Modulation of Insulin Resistance by Silybum marianum Leaves, and its Synergistic Efficacy with Gymnema sylvestre, Momordica charantia, Trigonella-foenum graecum Against Protein Tyrosine Phosphatase 1B.

Prolonged insulin resistance is considered one of the reasons for Type 2 Diabetes Mellitus. Upregulation of Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signalling, has been well studied as a key regulator in prognosis to insulin resistance. It has been widely studied as a desirable molecular therapeutic target. The study aimed to evaluate the efficacy of leaf extract of the medicinal plants Silybum marianum on the inhibition of PTP1B activity. It also explored the synergistic effect with extracts of Gymnema sylvestre (leaves), Momordica charantia (seeds), and Trigonella foenum graecum (seeds). The S. marianum leaves showed dose-dependent inhibition of PTP1B ranging from 9.48-47.95% (25-1000 µg mL-1). Assay with individual plant extracts showed comparatively lesser inhibition of PTP1B as compared to metformin as a control (38% inhibition). However, a synergistic effect showed nearly 45% PTP1B inhibition (higher than metformin) after the assay was done with selected four plant extracts in combination. The effect of leaf extracts of S. marianum was studied for glucose uptake efficiency in yeast cell lines which was found to be increased by 23% as compared to the control (without extract). Metformin improves glucose upake by yeast cells by ~15-31%. GC-MS analysis revealed 23 phytochemicals, some of which possessed anti-diabetic properties. A dose-dependent increase in antioxidant activity of S. marianum leaves extracts was observed (40-53%). The findings of the study highlighted the presence of various phytochemicals in leaves extracts that are effective against PTP1B inhibition and may help in reinvigorating drug development.

Cancer treatment with nano-diamonds.

Diamond nano-particles find new and far-reaching applications in modern biomedical science and biotechnologies. Due to its excellent biocompatibility, nano-diamonds serve as versatile platforms that can be embedded within polymer-based microfilm devices. Nano-diamonds are complexed with a chemotherapeutic that enables sustained/slow release of the drug for a minimum of one month, with a significant amount of drug in reserve. This opens up the potential for highly localized drug release as a complementary and potent form of treatment with systemic injection towards the reduction of continuous dosing, and as such, attenuation of the often powerful side effects of chemotherapy. Nano-diamonds are quite economical, enabling the broad impact of these devices towards a spectrum of physiological disorders e.g. serving as a local chemotherapeutic patch, or as a pericardial device to suppress inflammation after open heart surgery. Nano-diamond patch could be used to treat a localized region where residual cancer cells might remain after a tumor is removed. Nano-diamonds can be used to explore a broad range of therapeutic classes, including additional small molecules, proteins, therapeutic antibodies, RNAi.

Nutraceuticals for geriatrics.

Geriatrics is a medical practice that addresses the complex needs of older patients and emphasizes maintaining functional independence even in the presence of chronic disease. Treatment of geriatric patients requires a different strategy and is very complex. Geriatric medicines aim to promote health by preventing and treating diseases and disabilities in older adults. Development of effective dietary interventions for promoting healthy aging is an active but challenging area of research because aging is associated with an increased risk of chronic disease, disability, and death. Aging populations are a global phenomenon. The most widespread conditions affecting older people are hypertension, congestive heart failure, dementia, osteoporosis, breathing problems, cataract, and diabetes to name a few. Decreased immunity is also partially responsible for the increased morbidity and mortality resulting from infectious agents in the elderly. Nutritional status is one of the chief variables that explains differences in both the incidence and pathology of infection. Elderly people are at increased risk for micronutrient deficiencies due to a variety of factors including social, physical, economic, and emotional obstacles to eating. Thus there is an urgent need to shift priorities to increase our attention on ways to prevent chronic illnesses associated with aging. Individually, people must put increased efforts into establishing healthy lifestyle practices, including consuming a more healthful diet. The present review thus focuses on the phytochemicals of nutraceutical importance for the geriatric population.

Assessment of phytochemical composition and antioxidant potential in some indigenous chilli genotypes from North East India.

