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Seven different in vitro methods to determine the protein digestibility for chickpea proteins were considered and also the application of these methodologies for calculating PDCAAS (protein digestibility-corrected amino acid score), seeking their correlations with the in vivo methodology. In vitro digestibility of raw and heated samples were determined using pepsin-pancreatin hydrolysis, considering soluble nitrogen via Kjeldahl (ppKJ) and hydrolysed peptide linkages using trinitrobenzenesulfonic acid and o-phthaldialdehyde. In vitro digestibility was also determined using trypsin, chymotrypsin and peptidase (3-Enz) or trypsin, chymotrypsin, peptidase and pronase solution (4-Enz). None of the correlations between in vitro and in vivo digestibilities were significant (at p < 0.0500), but, strong correlations were observed between PDCAAS calculated by in vitro and in vivo results. PDCAAS-ppKJ, PDCAAS-3-Enz and PDCAAS-4-Enz presented the highest correlations with in vivo method, r = 0.9316, 0.9442 and 0.9649 ( p < 0.0500), respectively. The use of in vitro methods for calculating PDCAAS may be promising and deserves more discussions. [ABSTRACT FROM AUTHOR]

The article presents a study discussing the action of the protein administered orally as a dietary supplement to rats fed a hypercholesterolemic diet. Topics discussed include risk factors for cardiovascular disease, the action of gastrointestinal enzymes, and excretion of cholesterol due to the interaction of peptides with bile salts.

Abstract: The chickpea vicilin-like globulin was isolated and chromatographed on Sepharose CL-6B and Sephacryl S-300. The native globulin with a molecular weight of 140kDa was resolved in Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in seven polypeptide bands in the range of 12.4–67kDa. The solubility profile of the protein in water and NaCl solutions was typical of a legume globulin. The purified vicilin-like globulin, native and heated, was hydrolyzed by pepsin, trypsin and chymotrypsin. The hydrolysis patterns indicated that the native vicilin-like protein was only partially degraded by the enzymes in comparison with casein. Heating increased its susceptibility to hydrolysis relative to the native form, for all the enzymes. However, the results obtained by the pH-drop method revealed that the in vitro digestibility of the vicilin-like protein was not altered by heating, while 11S-like and total globulins suffered a small increase, indicating that the structural characteristics of storage globulins may be important factors limiting the protein digestion. [Copyright &y& Elsevier]

Highlights: [•] This study indicates that Moringa oleifera leaves have a high nutritional value. [•] The existing total protein in the leaves showed low in vitro digestibility. [•] It can be used as a source of dietary protein; however in vivo studies are needed. [•] Antinutritional substances tested are very low and no cyanogenic compounds were found. [ABSTRACT FROM AUTHOR]

Purpose The hypocholesterolemic activity of legume vicilins and the structural homology among mung bean, soybean and adzuki bean vicilins (8S) suggest that this protein may play a role in lipid metabolism. Thus, in the present study, the authors aim to isolate the mung bean vicilin and assess its in vitro effect on 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG CoAr), the enzyme responsible for endogenous cholesterol synthesis.Design/methodology/approach Chromatographic and electrophoretic characterization identified the molecular mass and polypeptide composition of mung bean vicilin. The hydrolysate of this globulin was obtained by sequential hydrolysis with pepsin-pancreatin and the fragments were characterized by molecular filtration, SDS PAGE and HPLC.Findings The molecular mass of vicilin was estimated as 158.23 at ± 10 kDa and SDS-PAGE revealed that the 8S globulin protein comprises four bands corresponding to polypeptides of 61, 48, 29 and 26 kDa. Fractions 10, 12, 14, 22 and 32 of the eluate from Sephadex G-25 exhibited significant inhibition of HMG CoAr.Originality/value The correspondence of the chromatographic profile of the peptide fractions with hypocholesterolemic activity suggests that the composition and chemical structure of these peptides are essential to their physiological effectiveness. The beneficial effects of mung bean vicilin identified in this study will support the characterization of this protein as a functional compound. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to determine the effects of isolated soy glycinin (11S) on lipid metabolism in animals subjected to a hypercholesterolemic diet. Design/methodology/approach – Male Wistar rats were kept in individual cages under appropriate conditions. The animals were divided into three groups (n=9): normal diet (STD) given a diet containing casein as protein source, recommended in AIN-93M; hypercholesterolemic (HC) fed a normal diet with 1 per cent cholesterol and 0.5 per cent cholic acid; and hypercholesterolemic+glycinin (HC+11S), fed a hypercholesterolemic diet, plus 11S soy protein (300 mg/kg/day), dissolved in saline and administered by gavage. After 28 days, the animals were sacrificed and blood and liver removed for biochemical analysis of total cholesterol (TC), HDL-cholesterol (HDL-C) and triglycerides (TG) in the plasma, hepatic TC and TG. Findings – A single daily dose of glycinin given to the hypercholesterolemic group demonstrated its functional role, particularly in raising HDL-C and reducing triglycerides in the liver. Originality/value – This study demonstrates the action of the 11S globulin in soybean as a serum lipid lowering agent, in addition to its nutritional properties, especially in raising the HDL-C. [ABSTRACT FROM AUTHOR]

