Growth and Oleanolic Acid Accumulation of Polyscias fruticosa Cell Suspension Cultures.

BACKGROUND: Oleanolic acid is an oleanane triterpene found in many plant species all over the world. This compound is also a major saponin in leaves of Polyscias fruticosa and possesses several promising pharmacological activities, such as hepatoprotective effects, and antiinflammatory, antioxidant, or anticancer activities. OBJECTIVE: The objective of the present work is to establish cell suspension culture of P. fruticosa, investigate the influence of several factors such as plant growth regulators and carbon source on cell growth, and determine their oleanolic acid content. METHODS: Cell culture was established by using 2 g fresh weight of 30 day old friable callus derived from in vitro stem segment in 50 mL of liquid medium with a shaking speed of 220 rpm. The culture was then incubated at 25±2ºC with a shaking speed of 120 rpm in the period of 12 h daylight at a light intensity of about 6.75 µmol/m2/s. Cell growth was measured by fresh and dry biomass at 16 h day. Oleanolic acid content was determined using HPLC analysis. RESULTS & DISCUSSION: The study results showed that MS medium containing 2% sucrose as a carbon source, supplemented with 1 mg/L 6-benzylaminopurine and 0.5 mg/L 2,4-dichlorophenoxyacetic acid was the most appropriate growth medium. Cell biomass and oleanolic acid content reached the highest values of 0.43 g dry weight/flask and 25.4 mg/g dry weight, respectively. CONCLUSION: These results indicated the potential production of oleanolic acid, a compound with high pharmacological value, from P. fruticosa cell culture.

Chemical Compositions, Mosquito Larvicidal and Antimicrobial Activities of Essential Oils from Five Species of Cinnamomum Growing Wild in North Central Vietnam.

Members of the genus Cinnamomum (Lauraceae) have aromatic volatiles in their leaves and bark and some species are commercially important herbs and spices. In this work, the essential oils from five species of Cinnamomum (C. damhaensis, C. longipetiolatum, C. ovatum, C. polyadelphum and C. tonkinense) growing wild in north central Vietnam were obtained by hydrodistillation, analyzed by gas chromatography and screened for antimicrobial and mosquito larvicidal activity. The leaf essential oil of C. tonkinense, rich in ß-phellandrene (23.1%) and linalool (32.2%), showed excellent antimicrobial activity (MIC of 32 µg/mL against Enterococcus faecalis and Candida albicans) and larvicidal activity (24 h LC50 of 17.4 µg/mL on Aedes aegypti and 14.1 µg/mL against Culex quinquefasciatus). Cinnamomum polyadelphum leaf essential oil also showed notable antimicrobial activity against Gram-positive bacteria and mosquito larvicidal activity, attributable to relatively high concentrations of neral (11.7%) and geranial (16.6%). Thus, members of the genus Cinnamomum from Vietnam have shown promise as antimicrobial agents and as potential vector control agents for mosquitoes.