Nitrosamine Impurities in Herbal Formulations: A Review of Risks and Mitigation Strategies.

Nitrosamines are a class of chemical compounds that have been found to be impurities in a variety of pharmaceutical products. These impurities have raised concerns due to their potential carcinogenic effects. Recent studies have identified nitrosamines as impurities in a number of pharmaceutical products including angiotensin II receptor blockers (ARBs) and proton pump inhibitors (PPIs). The presence of nitrosamines in these products has led to recalls and market withdrawals. In addition to pharmaceuticals, nitrosamines have also been found in some herbal medicines particularly those containing traditional Chinese medicinal ingredients. The presence of nitrosamines in herbal formulations poses a significant risk to public health and highlights the need for quality control and regulations in the herbal drug industry. The present review article aims to discuss nitrosamine impurities (NMI) prominent causes, risks and scientific strategies for preventing NMI in herbal formulations. The primary objective of this study is to examine the origins of nitrosamine contamination in herbal formulations, the risks associated with these contaminants, and the methods for reducing them. The significance of thorough testing and examination before releasing herbal products to the public is also emphasized. In conclusion, the presence of nitrosamines is not limited to pharmaceutical products and poses a significant threat to the safety of herbal drugs as well. Adequate testing and extensive research are crucial for producing and distributing herbal medicines to the general population.

Neurotrophin mimetics and tropomyosin kinase receptors: a futuristic pharmacological tool for Parkinson's.

Parkinson's disease is a complex age-related progressive dopaminergic neurodegenerative disease consistently viewed as a disorder of movement and is characterized by its cardinal motor symptoms. While the motor symptoms and its clinical manifestations are attributed to the nigral dopaminergic neuronal death and basal ganglia dysfunction, studies have subsequently proven that the non-dopaminergic neurons in various brain regions are also additionally involved with the disease progression. Thus, it is now well accepted that the involvement of various neurotransmitters and other ligands accounts for the non-motor symptoms (NMS) associated with the Parkinson's disease. Consequently, this has demonstrated to possess remarkable clinical concerns to the patients in terms of various disability, such impaired to compromised quality of life and increased risk of morbidity and mortality. Currently, available pharmacological, non-pharmacological, and surgical therapeutic strategies neither prevent, arrest, nor reverse the nigral dopaminergic neurodegeneration. Thus, there is an imminent medical necessity to increase patient's quality of life and survival, which in turn decreases the incidence and prevalence of the NMS. The current research article reviews the potential direct involvement of neurotrophin and its mimetics to target and modulate neurotrophin-mediated signal transduction pathways to enlighten a new and novel therapeutic strategy along with the pre-existing treatments for Parkinson's disease and other neurological/neurodegenerative disorders which are associated with the downregulation of neurotrophins.

PEGylation of Nanoemulsion Using Spontaneous Emulsification Method.

Nanoemulsion (NE), a lipid-based drug delivery system, plays an important role in delivering drugs and enhancing bioavailability. They are mainly taken up by the reticuloendothelial system, because of which their bioavailability is diminished, leading to poor therapeutic activity. It is important to protect this delivery system using a coating agent. Thus, we have coated o/w type NE using polyethylene glycol (PEG). The novelty in our study is use of dicarboxylic acid-linked PEG. Furthermore, the spontaneous emulsification method was used in preparation and peg coating, not mentioned previously. After the preparation of NE, various characterization and stability studies were carried out. We have also optimized the ratios for NE and PEG NE by using various concentrations of Smix, PEG, and water. Also, the same has also been plotted in a pseudoternary-phase diagram. As a conclusion, the PEGylation of NE was carried out successfully and may also be used for linking with other ligands because of the presence of COOH group.

Anti-nucleolin Aptamer as a Boom in Rehabilitation of Breast Cancer.