ABSTRACT Polyphenoloxidase (PPO) from atemoya fruit was extracted and partially purified by phase partitioning in Triton X-114 (TX-114), ammonium sulfate precipitation and separation on Sephadex G-100. Polyacrylamide gel electrophoresis of the fraction eluted from Sephadex revealed only one band of enzyme activity with a molecular weight of 82 kDa. The achieved purification was 7.12-fold with a recovery of 3.2%. The optimum pH and temperatures were determined for 4-methylcatechol and catechol, and activation energies (Ea) determined. The Km was 5.52 and 79.3 mmol/L for 4-methylcatechol and catechol, respectively. The enzyme showed no activity with L-dihydroxyphenilalanine, pyrogallol, catechin and P-cresol as substrates. Inhibitory effects of phenolic and non-phenolic compounds were tested and the Ki values and type of inhibition determined. Enzyme showed to be relatively unstable at 55-70C and Ea for heat inactivation was determined. NaCl and KCl showed to be protective agents of atemoya PPO against thermal denaturation. PRACTICAL APPLICATIONS Atemoya ( Annona cherimola Mill. × Annona squamosa L.) is a fruit which has excellent sensorial characteristics and that comes reaching high commercial value. However, these fruits are an excellent example of fruit susceptible to enzymatic browning, and this is a problem encountered during handling and processing. The quality of fruits, especially atemoya, depends on controlling the enzymatic browning. Addition of chemicals, pH adjustment, refrigeration, thermal treatments and exclusion of oxygen are among the most effective methods for the inhibition of browning, and their application to a product will depend of the characteristic properties of the enzymes related to browning. The main enzyme involved in browning is polyphenoloxidase (PPO), however, research on fruit enzymes is necessary and there is little information on the properties of PPO from atemoya fruit. Accordingly a wide knowledge of the biochemical properties of fruit PPO can provide support for planning and strategies to reduce browning. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the comparative hypocholesterolemic effect of soybean 7S fraction in rats fed a high-cholesterol diet. Soybean 7S globulin ([beta]-conglycinin) was administered orally once a day to rats, and the effects were measured after 28 days. Wistar rats were divided into four groups: standard diet (STD) (casein alone), hypercholesterolemic (HC) diet (STD plus 1 g/100 g cholesterol and 0.5 g/100 g cholic acid), HC+7S(1) diet (HC diet plus 200 mg of 7S/kg of body weight/day), and HC+7S(2) diet (HC diet plus 300 mg of 7S/kg of body weight/day). Food intake, weight gain, animals' growth, and feeding efficiency ratio were similar among the STD and three HC groups, indicating that these parameters were not affected by treatments. Animals that had received different doses of soybean 7S globulin had lower total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL)/high-density lipoprotein (HDL) ratio in serum and lower levels of hepatic TC and TG than those fed only the HC diet. The atherogenic indexes of HC+7S(1) and HC+7S(2) groups were 40% and 55% lower than that of the HC group, respectively. The results showed that the oral daily administration of [beta]-conglycinin in the diet to HC rats, at between 1.85% and 2.75% of total ingested protein, promotes the reduction of TC, LDL-cholesterol, and TG and an increase in HDL-cholesterol in the plasma, besides a small but significant reduction in cholesterol and TG levels in the liver of the animals as well as a reduced atherogenic index. [ABSTRACT FROM AUTHOR]