Ummiti Js Prasada Rao

Presence of an acidic glycoprotein in the serum of arthritic rats: modulation by capsaicin and curcumin.

Levels of various serum proteins were found to change in adjuvant induced arthritis. Increased levels of a glycoprotein with an apparent molecular weight of 72 kDa (Gp A72) were observed in the sera of arthritic rats. Gp A72 is an acidic glycoprotein with a pI of 5.1. Gp A72 also showed antitryptic activity. The appearance of Gp A72 in the serum preceded the onset of paw inflammation in arthritic rats and persisted in the chronic phase. Oral administration of the antiinflammatory spice principles-capsaicin (from red pepper) and curcumin (from turmeric) lowered the levels of Gp A72 by 88 and 73% respectively with concomitant lowering of paw inflammation in arthritic rats.

Anti-diabetic effect of dietary mango (Mangifera indica L.) peel in streptozotocin-induced diabetic rats

BACKGROUND In the present study, the composition of mango peel powder (MPP) collected from the mango pulp industry was determined and the effect of MPP on ameliorating diabetes and its associated complications was studied. RESULTS Mango peel was rich in polyphenols, carotenoids and dietary fibre. Peel extract contained various bioactive compounds and was found to be rich in soluble dietary fibre. Peel extract exhibited antioxidant properties and protected against DNA damage. Therefore, the effect of peel on ameliorating diabetes was investigated in a rat model of diabetes. A significant increase in urine sugar, urine volume, fasting blood glucose, total cholesterol, triglycerides and low density lipoprotein, and decrease in high density lipoprotein were observed in the rats; however, these parameters were ameliorated in diabetic rats fed with diet supplemented with mango peel at 5% and 10% levels in basal diet. Treatment of diabetic rats with MPP increased antioxidant enzyme activities and decreased lipid peroxidation in plasma, kidney and liver compared to untreated diabetic rats. Glomerular filtration rate and microalbuminuria levels were ameliorated in MPP treated diabetic group. CONCLUSIONS Mango peel, a by-product, can be used as an ingredient in functional and therapeutic foods.

Protection of DNA and erythrocytes from free radical induced oxidative damage by black gram (Vigna mungo L.) husk extract.

Antioxidants present in various plant tissues exhibit health benefits by scavenging reactive oxygen species generated under various pathophysiological conditions. In the present study, bioactive compounds from black gram husk were extracted with water and the protection of black gram husk (BGH) extract against oxidative damage in DNA and erythrocytes were studied. BGH extract had total polyphenol content of 59 mg of gallic acid equivalents (GAE). The phenolic acids identified in the extract using RP-HPLC were gallic, protocatechuic, gentisic and ferulic acids. The extract showed good antioxidant properties. The IC(50) value for DPPH radical scavenging activity was found to be 3.92 μg of GAE. The BGH extract also showed α-glucosidase inhibition and the IC(50) value was found to be 2.78 μg of GAE. The oxidative hemolysis caused by hydrogen peroxide in rat erythrocytes was inhibited by BGH extract in a dose dependent manner. The IC(50) values for BGH extract and BHA for hemolysis were 11.5 and 14 μg of GAE, respectively. Morphological changes in erythrocyte membrane caused by hydrogen peroxide were protected by BGH extract. As BGH extract exhibited various antioxidant properties in different systems, it could be used as a functional food or nutraceutical product for health benefits.

Role of advanced glycation on aggregation and DNA binding properties of α-synuclein.

Parkinsons disease (PD) is a neurodegenerative disease with multiple etiologies. Advanced glycation end products (AGEs) accumulate in the aging brain and could be one of the reasons for age-related diseases like PD. Oxidative stress also leads to the formation of AGEs and may be involved in neurodegeneration by altering the properties of proteins. α-Synuclein is involved in pathogenesis of PD and there are limited studies on the role of AGE-α-synuclein in neurodegeneration. We studied the aggregation and DNA binding ability of AGE-α-synuclein in vitro. α-Synuclein is glycated using methylglyoxal and formation of AGE-α-synuclein is characterized using fluorescence studies, intrinsic tyrosine fluorescence, and fructosamine estimation. The results indicated that AGE-α-synuclein aggregates into smaller globular-like aggregates compared to fibrils formed with native α-synuclein. Further, it is found that AGE-α-synuclein induced conformational changes in scDNA from B-form to B-C-A mixed conformation. Additionally, AGE-α-synuclein altered DNA integrity as evidenced by the melting temperature, ethidium bromide, and DNAse I sensitivity studies. AGE-α-synuclein converted biphasic Tm to higher monophasic Tm. The Tm of AGE-α-synuclein-scDNA complex is more than that of native α-synuclein-scDNA complex, indicating that AGE-α-synuclein stabilized the uncoiled scDNA. AGE-α-synuclein could stabilize the uncoiled scDNA, as shown by the decrease in the number of ethidium bromide binding molecules per base pair of DNA. DNAse I sensitive studies indicated that both AGE-α-synuclein-scDNA and α-synuclein-scDNA are resistant to DNAse I digestion. The relevance of these findings to neuronal cell death is discussed.

