An oral carcinogenicity and toxicity study of senna (Tinnevelly senna fruits) in the rat.

Senna (Tinnevelly senna fruits), a known laxative derived from plants, was administered by gavage to Sprague-Dawley (Crl:CD (SD) BR) rats once daily at dose levels of 0, 25, 100 and 300 mg/kg/day for up to 104 consecutive weeks. Based upon clinical signs related to the laxation effect of senna, the highest dose (300 mg/kg/day) was considered to be a maximum tolerated dose. Sixty animals per sex were assigned to the control and dose groups. Assessments included clinical chemistry, hematology, full histology (control and high-dose groups; in addition, low and mid dose: intestinal tract, adrenals, liver, kidneys, brain and gross lesions) and toxicokinetics. The primary treatment-related clinical observation was mucoid feces seen at 300 mg/kg/day. When compared to controls, animals administered 300 mg/kg/day had slightly reduced body weights, increased water consumption and notable changes in electrolytes in serum (increases in potassium and chloride) and urine (decreases in sodium, potassium and chloride). The changes in electrolytes are most likely physiologic adaptations to the laxative effect of senna. At necropsy, dark discoloration of the kidneys was observed in animals in all treated groups. Histological changes were seen in the kidneys of animals from all treated groups and included slight to moderate tubular basophilia and tubular pigment deposits. In addition, for all treated groups, minimal to slight hyperplasia was evident in the colon and cecum. These histological changes, together with the changes seen in the evaluation of clinical chemistry and urine parameters, have been shown to be reversible in a previous 13-week rat study of senna. No treatment-related neoplastic changes were observed in any of the examined organs. Based upon these data, it is concluded that senna is not carcinogenic even after daily administration for 2 years at dosages of up to 300 mg/kg/day in Sprague-Dawley rats.

Cultivation of medicinal plants in alley cropping systems with Moringa oleifera in the Virgin Islands

Medicinal and aromatic plants (MAPs) are horticultural crops with socio-economic significance in the Caribbean. People of the Caribbean maintain the tradition of making 'bush (herb) teas' as part of their daily activity. 'Bush tea' is made with a variety of herbs that are combined for their culinary and medicinal properties. Cultivating these plants complements conventional fruit and vegetable production in the Virgin Islands and enhance small-farm productivity. This study was initiated to evaluate the agronomic and economic potential of agroforestry systems involving MAPs with focus on alley cropping. Field experiments were conducted to determine yield and productivity of popular species of medicinal plants and aromatic herbs commonly used in the Virgin Islands. Medicinal plants included 'inflammation bush' (Verbesina alata), 'worrywine' (Stachytarpheta jamaicensis) and 'japana' (Eupatorium triplinerve) ... Data were collected on fresh and dry matter yield ... Results indicated yield of intercropped medicinal plants and herbs were not significantly reduced during the first harvest, but yield tended to decrease in subsequent harvest suggesting that tree-crop competition was minimal during the early establishment stage

Inhibitory effect of topical application of a green tea polyphenol fraction on tumor initiation and promotion in mouse skin.

A green tea polyphenol fraction was evaluated for its ability to inhibit tumor initiation by polycyclic aromatic hydrocarbons and tumor promotion by a phorbol ester in the skin of CD-1 mice. Topical application of the green tea polyphenol fraction inhibited benzo[a]pyrene- and 7,12-dimethylbenz[a]-anthracene-induced tumor initiation as well as 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced tumor promotion. Topical application of the green tea polyphenol fraction also inhibited TPA-induced inflammation, ornithine decarboxylase activity, hyperplasia and hydrogen peroxide formation. Studies with individual polyphenolic compounds in green tea indicated that topical application of (-)-epigallocatechin gallate, (-)-epigallocatechin and (-)-epicatechin gallate inhibited TPA-induced inflammation in mouse epidermis.

Cultivation of medicinal plants in alley cropping systems with Moringa oleifera in the Virgin Islands

Medicinal and aromatic plants (MAPs) are horticultural crops with socio-economic significance in the Caribbean. People of the Caribbean maintain the tradition of making 'bush (herb) teas' as part of their daily activity. 'Bush tea' is made with a variety of herbs that are combined for their culinary and medicinal properties. Cultivating these plants complements conventional fruit and vegetable production in the Virgin Islands and enhance small-farm productivity. This study was initiated to evaluate the agronomic and economic potential of agroforestry systems involving MAPs with focus on alley cropping. Field experiments were conducted to determine yield and productivity of popular species of medicinal plants and aromatic herbs commonly used in the Virgin Islands. Medicinal plants included 'inflammation bush' (Verbesina alata), 'worrywine' (Stachytarpheta jamaicensis) and 'japana' (Eupatorium triplinerve) ... Data were collected on fresh and dry matter yield ... Results indicated yield of intercropped medicinal plants and herbs were not significantly reduced during the first harvest, but yield tended to decrease in subsequent harvest suggesting that tree-crop competition was minimal during the early establishment stage (AU)