Fusarium mindanaoense sp. nov., a New Fusarium Wilt Pathogen of Cavendish Banana from the Philippines Belonging to the F. fujikuroi Species Complex.

The pathogen causing Fusarium wilt in banana is reported to be Fusarium oxysporum f. sp. cubense (FOC). In 2019, wilt symptoms in banana plants (cultivar: Cavendish) in the Philippines were detected, i.e., the yellowing of the leaves and discoloration of the pseudostem and vascular tissue. The fungus isolated from the vascular tissue was found to be pathogenic to Cavendish bananas and was identified as a new species, F. mindanaoense, belonging to the F. fujikuroi species complex (FFSC); species classification was assessed using molecular phylogenetic analyses based on the tef1, tub2, cmdA, rpb1, and rpb2 genes and morphological analyses. A reciprocal blast search using genomic data revealed that this fungus exclusively included the Secreted in Xylem 6 (SIX6) gene among the SIX homologs related to pathogenicity; it exhibited a highly conserved amino acid sequence compared with that of species in the FFSC, but not with that of FOC. This was the first report of Fusarium wilt in Cavendish bananas caused by a species of the genus Fusarium other than those in the F. oxysporum species complex.

Cytotoxicity of Medicinal Mushrooms Oudemansiella canarii and Ganoderma lucidum (Agaricomycetes) Against Hematologic Malignant Cells via Activation of Apoptosis-Related Markers.

Cancer is the second leading cause of death worldwide, and despite of the of the availability of the advanced chemical treatments, development of effective and safe alternatives derived from natural resources are still of high interest. Mushroom is one of the important resources of pharmacologically active cytotoxic compounds. In this paper, we report the cytotoxicity of ethanolic extracts of Oudemansiella canarii (Jungh.) Höhn. and Ganoderma lucidum (W. Curt.: Fr.) P. Karst. against nine hematologic malignant cells and describe their molecular mechanisms. Cell lines were exposed to varying concentrations of mushroom extracts for 48 h and the cell proliferation and apoptosis parameters were determined. Western blot analysis was performed to determine the extract-induced changes in the level of apoptosis-related proteins in cancer cell lines and patient-derived mononuclear cells. Results revealed that O. canarii and G. lucidum extracts exhibited cytotoxicity with IC50 values of 26.8-66.0 ppm and 48.1-78.4 ppm, respectively, in all the cancer cell lines used. Mushroom extracts inhibited cell proliferation by 57.3-72.5% (O. canarii) and 44.2-67.4% (G. lucidum), which correlates to the activation of apoptosis as indicated by increased annexin V positivity, cells in sub G0/G1 phase and production of reactive oxygen species, and decreased mitochondrial membrane potential. Western blot analysis showed increase in the level of apoptotic markers (cleaved PARP1, cleaved caspase 3 and phosphorylation of histone 2AX) and activation of the stress-activated protein kinase (SAPK/JNK) signaling pathway. The extract-activated apoptosis was also observed in mononuclear cells isolated from the peripheral blood of leukemia and lymphoma patients. In conclusion, activation of pro-apoptotic markers is one of the major mechanisms of the cytotoxicity of O. canarii and G. lucidum extracts against hematologic malignant cells.

Cytotoxicity of Gymnopilus purpureosquamulosus extracts on hematologic malignant cells through activation of the SAPK/JNK signaling pathway.

Treatment of hematologic malignancies is a formidable challenge for hematologists and there is an urgent need to identify safe and efficacious agents either via synthesis in the laboratory or isolation from natural products. Here, we report the cytotoxicity of extracts from mushroom Gymnopilus purpureosquamulosus Høil (G. pps) and describe its molecular mechanisms. Using leukemia, lymphoma and multiple myeloma cell lines, 28-35 ppm G. pps extract inhibited cell proliferation by ~46-79%, which correlates with activation of apoptosis as indicated by increase in annexin V-positive cells (~5-8-fold), production of reactive oxygen species (~2-3-fold), cells in sub G0/G1 phase (~3-13-fold), caspase 3 enzymatic activity (~1.6-2.9-fold), DNA fragmentation, PARP1 cleavage and down-regulation of prosurvival proteins. Mitochondrial membrane potential decreased and leakage of pro-apoptotic factors to cytoplasm was observed, consistent with the activation of intrinsic apoptosis. Western blot analysis showed activation of the ASK1-MEK-SAPK/JNK and ASK1-P38 MAPK pathways possibly due to changes in the cellular redox status as suggested by decreased protein levels of peroxiredoxin, thioredoxin and thioredoxin reductase. Moreover, antioxidant N-acetylcysteine alleviated the cytotoxicity of G. pps. Pharmacological inhibition of SAPK/JNK and P38 alleviated the G. pps-mediated cytotoxicity. The extract activated apoptosis in leukemia and lymphoma patient cell samples but not in mononuclear cells from healthy donors further supporting the therapeutic values of G. pps for hematologic malignancies.