Indian Wheat Cultivars: Correlation between Quality of Gluten Proteins, Rheological Characteristics of Dough and Tandoori Roti Quality

Physico-chemical, rheological characteristics and quality of tandoori roti were determined for whole wheat flours from eight commercial wheat cultivars grown at one location. Tandoori roties baked from these flours indicated wide differences in baking performance. Among the varieties, Cpan-3004, GW-180 and K-8804 and WL-1562 were found suitable for the preparation of tandoori roti. These four varieties had higher water absorption capacity (718–735 ml kg-1) when measured in a farinograph at an optimum tandoori dough consistency of 400 BU. The doughs from these varieties also had higher cohesiveness (0·38–0·45) and extensibility (114–121 mm) than other varieties. Total protein, gluten as well as total glutenin (soluble and insoluble) contents were found to be maximum in these four varieties. Varieties having Glu-1 score of 6 were found to be more suitable for roti preparation. The prediction equation derived for correlating total protein and total glutenin in flour with overall sensory score of roti was found highly significant (R2 = 0·92). The results suggest that the medium hard wheats are suitable for the preparation of tandoori roti.

Enhancement of soluble dietary fibre, polyphenols and antioxidant properties of chapatis prepared from whole wheat flour dough treated with amylases and xylanase

BACKGROUND Chapati preparation involves various processing steps such as mixing the flour into dough, sheeting and baking. During these processing steps, flour components are likely to undergo changes in their nutrient and polyphenol composition and their antioxidant properties due to phenol-mediated crosslinking of proteins and carbohydrates. Therefore, in the present study, changes in nutritional, nutraceutical and antioxidant properties of chapatis prepared from doughs treated with amylases and xylanase were determined. RESULTS An increase in insoluble dietary fibre content and a decrease in soluble polyphenol content were observed during preparation of control chapatis from whole wheat flours. However, significant increases in soluble dietary fibre and soluble polyphenol contents were observed in chapatis prepared from amylase-treated doughs compared with control chapatis. Extracts of chapatis prepared from amylase- and xylanase-treated doughs showed better antioxidant properties than extracts of control chapatis. Among these enzyme treatments, chapatis prepared from amylase-treated doughs showed better antioxidant properties than chapatis prepared from xylanase-treated doughs. High-performance liquid chromatography analysis of extracts of chapatis prepared from doughs treated with amylases showed the presence of potential antioxidant phenolic acids such as caffeic, gentisic and syringic acids in addition to the phenolic acids present in control chapatis. CONCLUSION Treatment of doughs with amylases increased the contents of soluble dietary fibre and soluble polyphenols as well as improving the antioxidant properties of chapatis.

Protein glycation and aggregation inhibitory potency of biomolecules from black gram milled by-product

BACKGROUND Persistent hyperglycaemia causes increased advanced glycation end products (AGEs), which contribute to the pathogenesis of diabetic complication. Therefore, effect of black gram milled by-product (BGBP) extract on inhibition of AGE formation in a bovine serum albumin (BSA)/glucose system was investigated. RESULTS BGBP extract had a total polyphenol content of 82 mg GAE g-1 and flavonoid content of 46 mg CE g-1 . Ferulic acid, protocatechuic acid, gallic acid, gentisic acid, isovitexin, vitexin and epicatechin were the major bioactives in the extract. BGBP extract exhibited an effective Fe2+ chelating activity. Size exclusion-high-performance liquid chromatographic studies indicated that upon BSA-AGE formation the BSA monomer content was 38%; however, in the presence of BGBP extract at 50 and 100 µg levels, the monomer content increased and it was found to be 48% and 73%, respectively. BGBP extract at 50 and 100 µg levels decreased the protein carbonyl and fructosamine contents, and quenched the fluorescence intensity of glycated BSA in a dose-dependent manner. Further, fluorescence and transmission electron microscopic studies confirmed the decrease in formation of AGEs by BGBP extract. CONCLUSION As BGBP extract inhibited the formation of AGEs, the extract can be used as a nutraceutical or it can be incorporated into food products to obtain functional foods.

