Ponnusamy Ponmurugan

Antihyperglycemic and antioxidant effects of Solanum xanthocarpum leaves (field grown & in vitro raised) extracts on alloxan induced diabetic rats

OBJECTIVE To investigate antidiabetic efficacy of the extract of field grown and in vitro raised leaves of Solanum xanthocarpum (S. xanthocarpum) against alloxan induced diabetic rats. METHODS The antidiabetic activity of the crude methanol extracts of the field grown and in vitro raised leaves of S. xanthocarpum at different concentrations (100-200 mg/kg bw) was tested against alloxan induced diabetic rats. The antidiabetic efficacy was validated through various biochemical parameters and the antioxidant effect was also determined. The phytochemical analyses of field grown S. xanthocarpum and in vitro rasied S. xanthocarpum leaves were done by estimating their chlorophyll, carotenoids, total sugar, protein, amino acid and minerals contents. RESULTS The results revealed that the methanol extracts of both the leaves (field grown and in vitro raised) of S. xanthocarpum was efficient anti hyperglycemic agents at a concentration of 200 mg/kg bw and posses potent antioxidant activity. However, the extracts of in vitro rasied S. xanthocarpum raised leaves exhibit higher efficacy than the field grown leaves in all tested concentrations. Proximal composition and mineral analysis of S. xanthocarpum revealed higher concentration of contents in in vitro rasied S. xanthocarpum than field grown S. xanthocarpum. CONCLUSIONS From the results it can be concluded that the leaves extracts of S. xanthocarpum can be a potential candidate in treating the hyperglycemic conditions and suits to be an agent to reduce oxidative stress.

Anti‐obesity action of gingerol: effect on lipid profile, insulin, leptin, amylase and lipase in male obese rats induced by a high‐fat diet

BACKGROUND Obesity represents a rapidly growing threat to the health of populations and diet intervention has been proposed as one of the strategies for weight loss. Ginger and its constituents have been used for their anti-flatulent, expectorant and appetising properties and they are reported to possess gastro-protective and cholesterol-lowering properties. The present study investigated the effects of gingerol on the changes in body weight, serum glucose, insulin, insulin resistance and lipid profile in plasma and liver as well as on the activity of amylase, lipase and leptin in high-fat diet (HFD)-induced obese rats. RESULTS HFD-induced obese rats were treated orally with gingerol (25, 50 and 75 mg kg(-1) ) once daily for 30 days. A lorcaserin-treated group (10 mg kg(-1) ) was included for comparison. The levels of body weight, glucose, lipid profile and insulin, insulin resistance, leptin, amylase and lipase were increased significantly (P < 0.05) in HFD rats. Rats treated with gingerol and fed a HFD showed significantly (P < 0.05) decreased glucose level, body weight, leptin, insulin, amylase, lipase plasma and tissue lipids when compared to normal control. The effect at a dose of 75 mg kg(-1) of gingerol was more pronounced than that of the dose 25 mg kg(-1) and 50 mg kg(-1) . The lorcaserin-treated group also manifested similar effects to those of gingerol. CONCLUSION These findings suggested that ginger supplementation suppresses obesity induced by a high fat diet and it might be a promising adjuvant therapy for the treatment of obesity and its complications.

Evaluation of fungicides and biocontrol agents against Phomopsis canker of tea under field conditions

An experiment was conducted to study the efficacy of contact and systemic fungicides and biocontrol agents in controlling Phomopsis canker disease of tea under field conditions. Among the various treatments, soil application and wound dressing of biocontrol agents was found to be superior to fungicides in controlling Phomopsis canker. Dressing wounds with contact fungicides such as copper oxychloride and mancozeb was found ineffective whereas drenching soil with systemic fungicides such as carbendazim and contaf was moderately effective. Various treatments healed wounds to varying degrees and improved plant health. The bud break, tipping weight and green leaf yield were also increased to some extent in plants after treatments. Among the biocontrol agents tested, Gliocladium virens was better than Trichoderma harzianum in terms of curing cankers and increasing yield potential. The initial carbohydrate level of 9.38% increased with various treatments and was increased to 15.18% in cut-across pruned plants treated by soil application and wound dressing using G. virens. Similarly, the initial carbohydrate level of 9.15% increased to 11.89% when rejuvenated plants (pruned to healthy tissue) were treated with G. virens. In the case of the untreated control, the canker size increased from 6.37 by 2.24 cm to 8.57 by 3.17 cm and the plants appeared unhealthy with yellowing of the leaves and stunted growth associated with heavy flowering.

