Asian Journal of Plant Science and Research Volume 2 :Issue 1 : 2012

Antifungal activity of Plumbagin & Isodiospyrin from Diospyros kaki root bark

The chloroform extract of root bark of D. kaki exhibited remarkably good antifungal activity at against all the fungi. The bioassay guided fractionation of the crude extract was the done using benzene-chloroform step gradient by silica gel column chromatography. The active compounds A & B obtained were analysed by EI-MS, FTIR and 1H and 13C NMR spectroscopy. On comparision of their spectra with literature they were identified as napthoquinones, Plumbagin (5-hydroxyl, 2-methyl 1,4 -Napthoquinone) and Isodiospyrin (5-hydroxy-6-(1-hydroxy-6-methyl-5,8- dioxo-naphthalen-2-yl)-2-methyl-naphthalene-1,4-dione). The MIC values of the crude extract and compounds A & B were (160-2500 μg/ml), (1.25-20 μg/ml) and (5-160 μg/ml) & the MFC values were (630-5000), (5-160 μg/ml) and (40-160 μg/ml) respectively.

The inhibiting effect of Azadirachta indica against dental pathogens

The present study was carried out to evaluate the antimicrobial properties of neem extract against three bacterial strains causing dental caries using disc diffusion method. The pathogenic bacteria such as Streptococcus mutans, Streptococcus salivarious and Fusobacterium nucleatum were isolated from dental caries. The organic extracts of neem were prepared using different solvents such as petroleum ether, chloroform, ethanol and distilled water and were screened for its antimicrobial activity. Among the four extracts of neem, petroleum ether and chloroform extract showed strong antimicrobial activity against S. mutans with inhibition zone of 18 mm at 500 μg concentrations. Chloroform extract of neem showed strong activity against Streptococcus salivarius with inhibition zone of 18 mm. The third strain Fusobacterium nucleatum was highly sensitive to both ethanol and water extract of neems with inhibition zone of 16 mm. The results demonstrate that the chloroform extracts of neem has a strong antimicrobial activity and suggest that it can be useful in the treatment of dental caries.

Antidiabetic effect of ethanolic leaf extract of Phyllanthus amarus in alloxan induced diabetic mice

Phyllanthus amarus Schum. Thonn. is an indigenous medicinal plant, which has a folk reputation in central and southern India as hypoglycemic agent. The present investigation was carried out to evaluate the antidiabetic effect of ethanolic leaf extract of Phyllanthus amarus in alloxan induced diabetic mice. Blood glucose levels and body weights of control and diabetic mice were monitored. In the present study activities of liver enzymes such as glucokinase, glucose -6- phosphatase and fructose -1- 6-diphosphatase were also determined. Glibenclamide an antidiabetic oral drug was used as reference in the present investigation. Oral administration of ethanolic leaf extract (400 mg/kg body weight) for 45 days resulted in a significant (P<0.05) decline in blood glucose from 310.20 to 141.0 mg/dl and significant recovery in body weight of diabetic mice. There was also a significant (P<0.05) reduction in the activities of glucose-6-phosphatase and fructose-1-6-disphosphatase in liver, further there was significant (P<0.05) increase in the activity of glucokinase in liver of diabetic mice when compared with that of diabetic control. The study clearly shows that the ethanolic leaf extract of Phyllanthus amarus possesses potent antidiabetic activity.