Breast cancer is the second leading cause of cancer-related deaths. It is important to target the complex pathways using a suitable targeted delivery system. Targeted delivery systems can effectively act on cancer cells and lead to the annihilation of tumor proliferation. They mainly employ targeting agents like aptamers linked to the formulation. Based on the expression of the receptors on the surface of the cancer cells, suitable aptamers can be developed. AS1411 is one such aptamer that has the ability to bind to the over-expressed nucleolin present in breast cancer cells. Nucleolin is a phosphoprotein that is involved in various aspects, like cell growth, differentiation and survival. Mostly they are found in the nucleolus, nucleus, cytoplasm and cell surface. The shuttling effect of the nucleolin between the nucleus and cytoplasm serves as a bonus for the AS1411 aptamer. Because of the shutting effect, the internalization of the drug compound or chemotherapeutic drug inside the cell can be achieved. In this article, we have discussed nucleolin, anti-nucleolin aptamer, namely, AS1411, and its application in exhibiting various anticancer activities, including apoptosis, anti-angiogenesis, anti-metastasis, stimulation of tumor suppressor (i.e., P53), and inhibition of tumor inducer. Further, the ways of internalization, namely macropinocytosis, are also discussed. Additionally, we have also discussed the superiority of the aptamer compared to the antibodies as well as the limitations of the aptamers. By considering all the above parameters, we hope this aptamer will be effective in the management and eradication of breast cancer cells.

Glitazones, PPAR-γ and Neuroprotection.

The transcriptional factor PPAR-γ belongs to the nuclear receptor family, which has become a potential therapeutic target for several neurodegenerative diseases and metabolic disorders. Interestingly, PPAR-γ has been reported to have beneficial effects in various chronic neurological conditions via upregulation of its transcriptional co-activator PGC-1α and followed by regulation of multiple molecular events. Although several factors contribute to the progression of neurodegeneration, the dysfunction of PGC-1α expression is primarily interlinked with the pathogenesis of major neurodegenerative diseases. This review gives an insight that ligand-dependent activation of PPAR-γ by glitazones could initiate the structural conformational changes of the secondary proteins, thus recruiting the PGC-1α to form a stable regulatory complex that hampers the various molecular pathways contributing to neurodegeneration. The promising outcomes of the preliminary in silico studies included in this review support that PPAR-γ dependent activation of central PGC-1α signaling by novel glitazones is an encouraging strategy to enhance the oxy-radicals detoxifying system, antiinflammatory responses, and mitochondrial biogenesis required for neuroprotection in various neurodegenerative conditions.

A new pyrimidine alkaloid from the roots of Tadehagi triquetrum (L.) H.Ohashi.

Tadehagi triquetrum (L.) H.Ohashi, also known as Desmodium triquetrum (Fabaceae) is the most important plant in the herbal remedies. The present study focus on the isolation, in-silico and in-vitro studies of the two alkaloids C1 (5-(4-[(methylcarbamoyl) amino]-2-oxopyrimidin-1(2H)-yl) tetrahydrofuran-2-yl) methyl methyl carbamate is novel alkaloid and C2 13-Docosenamide is a known alkaloid. The chemical structures of compounds have been elucidated based on comprehensive techniques like GCMS, IR and NMR. In order to know the molecular mechanisms for the two compounds, in silico molecular docking study has been performed. Both compounds have shown perfect binding affinity to the enzymes TNF α, IL-4, IL-13 and 5 LOX Enzyme. The compounds also exhibited comparable G-scores and Glide energy values in comparison with the standard dexamethasone. In addition both the compounds have been tested for in vitro antioxidant assay by using ABTS and DPPH method and the results were compared with standard ascorbic acid.

Two Rationally Identified Novel Glitazones Reversed the Behavioral Dysfunctions and Exhibited Neuroprotection Through Ameliorating Brain Cytokines and Oxy-Radicals in ICV-LPS Neuroinflammatory Rat Model.