Twenty five chilli genotypes from North East region of India evaluated showed variation for capsaicin from 0.27% (CHF-CA-1) to 3.03% (CHF-CA-21), oleoresin content from 2.49% (CHF-CA-5) to 9.26% (CHF-CA-18) with high to moderate ascorbic acid. Total phenolics ranged from 5.1 (CHF-CA-8) to 26.8 (CHF-CA-23) mg GAE/g and total carotenoids from 0.09 (CHF-CA-16) to 7.72 (CHF-CA-17) mg/g dry weight. The antioxidant activity varied from 15.3% (CHF-CA-4) to 60.7% (CHF-CA-21). Free radical scavenging activity using DPPH assay showed low IC50 ranging from 0.021 to 0.041 mg/mg, low EC50 from 0.92 to 1.78 mg/mg DPPH, high ARP values (56.17-109.52) in CHF-CA-6, CHF-CA-7, CHF-CA-17, CHF-CA-21, CHF-CA-22 and CHF-CA-23 genotypes. The reducing power ranged from 0.92 to 4.10 ASE/ml and specific phenolic composition showed presence of gallic acid with other hydroxycinnamic acid. Among the flavonoids, presence of catechin was maximum followed by quercetin and rutin.

Phytonutrients as therapeutic agents.

Nutrients present in various foods plays an important role in maintaining the normal functions of the human body. The major nutrients present in foods include carbohydrates, proteins, lipids, vitamins, and minerals. Besides these, there are some bioactive food components known as "phytonutrients" that play an important role in human health. They have tremendous impact on the health care system and may provide medical health benefits including the prevention and/or treatment of disease and various physiological disorders. Phytonutrients play a positive role by maintaining and modulating immune function to prevent specific diseases. Being natural products, they hold a great promise in clinical therapy as they possess no side effects that are usually associated with chemotherapy or radiotherapy. They are also comparatively cheap and thus significantly reduce health care cost. Phytonutrients are the plant nutrients with specific biological activities that support human health. Some of the important bioactive phytonutrients include polyphenols, terpenoids, resveratrol, flavonoids, isoflavonoids, carotenoids, limonoids, glucosinolates, phytoestrogens, phytosterols, anthocyanins, ω-3 fatty acids, and probiotics. They play specific pharmacological effects in human health such as anti-microbial, anti-oxidants, anti-inflammatory, antiallergic, anti-spasmodic, anti-cancer, anti-aging, hepatoprotective, hypolipidemic, neuroprotective, hypotensive, diabetes, osteoporosis, CNS stimulant, analgesic, protection from UVB-induced carcinogenesis, immuno-modulator, and carminative. This mini-review attempts to summarize the major important types of phytonutrients and their role in promoting human health and as therapeutic agents along with the current market trend and commercialization.

Bioremediation: a genuine technology to remediate radionuclides from the environment.

Radionuclides in the environment are a major human and environmental health concern. Like the Chernobyl disaster of 1986, the Fukushima Daiichi nuclear disaster in 2011 is once again causing damage to the environment: a large quantity of radioactive waste is being generated and dumped into the environment, and if the general population is exposed to it, may cause serious life-threatening disorders. Bioremediation has been viewed as the ecologically responsible alternative to environmentally destructive physical remediation. Microorganisms carry endogenous genetic, biochemical and physiological properties that make them ideal agents for pollutant remediation in soil and groundwater. Attempts have been made to develop native or genetically engineered (GE) microbes for the remediation of environmental contaminants including radionuclides. Microorganism-mediated bioremediation can affect the solubility, bioavailability and mobility of radionuclides. Therefore, we aim to unveil the microbial-mediated mechanisms for biotransformation of radionuclides under various environmental conditions as developing strategies for waste management of radionuclides. A discussion follows of '-omics'-integrated genomics and proteomics technologies, which can be used to trace the genes and proteins of interest in a given microorganism towards a cell-free bioremediation strategy.

Glucosinolates: the phytochemicals of nutraceutical importance.

