Nutrient composition and nutritional importance of green leaves and wild food resources in an agricultural district, Koutiala, in southern Mali.

This paper discusses the nutrient composition and the nutritional importance of green leaves and wild gathered foods in an area with surplus food production in Mali. In this West African country, there is little information about the nutrient composition and the nutritional quality of foods in general, and of wild gathered foods in particular. Food frequency was collected in two cross-sectional surveys. Focus group discussions with women in the area were used to collect information about seasonality, availability and preparation of various foods. Selected food samples were collected for chemical analysis of nutrient composition. The food samples of green leaves (Adansonia digitata, Amaranthus viridis, Tamarindus indica, Allium cepa), seeds and flour (Parkia biglobosa) and fruits (Tamarindus indica) were analysed for water, energy, fat, protein, minerals, amino acids and carotenoids. Availability and use of the foods varied with seasons. In the rainy season, wild gathered foods (e.g. A. digitata) were used as much as fresh cultivated foods (e.g., A. viridis and A. cepa). The wild food resources were more frequently used in rural than in urban areas, with A. digitata as the dominating green leaves. Green leaves were rich in energy, protein and minerals (calcium, iron). Leaves of A. viridis were, in particular, rich in beta-carotene (3290 micrograms/100 g). Chemical score in dried green leaves varied from 47 (A. cepa) to 81 (A. digitata), with lysine as the first limiting amino acid. P. biglobosa fermented seeds, with 35% fat and 37% protein were a complementary source of lysine in the diet. Based on the seasonality, the frequency of use and the nutrient contents of selected green leaves and wild gathered foods in Koutiala district, it is concluded that these traditional and locally produced foods are valuable and important nutrient contributors in the diet both in rural and urban areas, but most important in rural areas.

Metabolic effects on growth and muscle of soya-bean protein feeding in cod (Gadus morhua).

The aim of the present study was to investigate the effect of soya-bean protein on growth and muscle metabolism in fish. Cod, Gadus morhua, were fed on a fish-feed formula with the high-quality fish-meal protein being replaced by 100, 200 or 300 g soya-bean protein/kg fish-meal protein. The feeding experiment lasted for 43 d at a water temperature of 7-8 degrees and a sea water salinity of 3.5%. At the 200 g/kg level of soya-bean protein, food intake and growth rate were similar to those of the controls. At the 300 g/kg level of soya-bean protein, food intake was diminished by 6% and growth by 67% relative to control levels. In muscle, sarcoplasmic protein (/g wet weight) was significantly decreased by 14%. Myofibrillar protein (/g wet weight) was unchanged. Levels of RNA in the myofibrillar fraction decreased at all three levels of soya-bean protein, and that of the sarcoplasmic fraction decreased at the highest level of legume-protein. With increased levels of soya-bean protein, RNA:DNA declined by 18% from 1.88 to 1.54. The contractile protein myosin heavy chain (/mg protein and /g wet weight) and myosin heavy chain-specific mRNA (/mg RNA) were not significantly affected by dietary conditions. Expressed per g wet weight, the decline by 21% of the specific mRNA depended on the total RNA content which decreased with the increase in soya-bean protein. Acid proteinase activity was lowest at the 200 g/kg level, showing a decrease of 23%.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary protein levels affect growth and protein metabolism in trunk muscle of cod, Gadus morhua.

Cod (Gadus morhua) of 50 g body weight were kept at 14 degrees C. The fish were fed ad libitum during 80 days a diet containing protein levels which in terms of total energy corresponded to 25%, 45% or 65%. Growth increased in accordance with protein-energy levels. The protein content per gram of wet weight of white trunk muscle was unchanged, as was the myofibrillar protein myosin heavy chain determined by the antigen-antibody reaction of the enzyme-linked immunosorbent assay. The amount of messenger ribonucleic acid (mRNA) coding for myosin heavy chain was lower at 25% than at 45% or 65% protein-energy intake, the differences being significant per gram of wet weight of muscle. Acid proteinase activity was highest at the lowest protein-energy intake. Glycogen content in muscle increased with the protein-energy levels. It is concluded that the metabolic response of white trunk muscle to graded protein-energy intake included a change in the capacity to synthesize myosin heavy chain as judged by its mRNA content. The protein content per gram of wet weight was unaffected by dietary protein-energy levels of 25%, 45% and 65%, but protein accretion and thus growth of the animals increased with the protein intake. Dietary protein-energy restriction caused a rise in acid proteinase activity and a decrease in content of mRNA for myosin heavy chain, resulting in a diminished growth rate at an unchanged protein content per gram of wet weight of muscle.

Myosin heavy chain synthesis in white trunk muscle of cod (Gadus morhua) fed different ration sizes.

In this study the expression of myosin heavy chain was investigated at the messenger RNA and protein level of the muscle ribosome. Cod (Gadus morhua) weighing 80 g were fed for 70 days eitherad libitum or with rations consisting of 75%, 50%, or 25% of thead libitum food intake. Protein and RNA contents of the ribosome from the white trunk muscle decreased with the diminished ration sizes. Myosin heavy chain content relative to total ribosome protein increased with the 50% ration size but fell again to thead libitum level at 25%. Expressed relative to RNA, a decrease in the protein content occurred in parallel with the decreasing ration size. The amount of protein/total muscle homogenate fell with diminished ration sizes, and that of myosin heavy chain/mg of protein remained unchanged with a slight increase at the 25% food energy intake. The messenger RNA for myosin heavy chain (relative to poly(A)(+) messenger (RNA) was increased in response to the decreased ration size but was decreased when calculated per g wet weight of the muscle. The changes in messenger RNA for myosin heavy chain were less pronounced than those of the protein itself. The levels of gene transcription and translation for myosin heavy chain were affected to a lesser extent by the low food intake than the synthesis of total RNA and protein. Immunological methods and messenger RNA hybridization to cloned DNA for myosin heavy chain permitted the precise determinations of the events taking place during a food-energy supply shortage. Translation appeared to diminish prior to changes in messenger RNA concentrations.

Purification of fish muscle myosin heavy chain and quantification of the specific polyribosome-bound polypeptide.

A purification procedure for fish myosin heavy chain is described. The protein was injected into rabbits for production of antibodies. The specificity of the antibodies was determined by immunoblotting. The enzyme-linked immunosorbent assay technique was applied to quantify myosin heavy chain bound to isolated polyribosomes of epaxial muscle from fish.

The influence of the ratio of protein energy to total energy in the feed on the activity of protein synthesis in vitro, the level of ribosomal RNA and the RNA-DNA ratio in white trunk muscle of Atlantic cod (Gadus morhua).

Cod (Gadus morhua) were fed diets containing protein energy to total energy levels (PE/TE) of 10.0, 20.6, 29.6, 38.4, 56.2 and 74.1% for 21 days. Ribosomes were isolated from the white trunk muscle tissue, the capacity for protein synthesis in vitro determined and related to muscle tissue wet weight rRNA and DNA. Protein concentrations of less than 47.4% PE/TE in the diets reduce the ribosomal capacity for protein synthesis per g wet weight and per mg DNA, and the tissue contents of rRNA and ratio of rRNA/DNA. The capacity for muscle protein synthesis in vitro is a significant and sensitive parameter of protein inadequacy in fish diets.

Properties of white trunk muscle from saithe Pollachius virens, rainbow trout Salmo gairdneri and herring Clupea harengus: protein synthesis in vitro, electrophoretic study of proteins.

1. Ribosomes were isolated from white trunk muscle of saithe (Pollachius virens), rainbow trout (Salmo gairdneri) and herring (Clupea harengus). 2. Incorporation of amino acids into protein by the ribosomes was determined in systems containing liver cell sap from rainbow trout. 3. Incorporation of phenylalanine into protein was as follows: saithe 163.19 +/- 7.64 pmol, rainbow trout 126.99 +/- 3.07 pmol, herring 29.34 +/- 1.28 pmol per g wet weight of tissue and 4 min of incubation at 28 degrees C. 4. Proteins associated with the ribosome fractions showed minor differences between the species as analysed by polyacrylamide gel electrophoresis in sodium dodecylsulfate. Proteins of myofibrillar origin were predominant in those fractions.

Protein synthesis in vitro by epaxial muscle polyribosomes from cod, gadus morhua.

1. Ribosomes were isolated from epaxial muscle of cod (Godus morhua). 2. Incorporation of amino acids into protein was determined in systems containing liver cell sap from rat or rainbow trout (Salmo gairdneri R.). Maximal rates were at 35 degrees and 28 degrees C, respectively. The optimum pH was between 7.5 and 8.0. 3. Ribosomes isolated from muscle stored at -80 degrees C between 1 and 14 days retained 86% of the activity of ribosomes from fresh tissue. 4. Starvation of fish for 10 days reduced amino acid incorporating activity of isolated ribosomes to 15-20%. 5. All ribosome preparations used in the experiments were analysed by sucrose density gradient centrifugations.

[A bacteriological investigation of Norwegian cod liver oil (author's transl)]. / En bakteriologisk undersøkelse av norsk medisintran

Samples of medicinal cod liver oil collected from four of the main producers in Norway have been investigated for content of microorganism. Viable counts for bacteria and fungi were found to be low. No coliform bacteria, coagulase positive Staphylococcus or Pseudomonas could be detected. The findings suggest that the main part of the flora found in cod liver oil belongs to the family Micrococcaceae. Several of the isolated colonies showed lipolytic activity.

Determination of total choline in biological materials.

A microbiological eight-point parallel line assay for the determination of choline has been developed, using Neurospora crassa cholineless-1 as test organism. In the common procedure the mold is grown at 25 degrees C in 25 ml basal medium at pH 5.9-6.0. Growth studies showed, however, that a better log dose-response curve, with respect to the linear part of the curve, was obtained when the organism was grown at 30 degrees C, in 20 ml experimental volume and at pH 5.5. The proprosed eight-point assay was tested by comparison with the common procedure. Although repeated analyses of a test solution showed no significant difference in the mean values obtained, a greater scatter of the single values about the mean was observed when analyzing according to the common procedure. The developed procedure was also applied to different samples of biological material. The analysis of variance proved the parallelity and linearity of the dose-response curves. As a result of the variation between the replicates could be used as the experimental error of the assay when the confidence limits of the samples were computed.