non-induced polysaccharides. The results obtained show promise for improving the quantity and efficiency of L. edodes extracts in order to achieve enhanced control over aflatoxin biosynthesis in foods and feeds using health-promoting and environmentally-friendly compounds.