Objective: To investigate the crude extract of marine actinomycetes with adverse effect locally on the adult Wister albino rats or systematically in the blood circulation. Methods: Acute toxicity, sub acute toxicity, biochemical and histopathological were tested. Results: In the results acute toxicity (LD50=2 500 μg/kg bw), sub acute toxicity study (2 500 μg/kg bw) were significant at 5% level of each experimental groups compared to the control group. Biochemical and histopathological study also showed better as compared with control group Conclusion:This crude microbial extract from Streptomyces sp. RSAUT 20 and Streptomyces scabiei (S. scabiei) RSAUK 49 is potential source for novel antimicrobial compounds. The crude extract of Streptomyces sp. RSAUT 20 and S. scabiei RSAUK 49 were tested for in vivo toxicity study.

Objective: To identify the possible antiplasmodial drugs from bacteria associated with marine sponge Clathria indica. Methods: Clathria indica samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg.mL-1) from isolated bacterial isolates were screened for antiplasmodial activity against Palsmodium falciparum and potential extracts were also screened for biochemical constituents. Results: The count of bacterial strains were maximum in November 2007 (19×104 CFU.g-1) and the average count was maximum during the monsoon season (107×10 3 CFU.g-1). Thirty one morphologically different bacterial isolates were isolated from Clathria indica and the ethyl acetate bacterial extracts were screened for antiplasmodial activity against Palsmodiumfalciparum. The antiplasmodial activity of a isolate THB23 (IC 50 28.80 μg.mL-1) extract is highly comparable with the positive control chloroquine (IC50 19.59 μg.mL-1) and 17 bacterial extracts which showed IC50 value of more than 100 μg.mL-1. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of bacterial strains after 48 h of incubation. The in vitro antiplasmodial activity might be due to the presence of carbohydrates and alkaloids in the ethyl acetate extracts of bacterial isolates. Conclusions: The ethyl acetate extracts of THB23 possesses novel compounds for the development of antiplasmodial drugs.

Objective: To identify the antiplasmodial drugs from the marine sponge Hyattella intestinalis (H. intestinalis) associated bacteria. Methods: The H. intestinalis samples were collected from Thondi coast and subjected for enumeration and isolation of associated bacteria. Filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125μg/mL) from bacterial isolates were screened for antiplasmodial activity against P. falciparum and potential extracts were also screened for biochemical constituents. Results: The count of THB isolates were maximum in November 2007 (20×10 4 CFU/g) and the average count was maximum during the monsoon season (77×103 CFU/g). A total of 29 bacteria were isolated based on the morphological characteristics and screened for antiplasmodial activity. The antiplasmodial activity of THB20 extract (IC50 41.88 μg/mL) showed at two fold concentration of IC50 value of the positive control chloroquine (IC50 19.59 μg/mL) and 14 bacterial isolates showed IC50 value of more than 100 μg/mL. Statistical analysis reveals that, significant in vitro antiplasmodial activity (P<0.05) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes showed no morphological changes in erythrocytes by the ethyl acetate extract of THB isolates after 48 h of incubation. The antiplasmodial activity of potential bacterial isolates might be due to the presence of sugars and alkaloids in the ethyl acetate extracts. Conclusions: It is concluded from the present study that, the ethyl acetate extracts of THB20 posses novel metabolites for the development of newer antiplasmodial drugs.

Objective: To identify the possible antiplasmodial compounds from Achyranthes aspera (A. aspera), Acalypha indica (A. indica), Jatropha glandulifera (J. glandulifera) and Phyllanthusamarus (P. amarus). Methods: The A. aspera, A. indica, J. glandulifera and P. amarus were collected along Palk Strait and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) of leaf, stem, root and flower extracts of A. aspera, A. indica, J. glandulifera and P. amarus were tested for antiplasmodial activity against Plasmodiumfalciparum. The potential extracts were also tested for their phytochemical constituents. Results:Of the selected plants species parts, the stem extract of A. indica showed excellent antiplasmodial activity (IC50= 43.81μg/mL) followed by stem extract of J. glandulifera (IC50= 49.14μg/mL). The stem extract of A. aspera, leaf and root extracts of A. indica, leaf, root and seed extracts of J.glandulifera and leaf and stem extracts of P. amarus showed IC 50 values between 50 and 100 μg/mL. Statistical analysis revealed that, significant antiplasmodial activity (P<0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it showed that there were no morphological changes in erythrocytes by the ethanolic extract of all the tested plant extracts. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, and tannins in the ethanolic extracts of tested plants. Conclusions: The ethanolic stem extracts of P. amarus and J. glandulifera possess lead compounds for the development of antiplasmodial drugs.

