Comparative assessment of the antioxidant activity and free radical scavenging potential of different parts of Nerium indicum

Context: Reactive oxygen species (ROS) cause damage to cellular components. Antioxidant compounds scavenge or neutralize the ROS and thus have significant role in human health. Aims: The present study 70% methanol extracts of Nerium indicum leaf, stem and root were evaluated for in vitro total antioxidant, radical scavenging activity along with phenolic and flavonoid contents. Methods and Material: The extracts were examined for the scavenging activity of hydroxyl radical, nitric oxide, singlet oxygen, hypochlorous acid, superoxide, peroxynitrite, hydrogen peroxide. The extracts were also tested for their potential as an iron chelating agent, inhibition of lipid peroxidation and total reducing potential. Results: The present study indicates that the total antioxidant, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical and singlet oxygen scavenging potential is in the order of stem>root>leaf. The hydroxyl radical scavenging, hydrogen peroxide scavenging and hypochlorous acid scavenging activity is in the order leaf>stem>root, whereas superoxide scavenging and lipid peroxidation inhibition assay is root>leaf>stem. Miscellaneous results were obtained in the scavenging of other radicals by the extracts, viz., leaf>root>stem for peroxynitrite and iron chelation activity, root>stem>leaf for reducing power and stem>leaf>root for nitric oxide inhibition. The phenolic and flavonoid content is in the following order root>stem>leaf and leaf>stem>root respectively. Conclusions: The present study revealed that the leaf, stem and root extracts of N. indicum are effective free radical scavenger and might be used as a natural source of potent antioxidant

Comparative assessment of the antioxidant activity and free radical scavenging potential of different parts of Nerium indicum

Context: Reactive oxygen species (ROS) cause damage to cellular components. Antioxidant compounds scavenge or neutralize the ROS and thus have significant role in human health. Aims: The present study 70% methanol extracts of Nerium indicum leaf, stem and root were evaluated for in vitro total antioxidant, radical scavenging activity along with phenolic and flavonoid contents. Methods and Material: The extracts were examined for the scavenging activity of hydroxyl radical, nitric oxide, singlet oxygen, hypochlorous acid, superoxide, peroxynitrite, hydrogen peroxide. The extracts were also tested for their potential as an iron chelating agent, inhibition of lipid peroxidation and total reducing potential. Results: The present study indicates that the total antioxidant, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical and singlet oxygen scavenging potential is in the order of stem>root>leaf. The hydroxyl radical scavenging, hydrogen peroxide scavenging and hypochlorous acid scavenging activity is in the order leaf>stem>root, whereas superoxide scavenging and lipid peroxidation inhibition assay is root>leaf>stem. Miscellaneous results were obtained in the scavenging of other radicals by the extracts, viz., leaf>root>stem for peroxynitrite and iron chelation activity, root>stem>leaf for reducing power and stem>leaf>root for nitric oxide inhibition. The phenolic and flavonoid content is in the following order root>stem>leaf and leaf>stem>root respectively. Conclusions: The present study revealed that the leaf, stem and root extracts of N. indicum are effective free radical scavenger and might be used as a natural source of potent antioxidant

QUANTIFICATION AND CORRELATION OF THE BIOACTIVE PHYTOCHEMICALS OF CROTON BONPLANDIANUM LEAVES OF SUB-HIMALAYAN REGION OF WEST BENGAL

