36 research outputs found
Seasonal variation of atmospheric organochlorine pesticides and polybrominated diphenyl ethers in Parangipettai, Tamil Nadu, India:Implication for atmospheric transport
During 1990s, residues of several persistent organic pollutants (POPs) in different environmental matrices have been reported from a tropical coastal site, Parangipettai (PI), located along the bank of the Vellar River in Tamil Nadu. Hence to fill the existing data gap after the strict ban on several POPs, high volume air sampling was conducted in PI to study the variability of atmospheric pesticidal POPs and polybrominated diphenyl ethers (PBDEs) during summer, pre-monsoon and monsoon. Emission source regions were tracked by using five days back trajectory analysis. Derived range of air concentrations in pg/m3 were: DDTs; BDL - 1976; HCHs, 260–1135, HCB; 52–135, chlordanes; 36–135, endosulfans; 66–1013. ∑6PBDE ranged between 25 and 155 with highest concentration in summer followed by pre-monsoon and monsoon. Atmospheric DDT and HCH in PI has drastically reduced by several thousand folds from the past report thereby showing the strict ban on agricultural use of these compounds. During monsoon fresh source of o,p′‑DDT, trans‑chlordane and α‑endosulfan was evident. Usually higher level of endosulphan sulfate in PI seems to be likely affected by the air mass originating from a neighbouring state Kerela, where endosulfan has been extensively used for cashew plantations. Similarly in summer, the day showing the highest level of PBDEs, the sample was concurrently impacted by air parcel comprised of two major clusters, 1 (25%) and 2 (49%) that traversed through the metropolitan cities like Bangalore and Chennai. Dominance of BDE-99 over BDE-47 in Parangipettai is in line with the PBDE profile reported from Chennai city during the similar time frame. Average concentration of tetra and penta BDE congeners in summer samples were nearly 2–3 folds higher than pre-monsoon or monsoon. Given the fact that strong localised source for heavier BDE congeners are lacking in PI, regional atmospheric transport from the strong emission source regions in Chennai
Purification and characterization of chitinase from Alcaligenes faecalis AU02 by utilizing marine wastes and its antioxidant activity
Marine waste is an abundant renewable source for the recovery of several value added metabolites with potential industrial applications. This study describes the production of chitinase on marine waste, with the subsequent use of the same marine waste for the extraction of antioxidants. A chitinase-producing bacterium isolated from seafood effluent was identified as Alcaligenes faecalis AU02. Optimal chitinase production was obtained in culture conditions of 37°C for 72 h in 100 ml medium containing 1% shrimp and crab shell powder (1:1) (w/v), 0.1% K2HPO4, and 0.05% MgSO4·7H2O. The molecular weight of chitinase was determined by SDS-PAGE to be 36 kDa. The optimum pH, temperature, pH stability, and thermal stability of chitinase were about 8, 37°C, 5–12, and 40–80°C, respectively. The antioxidant activity of A. faecalis AU02 culture supernatant was determined through scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) as 84%, and the antioxidant compound was characterized by TLC and its FT-IR spectrum. The present study proposed that marine wastes can be utilized to generate a high-value-added product and that pharmacological studies can extend its use to the field of medicine
Fixing of chloride in concrete using admixtures
In the present investigation a method to reduce chloride in concrete has been attempted by using aluminium oxide as a chemical admixture. Studies were conducted with different amounts of admixture, namely 5 percent, 10 percent and 15 percent by weight of cement. It was concluded that aluminium oxide may effectively reduce the free chloride content in concrete and thereby reduce the risk of reinforced corrosio
Production, purification and characterization of bacteriocin from Lactobacillus murinus AU06 and its broad antibacterial spectrum
Objective: To study the production, purification and characterization of bacteriocin from Lactobacillus murinus AU06 isolated from marine sediments and its broad spectrum of inhibition against fish pathogens.
Methods: The selected strain was used in production, purification and characterized of bacteriocin. In addition, purified bacteriocin was tested for its antimicrobial activity against fish pathogens.
Results: In the present study, the bacteriocin production was found to be higher at 35 °C, pH 6.0 and was purified to 4.74 fold with 55. 38 U/mg of specific activity with the yield of 28.92%. The molecular weight of the purified bacteriocin was estimated as 21 kDa. The purified bacteriocin exhibited complete inactivation of antimicrobial activity when treated with proteinase K, pronase, chymotrypsin, trypsin, pepsin and papain. The purified bacteriocin exhibited broad inhibitory spectrum against both Gram positive and negative bacteria.
Conclusions: It is concluded that the ability of bacteriocin in inhibiting a wide-range of pathogenic bacteria is of potential interest for food safety and may have future applications in food preservative
Screening, isolation and optimization of anti–white spot syndrome virus drug derived from marine plants
Objective: To screen, isolate and optimize anti-white spot syndrome virus (WSSV) drug derived from various marine floral ecosystems and to evaluate the efficacy of the same in host–pathogen interaction model.
Methods: Thirty species of marine plants were subjected to Soxhlet extraction using water, ethanol, methanol and hexane as solvents. The 120 plant isolates thus obtained were screened for their in vivo anti-WSSV property in Litopenaeus vannamei. By means of chemical processes, the purified anti-WSSV plant isolate, MP07X was derived. The drug was optimized at various concentrations. Viral and immune genes were analysed using reverse transcriptase PCR to confirm the potency of the drug.
