Endophytes are microorganisms that live in the internal tissues of their host without causing any apparent disease symptoms. Instead, endophytes affect their hosts in a positive way including growth enhancement and protection against pathogens and feeding damage. Diaporthe phaseolorum var . caulivora , which was isolated from Neolitsea daibuensis, is a plant pathogen which infects soybean. D . phaseolorum var . caulivora was processed through solid-state fermentation, and its solid fermentate showed anti-inflammatory activity based on the preliminary screening. The phytochemistry and biological activities of D. phaseolorum var . caulivora have never been studied yet.
The 95% ethanolic extract of the solid fermentatation was partitioned and afforded n -butanol and water-soluble layers. Bioassay-guided fractionation of the active n -butanol-soluble layer of the solid fermentate of D. phaseolorum var . caulivora led to the isolation of one new geranylcyclohexenetriol , phaseoltoxin (1), two compounds isolated from nature source for the first time, 3-O-desmethyl phomentrioloxin (2)[1] and 2-hydroxyl peribysin A (3)[2], along with six known compounds, including one geranylcyclohexenetriol which is found specificlly in the genus, Diaporthe , phomentrioloxin (4), one sesquiterpene, peribysin A (5), two isocoumarins, mellein (6) and de- O -methyldiaporthin (7), one steroid, ergosterol peroxide (8), one amino acid, adenosine (9), and one fatty acid, palmitic acid (10). The structures of these compounds were elucidated by spectral analysis. The isolation of the active fractions is still in progress and the isolates are further evaluated with regard to anti-inflammatory activity.
References:
[1] Southgate EH, Pospech J, Fu J, Holycross DR, Sarlah D. Nat Chem 2016; 8: 922.
[2] Angeles AR, Waters SP, Danishefsky SJ. J Am Chem Soc 2008; 130: 13765-13770.