Glucosinolates (thioglucoside-N-hydroxysulphates) constitute a homogeneous class of naturally occurring thiosaccharidic compounds mainly found in the botanical order Brassicales. They can be hydrolyzed by myrosinase to produce D-glucose and various other degradation products like isothiocyanates (ITCs)-depending on the aglycon part. The exact function of glucosinolates (GLSs) in the plant is unclear, however their potent odour and taste suggests a role in herbivore and microbial defense. They are known for their fungicidal, bacteriocidal, nematocidal and allelopathic properties and have recently attracted intense research interest because of their cancer chemo-protective attributes. Iso-thiocyanates, one of the hydrolyzed products, show best anti-carcinogenic activity.

Emergence of antibiotic-resistant extremophiles (AREs).

Excessive use of antibiotics in recent years has produced bacteria that are resistant to a wide array of antibiotics. Several genetic and non-genetic elements allow microorganisms to adapt and thrive under harsh environmental conditions such as lethal doses of antibiotics. We attempt to classify these microorganisms as antibiotic-resistant extremophiles (AREs). AREs develop strategies to gain greater resistance to antibiotics via accumulation of multiple genes or plasmids that harbor genes for multiple drug resistance (MDR). In addition to their altered expression of multiple genes, AREs also survive by producing enzymes such as penicillinase that inactivate antibiotics. It is of interest to identify the underlying molecular mechanisms by which the AREs are able to survive in the presence of wide arrays of high-dosage antibiotics. Technologically, "omics"-based approaches such as genomics have revealed a wide array of genes differentially expressed in AREs. Proteomics studies with 2DE, MALDI-TOF, and MS/MS have identified specific proteins, enzymes, and pumps that function in the adaptation mechanisms of AREs. This article discusses the molecular mechanisms by which microorganisms develop into AREs and how "omics" approaches can identify the genetic elements of these adaptation mechanisms. These objectives will assist the development of strategies and potential therapeutics to treat outbreaks of pathogenic microorganisms in the future.

Development of an HPLC method for determination of pentachloronitrobenzene, hexachlorobenzene and their possible metabolites.

BACKGROUND: Pentachloronitrobenzene (PCNB) and hexachlorobenzene (HCB) are highly toxic and widespread in every environmental compartment. Some of metabolic products such as amino/nitro containing chlorinated aromatic compounds can be determined by gas chromatography coupled with electron capture detector (GC-ECD). However, it is difficult to identify some of chlorophenolic and chloroquinolic intermediates produced from PCNB and HCB by the above mentioned technique. Therefore, for analysis of these compounds and their metabolites, we have developed a high performance liquid chromatography (HPLC) based method. RESULTS: The extraction of PCNB and HCB from soil and minimal salt medium was carried out with ethyl acetate and hexane respectively with good recoveries (98% for PCNB and 97% for HCB). The validation of the proposed extraction and HPLC method was done by analysis of PCNB and HCB biodegradation and their metabolites identification from anaerobic enriched soil samples. CONCLUSION: A rapid, sensitive and simple HPLC based analytical method was developed for the analysis of PCNB, HCB and their possible intermediates.

Novel pathway for the degradation of 2-chloro-4-nitrobenzoic acid by Acinetobacter sp. strain RKJ12.

The organism Acinetobacter sp. RKJ12 is capable of utilizing 2-chloro-4-nitrobenzoic acid (2C4NBA) as a sole source of carbon, nitrogen, and energy. In the degradation of 2C4NBA by strain RKJ12, various metabolites were isolated and identified by a combination of chromatographic, spectroscopic, and enzymatic activities, revealing a novel assimilation pathway involving both oxidative and reductive catabolic mechanisms. The metabolism of 2C4NBA was initiated by oxidative ortho dehalogenation, leading to the formation of 2-hydroxy-4-nitrobenzoic acid (2H4NBA), which subsequently was metabolized into 2,4-dihydroxybenzoic acid (2,4-DHBA) by a mono-oxygenase with the concomitant release of chloride and nitrite ions. Stoichiometric analysis indicated the consumption of 1 mol O(2) per conversion of 2C4NBA to 2,4-DHBA, ruling out the possibility of two oxidative reactions. Experiments with labeled H(2)(18)O and (18)O(2) indicated the involvement of mono-oxygenase-catalyzed initial hydrolytic dechlorination and oxidative denitration mechanisms. The further degradation of 2,4-DHBA then proceeds via reductive dehydroxylation involving the formation of salicylic acid. In the lower pathway, the organism transformed salicylic acid into catechol, which was mineralized by the ortho ring cleavage catechol-1,2-dioxygenase to cis, cis-muconic acid, ultimately forming tricarboxylic acid cycle intermediates. Furthermore, the studies carried out on a 2C4NBA(-) derivative and a 2C4NBA(+) transconjugant demonstrated that the catabolic genes for the 2C4NBA degradation pathway possibly reside on the ∼55-kb transmissible plasmid present in RKJ12.