Antidiabetic effect of S-allylcysteine: Effect on Thyroid hormone and circulatory antioxidant system in experimental diabetic rats

OBJECTIVE It is considered that diabetes mellitus and thyroid disease are the two common endocrine disorders and also suggested that insulin and thyroid hormones influence each other actions. The present study was designed to investigate the effect of the administration of S-allylcysteine (SAC), a sulfur containing amino acid derived from garlic on blood glucose, insulin, HbA1C, total protein, albumin, Thyroid hormone (T3, T4), TSH, TBARS and circulatory antioxidant levels (SOD, CAT, GSH and GPx) in STZ-induced diabetic rats. METHODS SAC was administered orally for 45 days to control and STZ induced diabetic rats. The effects of SAC on glucose, plasma insulin, HbA1C, total protein, albumin, Thyroid hormone, TSH and circulatory antioxidant levels were studied. RESULTS The levels of glucose, TBARS, hydroperoxide and HbA1C were increased significantly whereas the levels of plasma insulin, reduced glutathione, superoxide dismutase, catalase, GSH, GPx, total protein, albumin, Thyroid hormone and TSH were decreased in STZ induced diabetic rats. Administration of SAC to diabetic rats showed a decrease in plasma glucose, TBARS, hydroperoxide and HbA1C. In addition, the levels of plasma insulin, SOD, CAT, GPx, GSH, total protein, albumin, Thyroid hormone and TSH were increased in SAC treated diabetic rats. The effect of SAC was compared with gliclazide, a well-known antioxidant and antihyperglycemic drug. CONCLUSION From these findings, it is indicated that SAC might be acting through activation in the synthesis and/or secretion of circulating thyroid hormones which in turn stimulate the synthesis of insulin.

Diosgenin reorganises hyperglycaemia and distorted tissue lipid profile in high-fat diet-streptozotocin-induced diabetic rats.

BACKGROUND Diabetes is often connected with significant morbidity, mortality and also has a pivotal role in the development of cardiovascular diseases. Diet intervention, particularly naturaceutical antioxidants have anti-diabetic potential and avert oxidative damage linked with diabetic pathogenesis. The present study investigated the effects of diosgenin, a saponin from fenugreek, on the changes in lipid profile in plasma, liver, heart and brain in high-fat diet-streptozotocin (HFD-STZ)-induced diabetic rats. Diosgenin was administered to HFD-STZ induced diabetic rats by orally at 60 mg kg(-1) body weight for 30 days to assess its effects on body weight gain, glucose, insulin, insulin resistance and cholesterol, triglycerides, free fatty acids and phospholipids in plasma, liver, heart and brain. RESULTS The levels of body weight, glucose, insulin, insulin resistance, cholesterol, triglycerides, free fatty acids, phospholipids, VLDL-C and LDL-C were increased significantly (P < 0.05) whereas HDL-C level decreased in the HFD/STZ diabetic rats. Administration of diosgenin to HFD-STZ diabetic rats caused a decrease in body weight gain, blood glucose, insulin, insulin resistance and also it modulated lipid profile in plasma and tissues. CONCLUSION The traditional plant fenugreek and its constituents mediate its anti-diabetic potential through mitigating hyperglycaemic status, altering insulin resistance by alleviating metabolic dysregulation of lipid profile in both plasma and tissues.

