The Nigeria high glycemic index starchy foods, obesity, and the environment.

BACKGROUND: Glycemic index has generated a lot of debate for nearly 30 years, especially as it relates to the control for the treatment of diabetes. OBJECTIVES: This study determined the glycemic index (GI) of ten processed Nigerian foods and revealed their similarity in the release of glucose on consumption. METHODS: The food items tested were made from yam tubers, cassava tubers and local cereals. These foods were served to human volunteers in several processed forms which resulted in viscous pastes. RESULTS: The GI results are related to the increased incidence of overweight and obesity in the middle class Nigerians. CONCLUSION: It is suggested that these processed foods should be discouraged in the regular dietary plan if Nigerians desire to stay slim and save the planet by reducing carbon emission and climate change.

Effect of soaking, cooking and germination on the oligosaccharide content of selected Nigerian legume seeds.

The identity and quantity of and effect of processing on raffinose oligosaccharides in raw, mature seeds of lima beans (Phaseolus lunatus), pigeon peas (Cajanus cajan), African yam beans (Sphenostylis sternocarpa) and jackbeans (Canavalia ensiformis) were investigated. Sucrose, raffinose, stachyose and verbascose were identified by HPLC in all the legume seeds. The total alpha-galactoside contents of the seeds in decreasing order were African yam beans 3.84 mg/100 mg; white lima beans 3.62 mg/100 mg; cream pigeon peas 3.51 mg/100 mg; red lima beans 3.37 mg/100 mg; jackbeans 2.83 mg/100 mg and brown pigeon peas 2.34 mg/100 mg. The predominant oligosaccharide was verbascose in pigeon peas and stachyose in the other three legumes. Cooking unsoaked seeds brought about a greater reduction in the total alpha-galactoside content than soaking for nine hours. The removal of oligosaccharides was higher in legumes cooked in alkaline solution than in water. Germination quantitatively reduced raffinose, stachyose and verbascose while sucrose was increased in all seeds except red lima beans and jackbeans.

Differential effects of chronic cyanide intoxication on heart, lung and pancreatic tissues.

The histotoxic effects of chronic cyanide insult on heart, lung and pancreatic tissues, and some corroborative enzyme and metabolite changes were studied in New Zealand White rabbits using colorimetric, enzymatic and histochemical methods. Two groups of rabbits were fed for 10 months on either pure growers mash or grower mash +702 ppm inorganic cyanide. There were no significant differences in time-course profiles of serum amylase and fasting blood glucose between the cyanide-fed group and control. Pancreatic islet and heart histologies showed no pathological changes, and there were no significant differences in both serum and heart aspartate transaminase activities between the two groups. However, there were significant decreases (P<0.01) in alkaline phosphatase activity in the lungs of the cyanide-fed group, with corresponding significant (P<0.05) increases in the serum activity of the enzyme. Histological examination of lung tissue of the cyanide-treated rabbits revealed focal areas of pulmonary oedema and necrosis. These results suggest the existence of variabilities in tissue susceptibilities to the toxic effect of chronic cyanide exposure. It would appear that chronic cyanide exposure may not predispose to diabetes in the presence of adequate protein intake.

Liver and kidney lesions and associated enzyme changes induced in rabbits by chronic cyanide exposure.

The effect of prolonged chronic cyanide exposure on liver and kidney integrity, as well as some associated enzyme and metabolite changes, were investigated in New Zealand white rabbits (initial mean weight 1.52 kg) using a combination of colorimetric, spectrophotometric, enzymatic, gravimetric and histological procedures. Two groups of rabbits were fed for 40 weeks on either pure growers' mash or growers' mash containing 702 ppm inorganic cyanide. Results obtained indicate that the cyanide-fed rabbits had significantly decreased liver activities of alkaline phosphatase, glutamate pyruvate transaminase and sorbitol dehydrogenase relative to controls (P<0.05). On the other hand, there were significant increases (P<0.05) in the serum activities of these enzymes in the cyanide-treated group. Kidney alkaline phosphatase activity was significantly decreased (P<0.05), while serum urea and creatinine were significantly higher (P<0.05) in the cyanide group relative to controls. The cyanide treatment led to significant increases in both tissue and serum activities of lactate dehydrogenase. In addition, liver and kidney rhodanese activities were significantly raised in the cyanide-fed group. There were marked degenerative changes in the liver and kidney sections from the cyanide-treated rabbits. These results suggest that chronic cyanide exposure may be deleterious to liver and kidney functions.

Anti-nutritional constituents of six underutilized legumes grown in Nigeria.

Six underutilized legume seeds grown in Nigeria namely, red and white lima beans, brown and cream pigeon pea, African yam bean and jackbean were analysed for different anti-nutritional factors Sojasapogenol B was identified as the predominant sapogenol in lima beans and jackbeans by capillary gas chromatography. The content of total inositol phosphates and individual inositol phosphates (IP6, IP5, IP4 and IP3) were analysed by ion-pair HPLC, being in the range of other legumes. Trace quantities of lupanine were identified as the alkaloid in jackbean. alpha-Galactosides were present in all the legume seeds, stachyose being the predominant galactoside in lima beans, African yam bean and jackbean, and verbascose in pigeon pea. The haemagglutinating activity was estimated as a measure of the lectin content of the samples. African yam bean was found to have the highest heamagglutinating activity. Tannins were found to be in low quantities. The presence of these anti-nutrients in relation to the nutritional value of the legume is discussed.