Results: Nine plant isolates exhibited significant survivability in host. The drug MP07X thus formulated showing 85% survivability in host. The surviving shrimps were nested PCR negative at the end of the 15 d experimentation. The lowest concentration of MP07X required intramuscularly for virucidal property was 10 mg/mL. The oral dosage of 1 000 mg/kg body weight/day survived at the rate of 85%. Neither VP28 nor ie 1 was expressed in the test samples at 42nd hour and 84th hour post viral infection.
Conclusions: The drug MP07X derived from Rhizophora mucronata is a potent anti-WSSV drug
Sulfated polysaccharides of Turbinaria conoides dose-dependently mitigate oxidative stress by ameliorating antioxidants in isoproterenol induced myocardial injured rats: Evidence from histopathological study
Objectives: In recent years, fucoidan is being marketed as a nutraceutical and food supplement because of its various pharmacological activity. Hence, we evaluated the cardioprotective activity of fucoidan extracted from Turbinaria conoides in isoproterenol induced myocardial injured rats.
Methods: Wistar rats (180 ± 20 g) were divided into eight groups of six animals each and fucoidan was administered orally in three different doses (50, 100 and 150 mg/kg), for 14 days. At the end of this period, all the rats, except control group and fucoidan alone treated groups, were administered isoproterenol for two consecutive days to induce myocardial injury. After 48 h, rats were anesthetized, sacrificed and the levels of biochemical parameters were determined and histopathological analysis carried out.
Results: Biochemical assessment of myocardial injury was done by measuring the activities of creatine kinase and lactate dehydrogenase, which were significantly elevated in the rats administered with isoproterenol. Further, pretreatment of fucoidan significantly normalized both endo and exogenous antioxidant defense system in isoproterenol induced myocardial injured rats. Therefore, fucoidan considerably reduced oxidative stress. In addition, histopathological findings were in line with biochemical findings.
Conclusion: As a consequence, fucoidan possesses cardioprotective and antioxidative effect against isoproterenol induced myocardial injury in rats
Screening, isolation and optimization of anti–white spot syndrome virus drug derived from terrestrial plants
Objective: To screen, isolate and optimize anti-white spot syndrome virus (WSSV) drug derived from various terrestrial plants and to evaluate the efficacy of the same in host–pathogen interaction model.
Methods: Thirty plants were subjected to Soxhlet extraction using water, ethanol, methanol and hexane as solvents. The 120 plant isolates thus obtained were screened for their in vivo anti–WSSV property in Litopenaeus vannamei. The best anti–WSSV plant isolate, TP22C was isolated and further analyzed. The drug was optimized at various concentrations. Viral and immune genes were analysed using reverse transcriptase PCR to confirm the potency of the drug.
Results: Seven plant isolates exhibited significant survivability in host. The drug TP22C thus formulated showed 86% survivability in host. The surviving shrimps were nested PCR negative at the end of the 15 d experimentation. The lowest concentration of TP22C required intramuscularly for virucidal property was 10 mg/mL. The oral dosage of 750 mg/kg body weight/day survived at the rate of 86%. Neither VP28 nor ie 1 was expressed in the test samples at 42nd hour and 84th hour post viral infection.
Conclusions: The drug TP22C derived from Momordica charantia is a potent anti-white spot syndrome virus drug
DISTRIBUTION AND SEASONAL VARIATION OF HEAVY METALS IN SEDIMENTS OF MUTHUPET LAGOON, SOUTHEAST COAST OF INDIA
This study deals with seasonal variation of heavy metals in sediments of Muthupet lagoon, Southeast coast of India from September 2011 to August 2012. The bulk sediments were association with sand, silt and clay. Geo-accumulation index (lgeo) was used to quantitatively assess the influences of heavy metal pollution. Heavy metals were determined by using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and the results were compared to permissible limits of WHO/USEPA. The minimum concentration of heavy metals in all the stations were found during the post monsoon and summer seasons and the maximum concentration of heavy metals in all the stations were found during the pre-monsoon and monsoon seasons. The reason for the pollution was land drainage, irrigation through channels and municipal wastes and also the peak agricultural activities due to the release of fresh water from reservoirs. Among all the metals iron was found to be maximum in all the stations in post-monsoon and summer season followed by magnesium and manganese. Apart from these three metal, all other six metals are recorded in moderate range. The reason for the high concentration of these metals are anthropogenic activity, agriculture, aquaculture and the rivers regular in and out flow throughout the study duration in the lagoon area
Effect of salinity, temperature, pH and crude oil concentration on biodegradation of crude oil by pseudomonas aeruginosa
The present study was carried out to evaluate the effect of culture conditions on biodegradation of crude oil by Pseudomonas aeruginosa. P. aeruginosa was isolated from sea water using Bushnell Haas agar supplemented with 0.1% crude oil. The strain was cultured at different temperature, pH a salinity and crude oil concentrations. Maximum growth and biodegradation occurred at 38oC, pH 8.0, 35‰ and 2.0% of crude oil. Addition of fertilizer at 0.1% concentration resulted increase in growth and biodegradation rate. Emulsification experiment revealed that P. aeruginosa showed good emulsification activity against waste motor lubricant oil, crude oil, peanut oil, diesel, kerosene, naphthalene, anthracene and xylene. Results obtained from the biodegradation experiments at different culture condition revealed that, each factor is having significant impact on biodegradation. Biodegradation of crude oil and emulsification of eight different hydrocarbons by P. aeruginosa indicated the potentiality of the strain
FIGURE 12 in Distribution of Tetraodontiformes (Family: Tetraodontidae) along the Parangipettai Coast, Southeast coast of India
FIGURE 12. Distribution of puffer fishes in all the three stations along the Parangipettai coast