Analysis of radical scavenging active components in the fermented mycelia of Ophiocordyceps formosana

Abstract

The rates of 1,1-diphenyl-2-picryhydrazyl (DPPH)-free radical scavenging and hydroxyl radical eliminating were employed as indexes to qualitatively and quantitatively analyse the radical scavenging activity of the extracts with different solvents from fermented mycelia of Hirsutella huangshanensis RCEF0868, the anamorph of Ophiocordyceps formosana (FMOF). The results showed that both the aqueous extract and the methanol extract had significant radical scavenging activity. The half maximal inhibitory concentrations (IC50) of the aqueous extract on DPPH-free radical and hydroxyl radical are 0.85 and 1.37 mg/mL, respectively, while the IC50 of methanol extract is 1.23 and 2.91 mg/mL, respectively. The combined liquid chromatography-diode array detector-high resolution mass spectrometer(HRMS) analysis and activity determination revealed that the molecular formulas of three radical scavengers in aqueous extract were C6H14O6(1), C14H17N5O8(2) and C20H33N5O9(3). In addition to the compound 1, the methanol extract had another three radical scavengers as C30H22O11(4), C30H22O10(5) and C30H18O10(6). All the six kinds of components exhibited the DPPH radical scavenging activity, and compounds 1, 4 and 5 also showed the hydroxyl radical eliminating activity at the same time. By querying the database of natural products and reference to the relevant reports, compound 3 may be a new entity. The others were respectively cordycepic acid, succinoadenosine, 4α-oxyrugulosin, rugulosin and skyrin and, among them, succinoadenosine and 4α-oxyrugulosin were found in entomogenous fungi for the first time.

Antioxidant Activity and Hepatoprotective Effect of Exopolysaccharides From CultivatedOphiocordyceps SinensisAgainst CCl4-Induced Liver Damages

“…IC 50 values of hydroxyl inhibitory activity of aqueous and methanol extracts of mycelia of Ophiocordyceps formosana were 1.23 mg/mL and 2.91 mg/mL, respectively. 16 In comparison with the antioxidant activity of other Cordyceps species collected from different places, the ABTS radical scavenging activity of EPS from O. sinensis in this study was higher than that of the species reported by Shamar et al 15 and the species (except C. sinensis ) collected in Vietnam reported by Phuong-Tham Ho-Thi et al 14…”

Intertwined Biosynthesis of Skyrin and Rugulosin A Underlies the Formation of Cage-Structured Bisanthraquinones

“…This is unique and explains why 2 appeared exclusively in the 5-exposed cultivation of both AO-rugGH and SC-RC01-rugGH cotransformants, rather than the cocultures of AO-rugH plus AO-rugG, or SC-BJ5464-rugH with SC-RC01-rugG, transformants (Figure 5). Such a cascade mechanism explains why, in nature, rugulosin A ( 2) is normally produced together with skyrin (1), 21,23,24,26,27 but not vice versa. 18,20 In alignment with the observation, the genomes of 1and 2-coproducing fungi contain the rugG and rugH homologues linked closely or contiguously (Tables S13−S16 and Figure S10), whereas no rugH homologue was found in that of Cyanodermella asteris (Figure S11), which generates 1 without yielding 2.…”

“…The potent bioactivities and unique structures of 1 and 2 have spurred their chemical synthesis. − Surprisingly, the knowledge regarding their biosynthesis remains limited to the isotope feeding tests (performed half a century ago , ) and the bioinformatic prediction of the skyrin ( 1 ) biosynthetic cluster that awaits experimental verification . Skyrin ( 1 ) and rugulosin A ( 2 ) have been individually isolated from a broad range of taxonomically distant fungi (e.g., 1 from Cyanodermella asteris , Talaromyces islandicus , Dermocybe icterinoides , and T. rugulosus ; 2 from T. rugulosus , Ophiocordyceps formosana , Chrysoporthe sp. SNB-CN74, and Phialocephala scopiformis ).…”

Cynaropicrin- and chlorogenic acid-rich extracts easily prepared from Cynara cardunculus var. scolymus: Antioxidant and antigenotoxic properties

“…It was expected that both fractions would display similar DNA protective properties assessed by this method since their radical scavenging activity was similar against DPPH (Table 3) and DNA single strand breaks in the DNA topology assay are due to the radical (hydroxyl radical) generated by FeSO 4 (Ševčovičová et al, 2015). The differences may be due to different scavenging potential against different radicals as it has been previously shown with skyrin, which exhibited scavenging activity against DPPH and no activity against hydroxyl radical (Li et al, 2017). Moreover, as iron-chelating activity would avoid reactivity of Fe 2+ , and hence DNA damage, DNA protecting activity might also be due to metal-chelating activity, besides scavenging of radicals.…”