Chitinolytic and secondary metabolite producing Pseudomonas fluorescens isolated from Solanaceae rhizosphere effective against broad spectrum fungal phytopathogens

18 Bacterial isolates were isolated from the Rhizosphere of Solanaceae family namely brinjal, capsicum, chilli and screened for the production of chitinase enzyme. Total of 10/18 isolates were the most potent chitinolytic bacterial species. Of these, 6 isolates showing zone size > 5mm were chosen for further studies. These isolates also showed varied levels of PGPR traits –siderophore, HCN, phosphate solubilisation and IAA. Dual plate assay against few selected soil borne phytopathogens- Alternaria alternata OTA36; Alternaria brassicola OCA1; Alternaria brassiceae OCA3; Collectotrichum gleosporidose OGC1 revealed broad spectrum anti-fungal activity by isolate R. The isolate R was identified as Pseudomonas fluorescens by biochemical test. Concurrent production of siderophore, IAA, HCN, phosphate solubilisation, NH3 and catalase coupled with anti-fungal activity suggests the plant growth promotion and broad spectrum biocontrol potential of this isolate. Seed bacterization of chilli seeds with Pseudomonas treatment showed 100% germination index and almost 50% reduction in disease incidence by C. gloeosporiodes OGC1 suggesting both the biocontrol and PGPR aspect of the bacteria.

Pharmacognostical evaluation of leaf buds of Ficus bengalensis L.

Ficus bengalensis belongs to family Moraceae is a large and extensively growing tree across Indian continent. The aim of present study was to investigate the pharmacognostical characters of important medicinal plant, Ficus bengalensis L. (Moraceae). The pharmacognostic studies were carried out in terms of macroscopical, microscopical characters, physicochemical parameters of F. bengalensis. Samples of different plant parts were fixed with formalin, acetic acid and ethyl alcohol (FAA), sectioned with rotary microtome and studied under microscope. Some of the diagnostic of the leaf buds were presence of uniserrate simple trichomes in sheath on both the surfaces, presence of simple starch grains, rosette calcium oxalate crystals and brown tannin content in the parenchymatous cells and presence of closely arranged thin walled rounded to tangentially elongated brown tannin color parenchymatous cells. Further, ash and extractive values were calculated as per WHO guidelines. The preliminary phytochemical screening showed the presence of sterols/ triterpenes, lactones, saponins, flavonoids, tannins, resins and carbohydrates. Various pharmacognostical characters were observed in study which can help in identification and standardization of F. bengalensis.

Hydroxy radical and DPPH scavenging activity of crude protein extract of Leucas linifolia: A folk medicinal plant

Leucas linifolia belongs to the family Lamiaceae and is a well know traditional medicinal plant in India. It is an herbaceous annual weed. In ayurveda, it is used for the treatment of cough, cold, fever, loss of appetite, skin disease, head ache, jaundice, Snake bite and scorpion sting. It has shown hepato protective activity against dgalactosamine and CCl4 induced hepatotoxicity in rats. Methanol extract of the plant has shown wound healing property. Antibacterial, antipyretic and antitussive activity of the plant have been reported which confirms its traditional medicinal usage from the time of ayurveda. In the present study, we have shown the antioxidant activity of the ammonium sulphate precipitated protein extract of Leucas linifolia. Crude protein extract of Leucas linifolia (CPLL) extract showed In vitro antioxidant activity in both hydroxyl radical scavenging and as well as in DPPH scavenging activity in Dose dependant manner . At 500μg/ml concentration of CPLL, it showed 78 and 63% inhibition, with an IC50 value of 150 and 175μg/ml in hydroxyl radical and DPPH assay respectively. As CPLL extract, scavenge hydroxyl radical more than the DPPH radical, it might have DNA protectant activity also. To conclude, CPLL showed a good antioxidant activity and might be an alternate to synthetic antioxidants available in the market.

In vitro study of antibacterial activity of Carissa carandas leaf extracts

In the present study we focus on the need for the alternative sources of the antibiotics as the pathogenic microbes are gaining resistance against standard antibiotics. Cold Aqueous, Methanol, Ethanol, Ethyl Acetate extracts of leaves of Carissa carandas in a final concentration of 500 mg/ml were evaluated for their antibacterial properties against some selected pathogenic microorganisms such as Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli using agar well diffusion method. Methanolic, Ethyl Acetate and Ethanolic extracts of Carissa carandas leaves show an average inhibitory zone diameter of 23.5, 22.0 and 21.5 mm respectively which indicate that the Methanolic extract has shown the best result having Zone of Inhibition greater than that of the standard antibiotic Tetracycline (17.0 mm).