Reductive dehalogenation mediated initiation of aerobic degradation of 2-chloro-4-nitrophenol (2C4NP) by Burkholderia sp. strain SJ98.

Burkholderia sp. strain SJ98 (DSM 23195) was previously isolated and characterized for degradation and co-metabolic transformation of a number nitroaromatic compounds. In the present study, we evaluated its metabolic activity on chlorinated nitroaromatic compounds (CNACs). Results obtained during this study revealed that strain SJ98 can degrade 2-chloro-4-nitrophenol (2C4NP) and utilize it as sole source of carbon, nitrogen, and energy under aerobic conditions. The cells of strain SJ98 removed 2C4NP from the growth medium with sequential release of nearly stoichiometric amounts of chloride and nitrite in culture supernatant. Under aerobic degradation conditions, 2C4NP was transformed into the first intermediate that was identified as p-nitrophenol by high-performance liquid chromatography, LCMS-TOF, and GC-MS analyses. This transformation clearly establishes that the degradation of 2C4NP by strain SJ98 is initiated by "reductive dehalogenation"; an initiation mechanism that has not been previously reported for microbial degradation of CNAC under aerobic conditions.

Antioxidant and free radical scavenging activities of some fruits.

Phenols, a major group of antioxidant phytochemicals, have profound importance due to their biological and free radical scavenging activities. To identify their potential sources extracts of some fruits and their different parts were studied for total phenolic contents (TPC), antioxidant (AOA) and free radical scavenging activities (FRSA). The amount of TPC varied from 10.5 (Carissa carandus, fruit peel) to 343.2 mg/g (Caesalpinia Mexicana, fruits) and AOA from 20.3% (Musa paradisiacal, fruits) to 96.7% (Caesalpinia Mexicana, fruits). Fruits of Caesalpinia Mexicana, Acacia auriculiformis, fruit pericarp green fibres of Cocus nucifera, and fruits of Emblica officinalis were found to have high TPC (73.1-343.2 mg/g) and high AOA (68.5-96.7%). Promising fruits were studied for their FRSA and reducing power (RP) measured by DPPH assay where the fruits of Caesalpinia mexicana, fruit pericarp fibres of Cocus nucifera, fruits of Emblica officinalis showed very low IC50 ranging from 0.009 to 0.016 mg/ml, EC50 from 0.39 to 0.70 mg/mg DPPH and reasonably high values (142.1-256.3) of anti radical power (ARP), indicating their strong FRSA and reducing power (RP) as evident by their low ASE/ml values (0.42-1.08). They also showed better inhibition of lipid peroxidation measured by using ferric thiocyanate assay and by using egg yolk compared to the reference standard quercetin. The ferrous and ferric ion chelating capacity of the promising fruits and their underutilized parts in terms of IC50 varied from 0.12 (Emblica officinalis, fruits) to 2.44 mg/ml (Mangifera indica, Seed kernel) and 0.22 (Caesalpinia Mexicana, fruits) to 2.59 mg/ml (Litchi chinensis, fruit peel) respectively. Fruit pulp, peel and seeds of Litchi chinensis with reasonable amount of phenols (48.3, 43.9, 50.1 mg/ml) showed low ARP (23.5, 38.3, 33.8) and ASE/ml (3.13, 2.18, 2.62) respectively in contrast to Aegle marmelos with comparatively lower phenols (35.1 mg/g) exhibited good ARP (57.4) and RP (1.67 ASE/ml). Extracts (20 µg/ml) of fruits of Acacia auriculiformis, Caesalpinia Mexicana, Emblica officinalis, fruit pericarp fibres of Cocus nucifera, were found effective in protecting plasmid DNA nicking induced by Fenton's reagent generated hydroxyl radicals. They were further assayed for their specific phenolic composition through HPLC and MS/MS where the amount of caffeic acid varied from 48.5 to 2231 µg/g, chlorogenic acid 63.8 to 912.1 µg/g, ellagic acid 46.4 to 1429.1 µg/g, ferulic acid 36.7 to 762.9 µg/g, gallic acid 181.6 to 2831.6 µg/g, protocatechuic acid 41.7 to 322.8 µg/g, and quercetin 44.6 to 367.6 µg/g.

