PubMed HealthSearch

SEARCH · PubMed Health

Results for “Manihot”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

35 records · Page 2Linked to original sources

RNA and protein components of maize streak and cassava latent viruses.

Polyacrylamide gel electrophoresis indicated that maize streak (MSV) and cassava latent (CLV) viruses each contain one species of protein and two of RNA. The estimated protein mol. wt is 28000 for MSV and 34000 for CLV. The mol. wts obtained for the two RNA species using formamide-containing gels were the same for the two viruses: 1-7 X 10(6) and 1-3 X 10(6). It is suggested that the viruses have a two-part genome and that the tendency of their nucleoprotein particles to form pairs favours the delivery of complete genomes to sites of infection.

Genotype

High-temperature production of protein-enriched feed from cassava by fungi.

A simple, nonaseptic, low-cast process for the conversion of cassava, a starchy tropical root crop, into microbial protein for use as animal feed was sought. Screening tests culminated in the isolation of a thermotolerant, amylase-producing mold, designated I-21, which was identified as Aspergillus fumigatus. The optimum pH for protein synthesis was 3-5, but the optimum temperature was less than the desired temperature (larger than or equal to 45 C) required for a nonaseptic fermentation. A. fumigatus I-21 and its asporogenous mutant I-21A grew equally well in a medium prepared from whole cassava roots with a mean protein doubling time at 45 C and pH 3.5 of 3.5 h. In batch culture, approximately 4% carbohydrate, supplied as whole cassava, could be feremented in 20 h, giving a final yield of 24 g of dry product, containing 36.9% crude protein, per liter. The conversion of carbohydrate used to crude protein was 22.1%. When determined as amino acids, the protein content of the product, which contained cassava bark and other unfermented residues, was 27.1%. With urea as the nitrogen source, no pH control was necessary. Preliminary data indicated that medium prepared from whole cassava roots was inhibitory to the mold unless the cassava pulp was heated to 70 C immediately after being ground. Heating to 70 C was required to gelatinize the starch and permit its complete utilization.

Animal Feed

Fate of orally dosed linamarin in the rat.

Wistar rats, about 100 g in weight, were dosed by stomach tube with 30 mg of pure linamarin. No intact linamarin was identified in the feces or blood but 5.65 mg was excreted in the urine along with 0.823 mg of thiocyanate ion. A 50-mg dose of linamarin was lethal to 7 of 10 rats receiving this dose.

Administration, Oral

Effects of cyanogenic agents on reproduction and neonatal development in rats.

A diet consisting of 50% gari (a form of cassava meal) was found to cause no significant biochemical and haematological changes in adult female rats. Although this diet caused a significant increase in their serum thiocyanate levels, there was no corresponding significant increase in the weight of their thyroid glands. The offspring of these rats had significantly lower birth weights and brain weights and never attained the same adult weights as those of the controls. Adult female rats fed a diet consisting entirely of raw cassava had significantly reduced haematological and biochemical indices. This diet also caused an increased incidence of cannibalism and a significant reduction in the frequency of pregnancy, the average number of the litter and the birth weights among these rats. In addition there was an increased incidence of neonatal deaths among the offspring which also had poor development, reduced brain weights and an increased tendency towards biting their litter-mates. Adult female rats fed diets containing 5 and 10 g cyanide/100 g laboratory diet survived for more than 3 months but never became pregnant. They developed enlarged thyroid glands and tumours of the large intestine. The relevance of these findings to the areas of the world where cyanogenic glycosides form the staple diet is discussed.

Animals

Dietary cyanide and tropical malnutrition diabetes.

Two categories of diabetes are recognized in the temperate zone--ketosis-prone diabetes requiring insulin and diabetes not requiring insulin. Another unique type of diabetes occurs in the tropics. It has two forms, both different from either form of temperate zone diabetes. Type J and pancreatic diabetes are both characterized by youth onset, antecedent malnutrition, substantial insulin requirement, and resistance to ketosis. In the tropical countries where they are found, both forms are associated with specific dietary practices, including a nutritionally marginal protein intake. The close association with low protein intake distinguishes this form of diabetes from that occurring in North America, Europe, and Oceania. The geographic distribution of malnutrition diabetes, in addition to being limited to the tropics, coincides regularly with the consumption of tapioca (cassava) or other foods that contain cyanide-yielding substances. Ingested cyanide is normally detoxified, principally, by conversion to thiocyanate. This detoxification requires sulfur, derived principally from amino acid sources. Studies in the rat indicate a remarkable ability to detoxify ingested cyanide, a reduction in urinary thiocyanate excretion when protein intake is lowered (especially during growth), production of marked hyperglycemia by either oral or parenteral cyanide, and the development of cyanosis and epidermal changes when there is prolonged exposure to cyanide. Both the association of malnutrition diabetes with food cyanogens and our laboratory observations support a role for cyanide in its pathogenesis.

