Anticandidal activity of the volatile oil from the aphrodisiac Cameroonian spice Mondia whitei (Hook. F.) Skeels

M. whitei is widely distributed in moist to wet areas of tropical Africa and used in several countries by traditional healers since ancient time. Previously, some biological activities were recognized for methanolic extracts of M. whitei such as antibacterial, antifungal and antioxidant. The ethanolic extracts of M. whitei displayed cytoxic effects on breast cancer cell lines and less toxicity toward the non-tumor cell line. In this work we investigated the chemical composition, antimicrobial activity, antioxidant capacity and the effect on the growth of some human tumour cell lines of the essential oil form the plant roots. Dry roots were grounded and hydrodistilled in clevenger-type apparatus for 6 hours. Volatile components were separated by GC and analysed by MS. The major component was the MBE accounting for 79.6% of the oil, followed by benzyl isothiocyanate, BITC (12.4%). The antioxidant activity of from M. whitei essential oil was measured by using different radical scavenging methods such as DPPH, ABTS assay and ferric reducing antioxidant power (FRAP assay). There was antioxidant activity that could be mainly attributed to the presence of MBE. The cytotoxicity was tested on cancer cell lines using the MTT assay. Results indicated that the essential oil was toxic to all cancer cell lines. The IC50 ranged from 5.5 to 6.77 μg/mL (28.8 to 35.42 μM for MBE; 4.6 to 5.6 μM for BITC), values close to the IC50 of cisplatin, used as the positive control. Antimicrobial activity of the essential oil was assessed by disc diffusion and microdilution methods. The essential oil had a wide spectrum of activity. All the species, namely Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Candida albicans were inhibited. The present study provides additional data on the root bark essential oil of M. whitei that support the possible utilization and development of this as an antimicrobial and antioxidant agent. Equally important, the essential oil could be an alternative resource for preparing 2-hydroxy-4-methoxybenzaldehyde an important aroma and flavoring agent that could be used in production of soft drinks, beer and bakery products.