Ressources alimentaires non conventionnelles

Unconventional Food Resources. Concepts of ethnobotany, ethnozoology and ethnoecology are defined and their respective development recounted. The geographic frame is afterwards specified: Tropical Africa. Diversity of wild edible vegetable products is illustrated by some examples: cyanobacteria from Chad, mushroom consumption in the Zambezian region and pteridophagy. Upper plants are approached according to six ensembles, namely starchy fruits and seeds, oilseeds and nuts, fleshy fruits, reserve organs, flowers and vegetable species. After recalling the diversity of insects eating at world scale, four orders are briefly presented: coleoptera, isoptera (termites), lepidoptera (mainly caterpillars or campeophagy) and orthoptera. Finally the nutritional input of unconventional foods is underlined as well as the urgent need of their further studies

Reduced glutamate decarboxylase activity in rat islet β cells which survived streptozotocin-induced cytotoxicity

AbstractRat pancreatic β cells exhibit a 16-fold higher glutamate decarboxylase (GAD) activity than islet non-β cells, but a similar glutamate dehydrogenase (GDH) activity, β Cells which survive exposure to 2 mM streptozotocin only contain 10 percent of the GAD activity of control cells, but their GDH activity remains unaltered. Culture of streptozotocin-treated β cell preparations with 2 mM nicotinamide reduces the number of dead cells and prevents in part the decline in GAD activity of surviving β cells. These data indicate that loss in activity of the β cell specific enzyme GAD can serve as marker for β cells which survived a destructive process. It is furthermore demonstrated that nicotinamide increases the percent surviving cells and decreases their loss in GAD activity

Early stages of natural revegetation of metalliferous mine workings in South Central Africa: a preliminary survey

The various types of mining sites resulting from human activities in the Katangan Copper Bow and the Zambian Copperbelt are described and a typology is presented whereby ten different situations are recognized. Performance as well as distribution of the diverse plant species observed on these sites is considered. A set of nine ecological conditions is suggested, based both upon the heavy metal content of soil as well as its state of hydration. One taxon is identified as an indicator of each condition recognized. The information presented here is a preliminary requirement for planning the revegetation of metalliferous sites within the area

Structure diversity in three forest types of north-eastern Thailand (Sakaerat Reserve, Pak Tong Chai)

The aim of the present study is to provide a basic knowledge in view of a better understanding of the global structure of threetropical forests at the Sakaerat Environmental Research Station (Pak Tong Chai district, Northeastern Thailand): a drydipterocarp forest (DDF), a dry evergreen forest (DEF) and an intermediate stage (DDFwf), characterized by the absence offire since 29 years in a pyro-climax. These forest ecosystems were contrasted by the composition and floristic structure, thebasal area and the tree density. The species richness increases with the passage from the DDF, the most open environment, to the DDFwf, the most densely wooded. By these tree density and basal area, the DDF (602 trees/ha at DBH ³ 5 cm, 14.2 m2/ha) and the DEF (992 trees/ha at DBH ³ 5 cm, 29.0 m2/ha) studied belong to the typical tropical ecosytems of southeast Asia. The man-made fires and anarchic forest exploitations are a danger for the stability of these different ecosystems

Ophioglossum polyphyllum A. Braun in Seub. (Ophioglossaceae, Pteridophyta), a rare potherb in south central Tibet (T.A.R., P.R.China)

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