Modulatory Effects of Diosgenin on Attenuating the Key Enzymes Activities of Carbohydrate Metabolism and Glycogen Content in Streptozotocin-Induced Diabetic Rats

OBJECTIVE Fenugreek and its active compound diosgenin are ancient herbal medicines recommended by the World Health Organization. In this study, the effect of diosgenin on changes in carbohydrate metabolic enzymes and glycogen content in muscle and kidneys of streptozotocin-induced diabetes rats were evaluated. METHODS Diabetes was induced in male albino Wistar rats by intraperitoneal administration of streptozotocin. The diosgenin at different doses (15, 30 and 60 mg/kg body weight) was administered orally to normal and streptozotocin-diabetic rats for 45 days. RESULTS Streptozotocin intoxication led to a significant increase (p<0.05) in blood glucose and a decrease in insulin levels. The carbohydrate metabolic enzymes and glycogen content were also altered. The daily oral administration of diosgenin at different doses (15, 30 and 60 mg/kg body weight) to diabetic rats for 45 days resulted a significant (p<0.05) decline in blood glucose level and a significant increase in plasma insulin level. The altered activities of carbohydrate metabolic key enzymes in muscle and kidneys of diabetic rats were significantly (p<0.05) reverted to near normal level by the administration of diosgenin. The obtained results were compared with glibenclamide, a standard oral hypoglycemia drug. CONCLUSIONS The modulatory effects of diosgenin on attenuating the activities of carbohydrate metabolic enzymes afford a promise for persistent use for the treatment of diabetes in the future, even though clinical studies to evaluate this possibility may be warranted.

CULTURE AND BIOCHEMICAL ANALYSIS OF A TEA ALGAL PATHOGEN, CEPHALEUROS PARASITICUS

To assess the current situation regarding the incidence of red rust disease in tea plants, an extensive survey was conducted in southern Indian tea plantations covering different tea cultivars and agroclimatic zones. The results indicated that the incidence of disease was more severe in tea seedlings than clones in all the agroclimatic zones. On the other hand, a simple, reliable, and reproducible technique was standardized for culturing Cephaleuros parasiticus G. Karst. isolated from infected tea leaves. Ten isolates were obtained, of which two were screened based on growth rate and culture characters for further studies. Ten culture media were tested for the culturing of C. parasiticus in which Trebouxia and Bristol media were the best followed by George, Go algal, and tea leaf extract media. Variations between isolates (Valparai C. parasiticus field number 27 [VCP27], Munnar C. parasiticus field number 11 [MCP11], and University of Texas culture number 2412 [UTEX2412]) of C. parasiticus were studied based on the growth pattern, protein expression profile, and cellular constituents in the filaments. The quantitative estimation of cellular constituents showed that there was no significant difference in these constituents among isolates. The detection of amino acids in the filaments of C. parasiticus isolates showed 16 free forms and 11 bound forms. Amino acids in bound form were higher in all the isolates than in free form of amino acids. The three isolates of C. parasiticus were closely related, with bands lying between the molecular weight of 116 and 35 kDa.

Antifungal activity of biosynthesised copper nanoparticles evaluated against red root-rot disease in tea plants

ABSTRACT The synthesis of metal nanoparticles is an emerging area of advanced research and technology with potential application in plant protection. In the current study, with an eco-friendly approach, a convenient method was adopted, where copper nanoparticles are biosynthesised extracellularly by using Streptomyces griseus. Further, the existence of nanoparticles was confirmed by UV–visible spectroscopy, transmission electron microscopy, X-ray diffraction analysis and Fourier transform infrared spectroscopy characterisation. We assessed the field effectiveness of copper nanoparticles through soil application in P. hypolateritia infested tea plants. In response to seven different treatments, carbendazim exhibited superior control followed by nanocopper at 2.5 ppm dosage. However, maximum leaf yield was observed in plants treated with nanocopper. In addition, nanocopper-treated plants showed improved soil macronutrients considerably when compared to bulk copper and carbendazim treated plants. In addition, there was trivial variation in population dynamics of microbes noted in plants treated with nanocopper. These encouraging results confirmed that nanocopper could act as an efficient novel fungicide which may be used for the management of red root-rot disease in tea plantations.

Effect of S-allylcysteine, a sulphur containing amino acid on iron metabolism in streptozotocin induced diabetic rats.

