Larvicidal activity of some medicinal plant extracts against filariasis fever mosquito, Culex quinquefasciatus (Say.) (Diptera: Culicidae).

OBJECTIVES: The present study was aimed to find the larvicidal activity of petroleum ether, chloroform, acetone and methanolic extracts of Dichanthium foveolatum (Del.) Roberty, Leptochloa uniflora Hochst, Pancratium triflorum Roxb and Molineria trichocarpa (Wight) N.P.Balakr against Culex quinquefasciatus. METHODS: The larvicidal potential of selected plant extracts were determined against 4th instar larvae of C. quinquefasciatus with various concentrations viz., 50, 100, 150, 200 and 250 mg/ml. The mortality counts were made after 24 h of incubation and LC50 values were calculated. RESULTS: Chloroform extracts of studied plants were showed highest larvicidal activity with remarkable irritant against the larva of C. quinquefasciatus. Highest larvicidal activity was observed in the chloroform extract of D. foveolatum against the larva of C. quinquefasciatus with LC50 = 277.03 mg/ml. The larvicidal activity of the studied plants as follows chloroform extract of D. foveolatum (LC50 = 277.03 mg/ml) >L. uniflora (LC50 = 300.56 mg/ml) >M. trichocarpa (LC50 = 306.60 mg/ml) >P. triflorum (LC50 318.42 mg/ml). The larvicidal potential of P. triflorum was as follows Chloroform > acetone > methanol > petroleum ether. The larvicidal activities of L. uniflora and M. trichocarpa were as follows Chloroform > petroleum ether > acetone > methanol respectively. The larvicidal potentials of D. foveolatum was as follows Chloroform > methanol > acetone > petroleum ether. CONCLUSION: The chloroform extract of D. foveolatum find use as broad-spectrum larvicidal agent in the near future. It is hoped that more work would be undertaken to evaluate the utility of these plant extracts for field applications considering the promising leads given by the present study.

Pancratium triflorum Roxb. (Amaryllidaceae) and Molineria trichocarpa (Wight) N.P. Balakr (Hypoxidaceae): Cytotoxic and antioxidant activities.

The present investigation was carried out to evaluate the antioxidant and cytotoxic activities of Pancratium triflorum Roxb and Molineria trichocarpa were collected from South Vagaikulam, Tirunelveli district, Tamil Nadu, India. The antioxidant activities of P. triflorum extracts were as follows with the IC50 values methanol (228.13 µg/mL) > chloroform (311.33 µg/mL) > acetone (398.08 µg/mL) > petroleum ether (410.16 µg/mL). The antioxidant activities of P. triflorum and M. trichocarpa extracts were as follows with the IC50 values methanol (80.93 µg/mL) > acetone (98.02 µg/mL) > chloroform (186.84 µg/mL) > petroleum ether (209.64 µg/mL). Among the various extracts of P. triflorum, methanolic extracts showed the strongest phosphomolybdenum reduction (140.56 g AA/100 g). Among the tested extracts, acetone extracts of M. trichocarpa showed maximum inhibition with 71.36 ±â€¯5.86%. In P. triflorum, chloroform extracts showed maximum inhibition (69.51%). The petroleum ether extract of M. trichocarpa was found to be most effective at which 50% mortality (LC50) and 90% mortality (LC90) of brine shrimp nauplii were found to be 29.22 and 184.82 mg/mL. This study results revealed the antioxidant and cytotoxic properties of P. triflorum and M. trichocarpa. Further investigations are needed to isolate and validate the active principles of the extract responsible various pharmacological properties.

Synthesis of Surface-Modified Iron Oxides for the Solvent-Free Recovery of Bacterial Bioactive Compound Prodigiosin and Its Algicidal Activity.

