Anticandida Agents from a Tanzanian Plant Albizia anthelmintica

• Published in: Journal of the Chinese Chemical Society (Taipei) Vol. 62; no. 8; pp. 669 - 674
• Main Authors: Runyoro, Deborah K. B., Joseph, Cosam C., Ngassapa, Olipa D., Darokar, Mahendra P., Srivastava, Santosh K., Matee, Mecky I. N., Wright, Colin W.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.08.2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Albizia anthelmintica; Anticandida agents; Echinocystic acid; Synergistic; Triterpenoid saponins
• ISSN: 0009-4536; 2192-6549
• DOI: 10.1002/jccs.201500161

Candidiasis is one of the most frequent opportunistic infections in individuals with severe immunosupression and further development of resistance against the available antifungal drugs has created an alarming situation. This requires intensive drug discovery to develop new, more effective, affordable and accessible antifungal agents possessing novel modes of action. Albizia anthelmintica, which is ethno medically used to treat vaginal candidiasis in the Morogoro and coastal regions of Tanzania, on activity guided fractionation and subsequent purification resulted in the isolation and characterization of an isomer of methyl cyclitol (1) and six echinocystic acid saponins (2–7). Saponins 6 and 7 are new and being reported for the first time from nature. Among all the isolated compounds, 3‐O‐[α‐L‐arabinopyranosyl (1→2)][α‐L‐arabinopyranosyl (1→6)]‐2‐acetamido‐2‐deoxy‐β‐D‐glucopyranosyl echinocystic acid (4), 3‐O‐[α‐L‐arabinopyranosyl (1→2)] [α‐L‐arabinopyranosyl (1→6)]‐2‐amino‐2‐deoxy‐β‐D‐glucopyranosyl echinocystic acid (6) and 3‐O‐[β‐D‐glucopyranosyl (1→3)] [α‐L‐arabinopyranosyl (1→2)] [α‐L‐arabinopyranosyl (1→6)]‐2‐amino‐2‐deoxy‐β‐D‐glucopyranosyl echinocystic acid (7) and their combinations were active against the various strains of C. albicans with MICs ranging from 12.5 to 125 μg/ml. Gauge including magnetically induced current densities have been calculated at the DFT level for evaluating several shielding based ring current models showing why those models should not be used.