It is suggested that iron may play a role in the pathogenesis of diabetes. Iron is not only chaperoned through its essential functional pathways, but it also causes damage to biological systems by catalyzing the production of reactive oxygen species. So, the parenchymal tissues of several organs are subject to cell injury and functional insufficiency due to excess deposition of iron. The present study investigated the effects of S-allylcysteine (SAC), a sulphur containing amino acid derived from garlic on the changes in iron metabolism induced by oxidative stress in tissues, as well as on serum biochemical parameters of streptozotocin (STZ)-induced diabetic rats. SAC was administered orally for 45days to control and experimental diabetic rats. The effects of SAC on glucose, insulin, serum iron, ferritin, transferrin, serum bilirubin, heart heme oxygenase activity (HO) and δ-aminolevulinicacid dehydratase activity (δ-ALA-D) in liver and kidneys were studied. The levels of glucose, iron, ferritin, bilirubin and HO in liver were increased significantly (p<0.05) whereas the levels of insulin, transferrin and δ-ALA-D in tissues were decreased in diabetic rats. Administration of SAC to diabetic rats showed a decrease in blood glucose, iron, ferritin, bilirubin and HO. In addition, the levels of insulin, transferrin and δ-ALA-D activity in tissues were increased in SAC treated diabetic rats. These findings suggest that S-allylcysteine could have a protective effect against alterations in oxidative stress induced iron metabolism in the diabetic state which was evidenced by the capacity of this natural antioxidant to modulate parameters of iron metabolism.

Two new species of saxicolous Pyxine with yellow medulla from southern India

Abstract: Two new species of Pyxine with yellow medulla from saxicolous habitats are described asnew to science. The new species P. punensis has an isidiate, UV+ yellow thallus with 0 3–0 6mmwide lobes. Pyxine yercaudensis has smaller ascospores (13–16 6–7mm), lacks vegetative propagulesand lacks lichexanthone.Key words: Dirinaria, Eastern Ghats, lichens, Physciaceae, taxonomyAccepted for publication 23 August 2012 IntroductionThe lichen genus Pyxine was established byElias Fries in 1825 and it is a prominentmember of the family Physciaceae. The genusis characterized by closely appressed, radiat-ing, whitish to bluish grey, foliose thalli withnarrow lobes often covered with pruina,maculae and pseudocyphellae. The apothe-cia have a lecanorine to lecidine margin, K+purple epihymenium, hyaline hymenium andbrown hypothecium. Ascospores are mostly2-celled, brown, thick-walled, ellipsoidaland mischblastiomorphic-type. Pyxine is veryclose to Dirinaria, which can be differentiatedby the absence of rhizines (placodioid condi-tion),K-- epihymenium,andmedullarychem-istry. Molecular phylogenetic studies haveshown that there is a close relationship be-tween these two genera but they are clearlyseparated as distinct lineages (Helms et al.2003). In Pyxine, the colour of the medullacan range from white to stramineous orsometimes distinctly yellow or orange ochra-ceous and it plays an important role in thetaxonomyofthegenus.Thespecies ofPyxinemostly contain atranorin and several un-identified terpenes as secondary metabolites.Some species contain lichexanthone ratherthan atranorin and such thalli emit a cream-ish, yellow fluorescence when viewed underlong wavelength ultraviolet light (350 nm).The genus Pyxine is mainly pantropicalto subtropical with several species extendinginto temperate or oceanic regions, and com-prises c. 65 species (Elix 2009). Index Fun-gorum (www.indexfungorum.org) holds atotal of 162 records for Pyxine,which include96 species and several infra-specific taxa.However, many taxa in that list need valida-tion (e.g. P. consocians Vain. is mentioned assynonym of P. subcinerea Stirt.). A number ofstudies on Pyxine throughout the world areavailable. Swinscow & Krog (1975) reported23 species from East Africa. Initially Rogers(1986) studied Pyxine from Australia butthis treatment was later updated by Kalb(1994) and Elix (2009), where 26 specieswere reported. Amtoft (2002) studied Pyxinefrom the eastern United States, Imshaug(1957) from North and Middle America,Kalb(2001)fromtheGreaterSonoranDesertRegion, Hu & Chen (2003) from China,Moberg (1983) from Europe and Kashiwa-dani (1977a, b, c) from Japan. Obermayer &