Recent advances in caffeine and theobromine toxicities: a review

Caffeine and theobromine are purine alkaloids widely consumed as stimulants and snacks in coffee and cocoa based foods and most often as part of ingredients in drugs. Man has enjoyed a long history of consumption of caffeine and theobromine. Recent interest in these two alkoloids, however, is centered on their potential reproductive toxicities. Caffeine and theobromine are now known to cross the placental and blood brain barrier thus potentially inducing fetal malformation by affecting the expression of genes vital in development. The developing fetus may not have developed enzymes for detoxification of these methylxanthine alkaloids via demethylation. There is a need, therefore, to protect the conceptus against insults from teratogens of this nature. Apart from its reproductive toxicity, the presence of caffeine and theobromine in cocoa could limit its potentials as a nourishing food. This is an issue that needs to be addressed by nutritionists and the food industry at large. This paper discusses the natural sources, consumption and uses, toxicity and the major advances in the reproductive toxicology of caffeine and theobromine. The biosynthesis of these compounds in plants, metabolism in mammalian systems and the involvement of cytochrome P450 are reviewed and summarized. Evidence in favor of the toxicity of these compounds in experimental animals is presented with emphasis on the implications of these findings in humans. The paper concludes with a call for caution in the use of caffeine and theobromine pending further and more elaborate investigations.     

Chemical composition of the edible leaves ofPterocarpus mildbraedii

Proximate composition, mineral element content, amino acid profile and the levels of some antinutrients in the edible leaves ofPterocarpus mildbraedii were determined. Moisture content was assayed as 85.12 percent (wet weight). Protein, fat, ash and fibre contents of the leaf (percent dry weight) were 25.84, 5.23, 6.44 and 7.56 respectively. Mineral element analysis showed high levels of calcium, potassium, magnesium, iron, copper, manganese and zinc. However, the level of sodium in the vegetable was low. Amino acid profile indicated that the leaf is rich in essential amino acids. The antinutrient levels of hydrogen cyanide and oxalate were low. The paper suggests the need to meet nutrient requirements through an increased use of this cheap but less popular food item with good nutritive potential.