Purification and characterization of peroxidasefrom sprouted green gram (Vigna radiata) rootsand removal of phenol and p-chlorophenol byimmobilized peroxidase.

BACKGROUND Peroxidase activity was increased during germination of green gram and such an increase may have benefits in many physiological processes. The present study aimed to investigate the optimum conditions for the extraction, purification and characterization of peroxidase from the germinated green gram roots and also its application for the removal of phenols in water. RESULTS Peroxidase activity was increased by 300-fold in 5-day germinated green gram. Because the root was rich in peroxidase activity, peroxidase from roots was isolated and purified to homogeneity. The purified peroxidase showed a single band on sodium dodecyl sulphate-polyacrylamide gel electrophoresis with a molecular weight of 50 kDa, an optimum pH of 5.5 and a pH stability ranging from 5 to 9. The enzyme had 50% residual activity at 70 °C. It catalyzed the oxidation of a variety of substrates. The Km value of the enzyme was 1.28 mmol L-1 for o-dianisidine and 0.045 mmol L-1 for H2 O2 . The enzyme lost 100% activity in the presence of dithiothreitol and cysteine. The addition of copper ion increased the enzyme activity by three-fold. Both soluble and immobilized peroxidases removed more phenol than p-chlorphenol, whereas horseradish peroxidase removed more p-chlorphenol. Thus, the green gram root peroxidase showed good pH and temperature stability, as well as the ability to remove phenolic compounds from effluent. CONCLUSION Peroxidase with good thermal and pH stability was purified from germinated green gram roots and has the ability to oxidize phenolic compounds from waste water.

Evaluation of Cassia tora Linn. against oxidative stress-induced DNA and cell membrane damage

Objective: The present study aims to evaluate antioxidants and protective role of Cassia tora Linn. against oxidative stress-induced DNA and cell membrane damage. Materials and Methods: The total and profiles of flavonoids were identified and quantified through reversed-phase high-performance liquid chromatography. In vitro antioxidant activity was determined using standard antioxidant assays. The protective role of C. tora extracts against oxidative stress-induced DNA and cell membrane damage was examined by electrophoretic and scanning electron microscopic studies, respectively. Results: The total flavonoid content of CtEA was 106.8 ± 2.8 mg/g d.w.QE, CtME was 72.4 ± 1.12 mg/g d.w.QE, and CtWE was 30.4 ± 0.8 mg/g d.w.QE. The concentration of flavonoids present in CtEA in decreasing order: quercetin >kaempferol >epicatechin; in CtME: quercetin >rutin >kaempferol; whereas, in CtWE: quercetin >rutin >kaempferol. The CtEA inhibited free radical-induced red blood cell hemolysis and cell membrane morphology better than CtME as confirmed by a scanning electron micrograph. CtEA also showed better protection than CtME and CtWE against free radical-induced DNA damage as confirmed by electrophoresis. Conclusion: C. tora contains flavonoids and inhibits oxidative stress and can be used for many health benefits and pharmacotherapy.

Diet-induced hypercholesterolemia alters liver glycosaminoglycans and associated-lipoprotein receptors in rats

Glycosaminoglycans (GAGs) play an important role in lipoprotein metabolism. In liver, it facilitates the uptake of remnants through receptor-independent endocytosis. However, changes in liver GAGs during diet-induced hypercholesterolemia with normal levels of fat feeding are unknown. Present paper highlights the effect of diet-induced hypercholesterolemia with normal levels (5%) of fat on liver GAGs and other associated lipoprotein receptors. Hypercholesterolemia was induced in rats by feeding diet supplemented with 0.5% cholesterol and 0.125% bile salts. Hypercholesterolemia showed significantly decreased GAGs of both heparan sulfate (HS) and chondroitin sulfate/dermatan sulfate (CS/DS) classes of molecules. Quantitative real-time polymerase chain reaction analysis of GAG biosynthetic enzymes and other genes revealed significant changes in expression profile. The decrease in GAGs was prevented by simvastatin treatment; a drug that inhibits endogenous cholesterol synthesis that was used as a positive control in our study. Furthermore, there was a comparatively decreased binding of GAGs from hypercholesterolemic rats to lipoprotein lipase. LRP1 which plays a major role in lipoprotein uptake was also significantly decreased, and it was attenuated in simvastatin-treated hypercholesterolemic rats. Furthermore, LDLR and ApoE were also decreased significantly in liver of hypercholesterolemic rats. Thus, diet-induced hypercholesterolemia results in dysregulation of cholesterol homeostasis apparently through changes in GAGs in conjunction with other associated players.