Prodigiosin (PG) is a bioactive compound produced by several bacterial species. Currently, many technologies are being developed for the production of PG by fermentation processes. However, new challenges are being faced with regard to the production of PG in terms of the recovery and purification steps, owing to the labile nature of PG molecules and the cost of the purification steps. Conventional methods have limitations due to high cost, low reusability, and health hazards. Hence, the present investigation was focused on the development of surface-functionalized magnetic iron oxide ([Fe3O4]F) for solvent-free extraction of bioactive PG from the bacterial fermented medium. Fe3O4 was functionalized with diethanolamine and characterized by FT-IR, diffuse reflectance spectroscopy, thermogravimetric analysis, scanning electron microscopy, and confocal microscopy. The various process parameters, such as contact time, temperature, pH, and mass of Fe3O4, were optimized for the extraction of PG using functionalized Fe3O4. Instrumental analyses confirmed that the PG molecules were cross-linked with functional groups on [Fe3O4]F through van der Waals forces of attraction. PG extracted through Fe3O4 or [Fe3O4]F was separated from the fermentation medium by applying an external electromagnetic field and regenerated for successive reuse cycles. The purity of the extracted PG was characterized by high-performance liquid chromatography, FT-IR, and UV-visible spectroscopy. The iron oxide-diethanolamine-PG cross-linked ([Fe3O4]F-PG) composite matrix effectively deactivates harmful fouling by cyanobacterial growth in water-treatment plants. The present investigation provides the possibility of solvent-free extraction of bacterial bioactive PG from a fermented medium using functionalized magnetic iron oxide.

Response surface modeling for optimization heterocatalytic Fenton oxidation of persistence organic pollution in high total dissolved solid containing wastewater.

The rice-husk-based mesoporous activated carbon (MAC) used in this study was precarbonized and activated using phosphoric acid. N2 adsorption/desorption isotherm, X-ray powder diffraction, electron spin resonance, X-ray photoelectron spectroscopy and scanning electron microscopy, transmission electron microscopy, (29)Si-NMR spectroscopy, and diffuse reflectance spectroscopy were used to characterize the MAC. The tannery wastewater carrying high total dissolved solids (TDS) discharged from leather industry lacks biodegradability despite the presence of dissolved protein. This paper demonstrates the application of free electron-rich MAC as heterogeneous catalyst along with Fenton reagent for the oxidation of persistence organic compounds in high TDS wastewater. The heterogeneous Fenton oxidation of the pretreated wastewater at optimum pH (3.5), H2O2 (4 mmol/L), FeSO4[Symbol: see text]7H2O (0.2 mmol/L), and time (4 h) removed chemical oxygen demand, biochemical oxygen demand, total organic carbon and dissolved protein by 86, 91, 83, and 90%, respectively.

Immobilization of Bacillus sp. in mesoporous activated carbon for degradation of sulphonated phenolic compound in wastewater.

Xenobiotic compounds are used in considerable quantities in leather industries besides natural organic and inorganic compounds. These compounds resist biological degradation and thus they remain in the treated wastewater in the unaltered molecular configurations. Immobilization of organisms in carrier matrices protects them from shock load application and from the toxicity of chemicals in bulk liquid phase. Mesoporous activated carbon (MAC) has been considered in the present study as the carrier matrix for the immobilization of Bacillus sp. isolated from Effluent Treatment Plant (ETP) employed for the treatment of wastewater containing sulphonated phenolic (SP) compounds. Temperature, pH, concentration, particle size and mass of MAC were observed to influence the immobilization behavior of Bacillus sp. The percentage immobilization of Bacillus sp. was the maximum at pH 7.0, temperature 20 °C and at particle size 300 µm. Enthalpy, free energy and entropy of immobilization were -46.9 kJ mol(-1), -1.19 kJ mol(-1) and -161.36 JK(-1)mol(-1) respectively at pH 7.0, temperature 20 °C and particle size 300 µm. Higher values of ΔH(0) indicate the firm bonding of the Bacillus sp. in MAC. Degradation of aqueous sulphonated phenolic compound by Bacillus sp. immobilized in MAC followed pseudo first order rate kinetics with rate constant 1.12 × 10(-2) min(-1).