20 research outputs found
Inventory of the Genus Craterellus Persoon from Kigoma Region, Tanzania
There is scanty knowledge on macro fungi diversity in Kigoma region. Bioprospecting survey was undertaken in Miombo woodlands, Kigoma region of Tanzania that has never been explored. The survey sought to conduct an inventory of Craterellus Persoon. Conventional taxonomic techniques were used during the survey to characterize the collected materials. Both macro and micro morphological features including basidiocarp size, colour, shape, spore size and print colour were examined. High diversity of reputed macrofungi was observed. This study presents a preliminary inventory of the genus Craterellus Persoon in the country. Three species were described; two namely Craterellus cornucopioides (Linnaeus) Persoon and Craterellus odoratus (Schweinitz: Fries) Fries, being recorded for the first time in Tanzania; while the remaining one could be a new species. Further comprehensive studies need to be conducted in Kigoma miombo woodland to explore the macrofungi diversity to understand and document them. Key words: Craterellus, Kigoma, Miombo woodland, Tanzani
Cytotoxicity, antimicrobial and antioxidant activities of Boletus bicolor, A basidiomycetes mushroom indigenous to Tanzania
Boletus bicolor commonly known as coloured bolete is a basidiomyctes mushroom species widely used as a delicacy and its extract has been used traditionally to treat several human ailments in Tanzania. This study evaluates its extracts in order to provide a scientific foundation on the possible application in folk medicine system based on the biochemical evaluation. Standard microbes Bacillus subtilis and Candida albicans were used to test, the antifungal and antibacterial activity.  Cytotoxicity test was also done on the extracts using brine shrimp test. Besides, the extracts were also used to investigate for antioxidant activity using DPPH (1, 1-diphenyl-2-picrylhydrazyl radical). Quantitative analyses for ß-carotene, lycopene, total phenolic compounds and vitamin C contents were also determined using spectrophotometric assay at 515 nm. The study result revealed B. bicolor methanol extracts to exhibit positive antimicrobial activity against Bacillus subtilis forming an inhibition zone of up to 2.3 mm/2days while it had no effect on Candida albicans. It further portrayed relatively mild cytotoxic activity with the LC50 value of 113.75μg/ml. The phenolic compounds were recorded high up to 187.45 GAE mg/g, ß-carotene 15.7 mg/g, Lycopene 23.81 mg/g and Vitamin C content 5.09 mg/100g. Likewise the radical scavenging ability was also high and concentration dependent with maximum ability at 1 ml/100g and EC50 value of 0.046 mg/ml. The findings from this study supports the traditional medicinal use of this mushroom and envisage a purposeful thoroughly study for isolating the bioactive compounds, up-scaling and possible developments into nutraceutics
A Comparative Study of Antioxidant Activities between Fresh and Dry Mushrooms in the Genera Cantharellus and Afrocantharellus from Tanzania
Cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes their values and the effect of sun drying on their quality and quantity. Methanolic extracts of five Cantharellus and two Afrocantharellus species were investigated. The investigation used (1,1-diphenyl-2-picrylhydrazyl radical) DPPH as a substrate to determine radical scavenging abilities. Further quantitative analyses for carotenoids, flavonoid, total phenolic compounds and vitamin C content were done using spectrophotometric assay at 515 nm. Comparatively, fresh mushroom had higher vitamin C and Lycopene contents than their dry counterparts with β-carotene. Flavonoid and phenolic compounds were higher in dry forms than those in their fresh counterparts. Radical scavenging ability also varied with fresh forms depicting higher activity compared to dry forms. The variation was low in Afrocantharellus species (0.8% and 0.99%) while it was higher in Cantharellus species (24.12% and 7.52%). The highest ability was observed in fresh forms of Cantharellus pseudocibarius (EC50 < 0.14 mg/ml) while the least ability (EC50 = 0.4 mg/ml) was from dry form of Cantharellus rufopunctatus. This shows that studied mushrooms are rich in antioxidants and their quality and quantities are affected differently in both forms. Both dry and fresh mushrooms are potential sources of natural antioxidants. The portrayed high scav- enging ability by these mushrooms envisages promoting them into potential nutraceutics
Antiradical and antioxidant activities of methanolic extracts of indigenous termitarian mushroom from Tanzania
Termitomyces mushrooms grow symbiotically with termites. They are abundantly distributed in the country, mostly consumed and liked by people. However, their antiradical and antioxidants activities are not yet established. In this study, both qualitative and quantitative values of antiradical and antioxidant of crude methanolic extracts of six Termitomyces species (T. titanicus, T. aurantiacus, T. letestui, T. clypeatus, T. microcarpus and T. eurhizus) were investigated. The investigation used DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical as a substrate to determine both scavenging abilities and antiradical activities. Antioxidant was further analysed quantitatively for b-carotene, flavonoid content, total phenolic compounds and vitamin C content in the crude methanolic extracts using spectrophotometric assay at 515 hm. The result showed that they all exhibited scavenging ability and antiradical activity although the ability differed