Destruxin B2 is a cyclic hexadepsipeptide mycotoxin that has been found in M. anisopliae and has antiviral, insecticidal, and phytotoxic activities.1,2,3 It inhibits secretion of hepatitis B virus surface antigen (HBsAg) by Hep3Bcells expressing hepatitis B virus (HBV) DNA (IC50 = 1.3 μM).1 Destruxin B2 is toxic to Sf9 insect cells in an electric cell-substrate impedance sensing (ECIS) test with a 50% inhibitory concentration (ECIS50) value of 92 μM.4 It is also phytotoxic to B. napus leaves.3 |1. Yeh, S.F., Pan, W., Ong, G.-T., et al. Study of structure-activity correlation in destruxins, a class of cyclodepsipeptides possessing suppressive effect on the generation of hepatitis B virus surface antigen in human hepatoma cells. Biochem. Biophys. Res. Commun. 229(1), 65-72 (1996).|2. Male, K.B., Tzeng, Y.-M., Montes, J., et al. Probing inhibitory effects of destruxins from Metarhizium anisopliae using insect cell based impedance spectroscopy: Inhibition vs chemical structure. Analyst 134(7), 1447-1452 (2009).|3. Buchwaldt, L., and Green, H. Phytotoxicity of destruxin B and its possible role in the pathogenesis of Alternaria brassicae. Plant Pathol. 41(1), 55-63 (1992).
2α,3α,24-Trihydroxyurs-12-en-28-oic acid, a triterpenoid phytoalexin, shows antifungal activity against the fungus mentioned. It also shows in vitro cytotoxic activity against tumor cell lines including PLC,Hep3B,HepG2,HeLa,SW480,MCF-7 and Bel7402.
Manassantin B is a potent inhibitor of NF-κB activation by the suppression of transciptional activity of RelA p65 subunit of NF-κB. It also possesses anti-EBV lytic replication activity. Manassantin B inhibits interleukin-6-induced signal transducer and activator of transcription 3 activation in Hep3Bcells, it has potential as a potent anti-inflammatory drug for use in pathological processes such as sepsis or acute lung injury. Manassantin B exerts antifibrotic activity in HSC-T6 cells, in part, via inhibition of cell proliferation and decrease of collagen production.