ABSTRACT
Trichothecene mycotoxins are recognized as highly bioactive compounds that can be used in the design of new useful bioactive molecules. In Trichoderma brevicompactum, the first specific step in trichothecene biosynthesis is carried out by a terpene cyclase, trichodiene synthase, that catalyzes the conversion of farnesyl diphosphate to trichodiene and is encoded by the tri5 gene. Overexpression of tri5 resulted in increased levels of trichodermin, a trichothecene-type toxin, which is a valuable tool in preparing new molecules with a trichothecene skeleton. In this work, we developed the hemisynthesis of trichodermin and trichodermol derivatives in order to evaluate their antimicrobial and cytotoxic activities and to study the chemo-modulation of their bioactivity. Some derivatives with a short chain at the C-4 position displayed selective antimicrobial activity against Candida albicans and they showed MIC values similar to those displayed by trichodermin. It is important to highlight the cytotoxic selectivity observed for compounds 9, 13, and 15, which presented average IC50 values of 2 µg/mL and were cytotoxic against tumorigenic cell line MCF-7 (breast carcinoma) and not against Fa2N4 (non-tumoral immortalized human hepatocytes).
Subject(s)
Trichodermin/analogs & derivatives , Animals , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/metabolism , Antifungal Agents/pharmacology , Candida albicans/drug effects , Cell Line , Female , Hepatocytes/drug effects , Humans , MCF-7 Cells , Mycotoxins/pharmacology , Rabbits , Trichoderma/enzymology , Trichoderma/genetics , Trichoderma/metabolism , Trichodermin/chemical synthesis , Trichodermin/chemistry , Trichodermin/pharmacologyABSTRACT
The endophytic fungus strain 0248, isolated from garlic, was identified as Trichoderma brevicompactum based on morphological characteristics and the nucleotide sequences of ITS1-5.8S- ITS2 and tef1. The bioactive compound T2 was isolated from the culture extracts of this fungus by bioactivity-guided fractionation and identified as 4ß-acetoxy-12,13- epoxy-Δ(9)-trichothecene (trichodermin) by spectral analysis and mass spectrometry. Trichodermin has a marked inhibitory activity on Rhizoctonia solani, with an EC50 of 0.25 µg mL(-1). Strong inhibition by trichodermin was also found for Botrytis cinerea, with an EC50 of 2.02 µg mL(-1). However, a relatively poor inhibitory effect was observed for trichodermin against Colletotrichum lindemuthianum (EC50 = 25.60 µg mL(-1)). Compared with the positive control Carbendazim, trichodermin showed a strong antifungal activity on the above phytopathogens. There is little known about endophytes from garlic. This paper studied in detail the identification of endophytic T. brevicompactum from garlic and the characterization of its active metabolite trichodermin.
Subject(s)
Antifungal Agents/pharmacology , Endophytes/chemistry , Garlic/microbiology , Trichoderma/chemistry , Trichodermin/pharmacology , Antifungal Agents/isolation & purification , Botrytis/drug effects , Cluster Analysis , Colletotrichum/drug effects , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Endophytes/classification , Endophytes/isolation & purification , Mass Spectrometry , Microbial Sensitivity Tests , Molecular Sequence Data , Peptide Elongation Factor 1/genetics , Phylogeny , RNA, Ribosomal, 5.8S/genetics , Rhizoctonia/drug effects , Sequence Analysis, DNA , Trichoderma/classification , Trichoderma/isolation & purification , Trichodermin/isolation & purificationABSTRACT
The endophytic fungus strain 0248, isolated from garlic, was identified as Trichoderma brevicompactum based on morphological characteristics and the nucleotide sequences of ITS1-5.8SITS2 and tef1. The bioactive compound T2 was isolated from the culture extracts of this fungus by bioactivity-guided fractionation and identified as 4β-acetoxy-12,13-epoxy-Δ9-trichothecene (trichodermin) by spectral analysis and mass spectrometry. Trichodermin has a marked inhibitory activity on Rhizoctonia solani, with an EC50 of 0.25 µgmL-1. Strong inhibition by trichodermin was also found for Botrytis cinerea, with an EC50 of 2.02 µgmL-1. However, a relatively poor inhibitory effect was observed for trichodermin against Colletotrichum lindemuthianum (EC50 = 25.60 µgmL-1). Compared with the positive control Carbendazim, trichodermin showed a strong antifungal activity on the above phytopathogens. There is little known about endophytes from garlic. This paper studied in detail the identification of endophytic T. brevicompactum from garlic and the characterization of its active metabolite trichodermin.(AU)
Subject(s)
Antifungal Agents/pharmacology , Endophytes/chemistry , Garlic/microbiology , Trichoderma/chemistry , Trichodermin/pharmacology , Antifungal Agents/isolation & purification , Botrytis/drug effects , Cluster Analysis , Colletotrichum/drug effects , DNA, Fungal/chemistry , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal/chemistry , Endophytes/classification , Endophytes/isolation & purification , Mass Spectrometry , Microbial Sensitivity Tests , Molecular Sequence Data , Peptide Elongation Factor 1/genetics , Rhizoctonia/drug effects , Sequence Analysis, DNA , Trichoderma/isolation & purification , Trichodermin/isolation & purificationABSTRACT
The endophytic fungus strain 0248, isolated from garlic, was identified as Trichoderma brevicompactum based on morphological characteristics and the nucleotide sequences of ITS1-5.8SITS2 and tef1. The bioactive compound T2 was isolated from the culture extracts of this fungus by bioactivity-guided fractionation and identified as 4β-acetoxy-12,13-epoxy-Δ9-trichothecene (trichodermin) by spectral analysis and mass spectrometry. Trichodermin has a marked inhibitory activity on Rhizoctonia solani, with an EC50 of 0.25 µgmL-1. Strong inhibition by trichodermin was also found for Botrytis cinerea, with an EC50 of 2.02 µgmL-1. However, a relatively poor inhibitory effect was observed for trichodermin against Colletotrichum lindemuthianum (EC50 = 25.60 µgmL-1). Compared with the positive control Carbendazim, trichodermin showed a strong antifungal activity on the above phytopathogens. There is little known about endophytes from garlic. This paper studied in detail the identification of endophytic T. brevicompactum from garlic and the characterization of its active metabolite trichodermin.