Fulvanines J-K, two rare lactam pyrrole alkaloids from Hemerocallis fulva.

Two rare jatropham lactam derivatives, named as fulvanines J-K (1-2), together with six known pyrrole alkaloids, 5,5'-oxydi(3-methyl-3-pyrrolin-2-one) (3), (-)-5-hydroxy-3-methyl-3-pyrrolin-2-one (jatropham) (4), (±)-5-O-methyljatropham (5), perlolyrine (6), butyl-2-formyl-5-(hydroxymethyl)-1H-pyrrole-1-butanoate (7), and hemerocallisamine II (8), were isolated from the flower of Hemerocallis fulva. Their structures were elucidated on the basis of spectroscopic methods and compared with the NMR spectra data in the literature. All compounds were evaluated for their anti-complementary activity in vitro, and compounds 1, 4, and 6 exhibited anti-complement effect with CH50 values from 0.61 to 1.42 mM.

A new macrocyclic spermidine alkaloid from the aerial part of Hyssopus cuspidatus Boriss.

Hyssopus cuspidatus Boriss. grows in Xinjiang, China. A new macrocyclic spermidine alkaloid, namely hyssopusizine (1), along with sixteen known compounds were isolated and identified from the aerial parts of H. cuspidatus. Their structures were elucidated on the basis of spectroscopic data and comparison with the literature. Among them, fifteen compounds were isolated from H. cuspidatus for the first time. The absolute configuration of compound 1 was established by comparing the calculated and experimental ECD spectroscopic data. All isolated compounds were tested for their antioxidant and antimicrobial activities. Among them, compound 10 exhibited significant effects on ABTS free-radical scavenging activity with an IC50 value of 15.6 µM. Compounds 5-7 exhibited potent antioxidant activities against ABTS and DPPH. Most compounds exhibited moderate antimicrobial activities. Hyssopusizine (1) is the first macrocyclic spermidine alkaloid discovered from the Hyssopus genus.

Megastigmane sesquiterpenoids from whole plants of Viola kunawurensis.

Investigation on the chemical constituents of Viola kunawurensis resulted in the isolation of seven undescribed megastigmane sesquiterpenoids including four bicyclic megastigmane glucosides, kunawuronoside A-D, two megastigmane glucosides, kunawuronoside E-F, and a megastigmane, kunawurone A, together with ten known megastigmane sesquiterpenoids. Their structures were established by comprehensive 1D, 2D-NMR and HRESIMS analyses, and their absolute configurations were determined by comparing their calculated ECD data with the experimental ones. Evaluations of the anti-inflammatory activity revealed that kunawuronoside A-D and compounds 14-15 inhibited COX-2 expression with inhibition rates ranging from 36.7% to 58.5%, while the NO production induced by lipopolysaccharide (LPS) was suppressed by the kunawuronoside A-D in a dose-dependent manner in RAW264.7 macrophage cell line.

Non-volatile compounds of Hyssopus cuspidatus Boriss and their antioxidant and antimicrobial activities.

Hyssopus cuspidatus is a famous spice and an aromatic vegetable. Few information could be available concerning its non-volatile chemical composition and bioactivities. Preliminary bioactive evaluations on the crude ethanol extract and its four fractions disclosed that the ethyl acetate fraction (EAF) exhibited antioxidant and antimicrobial bioactivities. LC-MS/MS analysis of EAF helped to identify sixty-four compounds, and phenolic compounds were the dominant components. Systematic separation and purification of EAF led to the isolation of thirty-four compounds. Six compounds were identified to be new and eighteen compounds were discovered from H. cuspidatus for the first time. Rosmarinic acid, methyl rosmarinate, butyl rosmarinate and salvigenin were the major components of EAF and their contents were determined. Most of isolated compounds exhibited significant or moderate antioxidant and antimicrobial activities. This research supported the edible application of H. cuspidatus and disclosed the potency of it as a natural antioxidant and antimicrobial food additive.

Dynamic metabolic and transcriptomic profiling reveals the biosynthetic characteristics of hydroxycinnamic acid amides (HCAAs) in sunflower pollen.

Sunflower pollen is a natural nutritious food with a long history and multiple functions, however, the main chemical components apart from flavonoids and their biosynthesis processes have not been thoroughly investigated. In this study, seven hydroxycinnamic acid amides (HCAAs) (1-7) abundant in sunflower pollen were isolated and identified as one type of the pollen's main chemicals. For a comprehensive understanding of HCAA biosynthesis in Helianthus annuus flowers, RNA-seq, metabolomics, and key genes related to biosynthesis in the sunflower were studied. A large number of compounds at different sunflower growth stages (the 7th, 14th, 21st, and 28th days) and high expression levels of related genes in the transcriptome were detected. A molecular network was constructed to clarify the synthetic pathway of HCAAs, which revealed high transcriptional levels of spermidine hydroxycinnamoyl transferase genes (HaSHT2795 and HaSHT2436) in 14-21-days-old flowers. HaSHT2795 enzymes catalyze tri-coumaroylspermidine formation, and virus-induced gene silencing to inhibit HaSHT2795 and HaSHT2436 could significantly reduce the synthesis of hydroxycinnamic acid amides in sunflower pollen. HCAAs were inferred to be related to the formation of pollen walls and the health effects of pollen. Analyzing HCAA biosynthesis and accumulation in H. annuus pollen will be helpful to understand the functions of HCAAs in the development of pollen and its nutritional value.

Sesquiterpenoids from the seeds of Sarcandra glabra and the potential anti-inflammatory effects.

Five new sesquiterpenoids, including two linderanes (1-2) and three eudesmanes (3-5) were isolated from the seeds of Sarcandra glabra. Their structures and relative configurations were established by spectroscopic data analysis. 1 was a rare linderane derivative having an 18-membered triester ring which is a common characteristic in linderane dimers. Compounds 1-5 were investigated for their inhibitory effects on NO production in LPS-induced macrophages and 1 showed moderate bioactivity.