Objective: To identify the antiviral antioxidant and toxicological evaluation of marine halophyte.Methods:Mangrove associates such as Salicornia brachiata, Clerodendron inerme, Rhizophora lamarckii, Suaeda maritima were collected. In vitro antiviral studies such as HBsAg binding assay, DNA polymerase inhibition assay, RT inhibition assay were carried out. Moreover, antioxidant properties, ash content, elemental analysis, LD50 analysis were measured for theS. maritima leaf extract which was the most potent. Results: S. maritima leaf extract showed minimum concentration of IC50 value with HBsAg binding assay, DNA polymerase inhibition assay, RT inhibition assay as 325.98, 843.09 and 587.32 μg/ml concentrations respectively. Antioxidant properties of S. maritima leaf extract showed the minimum concentration (23.64±5.27μg/ml) of IC50 value with the nitric oxide scavenging assay, followed by DPPH assay (112.03±18.39μg/ml). The ash content of S. maritima leaf extract was varied between 8.05% to 87.30%concentrations. The elemental analysis of S. maritima showed the values within the limits of WHO guidelines. The lethal dose of S. maritima leaf extract was identified as 3000 mg/kg/body weight. The sub acute toxicity was not showed any significant differences with organ weights between control and extract treated animals. Biochemical parameters such as SGOT, SGPT, ALP, sugar and urea were not showed any significant variations between control and extract treated animals. But, the results of haematological parameters such as WBC (6600±234.90 cells/cumm), lymphocytes (69±14.09), polymorphs (38±9.38), eosinophils (02±0.00) were found significantly increased with extract treated animals. Phytochemical analysis of S. maritima leaf extract showed the presence of various phytochemical constituents such as reducing sugars, polyophenols, flavonoids and tannins with the leaf extract. Conclusions: The results of the present findings pave the way for the identification of novel molecules for the possible utilization of antiviral and antioxidant drugs from Suaeda maritima leaf.

OBJECTIVETo identify the hepatoprotective and in vitro antioxidant activity of Lumnitzera racemosa (L. racemosa) leaf extract.

METHODSAnimals in Group 1 served as vehicle control, Group 2 served as hepatotoxin (CCL4 treated) group, Group 3 served as positive control (Silymarin) group, and Group 4, 5 and 6 served as (75, 150 and 300 mg/kg bw p.o.) L. racemosa leaf extract treated groups. Moreover, in vitro antioxidant DPPH, hydroxyl radical scavenging activity (HRSA), NO, ferric reducing antioxidant power (FRAP), lipid hydroperoxide (LPO) and super oxide dismutase (SOD) were also analyzed for the leaf extract.

RESULTSThe levels of the serum parameters such as serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP), bilirubin, cholesterol (CHL), sugar and lactate dehydrogenase (LDH) were significantly increased in CCL4 treated rats when compared with the control group (P<0.05). But the L. racemosa leaf extract treated rats showed maximum reduction of SGOT [(210.36±19.63) IU/L], SGPT [(82.37±13.87) IU/L], ALP [(197.63±23.43) IU/L], bilurubin [(2.15±0.84) mg/dL], cholesterol [(163.83±15.63) mg/dL], sugar [(93.00±7.65) mg/dL] and LDH [(1134.00±285.00) IU/L] were observed with the high dose (300 mg/kg bw) of leaf extract treated rats. Histopathological scores showed that, no visible changes were observed with high dose (300 mg/kg bw) of leaf extract treated rats except few mild necrosis. The IC50 values were observed as (56.37±4.87) µg/mL, (57.68±1.98) µg/mL, (64.15±2.90) µg/mL, (61.94±3.98) µg/mL, (94.53±1.68) µg/mL and (69.7±2.65) µg/mL for DPPH, HRSA, NO, FRAP, LPO and SOD radical scavenging activities, respectively.

CONCLUSIONSIn conclusion, the hepatoprotective effect of the L. racemosa leaf extract might be due to the presence of phenolic groups, terpenoids and alkaloids and in vitro antioxidant properties.

Animals ; Antioxidants ; pharmacology ; therapeutic use ; Carbon Tetrachloride ; toxicity ; Chemical and Drug Induced Liver Injury ; drug therapy ; pathology ; Liver ; chemistry ; drug effects ; pathology ; Male ; Plant Extracts ; chemistry ; Plant Leaves ; chemistry ; Protective Agents ; pharmacology ; therapeutic use ; Rats ; Rats, Wistar ; Rhizophoraceae ; chemistry