Antimicrobial activity and phytochemical analysis of Sanseiveria roxburghiana leaf

Medicinal plants play an important role in the discovery of novel drugs used in modern medicine. The medicinal plant Sanseiveria roxburghiana leaf possesses the wide range of medicinal properties which were confirmed through literature reviews. The present study was to determine it’s leaves have any antimicrobial activity and also to check whether their phyto chemical constituents responsible for said activities. The Sanseiveria roxburghiana leaf extract was obtained by mixing the pulverized leaf materials with various solvent such as diethyl ether, ethanol and acetone, filtered with What man No.1 filter paper and concentrated to dryness. The collected extracts were tested for antimicrobial activities and the presence of chemical constituents by preliminary phytochemical analysis according to the literature. The antimicrobial susceptibility studies were conducted against gram (-) bacteria such as Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae and gram (+) such as Staphylococcus aureus. The current result supports the medicinal use of the leaf which acts as an antimicrobial agent. However further studies need to isolate the active constituents from the leaf and to study the antimicrobial activity in cellular level.

Antiepileptic activity of aqueous extract of Tricosanthes dioica Roxb.

The antiepileptic efficacy of aqueous extract of fruits of Tricosanthes dioica was evaluated by hand limb extension induced by MES and PTZ induced seizures in mice models. The aqueous extract was found to possess significant antiepileptic activity in both models and it was found to be due to activity against generalized tonic- clonic and coritical focal seizures.

Evaluation of antidiarrhoeal effect of Black pepper

Aqueous black pepper extract (75, 150, 300 mg/kg, po) was tested for its antidiarrhoeal, antimotility and antisecretory activity in mice. The methods of castor oil and magnesium sulphate induced diarrhoea were used to evaluate antidiarrhoeal activity, while charcoal meal test and castor oil induced intestinal secretions were used for testing antimotility and antisecretory activity in mice. Aqueous Black pepper extract (ABPE) produced a significant and dose dependent antidiarrhoeal, antimotility, and antisecretory effect. Preliminary phytochemical screening of ABPE showed the presence of carbohydrates, and alkaloids. It can be concluded that ABPE possesses antidiarrhoeal effect may be due to its antimotility and antisecretory effect. Antimotility and antisecretory effect of Black pepper may be due to the presence of carbohydrates and alkaloids.

Chromatographic profiling using RP-HPLC and Estimation of Biochemical Parameters of Saussera lappa

The current phytochemical investigation deals with the chromatographic fingerprinting of the methanolic extract using High Pressure Liquid Chromatography using a RP C-13 column and a Photo Diode Array Detector of the dried roots of S.lappa for the detection of the chemical constituents in the plants. Efforts were also made for the quantitative determination of the biochemical parameters for studying the biological efficacy of the plant. The current study revealed that the plant is very much rich in Phenolics and the results also denote that the plant possess a significant F/P ratio which is very near to the standard value one which implies the biological potency of the species. The HPLC profile enabled the separation of 19 constituents from the methanolic extract.

Invitro screening of antimicrobial potentials of Cissus quadrangularis L.

Cissus quadrangularis L. is a succulent plant of family Vitaceae commonly found in tropical and subtropical xeric wood. It is a fleshy, cactus like liana widely used as a common food item in India. The present study was designed to evaluate the antimicrobial activity of ethanol, diethyl ether and aqueous leaf extracts of Cissus quadrangularis L. against bacterial pathogens such as Escherichia coli, Klebsiella pneumonia, methicillin resistant Staphylococcus aureus (MRSA) and fungal pathogens such as Aspergillus flavus, Candida albicans and Fusarium solani by in vitro agar well diffusion assay. The ethanol extract of the plant was found to possess strong antimicrobial activity against tested pathogens.