Objective: Leaves of various herbs are rich in phytochemicals which may provide protection from various diseases. Therefore, the objective of the present study was preliminary screening of the phytochemicals like tannin, phlobatannin, cholesterol, glycoside, terpinoids, phenolics, flavonoid, steroid, anthraquinone, saponin, carbohydrate, alkaloid and protein in leaf of Croton bonplandianum Baill. and quantify some of these phytochemical. Method: Standardized biochemical and UV-Vis spectrophotometric methods were followed to analyze the phytochemical status of the leaves. Principal component analysis and correlation matrix on the basis of the quantity of the bioactive phytochemicals were performed in order to elucidate the interrelation between the various phytochemicals Result: Quite a high percentage of alkaloid (59.60 ± 4.79 g/100g), saponin (17.35 ± 1.35 g/100g), phenolic content (75.39 ± 3.19 mg/g), protein (55.04 ± 2.09 mg/g), lipid (37.53 ± 2.43 mg/g), tannin (26.18 ± 2.63 mg/100g), thiamine (26.18± 2.36 mg/100g) and very satisfactory quantity of riboflavin or vitamin B2 (0.55 ± 0.03 mg/100g), ascorbic acid (0.71 ± 0.05 mg/100g)  has been detected in the leaves of this plant. It is fascinating to note that the phenol with lipid and the riboflavin content have displayed almost linear positive correlation with correlation coefficient of 0.999. Conclusion: It can be concluded from the present study that the leaf of C. bonplandianum possesses rich in various phytochemicals like alkaloid, total phenol, saponin, flavonoid, protein and tannin. These phytochemicals possess various bioactive properties and may be used as external therapeutic supplement. This study may lead to a new dimension regarding the medicinal value of C. bonplandianum

COMPARATIVE SEQUENCE ANALYSIS OF TLR2 TLR4 AND TLR9 GENES AMONG SELECTED VERTEBRATES-A META-ANALYSIS

Objective: Toll-like receptors are the pattern recognition receptors that recognize a diverse set of conserved pathogens. The receptors are also constantly under selection pressure because of the host antigen modifications. The present study focuses on how selection and mutation have modified the TLRs throughout the evolution in selected groups.Methods: We have selected the sequences of TLR2, 4 and 9 among Hominid group, Homo sapiens, Bubalus bubalis and Danio rerio in our analysis and analyzed different parameters like relative synonymous codon usage (RSCU), sequence divergence, amino acid composition and estimated evolutionary selection forces using Tajima's test.Results: The phylogenetic assessment proved that positive selection influences TLR2 and TLR4, but neutral selection/balancing selection occurred in TLR9 which concluded from the Tajima's test. Synonymous codon usage described the selection of leucine and arginine in all the sequences which describe the structural similarities of TLRs. Values of nucleotide pairs and disparity index proved the close relationship of Hominid and Human between TLR2 and TLR4 and TLR9 where the distant relationship was found with Danio. It can be hypothesized that some of the codons may be best selected for binding with the antigens and it was selected in the genome and some were eliminated due to selection pressure.Conclusion: The present study aimed to substantiate the closeness of TLR2 and TLR4 due to their functional similarity but distant with TLR9 because of the different antigens they recognized in the endosome

Role of toll like receptors in bacterial and viral diseases – A systemic approach

Background: Toll like receptors are key-receptors of the innate immune system, but their role against bacterial and viral infections are yet to be understood.Aim: The present study is aimed to investigate the diversity and frequency distribution of 10 TLR genes among typhoid fever and HIV+ patients. In this study, 44 samples were taken from typhoid patients and 55 samples from HIV+ patients.Patients and methods: Widal test positive samples (>1:80) in case of typhoid and the percentage of CD4+ count in case of HIV+ patient were considered for the PCR-SSP analysis.Results: We found that the frequencies of TLR1 and TLR6 were highest in typhoid patients, whereas the frequencies of TLR8 and TLR9 displayed higher among HIV+ patients. Chi-square values were significant for TLR8 and TLR10 in the case of typhoid patients, whereas in HIV patients significant values were considered for TLR2, TLR4, TLR8 and TLR9 respectively. The odds ratio calculated highest for TLR1 and TLR6 among typhoid patients. TLR4 and TLR9 calculated were highest odd for HIV+ patients. A door line association of TLRs with the disease was found when the relative risk was calculated for TLR2 (1.72), TLR3 (1.21) and TLR10 (1.98) in bacterial infection, whereas in case of viral infection relative risk was calculated for TLR4 (1.62), TLR8 (1.18) and in TLR9 (1.16).Conclusion: This study reports the frequency distribution and association of human TLR genes with the bacterial and viral infection in the North Bengal region of India for the first time. It also signified the gene- disease- environment association study in case of infectious diseases and also the risk factors of bacterial and viral infections in this region. It also depicts the role of TLRs in the recognition of the pathogens

