Cultivo consorciado do cafeeiro (coffea arabica L.) e cultivares da nogueira-macadâmia (Macadamia integrifolia maiden e betche) sob os regimes sequeiro e irrigado

Pós-graduação em Agronomia (Agricultura) - FCA

Desempenho de unidades de pré-limpeza de frutos de macadâmia (M. integrifolia)

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Reguladores vegetais na emergência e no desenvolvimento de plantas de macadâmia (Macadamia integrifolia Maiden & Betche)

Pós-graduação em Ciências Biológicas (Botânica) - IBB

Cytotoxic steroidal saponins from the rhizomes of Tacca integrifolia

Three new steroid saponins (3beta,25R)-spirost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)-6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (1), (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (3), and (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)-6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (5), as well as the new pregnane glycoside (3beta,16beta)-3-{[6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranosyl]oxy}-20-oxopregn-5-en-16-yl (4R)-5-(beta-D-glucopyranosyloxy)-4-methylpentanoate (6), were isolated from the rhizomes of Tacca integrifolia together with two known (25R) configurated steroid saponins (3beta,25R)-spirost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (2) and (3beta,22R,25R)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl 6-deoxy-alpha-L-mannopyranosyl-(1-->2)-[6-deoxy-alpha-L-mannopyranosyl-(1-->3)]-beta-D-glucopyranoside (4). The cytotoxic activity of the isolated compounds was evaluated in HeLa cells and showed the highest cytotoxicity value for compound 2 with an IC(50) of 1.2+/-0.4 muM. Intriguingly, while compounds 1-5 exhibited similar cytotoxic properties between 1.2+/-0.4 (2) and 4.0+/-0.6 muM (5), only compound 2 showed a significant microtubule-stabilizing activity in vitro.

Der Brodbaum (Artocarpus incisa L. fil. und integrifolia L. fl.)

Vom Dr. H. Karsten

Tacca integrifolia - Tacca cristata

AR