markedly among the species. The highest antiradical activity unit (EAU515) was from T. microcarpus (EAU515 1.48) followed by T. aurantiacus (EAU515 1.43) while the lowest was from T. eurhizus (EAU515 0.7). The scavenging power was also highest in T. microcarpus (EC50 < 0.1 mg/ml) followed by T. letestui (EC50 = 0.14 mg/ml); while T. eurhizus showed the least power (EC50 = 0.36 mg/ml). In quantitative analysis, T. microcarpus was also found having high content of phenols, Flavonoid, and b-carotene except lycopene and Vitamin C content which were high in T. aurantiacus and T. eurhizus respectively. Based on these results, all studied termitarian mushroom are good source of antioxidants while T. microcarpus could be considered as potential antiradicals of high profile thus thought for selection in preparation of mushroom-based nutraceutics. The results also endorse the continuing harvesting of these wild mushrooms for including them in our daily food for healthy diets. Â Keywords: Antioxidant, antiradical, Termitomyces, Termitarian, Tanzani
Antimicrobial Activities of Endophytic Fungal Crude Extracts Isolated from Cashew Tree (Anacardium occidentale)
This study presents the antimicrobial activities of endophytic fungal crude extracts isolated from leaves, stems and roots of cashew trees (Anacardium occidentale) which showed disease symptoms and those resistant from Fusarium wilt in Mtwara region. Sections of the cashew trees were made and cultured to isolate endophytes. Eight endophytes were isolated and characterized by using morphological and molecular markers. Neopestalotiopsis, Penicillium, Lasidioplodia and Daldinia sp isolated from resistant tree and Auxarthron and Aspergillus sp from diseased tree. Antimicrobial activities of the isolated endophytic fungal crude extracts were done against pathogenic Fusarium oxysporum and three human pathogens namely, Staphylococcus aureus, Escherichia coli, and Candida tropicalis. Results showed that all endophytic fungal crude extracts isolated from resistant plants and one from diseased plants exhibited positive antimicrobial activities against bacteria and fungus Candida tropicalis but they had no antifungal activity against Fusarium oxysporum. This study could contribute to the discovery and innovation of therapeutics. This study also implied that the resistance against Fusarium wilt disease might be caused by other unknown factors. More research work is recommended for establishing other possible factors including endophytic bacteria, biotic and abiotic factors that could contribute to resistance of cashew plants to Fusarium oxysporum.
Keywords: Antifungal; Phytopathology; Endophyte; Cashew nut diseas
A comprehensive study on Agaricus-like mushrooms from Mwalimu JK Nyerere Mlimani Campus, Tanzania
A 3 years survey was conducted from 2011 to 2014 during which 133 Agaricus-like mushrooms from different places in primary forests, fields and gardens of the University of Dar es Salaam, Mwalimu JK Nyerere Mlimani Campus were collected. Agaricus-like mushrooms are morphologically characterized by medium to large size basidiocarp on the central stalk that separates easily from the cap, free gills, presence of veil and chocolate brown basidiospores in mature specimens. Characterizing them using both macro-micromorphological features and molecular markers (ITS sequences), they were revealed to be 12 species belonging to two distinct genera Agaricus L. and Hymenagaricus H. The species Agaricus xanthodermus and one un-described were suspected poisonous, edibility of 3 species were known while the edibility of the rest were unknown. Based on the result finding, one Hymenagaricus and two Agaricus species are also proposed as novel species for scientific descriptions based on International Code of Nomenclature. Keywords: Agaricus, Hymenagaricus, Mushroom, University of Dar es Salaa
Antimicrobial Activities of Endophytic Fungi Secondary Metabolites from Moringa oleifera (Lam)
This study presents the antimicrobial activities of secondary metabolites of endophytic fungi isolated from a medicinal plant Moringa oleifera growing at the University of Dar es Salaam, Tanzania. Two endophytic fungi were identified, Nigrospora sp. from leaves, and Fusarium sp. from roots and seeds. The disc method was used in testing the antimicrobial activities of the crude extracts of endophytic fungi secondary metabolites against four human pathogens, namely, Bacillus substilis, Staphylococcus aureus, Escherichia coli, and Candida albicans. The results revealed that the crude extracts of endophytes secondary metabolites from leaves showed strong antimicrobial activities against two Gram positive bacteria and fungi with Minimum Inhibitory Concentrations (MICs) ranging from 0.016 mg/mL to 0.5 mg/mL, while from roots and seeds showed moderate antimicrobial activities with MIC ranging from 0.6 mg/mL to 1 mg/mL. Qualitative phytochemical analysis of the same extracts also revealed the presence of vital constituents potential for medicinal applications such as alkaloids, phenols, flavonoids, tannins, terpenoids, and saponins. This study demonstrated that secondary metabolites of endophytic fungi from Moringa oleifera possess important phytochemical and exhibit antimicrobial potential against the tested human pathogens which could contribute to the endeavours for new therapeutic inventions.Keywords: Antimicrobial activity; Endophytic fungi; Medicinal plants;Â Moringa oleifera
Identification of Tanzanian saprophytic edible mushrooms by amplification and sequencing of ITS/LSU regions of ribosomal RNA operon