ANTI-INFLAMMATORY AND PROTECTIVE PROPERTIES OF ALOE VERA LEAF CRUDE GEL IN CARRAGEENAN INDUCED ACUTE INFLAMMATORY RAT MODELS

Objectives: Current clinical treatment regimes for inflammatory diseases have different drawbacks including side effects of the drugs and the high cost of long term treatment. In the last few decades different promising herbal medicines have been explored for their anti-inflammatory and anti-rheumatic effects, but conclusive evidences are not available in the case of crude Aloe vera gel for its anti-inflammatory effects. The objective of the study was to document the protective and curative roles of orally administered and peritoneally injected crude wild Aloe vera gel in carrageenan-induced inflammation in a rat model. Methods: Inflammation was induced by injecting 1% carrageenan in the left hind paw of Wistar albino rat. Crude, unprocessed Aloe vera gel was peritoneally injected and orally fed to experimental and control rat groups to investigate its effect on paw joint edema by measuring the paw circumference with vernier caliper. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell viability assay was performed to investigate the cytotoxic effect of the gel. Results: Paw edema was brought to near normal levels in the experimental groups after the treatment with crude Aloe vera gel. Orally fed gel showed no cytotoxicity on macrophages and spleenocytes. Protective property of crude Aloe gel was also evident in both the experiments. Conclusion: Aloe vera crude gel has both protective and curative properties against inflammation

Multifaceted role of matrix metalloproteinases (MMPs)

Matrix metalloproteinases (MMPs), a large family of calcium-dependent zinc-containing endopeptidases, are involved in the tissue remodeling and degradation of the extracellular matrix. MMPs are widely distributed in the brain and regulate various processes including microglial activation, inflammation, dopaminergic apoptosis, blood-brain barrier disruption, and modulation of α-synuclein pathology. High expression of MMPs is well documented in various neurological disorders including Parkinson\u27s disease (PD), Alzheimer\u27s disease (AD), Japanese encephalitis (JE), and Glaucoma. Although potentially critical, the role of MMPs in neuronal disorders is under-investigated. The present review summarizes the role of MMPs in neurodegeneration with a particular emphasis on PD, AD, JE, and Glaucoma

A participação de PMEs portuguesas em alianças de I&D: programa CRAFT

A formação de alianças de base tecnológica conheceu um incremento notável nas décadas de 1980 e 1990, representando actualmente uma estratégia empresarial importante de acesso ao conhecimento tecnológico, fortemente incentivada pela generalidade dos países da OCDE. A literatura sobre alianças realça as enormes vantagens mútuas que podem resultar da cooperação tecnológica bem sucedida. Raramente, porém, são abordados empiricamente os problemas específicos da participação de PMEs em alianças de I&D, e menos ainda quando essas empresas pertencem a sectores tradicionais e têm limitações evidentes para participar em alianças de I&D. Este trabalho aborda esta problemática no quadro da participação de PMEs portuguesas no programa europeu CRAFT (1994-98). Os resultados indicam que o empenhamento dos parceiros, os aspectos culturais e a falta de recursos internos representam os aspectos mais negativos da cooperação. Isto é, em grande medida, consequência das condições iniciais que estiveram na génese das alianças mas a estrutura das alianças também é importante. As PMEs portuguesas ficaram, em geral, satisfeitas com os benefícios obtidos mas o sucesso técnico da aliança não garante que as empresas tenham condições para materializar os benefícios potenciais gerados no âmbito da aliança