The present study has planned to evaluate the neuroprotective activity of two novel glitazones in a neuroinflammatory rat model. Two novel glitazones were selected from an in-house virtual library of glitazones based on their docking scores against peroxisome proliferator-activated receptor-gamma (PPAR-γ) protein and other parameters studied in in silico computational studies. Initially, an acute oral toxicity study was carried out for glitazones in rats to assess the toxicity profile and to determine the therapeutic range for neuroprotective evaluation. Prior to induction of neuroinflammation, the treatments with glitazones (G1 and G2) and standard pioglitazone were made for four consecutive days to respective groups. On the fifth day, the neuroinflammation was induced by intracerebroventricular (ICV) administration of lipopolysaccharides (LPS) (2 µg/µl) using stereotaxic apparatus. After 7 days, the rats were subjected to behavioral assessment followed by neurobiochemical evaluation and histopathological studies. The pre-treatment with glitazones at two dose levels (15 and 30 mg/kg) has significantly reversed behavioral dysfunctions. Glitazones have shown significant reduction in the levels of LPO, NO, TNF-α, and IL-1ß and also increased the levels of antioxidant enzymes such as SOD, CAT, and GSH in the brain of LPS-administered rats. The neuroprotection exhibited by two novel glitazones is comparable with standard pioglitazone. The PPAR-γ-dependent amelioration of cytokines and oxy-radicals released by novel glitazones during neuroinflammatory conditions may be attributed to the reversal of behavioral dysfunctions through preventing the degeneration of neurons in major regions of the brain.

Minutes of PPAR-γ agonism and neuroprotection.

Peroxisome proliferator-activated receptor gamma (PPAR-γ) is one of the ligand-activated transcription factors which regulates a number of central events and considered as a promising target for various neurodegenerative disease conditions. Numerous reports implicate that PPAR-γ agonists have shown neuroprotective effects by regulating genes transcription associated with the pathogenesis of neurodegeneration. In regards, this review critically appraises the recent knowledge of PPAR-γ receptors in neuroprotection in order to hypothesize potential neuroprotective mechanism of PPAR-γ agonism in chronic neurological conditions. Of note, the PPAR-γ's interaction dynamics with PPAR-γ coactivator-1α (PGC-1α) has gained significant attention for neuroprotection. Likewise, a plethora of studies suggest that the PPAR-γ pathway can be actuated by the endogenous ligands present in the CNS and thus identification and development of novel agonist for the PPAR-γ receptor holds a vow to prevent neurodegeneration. Together, the critical insights of this review enlighten the translational possibilities of developing novel neuroprotective therapeutics targeting PPAR-γ for various neurodegenerative disease conditions.

Pharmacological STING Activation Is a Potential Alternative to Overcome Drug-Resistance in Melanoma.

Melanoma is the most aggressive type of skin cancer and resistance to the conventional chemotherapy is the major cause for its poor prognosis. Metabolic perturbations leading to increased production of reactive oxygen species activate NRF2-dependent anti-oxidative responses to survive oxidative stress. This protective function of NRF2 is the primary cause for therapy resistance in cancer as anti-cancer agents such as BRAF inhibitors also induce NRF2-dependent antioxidative response. We had reported that type I interferons produced upon activation of STING, abrogates NRF2 function. Therefore, we investigated if STING agonists such as the newly developed dimeric aminobenzimidazole (diABZI) could sensitize melanoma cells to the clinically used BRAF inhibitors. Our results reveal that pharmacological activation of STING by diABZI, down regulates NRF2-dependent anti-oxidative responses and potentiates cell-death in melanoma cells when used in combination with BRAF inhibitors.

Isolation and characterization of flavonoids from the roots of medicinal plant Tadehagi triquetrum (L.) H.Ohashi.

Three flavonoid compounds were isolated from the roots of medicinal plant Tadehagi triquetrum (L.) H.Ohashi, also known as Desmodium triquetrum (Fabaceae). On the basis of the chemical and spectral analysis, the compounds were identified as baicalein (Flavone), naringin and neohesperidin (Flavonone). To the best of our knowledge and based on the literature survey all three compounds were first time reported from this medicinal plant.[Formula: see text].

Investigation of Antihyperglycaemic Activity of Banana (Musa sp. Var. Nanjangud rasa bale) Flower in Normal and Diabetic Rats.