A process optimization for bio-catalytic production of substituted catechols (3-nitrocatechol and 3-methylcatechol.

BACKGROUND: Substituted catechols are important precursors for large-scale synthesis of pharmaceuticals and other industrial products. Most of the reported chemical synthesis methods are expensive and insufficient at industrial level. However, biological processes for production of substituted catechols could be highly selective and suitable for industrial purposes. RESULTS: We have optimized a process for bio-catalytic production of 3-substituted catechols viz. 3-nitrocatechol (3-NC) and 3-methylcatechol (3-MC) at pilot scale. Amongst the screened strains, two strains viz. Pseudomonas putida strain (F1) and recombinant Escherichia coli expression clone (pDTG602) harboring first two genes of toluene degradation pathway were found to accumulate 3-NC and 3-MC respectively. Various parameters such as amount of nutrients, pH, temperature, substrate concentration, aeration, inoculums size, culture volume, toxicity of substrate and product, down stream extraction, single step and two-step biotransformation were optimized at laboratory scale to obtain high yields of 3-substituted catechols. Subsequently, pilot scale studies were performed in 2.5 liter bioreactor. The rate of product accumulation at pilot scale significantly increased up to approximately 90-95% with time and high yields of 3-NC (10 mM) and 3-MC (12 mM) were obtained. CONCLUSION: The biocatalytic production of 3-substituted catechols viz. 3-NC and 3-MC depend on some crucial parameters to obtain maximum yields of the product at pilot scale. The process optimized for production of 3-substituted catechols by using the organisms P. putida (F1) and recombinant E. coli expression clone (pDTG602) may be useful for industrial application.

Physiological adaptations and tolerance towards higher concentration of selenite (Se(+4)) in Enterobacter sp. AR-4, Bacillus sp. AR-6 and Delftia tsuruhatensis AR-7.

Environmental contamination with selenium is a major health concern. A few bacterial strains have been isolated that can transform toxic selenite to non-toxic elemental selenium only at low concentrations (0.001-150 mM) in recent past. We have previously reported isolation and characterization of few selenite-tolerant bacterial strains. These strains were found to be resistant to selenite at (300-600 mM) concentrations. In the present study we have characterized some physiological adaptations of strains Enterobacter sp. AR-4, Bacillus sp. AR-6 and Delftia tsuruhatensis AR-7 during exposure to higher concentration of selenite under aerobic and anaerobic environments. Adaptive responses are largely associated with alteration of cell morphology and change in total cellular fatty acid composition. Interestingly, electron microscopy studies revealed substantial decrease in cell size and intracellular deposition of Se(0) crystals when reduction is carried out under aerobic conditions. On the other hand, cell size increased with adhesion of Se(0) on cell surface during anaerobic reduction. Fatty acid composition analysis demonstrated selective increase in saturated and cyclic fatty acids and decrease in unsaturated ones during aerobic transformation. Changes observed during anaerobic transformation were in surprising contrast as indicated by total absence of saturated and cyclic fatty acids. Results presented here provide evidences for putative occurrence of two distinct mechanisms involved in tolerance towards higher concentrations of selenite utilization under aerobic and anaerobic conditions. Further, prior exposure to higher concentration of Se(+4) enabled rapid adaptation indicating role of inducible system in adaptation.