In this study, ten wild saprophytic edible mushrooms samples, collected from Tanzania natural forests and planted trees, and their two domesticated forms were characterized by in-vitro/in-vivo amplification and sequencing of ITS/LSU regions. Mushroom genomic DNA was extracted by ZR Fungal/Bacterial DNA MniPrep Kit. ITS and LSU regions were amplified using ITS-4/ITS-5 and LR16/LROR primers, respectively and sequenced. The amplicons with messy sequences were cloned. For analyzing recombinant E. coli DH5α cells, colony PCR and sequencing were done using M13-F/M13-R primers. The studied mushrooms were identified as Amylosporus sp. IJ-2014, Polyporales sp., Polyporus tenuiculus, Pleurotus cystidiosus, Laetiporus sp. IJ-2014, Lentinus sajor-caju, Favolus roseus and Auricularia polytricha. The ITS-based phylogeny inferred by Neighbor-Joining method accommodated six genera under bootstrap support values of 100% with each genus consisting mushrooms of a single species. The LSU-based phylogeny inferred by Maximum Likelihood method accommodated nine genera with bootstrap support of ≥ 66% with some genera consisting mushrooms of different species. From these results, it is clear that both ITS and LSU markers successfully discriminated wild saprophytic edible mushrooms to their respective genera but ITS marker demonstrated the higher resolving power at the species level than LSU marker.Keywords: Saprophytic edible mushrooms, ITS, LSU, RNA opero
Characterization and Domestication of Wild Edible Mushrooms from Selected Indigenous Forests in Burundi
In Burundi, minimum work has been done to comprehensively identify and commercialize high yielding local mushrooms. The previous studies carried out on mushroom cultivation have focused on exotic strains. This is the first study undertaken on domestication of wild edible mushrooms from Burundi indigenous forests. Nine samples were collected from four protected areas and characterized using phenotypic and molecular markers. Germoplasm isolation through tissue culture techniques, spawn production and cultivation studies were also undertaken. Mushroom samples were identified as Pleurotus citrinopileatus, Lentinus squarrosulus, Hypholoma fasciculare, Laetiporus sulfureus, Macrolepiota dolichaula, Trametes polyzona, Amanita zambiana, Lactarius delicious and Amanita verna. Spawn production was successful in six of the nine collected species. Fruiting body production was successful for Pleurotus citrinopileatus, Lentinus squarrosulus, Hypholoma fasciculare and Trametes polyzona. Mushroom yield and biological efficiency of domesticated species varied among species and ranged from 15.3 to 30.6% and 41.2% to 81%, respectively. Macrolepiota dolichaula and Laetiporus sulfureus remained at the secondary mycelium stage while Amanita zambiana, Lactarius delicious and Amanita verna did not develop even the mother spawn. Burundi indigenous forests harbour wild edible mushrooms with potential for domestication. More research should be conducted to domesticate them for food and nutritional security. Keywords: Domestication; wild edible mushrooms; germplasm; spawn; Burundi indigenou
Complete genome sequence and epigenetic profile of Bacillus velezensis UCMB5140 used for plant and crop protection in comparison with other plant-associated Bacillus strains
The application of biocontrol biopesticides based on plant growth–promoting rhizobacteria (PGPR), particularly members of the genus Bacillus, is considered a promising perspective to make agricultural practices sustainable and ecologically safe. Recent advances in genome sequencing by third-generation sequencing technologies, e.g., Pacific Biosciences’ Single Molecule Real-Time (PacBio SMRT) platform, have allowed researchers to gain deeper insights into the molecular and genetic mechanisms of PGPR activities, and to compare whole genome sequences and global patterns of epigenetic modifications. In the current work, this approach was used to sequence and compare four Bacillus strains that exhibited various PGPR activities including the strain UCMB5140, which is used in the commercial biopesticide Phytosubtil. Whole genome comparison and phylogenomic inference assigned the strain UCMB5140 to the species Bacillus velezensis. Strong biocontrol activities of this strain were confirmed in several bioassays. Several factors that affect the evolution of active PGPR B. velezensis strains were identified: (1) horizontal acquisition of novel non-ribosomal peptide synthetases (NRPS) and adhesion genes; (2) rearrangements of functional modules of NRPS genes leading to strain specific combinations of their encoded products; (3) gain and loss of methyltransferases that can cause global alterations in DNA methylation patterns, which eventually may affect gene expression and regulate transcription. Notably, we identified a horizontally transferred NRPS operon encoding an uncharacterized polypeptide antibiotic in B. velezensis UCMB5140. Other horizontally acquired genes comprised a possible adhesin and a methyltransferase, which may explain the strain-specific methylation pattern of the chromosomal DNA of UCMB5140.The South African National Research Foundation (NRF), the joint NRF/COSTECH (Tanzanian Commission for Science and Technology), joint TIA (Technology Innovation Agency of South Africa)/COSTECHPhD and MSc student fellowship grants from Southern African Biochemistry and Informatics for Natural Products (SABINA, http://www.sabina-africa.org/) and Agroscope through its research program Microbial Biodiversity.http://link.springer.com/journal/2532021-07-10hj2020BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog