Excised bean (Phaseolus vulgaris) leaves were used to measure changes in proline content and proline metabolism during rehydration in the dark after the leaves had been incubated in the dark 24 hours in a wilted condition.The increase in nonprotein proline which occurs in wilted leaves stopped immediately upon rehydration, and thereafter levels of proline declined. The rate of decline and the f...

Peters and his associates (1) demonstrated that there is a reduced oxygen consumption of the brain of polyneuritic pigeons. Addition of minute amounts of crystalline vitamin B1 in vitro to the avitaminous brain tissue restores the diminished tissue respiration. O’Brien and Peters (2) observed that the brains of vitamin B1-deficient rats and pigeons alike produced pyruvate in vitro and that the ...

Alcohol (ethanol; EtOH) provides fuel energy to the body (29.7 kJ (7. 1 kcal)/g, 23.4 kJ (5.6 kcal)/ml), as do other macronutrients, but no associated essential nutrients. The thermogenic effect of EtOH (on average 15 % of its metabolizable value) is much greater than that of the main substrates utilized by the body, i.e. fat and carbohydrates (CHO), suggesting a lower net efficiency of energy ...

We postulated that glycogen is a significant energy substrate compared with fatty acids and glucose in response to adrenergic stimulation of working rat hearts. Oxidation rates were determined at 1-min intervals by release of3H2O from [9,10-3H]oleate (0.4 mM, 1% albumin) and14CO2from exogenous [U-14C]glucose (5 mM) or, by a pulse-chase method, from [14C]glycogen. We estimated the 14C enrichment...

Lipids are an important fuel for submaximal aerobic exercise. The ways in which lipid oxidation is regulated during locomotion is an area of active investigation. Indeed, the integration between cellular regulation of lipid metabolism and whole-body exercise performance is a fascinating but often overlooked research area. Additionally, the interaction between environmental stress, exercise, and...

The proposed impact of slowly digestible sources of dietary carbohydrate in reducing the risk of developing obesity and related metabolic disorders remains unclear. The aim of the present study was to compare the postprandial metabolic response to the ingestion of glucose v. trehalose. We hypothesised that the reduced digestion and absorption rate of trehalose is accompanied by an attenuated gl...

The oxidation of fatty acids, carbohydrates and amino acids can be measured by quantifying the rate of excretion of labelled CO2 following administration of 14C- or 13C-labelled substrates at whole-body and tissue level. However, there is a theoretical need to correct the oxidation rates for the proportion of labelled CO2 that is produced via oxidation but not excreted. Furthermore, depending o...

Pre-exercise meals containing carbohydrates (CHO) are recommended to athletes, although there is evidence to suggest that a high fat meal prior to exercise increases utilisation of fats yet may not adversely affect performance. This study investigated the effect of a high fat and high CHO pre-exercise meal prior to high intensity intermittent exercise. Ten male recreational soccer players perfo...

Lignocelluloses are imperative structural components of plant cell wall and are profusely found in agricultural crop residues. The structural heterogeneity and recalcitrance of lignin limit the accessibility of cell wall carbohydrates for constructive exploitation. During the past decades, diverse lignin degrading enzymes were characterized to facilitate the utilization of lignocellulosic bioma...

In recent years long chain fatty acids have been shown to be the principal metabolic fuel of the adult heart (1-3). For the tissues of the mammalian fetus, however, carbohydrates rather than lipids appear to serve as the primary source of energy (4, 5). This difference in energy metabolism related to maturation suggested that the heart of the newborn, in contrast to that of the adult, might be ...