No abstract

Five new resorcylic acid lactones (RALs) hispidulactones A-E (1, 4, 5, 8, and 9), a new natural product (2), and four known ones (3, 6, 7, and 10) with different ring systems were isolated from the desert plant endophytic fungus Chaetosphaeronema hispidulur. The new compounds were characterized by NMR data, CD spectra, and X-ray experiment. The new natural product (2) displayed strongly biological effects on the seedlings growth of Arabidopsis thaliana, Digitaria sanguinalis, and Echinochloa crusgalli with a dose-dependent relationship. Compounds 1, 2, and 6 were also tested cytotoxic activities against three cancer cell lines HCT116, Hela, and MCF7 and only did the new natural product (2) display biological activities with IC values at 54.86 ± 1.52, 4. 90 ± 0.02, and 20.04 ± 4.00 μM, respectively, whereas the IC values of the positive control cis-platinum were 11.36 ± 0.42, 3.54 ± 0.12, and 14.32 ± 1.01 μM, respectively.

Nine new epipoly(thiodioxopiperazine) (ETP) analogues, chetocochliodins A-I (1−9), along with two known ones, chetoseminudins E and C (10 and 11), were purified from the fungus Chaetomium cochliodes. The planar structures and absolute configurations of these new compounds were determined by extensive NMR spectroscopic analysis, CD spectra, and chemical reactions. Shielding effects from the indole on the 3-SCH 3 /3-OCH 3 /3-OCH 2 -groups facilitated the determination of relative configuration of the analogues. Compound 9 was cytotoxic, suggesting the importance of the sulfide bridge for the diketopiperazine bioactivities.

No abstract

Campylobacter is a leading causative pathogen of acute bacterial gastroenteritis among humans. Contaminated chicken products are regarded as major sources of human infection. The flagellar capping protein (FliD), which plays important roles in colonization and adhesion to the mucosal surface of chicken caeca, is conserved among Campylobacter jejuni strains. In this study, the recombinant C. jejuni FliD protein was expressed, purified, and used as a coated protein to examine the prevalence of C. jejuni antibodies in chickens. The anti-FliD antibody was prevalent among chicken serum samples taken from different farms in the diverse regions of Jiangsu Province by using ELISA assay. The Campylobacter antibody was present in culture-negative chickens. No strong dose–response relationships were observed between serum FliD antibody levels and Campylobacter cultural status. These results provide a basis for further evaluating FliD as a vaccine candidate for broiler chickens or for examining host–C. jejuni interactions, with implications for improving food safety.