Plant growth-promoting activities of bacterial endophytes isolated from the medicinal plant Pairs polyphylla var. yunnanensis.

Pairs polyphylla var. yunnanensis (Paris L.) is a valuable medicinal plant used in traditional Chinese medicine. The market demand for P. polyphylla has increased over time, but it has slow growth and a low natural propagation rate. Endophytic bacteria are bioactive microorganisms that form a mutualistic relationship with host plants in long-term coordinated evolution, and they can promote the growth and accumulation of effective components in host plants. The aims of this study were to identify endophytic bacteria of P. polyphylla and to characterize their properties in promoting plant growth. A total of 10 endophytic bacteria were isolated from rhizomes of P. polyphylla. The isolated endophytes exhibited a variable capacity for indole acetic acid production, phosphate solubilization and nitrogen fixation. To investigate the effects of the endophytes on plant growth, four endophyte strains, G5, J2, G20, and Y2, were selected to compare their ability to promote plant growth. The results indicated that microbial endophytes isolated from P. polyphylla rhizomes play a vital role in improving P. polyphylla plant growth and could be used as inoculants to establish a sustainable crop production system.

Chemical Constituents of Endophytic Fungus Aconitum Transsectum from Alternaria Solani / 中国药师

Objective: To study the chemical constituents of endophytic fungus Alternaria solani from Aconitum transsectum. Methods: The compounds were isolated and purified by column chromatography , and their structures were elucidated based on the spectroscopic analysis (1H-NMR, 13C-NMR and MS).Results:Totally 15 compounds were isolated from A.solani and characterized as 20-hydroxyl-ergosta-4,6,8(14),22-tetraen-3-one(1),ergone(2),stellasterin(3),episterol(4),ergosterol peroxide(5),cyclo(D)-Pro-(D)-Leu(6),cyclo-(L-Val-L-Pro)(7),cyclo-(S-Pro-S-Ile)(8),tentoxin(9),porrotoxin(10),7-dehydroxyl-zinniol(11),zinniol (12),8-zinniol methyl ether (13),3-methoxy-4-methyl-5-(3′,3′-dimethylallyloxy)-2-methoxymethyl benzoic acid (14) and pseudo-monas aeruginosa H2-sesquiterpene lactone (15).Conclusion: Totally 15 compounds are isolated from endophytic fungus Alternaria solani, and compounds 2-10 and 12-15 are isolated for the first time .

Studies on Diterpenoid Alkaloids in Aconitum Transsectum / 中国药师

Objective:To study the chemical constituents in the roots of Aconitum transsectum. Methods:The compounds were i-solated and purified by column chromatography on the columns of silica gel, Al2 O3 and Sephadex LH-20, and their structures were elu-cidated on the basis of spectroscopic evidence ( MS and NMR) . Results:Totally 12 compounds were isolated from A. transsectum, and characterized as yunaconitine (1), indaconitine (2), crassialine A (3), 8-deacetylyunaconitine (4), talatisamine (5), chasma-conitine (6), 14-acetyltalatisamine (7), vilmoraconitine (8), sachaconitine (9), 14-acetylsachaconitine (10), acoforestinine (11) and vilmorrianine C (12). Conclusion:Compounds 8-11 are obtained from A. transsectum for the first time.

Study on Diterpenoid Alkaloids from the Roots of Aconitum Straminiflorum / 中国药师

Objective:To study the chemical constituents of Aconitum straminiflorum. Methods:The air-dried roots of A. stra-miniflorum were powdered and extracted three times with 90% ethonal under reflux. After the removal of the solvent under reduced pressure,the crude extract was dissolved in 1. 5% HCl solution(7 L). The acidic solution was basified to pH 9. 0 with ammonia (25%)and extracted with CHCl3 to obtain crude extract of total alkaloids after the removal of CHCl3 . The compounds were isolated and purified by column chromatography and identified based on spectral analysis( MS,1 H-üMR and 13 C-üMR). Results:Totally 7 compounds were isolated from A. straminiflorum,and characterized as aconosine(1),13-deoxyludaconitine(2),dolaconine(3), ezochasmanine(4),talatisamine(5),scopaline(6)and cammaconine(7),respectively. Conclusion:Seven diterpenoid alkaloids are isolated from A. Straminiflorum for the first time.