Modulatory effects of Cissus quadrangularis on periodontal regeneration by bovine-derived hydroxyapatite in intrabony defects: exploratory clinical trial.

OBJECTIVE: The purpose of the present study was to clinically evaluate the efficacy of bovine-derived hydroxyapatite (HA) combined with Cissus quadrangularis (CQ), as compared to bovine-derived hydroxyapatite alone in the treatment of intrabony defects. MATERIALS AND METHODS: Twenty patients with one intrabony defect each were selected for this study. After scaling and root planing, twenty sites were randomly selected to receive either a combination of bovine-derived HA and CQ (test group) or bovine-derived HA alone (control group). Baseline and 6-month surgical reentry measurements were taken and appropriate statistical analysis was performed. RESULTS: Favorable clinical results for both hard and soft tissue measurements were obtained for both groups when compared to baseline (p < 0.001), but there was no statistically significant difference for any of the measured clinical parameters between the two groups. The mean bone fill and percentage bone fill for bovine-derived HA was 2.7 +/- 0.82 mm and 63.2 +/- 17.8%, whereas for composite graft material it was 3.3 +/- 0.82 mm and 69.8 +/- 14.2%. CONCLUSION: Although composite graft material has shown a trend towards better performance, no statistically significant intergroup difference was found. Further studies are needed to establish CQ as a modulator in periodontal regenerative therapy.

Total phenol, antioxidant and free radical scavenging activities of some medicinal plants.

Phenols, a major group of antioxidant phytochemicals, have profound importance due to their biological and free radical scavenging activities. To identify their potential sources, extracts of some plants were studied for their total phenolic content (TPC), antioxidant (AOA) and free radical scavenging activities (FRSA) by different methods at multiple concentrations followed by specific phenolic composition. The amount of TPC varied from 2.8 mg/g (Withania somnifera, roots) to 107.8 mg/g (Cassia fistula, fruits) and the AOA from 24.2% (Curcuma zeoderia, leaves) to 96.9% (Trewia nudiflora, leaves). Bark of Azadirachta indica, fruits of C. fistula, and leaves and fruits of T. nudiflora were found to have high TPC (89.8- 107.8 mg/g) and high AOA (84.8-96.9%). Promising plant parts were studied for their FRSA and reducing power (RP), where the bark of A. indica, Casuarina equisetifolia and Cinnamomum zeylanicum, flowers of Indigofera tinctoria, fruits of Lawsonia inermis, and fruits and leaves of T. nudiflora showed a very low inhibitory concentration value ranging from 0.14 to 0.26 mg/ml, efficiency concentration value from 6.1 to 11.6 mg/mg DPPH and reducing power value from 0.6 to 2.8 ascorbic acid equivalents (ASE/ml), and reasonably high values (8.5 -16.2) of anti-radical power (ARP), indicating their strong FRSA. They also showed better inhibition of hydroxyl radical induced deoxyribose degradation than that of reference standard. Fruits of C. fistula with high phenols (107.8 mg/g) showed poor reducing power (5.9 ASE/ml) and ARP (4.7); in contrast, the bark of C. equisetifolia and fruits of L. inermis were with comparatively lower phenols (72.1 and 75.8 mg/g) but exhibited good ARP (16.2 and 14.4) and reducing power (0.7 and 0.6 ASE/ ml, respectively). Some of the plants were also found effective in protecting plasmid DNA nicking induced by hydroxyl radicals generated by Fenton's reaction. They were further assayed for their specific phenolic composition through high-performance liquid chromatography and MS/MS, where the amount of caffeic acid varied from 0.312 to 0.797 mg/g, chlorogenic acid from 0.018 to 2.109 mg/g, ellagic acid from 0.009 to 0.902 mg/g, ferulic acid from 0.036 to 0.078 mg/g, gallic acid from 0.192 to 3.597 mg/g, kaempferol from 0.011 to 0.910 mg/g, quercetin from 0.047 to 1.106 mg/g and rutin from 0.059 to 2.029 mg/g.

