title: Bioactive potential of endophytic Myrothecium sp. isolate M1-CA-102, associated with Calophyllum apetalum.
abstract: BACKGROUND
  Endophytes colonizing medicinal plants are diverse, constituting a rich bioresource for novel natural products.
  
  
  OBJECTIVE
  Myrothecium sp. isolate M1-CA-102 was the most promising among the 16 Myrothecium isolates screened. The bioactive potential of the crude extract from the Calophyllum apetalum Willd. endophytic Myrothecium sp. (Alb. & Schwein.) Ditmar (Incertae sedis) isolate M1-CA-102 and its thin layer chromatography (TLC) fractions were screened based on antioxidant, anti-inflammatory, antimicrobial activities, and cytotoxicity.
  
  
  METHODS
  The antioxidant activity was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging capacities. Further, 15-lipoxygenase (15-LOX) and human cyclooxygenase-2 (COX-2) inhibition were assessed at different concentrations (25, 50, and 100 μg/mL for the crude extract, 5, 25, and 50 μg/mL for the TLC fractions). DNA-nicking assay as an indicator of the capacity of extracts to scavenge hydroxyl radical was recorded at a concentration of 50 μg/mL. Cell cytotoxicity was recorded by colorimetric 3-(4,5-dimethylthylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Antibacterial (Bacillus subtilis) and anti-Candida (Candida albicans) assays were performed by the microdilution method.
  
  
  RESULTS
  The DPPH and ABTS IC50 values of M1-CA-102 extract were 10 and 6 μg/mL compared with 6.1 and 7.03 μg/mL for the positive control quercetin. The cytotoxicity IC50 value of M1-CA-102 extract was 37 μg/mL, while the M-I TLC fraction was 21 μg/mL. The M1-CA-102 extract gave an IC50 value of 58 and 8 μg/mL for 15-LOX and COX-2, respectively. The MIC values for antimicrobial activity for M1-CA-102 extract ranged from 35 to 54 μg/mL, while for the TLC fractions, it ranged from 91 to 515 μg/mL.
  
  
  CONCLUSIONS
  The results indicate that Myrothecium M1-CA-102 isolated from C. apetalum is a potential source of natural metabolites of pharmaceutical importance.
authors.affiliation: Department of Studies in Biotechnology, University of Mysore , Manasagangotri, Mysore, Karnataka , India.
authors.forename: Karmakar
authors.initials: K
authors.lastname: Ruma
authors.forename: Kumar
authors.initials: K
authors.lastname: Sunil
authors.forename: Harischandra Sripathy
authors.initials: HS
authors.lastname: Prakash
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology; D001688:Biological Products / Q000302:isolation & purification* / Q000494:pharmacology; D029759:Calophyllum; D052246:Cyclooxygenase 2 Inhibitors / Q000302:isolation & purification / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D060026:Endophytes / Q000302:isolation & purification*; D006367:HeLa Cells; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D010936:Plant Extracts / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001688:Biological Products; D052246:Cyclooxygenase 2 Inhibitors; D010936:Plant Extracts
keywords: 15-LOX; Antimicrobial; COX-2; antioxidant; cytotoxicity