ABSTRACT
Abstract Currently Streptomyces is one of the most important antibiotic producing microorganisms against several diseases. In the present study Streptomyces olivochromogenes ERINLG-261 was isolated from the soil samples of the Mudumalai hills, Western Ghats, India. Morphological, physiological, biochemical and 16S rRNA studies strongly suggested that this isolate belonged to the genus Streptomyces. ERINLG-261 showed good antimicrobial activity against different bacteria and fungi in Micromonospora fermentation medium. The active ethyl acetate extract was packed in column chromatography over silica gel which led to the isolation of 2-hydroxy-9,10-anthraquinone as the active principle. The isolated compound showed good antimicrobial activity against tested bacteria and fungi in minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) studies. The compound showed moderate in vitro antiproliferative activity against A549 and COLO320 cells. The compound was subjected to molecular docking studies for the inhibition of Topoisomerase, TtgR and Beta-lactamase enzymes which are targets for antimicrobials. Docking results of the compound showed low docking energy with these enzymes indicating its usefulness as antimicrobial agent. This is the first report of antimicrobial and antiproliferative activity of 2-hydroxy-9,10-anthraquinone isolated from Streptomyces olivochromogenes along with molecular docking studies.
ABSTRACT
Flindersine, an alkaloid isolated from Toddalia asiatica, was evaluated for their antifeedant, larvicidal and growth inhibitory activities against Helicoverpa armigera, Spodoptera litura and larvicidal activity against vector mosquitoes Anopheles stephensi and Culex quinquefasciatus. For this, leaf disc no choice method was used for agricultural pests; larvicidal activity was tested on second and fourth instar larvae for mosquitoes at different concentrations. Flindersine showed antifeedant, larvicidal and growth inhibitory activities against H. armigera and S. litura and larvicidal activity against vector mosquitoes An. stephensi and Cx. quinquefasciatus. It showed high regression (R2) values of 0.91 and 0.87 against H. armigera and S. litura, respectively for antifeedant activity. Flindersine exhibited more than 65% larvicidal activity against both the pests with LC50 values of 443.04 and 568.88 ppm and R2 values of 0.87 and 0.90 against H. armigera and S. litura, respectively. The larval and pupal duration of tested insects increased to more than five days at 1000 ppm when compared with the control. The adult emergence was reduced when the concentration of flindersine was increased. At 1000 ppm, no adult emergence was observed in both the pests. Flindersine exhibited 100% larvicidal activity against both the tested mosquitoes at 20 ppm concentration, which showed LC50 values of 2.90, 4.19, 1.68 and 2.71 ppm for 2nd and 4th instar larvae of Cx. quinquefasciatus and An. Stephensi, respectively. High regression values were observed for antifeedant, larvicidal and growth inhibitory activities. Flindersine could be used to develop an ecofriendly pesticide formulation to control the agricultural pests and vector mosquitoes.
ABSTRACT
Newly developed Phytopesticidal formulations from pongam and neem oils were evaluated for their feeding deterrent activity using leaf disc choice and no-choice methods, and genotoxic study using comet assay against Helicoverpa armigera at different concentrations of 5, 10, 15, and 20 ppm. Among various phytopesticidal formulations, neem and pongam oils at 1:1 ratio, called PONNEEM showed significant feeding deterrent activity against H. armigera at 20 ppm concentration and wasgenotoxic to H. armigera (P>0.001). The comet parameters, namely tail moment (arbitrary units), tail length (µm) and tail DNA (%) were observed at all the concentrations of PONNEEM. Statistically significant changes in all the comet parameters of H. armigera were observed at 20 ppm (P<0.001). Feeding deterrent and genotoxicity effect of PONNEEM could be applied as phytopesticide for controlling the lepidopteran insect pests.
ABSTRACT
Larvicidal activity of pectolinaringenin from Clerodendrum phlomidis was evaluated against Anopheles stephensi and antifeedant, larvicidal and growth inhibitory activities were evaluated against Earias vittella. Pectolinaringenin exhibited larvicidal activity of 100 and 98.24% against 2nd and 4th instar larvae of Anopheles stephensi at 5ppm concentration. It exhibited LC50 values of 0.35 and 0.55 ppm for 2nd and 4th instar larvae, respectively. At 100 ppm concentration, pectolinaringenin exhibited maximum antifeedant activity of 74.00% and larvicidal activity of 89.98%. The LC50 values were 36.2 and 10.23 ppm for antifeedant and larvicidal, respectively. The compound completely prevented the adult emergence at 50 and 100 ppm concentrations. This is the first report of pectolinaringenin from C. phlomidis evaluated against An. stephensi and E. vittella. The results suggested that the pectolinaringenin from C. philomidis could be used to develop a new botanical formulation to manage vector mosquitoes and agricultural pests.
ABSTRACT
Twelve fractions from chloroform extract of Clerodendrum phlomidis and 5,7-dihydroxy- 4',6-dimethoxy-flavone (pectolinaringenin) were evaluated against Helicoverpa armigera. Maximum antifeedant (89.41%), larvicidal (83.77%) and ovicidal (69.25%) activities were observed in fraction 5. The least LC50 value for antifeedant (178.09 ppm) and larvicidal (198.23 ppm) were observed in fraction 5. No adult emergence was recorded in fractions 4-6 at 1000 ppm. The oviposition deterrent activity was 100% in fraction 5 at all the concentrations. Pectolinaringenin recorded maximum antifeedant (74.68%) and larvicidal (81.11%) activities at 100 ppm; it completely prevented the adult emergence of H. armigera at 100 ppm. Maximum ovicidal activity at 100 ppm concentration was 67.95%. The oviposition deterrent activity was 100% in 100 and 50 ppm concentrations. C. phlomidis could be effectively used to develop a new formulation to control the economically important pests.