Dietary Fiber Contents and Its Fermentability In Vitro of Pleurotus ostreatus cv. Florida Mycelia (Agaricomycetes).

Oyster mushrooms (Pleurotus spp.) constitute a substantial resource for functional food, as they are commercially cultivated worldwide and assumed to contain beneficial fiber. The objective of this study was to characterize and analyze the mycelia of Pleurotus ostreatus cv. Florida for its nutrient composition, total dietary fiber, insoluble dietary fiber, soluble dietary fiber content, and fermentability in vitro. Findings showed the mycelia had a moisture content of 18%, ash 12%, protein 5%, fat 0.1%, and carbohydrates 61%. Results also revealed that mycelia are an excellent source of dietary fiber (55%) containing high amounts of insoluble (22%) and soluble (33%) fiber. The mycelia also produced significant amounts of short chain fatty acids after fermentation at in vitro simulating conditions in the colon: acetate (1.92 mg/g), propionate (0.89 mg/g), and butyrate (0.31 mg/g). These results indicated that the mycelia of P. ostreatus cv. Florida are promising sources of dietary fiber.

Proximate composition and functionality of the culinary-medicinal tiger sawgill mushroom, Lentinus tigrinus (higher Basidiomycetes), from the Philippines.

The proximate composition and functionality of Lentinus tigrinus were evaluated to establish and popularize this mushroom as functional food source. The evaluation of functionality focused on the antibacterial and hypoglycemic activities of the mushroom extracts. An acute single oral dose toxicity test in mice was used for its biosafety analysis. The pileus contained higher amounts of protein (25.9%), fat (2.1%), and ash (7.4%) and a higher energetic value (142.1 kcal/100 g) than the corresponding stipe, whereas the stipe contained higher amounts of total carbohydrates (67.7%), which consist of dietary fiber (63.0%) and reducing sugar (4.7%), than the pileus. Biosafety analysis confirmed that L. tigrinus is an edible mushroom species; it was found to be toxicologically safe in imprinting control region mice. The administration of lyophilized hot water extract of the fruiting body (both 100 and 250 mg/ kg doses) to diabetic mice significantly lowered the glucose level by 26.9% in the third week, which was significantly comparable to the results of the antidiabetic agent glibenclamide, which was used as a positive control. In vitro antibacterial assay showed that the ethanolic extract of the fruiting body and the immobilized secondary mycelia had high antibacterial activities against Staphylococcus aureus but not on Escherichia coli. Combining its useful nutrients and significant biological properties, L. tigrinus can be considered a natural source of safe nutraceuticals.

Teratogenic and toxic effects of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.:Fr.) P. Karst. (higher Basidiomycetes), on zebrafish embryo as model.

This paper highlights the teratogenic and toxic effects of Ganoderma lucidum (Lingzhi or Reishi mushroom) extract on zebrafish embryos. Hatchability, malformations, and lethality rate of zebrafish embryos were assessed to provide valuable information regarding the potential teratogenic activity of G. lucidum. Hatching was completed 48 h post treatment application (hpta) at 1% or lower concentrations of extract and embryo water. The hatching rate of embryos treated with 5% or higher concentrations was significantly lower (p> 0.05) than the control. Tail malformation was the most marked morphological abnormality in embryos at 72 hpta, which was obviously caused by 1% extract (55.56% tail malformation) and was observed in all embryos exposed to 5% of extract. Growth retardation was evident in embryos exposed to 5%, 10%, and 20%. However, lethal effect of extract of G. lucidum was dependent on dose and time of exposure. Mortality rates of embryos treated with 5% (44.44%) or higher concentrations of the extract was significantly higher (p > 0.05) than that of the control embryos at 72 hpta. These results suggest that G. lucidum extract has lethal and sub-lethal effects on zebrafish embryos.