BACKGROUND: The vital enzymes of starch digestion and absorption are intestinal α-glucosidases and their inhibition improves postprandial hyperglycaemia, constituting an effective mode of therapy in diabetes. OBJECTIVES: The present study was designed to assess the inhibitory potential of ethanol extract of banana flower (EF) on mammalian α-glucosidases and its pharmacological effects on postprandial hyperglycaemia in normal and alloxan-induced diabetic rats. MATERIALS AND METHODS: EF was evaluated for its inhibitory potential and mode of inhibition on mammalian α-glucosidases. Further, the role of EF and its constituents Umbelliferone (C1) and Lupeol (C2) on glucose uptake using isolated rat hemi-diaphragm and insulinotropic activity using RINm5F (rat insulinoma) cell lines were determined. The phytocomponents in EF were also evaluated using GC-MS. RESULTS: EF illustrated a dose-dependent inhibition for rat intestinal sucrase, maltase and p-nitrophenyl-α-D-glucopyranoside (pNPG) hydrolysis (IC50 values: 18.76±0.22, 25.54±0.10 and 76.42±1.12 µg/ml, respectively) and the mode of inhibition was non-competitive with low Ki values. Oral administration (100-200 mg/kg b.wt.) of EF significantly improved the maltose/glucose-induced postprandial hyperglycaemia in normal and alloxan-induced diabetic rats. EF, C1 and C2 exhibited stimulation of glucose uptake and a dose-dependent glucose-induced insulin secretion at both 4.5 and 16.7 mM glucose concentrations. Further, GC-MS analysis revealed significant levels of steroids (25.61%), diazoprogesterone (21.31%), sesquiterpene (11.78%) and other phytocomponents. CONCLUSION: EF inhibited α-glucosidases besides promoting glucose uptake and insulin secretion, resulting in antihyperglycaemic effect determining EF as a potent anti-diabetic agent.Abbreviations used: mg/dl: milligramsper deciliter, mM: millimolar, b.wt.: body weight.

Cocculus hirsutus: Molecular Docking to Identify Suitable Targets for Hepatocellular Carcinoma by In silico Technique.

BACKGROUND: Protein-ligand interaction plays a major role in identification of the possible mechanism by which a ligand can bind with the target and exerts the pharmacological action. OBJECTIVE: The aim is to identify the best candidate of Cocculus hirsutus which binds with the hepatocellular carcinoma (HCC) targets by docking studies. MATERIALS AND METHODS: The reported phytoconstituents such as coclaurine, hirsutine, cohirsine, cohirsinine, lirioresinol, cohirsitinine, haiderine, jamtinine, isotrilobine, shaheenine, jamtine, and cocsoline present in the plant, C. hirsutus were docked with the HCC targets such as Aurora kinase, c-Kit, fibroblast growth factor, nuclear factor kappa B (NF-kB), B-cell lymphoma-extra large, and vascular endothelial growth factor (VEGF) using in silico technique with the software Grid-Based Ligand Docking with Energies. RESULTS: Haiderine, shaheenine, and coclaurine had good interaction with Aurora kinase with the glide score and glide energy of - 7.632, -7.620, -7.464; and - 56.536, -55.203, -52,822, respectively. Coclaurine, lirioresinol, and haiderine possess good binding with c-Kit with the glide score and glide energy of - 8.572, -6.640, -6.478; and - 56.527, -57.138, -20,522, respectively. Lirioresinol, hirsutine, and coclaurine exhibit good binding with c-Kit with the glide score and glide energy of - 5.702, -5.694, -5.678; and - 48.666, -35.778, -41,673, respectively. Similarly, coclaurine, haiderine, and hisutine had good interaction with NF-kB. Haiderine, jamtinine, and coclaurine had good binding with VEGF receptors (VEGFR) and coclaurine, lirioresinol, and haiderine exhibit good bonding with VEGFR. CONCLUSION: Coclaurine, haiderine, and lirioresinol exibited good hydrogen bonding interactions and binding energy with the select targets. Hence, these compounds have to be taken up for experimental work against hepatocellular carcinoma. SUMMARY: Compounds of interest showed good interaction and binding with the selected targets. Hence these compounds has to be explored further to study their anticancer potentials. Abbreviations used: HCC: Hepatocellular Carcinoma, Bcl-xL: B-cell lymphoma-extra large, FGF: Fibroblast Growth Factor, VEGF: Vascular Endothelial Growth Factor, DLA: Dalton's Lymphoma Ascites.