Adolescent

The tropical amblyopia syndrome (or tropical nutritional amblyopia) in the Mid-Western State of Nigeria.

One hundred and seven patients from the Mid-Western State of Nigeria with the tropical amblyopia syndrome are reported. Ninety-five patients (88.8%) had the amblyopia syndrome mainly; twelve patients (11.2%) had amblyopia and other manifestations of the tropical ataxic neuropathy. The young, aged 10-20 years, represented by sixty-six patients (61.8%), are predominantly affected by the uncomplicated syndrome. Thirteen patients (12.1%) showed muco-cutaneous evidence of avitaminosis. Fifty patients (46.7%) had temporal pallor of the optic discs, bilaterally, another fifty (46.7%) had normal discs, two (2.8%) showed pink discs. Generalized field constriction is the common field defect, though central or centro-caecal scotoma can occur. Red/green defect was present in seven patients. It is a disease of the poor or those living on a basic monotonous diet consisting mainly of cassava (mannihot) and its derivatives. It is a significant cause of defective vision in Mid-Western Nigeria.

Adolescent

Safety evaluation of Aspergillus fumigatus grown on cassava for use as an animal feed.

A safety evaluation of Aspergillus fumigatus I21, grown in a cassava carbohydrate and salts medium, was undertaken. Male weanling rats were fed the fungus at 20, 30 and 40% of the diet for 90 days. A control group was given soybean oil meal as the sole source of protein. Weekly determinations of the body weights and feed consumptions were made. A few days prior to termination of the feeding study, a kidney function test was undertaken on the rats. At the end of the feeding period hematology, blood biochemistry, urine analyses and histopathology studies of various tissues were carried out, and organs were weighed. Rats fed A. fumigatus I21 gained less weight than the controls, but kidney weights were increased. Increases in serum alkaline phosphatase and glutamic-oxaloacetic transaminase were not related to dose level. The blood urea nitrogen was increased for the rats fed 40% of the fungus. Rats fed 30 and 40% of the fungus I21 showed a significant drop in albumin. Deficiency in methionine or other essential amino acids through a limited feed consumption may have caused a decrease in albumin synthesis. Rats fed the highest level of the fungus showed increases in neutrophils and monocytes concomitant with decreases in lymphocytes and eosinophils which may be a response to stress. The urine analyses did not reveal any significant differences. The test rats were capable of concentrating urine adequately when deprived of water for 24 hours. No significant differences between the control and experimental groups were found by histopathological examinations.

Animal Feed

[Pathogenesis of endemic goiter: evidence of a dietary factor different from iodine deficiency (author's transl)].

The role of cassava was investigated in particularly severe endemic goiter area (Ubangi). Dietary intake of cassava induces an increase of plasma thiocyanate concentration and an increase of urinary excretion of stable iodine. Generalized iodine deficiency induces very high thyroid uptakes; the other parameters of thyroid function are more or less affected according to the dietary intake of thiocyanate. When thiocyanate intake is high an adaptation is obtained only at the expense of a drop of plasma T4 level and very high increase of plasma TSH.

Democratic Republic of the Congo

[Nitrogen balance in adults and experimental study in rats fed with rice, beans and manioc flour supplemented with proteins].

Rice, beans and manioc flour are foods eaten daily in Northeast Brazil. Manioc flour is a source of energy, having a low protein content. There has been a great interest to supplement manioc flour with proteins. The present study was planned to show the nutritive value of a basic diet including rice, beans, manioc flour and other local foods, supplemented with different sources of proteins. The experiment was carried out in humans and rats. The supplements used were casein (Ca), isolated soy protein (PS) and a dry residue of a soymilk preparation (RSLS). Through nitrogen balance studies in adults it was shown that the diets with casein or isolated soy protein had a good absorption and retention of nitrogen. The addition of the soymilk residue resulted in a poor acceptance of the experimental diet; negative nitrogen retention was observed in the three persons who accepted the food and completed the balances studies. The same diets offered to humans, with the same protein supplements, were fed to rats. The nutritive value measured in the animals were similar, in all diets with all supplements, including the one with the dry residue of soymilk. The present results call the attention to the problems of transfering animal results to humans. It was also discussed the possibility of adding casein or isolated soy protein as an eventual protein supplement to manioc flour for human feeding.

Adolescent