UPLC-Q-TOF-MS/MS Analysis of Seco-Sativene Sesquiterpenoids to Detect New and Bioactive Analogues From Plant Pathogen Bipolaris sorokiniana

Abstract

Seco-sativene sesquiterpenoids are an important member of phytotoxins and plant growth regulators isolated from a narrow spectrum of fungi. In this report, eight seco-sativene sesquiterpenoids (1–8) were first analyzed using the UPLC-Q-TOF-MS/MS technique in positive mode, from which their mass fragmentation pathways were suggested. McLafferty rearrangement, 1,3-rearrangement, and neutral losses were considered to be the main fragmentation patterns for the [M+1]+ ions of 1–8. According to the structural features (of different substitutes at C-1, C-2, and C-13) in compounds 1–8, five subtypes (A–E) of seco-sativene were suggested, from which subtypes A, B/D, and E possessed the diagnostic daughter ions at m/z 175, 189, and 203, respectively, whereas subtype C had the characteristic daughter ion at m/z 187 in the UPLC-Q-TOF-MS/MS profiles. Based on the fragmentation patterns of 1–8, several known compounds (1–8) and two new analogues (9 and 10) were detected in the extract of plant pathogen fungus Bipolaris sorokiniana based on UPLC-Q-TOF-MS/MS analysis, of which 1, 2, 9, and 10 were then isolated and elucidated by NMR spectra. The UPLC-Q-TOF-MS/MS spectra of these two new compounds (9 and 10) were consistent with the fragmentation mechanisms of 1–8. Compound 1 displayed moderate antioxidant activities with IC50 of 0.90 and 1.97 mM for DPPH and ABTS+ scavenging capacity, respectively. The results demonstrated that seco-sativene sesquiterpenoids with the same subtypes possessed the same diagnostic daughter ions in the UPLC-Q-TOF-MS/MS profiles, which could contribute to structural characterization of seco-sativene sesquiterpenoids. Our results also further supported that UPLC-Q-TOF-MS/MS is a powerful and sensitive tool for dereplication and detection of new analogues from crude extracts of different biological origins.

Comparative Antioxidant Activity and Untargeted Metabolomic Analyses of Sour Cherry Cultivars Based on Ultra-Performance–Time of Flight–Mass Spectrometry

“…Dark-flesh cultivars showed two times more antioxidant activity than light-flesh cultivars. The antioxidant content for the dark-flesh cultivars is approximately two-fold higher than the previously reported results [19] as well as possibly due to higher anthocyanin and total phenolic components [20].…”

“…UPLC–ToF–MS is a powerful tool with a shorter retention time [ 18 ]. We chose this technique as it is convenient for the detection of similar metabolites of lower concentration [ 19 ]. Further, the quantitative analysis of bioactive components (total phenols and antioxidants) was performed to correlate it with metabolic components.…”

Combination of ultra‐performance liquid chromatography‐quadrupole time‐of‐flight mass spectrometry and network pharmacology to reveal the mechanism of Shengyu Decoction for treating anemia

“…Now it has become a widely used and effective way to study the pharmacodynamic material basis of TCM [ 11 , 12 , 13 ]. UPLC‐quadrupole TOF‐MS (UPLC‐Q‐TOF‐MS) was widely used in the analysis of drugs, especially Chinese herbal medicines, due to its high separation ability, high sensitivity, and high resolution [ 14 , 15 , 16 ]. Therefore, in this study, UPLC‐Q‐TOF‐MS technology was used to analyze the chemical components of SYD and the components that entered the blood of anemic rats after oral administration.…”

Genome Mining Reveals the Biosynthesis of Sativene and Its Oxidative Conversion to seco-Sativene

“…2,3 Following the C14−C15 bond cleavage, a variety of tailoring steps, such as glycosylation, acetylation, isomerization, and esterification, have taken place to expand the chemical diversity of secosativene to over 100 family compounds. 4,5 Among them, a hemiacetal ring closure between C14 and C15 to reconstruct a new 6−5−6 hybrid pyran-bridged ring system, exemplified by prehelminthosporol (2), significantly represents the most universal but unusual modification reaction in seco-sativene.…”

“…A subgroup, namely, seco -sativene, constitutes the majority of sativene-type sesquiterpenoids. The seco -sativenes possess a bicyclo[3.2.1]­octane (6–5 ring system) formed via the C14–C15 bond cleavage of sativene (Figure A). , Following the C14–C15 bond cleavage, a variety of tailoring steps, such as glycosylation, acetylation, isomerization, and esterification, have taken place to expand the chemical diversity of seco -sativene to over 100 family compounds. , Among them, a hemiacetal ring closure between C14 and C15 to reconstruct a new 6–5–6 hybrid pyran-bridged ring system, exemplified by prehelminthosporol ( 2 ), significantly represents the most universal but unusual modification reaction in seco -sativene.…”