<b>Bioactive metabolites from <i>Trichoderma harzianum</i> and <i>Trichoderma longibrachiatum</i></b>

Abstract

The tea plant, Camellia sinensis (L.) O. Kuntze is an important crop in the agriculturally based economy of Kenya. Many diseases affect the tea plant but the most prevalent is armillaria root rot caused by the fungus Armillaria mellea. Compounds from the fermentation of Trichoderma species in different media were bioassayed against some selected gram-positive and gram-negative bacteria, fungi including Armillaria mellea, a yeast and a Mucor. Compounds obtained from T. harzianum, and T. longibrachiatum when cultured in various media were investigated individually for in-vitro antifungal and antibacterial activities by agar diffusion technique. Some of the compounds produced definite antifungal and antibacterial activities. 2-Phenylethanol (1) and tyrosol (2) obtained from T. harzianum are reported for the first time from Trichoderma species. The most active metabolite isolated from these strains was 6-n-pentyl-•pyrone (3), which showed the highest antifungal and antibacterial activity and completely inhibited the growth of Armillaria mellea fungus at a concentration of 200 ppm. Compound 4 (sorbicillin) exhibited moderate activity against the fungal test organisms.

Formation of 6-n-pentyl-2H-pyran-2-one (6-PAP) and other volatiles by different Trichoderma species

“…lycopersici , Fusarium verticilioides (moniliforme ), Phytophthora megasperma , Rhizoctonia solani , and Armillaria mellea (Al- Heeti and Sinclair 1988;Scarselletti and Faull 1994;Worasatit et al 1994;Poole et al 1998;Tarus et al 2003). In addition, it has been shown that 6-n-pentyl-2H-pyran-2-one can reduce the production of deoxynivalenol by Fusarium graminearum on agar medium (Cooney et al 2001).…”

“…These volatiles have been described for T. atroviride , T. aureoviride , T. harzianum , T. longibrachiatum , T. pseudokoningii, and T. viride, and their spectrum is characteristic for each strain as well as dependent on growth phase and nutritional, biological, and environmental conditions (Wheatley et al 1997;Bruce et al 2000;Tarus et al 2003;Nemčovič et al 2008;Stoppacher et al 2010;Polizzi et al 2011).…”

“…Other volatile metabolites derived from Trichoderma spp., which are involved in complex Trichoderma-plant pathogen interactions, have been mainly assigned to alcohols, ketones, alkanes, furans, and mono-and sesquiterpenes (Ghisalberti et al 1992;Mannina et al 1997;Wheatley et al 1997;Fiedler et al 2001;Tarus et al 2003;Lloyd et al 2005;Nemčovič et al 2008;Stoppacher et al 2010;Polizzi et al 2011). These volatiles have been described for T. atroviride , T. aureoviride , T. harzianum , T. longibrachiatum , T. pseudokoningii, and T. viride, and their spectrum is characteristic for each strain as well as dependent on growth phase and nutritional, biological, and environmental conditions (Wheatley et al 1997;Bruce et al 2000;Tarus et al 2003;Nemčovič et al 2008;Stoppacher et al 2010;Polizzi et al 2011).…”

Database on the taxonomical characterisation and potential toxigenic capacities of microorganisms used for the industrial production of food enzymes and feed additives, which do not have a recommendation for Qualified Presumption of Safety

“…1-phenyl-3-methylpyrazolones oxidoreductase mediators [297] aryl tetral226in lignans bioactive compounds [298] podophyllotoxin bioactive compounds [298] Trametes versicolor funatrol D bioactive compound [299] isodrimenediol sesquiterpenes (anticancer) [299] tramspiroins sesquiterpenes (anticancer) [299] triterpenes bioactive compounds [300] Database on potential toxigenic capacities of microorganisms used for industrial production 2,4-di-tert-butylphenol bioactive compound [310] 2,6,10-trimethylundeca-5,9-dienal bioactive compound [310] 2-phenylethanol bioactive compound [311] 6-pentyl-alpha-pyrone bioactive compound [312,313] 6-methyl-1,3,8-trihydroxyanthraquinone antifungal [308] 6-n-pentyl-a-pyrone bioactive compound [311] 6-pentyl-2H-pyran-2-one antifungal [308] alpha-cubebene bioactive compound [310] alpha-curcumene bioactive compound [310] anthraquinones antifungal [314] azaphilone antifungal [307,309] b-bisabolene bioactive compound [310] biformen (6CI) bioactive compound [310] butenolide antifungal [307,309] [318] gliotoxin bioactive compound [319] gliovirin bioactive compound [319,320] harzianic acid siderophore [321] harzianolide anti-phytopathogen [307,309,322] harzianopyridone anti-phytopathogen [307][308][309] harziphilone bioactive compound [318] hexahydrofarnesol bioactive compound …”

“…tandyukisins B-D (decalin derivative) cytotoxic [328] trichodenone A, B, C cytotoxic [329] trichodermin trichotecene toxin [319,330] trichodermol (detected in hydrolysed crude extracts) trichotecene toxin [331] trichorzin peptaibol [332] tyrosol bioactive compound [311] verticillol bioactive compound [310] viridiofungin A anti-phytopathogen [333] Trichoderma koningii 6, 4-oxopentyl-2H-pyran-2-one antifungal [334] 6-pentyl-pyranone antifungal [334] 7-O-methylkoninginin D (polyketide derivative) antimicrobial [335] alpha-aminoisobutyric acid [336] amino alcohol (peptaibols) [336] decanolactone antifungal [334] koninginins A, D, E, F, L, M phospholipase A 2 inhibitors [335,337,338] stigmasterol antifungal [334] trichodermaketones A-D (polyketide derivatives) antimicrobial [335,337] trichokonins (peptaibols) antimicrobial [339][340][341] Trichoderma longibranchiatum longibranchins (LGA I-V and LGB II-III) (peptaibols) biooactive compounds [342][343][344][345] Database on potential toxigenic capacities of microorganisms used for industrial production…”