Rhodococcus imtechensis sp. nov., a nitrophenol-degrading actinomycete.

A Gram-positive actinobacterium, strain RKJ300(T), capable of utilizing p-nitrophenol and 2,4-dinitrophenol, was isolated from a pesticide-contaminated site in India. The morphological and chemotaxonomic properties of the isolate were typical of members of the genus Rhodococcus. The DNA G+C content was 72 mol%. Strain RKJ300(T) exhibited the highest level of sequence similarity with Rhodococcus wratislaviensis NCIMB 13082(T) (99.3 %), followed by Rhodococcus opacus DSM 43205(T) (98.8 %), Rhodococcus percolatus MBS1(T) (98.6 %) and Rhodococcus koreensis DNP505(T) (98.1 %). The low levels of DNA-DNA relatedness (49-58 %) with the above micro-organisms, and the differences in the biochemical and physiological properties, suggest that strain RKJ300(T) should be classified within a novel species of the genus Rhodococcus, for which the name Rhodococcus imtechensis sp. nov. is proposed. The type strain is RKJ300(T) (=MTCC 7085(T)=JCM 13270(T)).

Phenolic contents and antioxidant activity of some food and medicinal plants.

To identify promising sources of antioxidants, some food and medicinal plants were studied for total phenolic contents and antioxidant activity. The leaves, bark and fruits of Terminalia arjuna, Terminalia bellerica, Terminalia chebula and Terminalia muelleri, the leaves and fruits of Phyllanthus emblica, and the seeds of Syzygium cumini were found to have high total phenolic contents (72.0-167.2 mg/g) and high antioxidant activity (69.6-90.6%). Leaves of Eucalyptusglobulus were a rich source of rutin, Moringa oleifera for kaempferol, aerial parts of Centella asiatica for quercetin, fruits of T. bellerica and T. chebula for gallic acid, and bark of T. arjuna, leaves and fruits of T. bellerica and bark, leaves and fruits of T. muelleri for ellagic acid.

Occurrence of yellow mosaic geminiviral disease on bitter gourd (Momordica charantia) and its impact on phytochemical contents.

Natural occurrence of yellow mosaic disease was observed on bitter gourd (Momordica charantia). Association of geminivirus with the disease was investigated through polymerase chain reaction using geminivirus-specific primers and Southern hybridization with a probe prepared from the cloned DNA of a known geminivirus. The fruits, leaves and stem of infected and healthy plants were studied for phytochemical composition. The amounts of protein were 49%, 50% and 66% higher, total carotenoids were 36%, 33% and 40% lower, vitamin C were 23%, 48% and 50% lower, total phenols were 28%, 31% and 43% lower, and antioxidant activity were 36%, 48% and 43% lower in the severely virus infected fruits, leaves and stem, respectively, as compared with healthy plants. The loss in the quantity of these phytochemicals was also observed even in mild infected plants, which further increased with the severity of the symptoms. Similarly, ethanol and 50% ethanol soluble extractive were also 25-43% lower in the fruits, leaves and stem of infected plants as compared with the healthy plants. A 45% and 54% lower caffeic acid, and 78% and 59% lower amounts of ferulic acid in the fruits and stem, respectively, and a 25% loss of gallic acid were noticed in the leaves of the severely infected plants.

Antioxidant and free radical scavenging activities of some leafy vegetables.

Some leafy vegetables were studied for their nutritional composition, antioxidant and free radical scavenging activities. The aerial parts of Coriandrum sativum, Spinacia oleracea, Trigonella corniculata and Trigonella foenum-graecum showed lower inhibitory concentration values (4.1-7.9 mg/ml), efficiency concentration values (178-321 mg/mg DPPH) and higher values of anti-radical power (0.31-0.51) as compared with their seeds. Thermal treatment reduced the total phenolic contents, antioxidant and free radical scavenging activities. The leaves of C. sativum were found with good amounts of caffeic acid, ferulic acid, gallic acid and chlorogenic acid.