Isolation of methyl gamma linolenate from Spirulina platensis using flash chromatography and its apoptosis inducing effect.

BACKGROUND: Isolation of methyl gamma linolenate from Spirulina platensis using flash chromatography and its apoptosis inducing effect against human lung carcinoma A- 549 cell lines. METHODS: Gamma linolenic acid is an important omega-6 polyunsaturated fatty acid (PUFA) of medicinal interest was isolated from microalgae Spirulina platensis using flash chromatography system (Isolera system) as its methyl ester. The isolated methyl gamma linolenate was characterized by IR, (1)H NMR, (13)C NMR and mass spectral analysis and the data were consistent with the structure. RESULTS: The percentage yield of isolated methyl gamma linolenate is found to be 71% w/w, which is a very good yield in comparison to other conventional methods. It was subjected to in-vitro cytotoxic screening on A-549 lung cancer cell lines using SRB assay and result was compared with standard rutin. CONCLUSION: It may be concluded that the Flash chromatography system plays a major role in improving the yield for the isolation of methyl gamma linoleate from Spirulina platensis and the isolated molecule is a potent cytotoxic agent towards human lung carcinoma cell lines, however it may be further taken up for an extensive study.

Antioxidant Studies on Ethanol Extracts from Two Selected Genera of Indian Lamiaceae.

The present work is targeted to evaluate antioxidant activity of ethanol extracts from the leaves of Plectranthus mollis and Salvia officinalis belonging to family Lamiaceae using nitric oxide scavenging, hydrogen peroxide scavenging, ferric reducing antioxidant power assay and lipid peroxidation methods. The results of the study indicate that the leaf extracts of both the plants possess in vitro antioxidant activity. The higher amount of flavanoids and phenolic compounds may correspond to their greater antioxidant activity.

Anticancer activity of cissampelos pareira against dalton's lymphoma ascites bearing mice.

BACKGROUND: Cissampelos pareira (Menispermaceae) is used in folk Indian system of alternative medicine, for its analgesic, antipyretic, diuretic, antilithic, and emmenagogue properties. OBJECTIVE: To evaluate Cissampelos pareira (C. pareira) for in vitro cytotoxicity and in vivo antitumor activity against Dalton's Lymphoma Ascites (DLA) cells in Swiss mice. MATERIALS AND METHODS: Cissampelos pareira was successively extracted using different solvents. In vitro cytotoxicity was assessed by the MTT assay. An in vivo study was carried out in methanol extract. Twenty-four hours after intraperitoneal inoculation of the DLA cells in mice, the methanol extract of C. pariera (MECP) was administered at 200 and 400 mg/kg body weight for 14 consecutive days. On day 14, six mice were sacrificed and the rest were kept alive for assessment of increase in life-span. The antitumor effect was assessed by evaluating the packed cell volume, viable tumor cell count, increase in body weight, and increase in life-span. The hematological and serum biochemical parameters and anti-oxidant properties were assessed by estimating the superoxide dismutase (SOD), catalase (CAT), and lipid peroxidation. RESULTS: Methanol Extract of Cissampelos pariera (MECP) showed a potent cytotoxic activity, with an IC50 value of 95.5 µg/ml and a significant (P < 0.001) decrease in packed cell volume, viable cell count, and an increased lifespan (54 and 72%). The hematological and serum biochemical profiles were restored to normal levels in MECP-treated mice. The MECP-treated group significantly (P < 0.001) decreased SOD, lipid peroxidation, and CAT to normal. CONCLUSION: This study demonstrated that C. pariera exhibited significant in vitro and in vivo anti-tumor activities and that it was reasonably imputable to its increasing endogenous mechanism of antioxidant property.

