Semi-synthesis of nitrogen derivatives of oleanolic acid and effect on breast carcinoma MCF-7 cells.

BACKGROUND: Oleanolic acid is a triterpenoid that has shown in vitro cytotoxic activity against human tumour cells and is known to be present in many higher plants. MATERIALS AND METHODS: Oleanolic acid is known to have some biological potential including anticancer property. Oleanolic acid was isolated from the ethyl acetate fraction of Syzygium aromaticum seed with an aim of dervitatising the functional group and evaluating the biological activities of the semi-synthesised compounds. Acylation of the alcohol functional group of the oleanolic acid afforded the opportunity of hydrazine reaction to give 3-acetoleanolic hydrazide. Further reaction of 3-acetoleanolic hydrazide with benzyladehyde, glacial acetic acid and methanol resulted in the synthesis of the corresponding 3-acetoxyoleanolic hydrazone. RESULTS: The semi-synthetic oleanolic acid derivatives did not exhibit enhanced cytotoxic activity over oleanolic acid itself. CONCLUSION: 3-acetoxyoleanolic hydrazide has a potent anticancer activity.

Internalized racism is associated with elevated fasting glucose in a sample of adult women but not men in Zimbabwe.

OBJECTIVES: Internalized racism (INR) is associated with metabolic abnormalities among African Caribbean women. The current study was conducted to determine if similar associations exist among Black women living in Africa. METHODS: In 2003, a stratified random sample of Black adults ages > or =18 years was drawn from four high-density suburbs of the city of Bulawayo, Zimbabwe. A total of 318 persons (90% of those recruited) participated. Face-to-face interviews were used to gather information on demographic variables, health history, internalized racism, anthropometric measurements and blood pressure. Internalized racism, the extent to which individuals agree with racist stereotypes about their race, was measured with a standardized questionnaire. A fasting blood sugar level was also measured for each participant. Persons with diagnosed diabetes or incomplete data (n=44) were excluded from analyses. RESULTS: Women (n=188) and men (n=86) did not differ significantly by age, INR score, waist circumference or fasting glucose level. The mean body mass index of women (23.6 kg/m2) was higher (P<.05) than that of men (22.3 kg/m2). INR was significantly correlated with waist circumference, diastolic blood pressure and fasting glucose among women but not among men. In multiple logistic regression analyses using the data for women, a high INR remained independently associated with abnormal fasting glucose (odds ratio=2.74, P=.0085) after adjusting for potential confounders including adiposity. CONCLUSIONS: These findings show the consistency of the association of high INR with metabolic abnormalities among Black women in the Diaspora.

Composition and bioactivity of the leaf essential oil of Heteropyxis dehniae from Zimbabwe.

The leaf oil of Heteropyxis dehniae Suess. (Heteropyxidaceae) was obtained by hydrodistillation and analyzed by GC/MS. The most abundant essential oil components are linalool (58.3%), 4-terpineol (9.8%), alpha-terpineol (3.6%), and caryophyllene oxide (3.1%). The antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and Aspergillus niger, and the in vitro cytotoxicity of the oil on PC-3, MDA-MB-231, Hs 578T, MCF7, SK-MEL-28, and 5637 human tumor cells were also examined. Caryophyllene oxide shows notable cytotoxic activity with LC50 values of 147-351 microM.

Cytotoxic activity of Ozoroa insignis from Zimbabwe.

The crude methanol bark extract of the Zimbabwean medicinal plant, Ozoroa insignis, showed in-vitro cytotoxic activity against Hep-G2 (human hepatocellular carcinoma), MDA-MB-231 (human mammary adenocarcinoma), and 5637 (human primary bladder carcinoma). Bioactivity-directed chromatographic separation led to isolation of anacardic acid and ginkgoic acid as the cytotoxic components.