Hydnocarpus: an ethnopharmacological, phytochemical and pharmacological review.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Hydnocarpus (Flacourtiaceae) includes forty species that are spread across the globe. In the Indian System of Medicine, Hydnocarpus pentandrus (Buch.-Ham.) Oken. is primarily used for treating leprosy and other skin disorders. It is known as "Chaulmoogra" and is also used to treat other indications including constipation, inflammation, blood disorders, and worm infestations. Various species of Hydnocarpus are also used in traditional medicine in China, Thailand, Malaysia, and Myanmar for several skin disorders. To assess the therapeutic potential of species from the Hydnocarpus genus and to determine future avenues for research. METHODS: All relevant scientific literature published up to the end of December 2013 was retrieved via a library and electronic search (SciFinder, PubMed, ScienceDirect, and Google Scholar). Manual searches of traditional books like to ancient classics, including Vaidya Yoga Ratnavali, Siddha Materia Medica, and contemporary references including The Ayurvedic Pharmacopoeia of India and The Ayurveda Formulary, were also performed. RESULTS: Seed oil from species of the Hydnocarpus genus is used for medicinal purposes, predominantly for various skin disorders. This oil is reported to contain a characteristic class of compounds known as cyclopentenyl fatty acids. Furthermore, seeds of this genus are reported to contain triglycerides of fatty acids, sterols, flavonoids, and flavonolignans. Hydnocarpin, a flavonolignan, is reported to potentiate antimicrobial and anticancer activity. The extracts and compounds isolated from this plant show a wide spectrum of pharmacological properties, including antibacterial, antileprotic, antitubercular, antipsoriatic, antirheumatic, hypolipidemic, antidiabetic, anticancer, anti-inflammatory, and antioxidant activities. The antileprotic activity is postulated to be due to the cyclopentenyl fatty acids present in the seed oil. CONCLUSION: Flavonolignans have an interesting chemical motif, and hydnocarpin and its congeners should be investigated for their activities and the mechanism underlying these activities. Multi-drug-resistant microbes are on the increase, and the possible inhibitory effect of these compounds when used with current antimicrobials should also be evaluated. Furthermore, unique cyclopentenyl fatty acids should also be investigated to understand the exact mechanism of action underlying antileprotic activity. Additional in depth phytochemical investigations of seed oil and extracts are required to tap the true potential of species from the Hydnocarpus genus.

In vitro cytotoxic activity of menispermaceae plants against HeLa cell line.

BACKGROUND: Menispermaceae, a family of flowering plants, is a medium-sized family of 70 genera totaling 420 extant species, mostly of climbing plants. It has various medicinal properties, which are used in the Ayurvedic system of medicine. Plants belonging to this family are rich in alkaloids, especially bisbenzylisoquinoline type. The hypothesis of this study is that the bisbenzylisoquinoline alkaloids present in the selected plants may exhibit in vitro cytotoxic property. AIM: The present study is aimed at estimating the total alkaloidal content of methanolic extract of Cocculus hirsutus and Cissampelos pareira and evaluating the in vitro cytotoxic activity of both the extracts on the HeLa cell line. SETTINGS AND DESIGN: Methanolic extracts of both the plants in the concentrations of 500, 250, 125, 62.5, and 31.25 µg/ml were assessed for its cytotoxic activity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MATERIALS AND METHODS: Total alkaloidal content was studied for both the plants using ultraviolet-visible spectroscopy method. Methanol extracts of both the plants were tested for its inhibitory effect on HeLa cell line. Cytotoxicity of the plant extracts was evaluated by MTT assay. Nonlinear regression graph was plotted between % cell inhibition and Log10 concentration, and IC50 was determined using GraphPad Prism software. RESULTS: Preliminary phytochemical studies confirm the presence of alkaloids in both the plants. The total alkaloids present in C. hirsutus and C. pareira were found to be 0.252%w/w and 0.1656%w/w respectively. The IC50 values of C. hirsutus and C. pareria were found to be 111 µg/ml and 129.3 µg/ml respectively. CONCLUSION: From this study, it is observed that C. hirsutus and C. pareira have in vitro cytotoxic activity against HeLa cell line.

Evaluation of the antipsoriatic activity of Aloe vera leaf extract using a mouse tail model of psoriasis.

Aloe vera gel is used traditionally for the treatment of skin diseases, including psoriasis. An ethanolic extract of the gel was assessed for antipsoriatic activity using a mouse tail model of psoriasis. The extract produced a significant differentiation in the epidermis, as seen from its degree of orthokeratosis (85.07 ± 3.36%) when compared with the negative control (17.30 ± 4.09%). This was equivalent to the effect of the standard positive control, tazarotene (0.1%) gel, which showed a 90.03 ± 2.00% degree of orthokeratosis. The ethanolic extract of Aloe vera leaf gel also produced a significant increase in relative epidermal thickness when compared with the control group, whereas the standard tazarotene showed no change. Taken together, the extract showed an overall antipsoriatic activity of 81.95%, compared with 87.94 for tazarotene, in the mouse tail model for psoriasis.

Relationship between Antioxidant Properties and Chemical Composition of Abutilon Indicum Linn.

Aim of this paper is to find out the relationship between antioxidant activity of Abutilon indicum Linn and their phytochemical composition especially phenols and flavonols. Successive extractions were carried out for the Abutilon indicum plant with petroleum ether, chloroform, ethyl acetate, n-butanol, ethanol and water. All these extracts were evaluated for their antioxidant activities. Their antioxidant activities were correlated with their total phenol and flavonol content present in the plant. Ethyl acetate showed maximum free radical scavenging activity. IC(50) value for various antioxidant methods for all extract showed no significance with total antioxidant capacity except IC(50) value of LPO (r(2) = 0.7273). Correlation between total antioxidant capacity and total phenolic content was not significant with r(2) = 0.2554, P<0.3065. Total antioxidant capacity and total flavonol content showed similar correlation with r(2) = 0.2554, P<0.0962.

Antidiabetic activity of ethanolic extract of tubers of Dioscorea alata in alloxan induced diabetic rats.

OBJECTIVE: To evaluate the antidiabetic activity of ethanolic extract of Dioscorea alata in glucose loaded and alloxan induced diabetic rats. MATERIALS AND METHODS: The authenticated tubers of D. alata (DA) (JSSCPDP/2008/157) were collected from Dharmapuri, Tamil Nadu. The ethanol extract was tested for hypoglycemic activity in normal rats. In oral glucose tolerance test, glucose (3 g/kg, p.o.) was administered to non diabetic control, metformin (250 mg/kg, p.o.) and DA extract (100 and 200 mg/kg, p.o.) to treat treated rats. Diabetes mellitus was induced by alloxan monohydrate (120 mg/kg, i.p.) in physiological saline after overnight fasting for 18 hours. DA extract (100 and 200 mg/kg, p.o.) and standard drug metformin (250 mg/kg, p.o.) were administered to diabetic rats for 21 days. Fasting blood glucose level and changes in body weight were measured on days 0, 7, 14, and 21. At the end of 21(st) day, serum lipid profile, total protein, albumin, and creatinine were assessed. RESULTS: In glucose loaded normal rats, the treatment with the extract of DA had shown a highly significant reduction (P < 0.001) in blood glucose levels at the doses of 100 and 200 mg/kg, respectively. The extract did not produce hypoglycemic activity at both the dose levels in normal, fasted rats. In alloxan induced diabetic rats, the body weight of the DA extract treated animals had shown a significant increase (P < 0.001) after 21 days treatment. The blood glucose level was reduced significantly by 47.48% and 52.09% after 21 days treatment at dose levels 100 and 200 mg/kg, respectively. Serum lipid levels, total protein, albumin, and creatinine were reversed toward near normal in treated rats as compared to diabetic control. CONCLUSION: The results indicate that ethanol extract of DA tubers possesses significant antidiabetic activity.