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Objective:To evaluate the larvicidal, ovicidal and repellent properties of solvent extracts of marine spongeCliona celata(C. celata)(Grant) against the malarial vectorAnopheles stephensi(An. stephensi)Liston.Methods:Marine spongeC. celata was thoroughly washed with distilled water and shade dried for48 h.Then the sponges were homogenized and extracted sequentially with hexane, ethyl acetate and methanol.Larvicidal and ovicidal activities were tested at four different concentrationsviz.,62.5,125.0,250.0 and500.0 ppm.For repellent study extracts were taken in three different concentrationsviz.,5.0,2.5,1.0 mg/cm2 at.Results:Among the three solvent extracts ofC. celata, methanol extract showed the highest larvicidal activity at500 ppm against the fourth instar larvae ofAn. stephensi.TheLC50andLC90 values ofC. celata methanol extract were recorded as80.61 and220.81 ppm againstAn. stephensi larvae respectively.High ovicidal activity of91.2% was recorded at500 ppm concentration of methanol extract.The haxane extract was found to be the most effective protectant against the adult female mosquitoes ofAn. stephensi. The mean protection time recorded in hexane extract was up to245 min at5 mg/cm2 dosage againstAn. stephensi adults.Conclusions:The screening results suggest that the hexane and methanol extracts ofC. celata are promising in mosquito control.Considering these bioactivities,C. celata could be probed further to obtain some novel pesticidal molecules.
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Objective: To assess the feeding deterrent, growth inhibitory and egg hatchability effects of PONNEEM on Helicoverpa armigera (H. armigera).Methods:growth inhibitory and egg hatchability effects on H. armigera.Results:Invariably all the newly formulated phytopesticidal oil formulations showed the feeding Five oil formulations were prepared at different ratios to assess the feeding deterrent, deterrent and growth inhibitory activities against H. armigera. The maximum feeding deterrent activity of 88.44% was observed at 15 μL/L concentration of PONNEEM followed by formulation A (74.54%). PONNEEM was found to be effective in growth inhibitory activities and egg hatchability at 10 μL/L concentration. It exhibited statistically significant feeding deterrent activity and growth inhibitory activity compared with all the other treatments.Conclusions:PONNEEM was found to be effective phytopesticidal formulation to control the larval stage of H. armigera. This is the first report for the feeding deterrent activity of PONNEEM against H.armigera. This newly formulated phytopesticide was patented in India.
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In the present study, we aimed to analyze the antinociceptive, immunomodulatory and antipyretic activities of nymphayol were investigated in wistar rats and mice. Antinociceptive effect was evaluated by acetic acid induced writhing, formalin induced paw licking and hot-plate tests. Immunomodulatory activity was assessed by neutrophil adhesion test, humoral response to sheep red blood cells, delayed-type hypersensitivity, phagocytic activity and cyclophosphamide induced myelosuppression. Antipyretic activity was evaluated by yeast induced hyperthermia in rats. Nymphayol produced significant (p<0.05) antinociceptive activity in acetic acid induced writhing response and late phase of the formalin induced paw licking response. Pre-treatment with nymphayol (50 mg/kg, oral) evoked a significant increase in neutrophil adhesion to nylon fibres. The augmentation of humoral immune response to sheep red blood cells by nymphayol (50 mg/kg) was evidenced by increase in antibody titres in rats. Oral administration of nymphayol (50 mg/kg) to rats potentiated the delayed-type hypersensitivity reaction induced by sheep red blood cells. Treatment with nymphayol showed a significant (p<0.05) reduction in pyrexia in rats. The results suggest that nymphayol possesses potent anti-nociceptive, immunomodulatory and antipyretic activities.
Subject(s)
Animals , Mice , Rats , Acetic Acid , Administration, Oral , Cyclophosphamide , Erythrocytes , Fever , Flowers , Formaldehyde , Hypersensitivity , Hyperthermia, Induced , Immunity, Humoral , Neutrophils , Nylons , Nymphaea , Rats, Wistar , Sheep , YeastsABSTRACT
Antifeedant and growth regulating activities of PONNEEM, an oil formulation containing neem and pungam (karanj) oils were evaluated along with individual neem and karanj oils and Nimbicidine, a commercial neem-based pesticide against fourth instar larvae of Spodoptera litura (Fab.). Among all the treatments, PONNEEM recorded the maximum antifeedant activity (88.6%) at 0.6%. Neem and karanj individual treatments as well as PONNEEM extended larval duration compared to control. Pupal weight and fecundity were significantly reduced and pupal period was greatly increased by PONNEEM treatment compared to other treatments. The PONNEEM was found to be compatible with Trichogramma chilonis Ishii, an egg parasitoid of many lepidopteran pests, at 0.15, 0.3 and 0.5% concentrations. PONNEEM did not affect the parasitoid emergence significantly at 0.3% concentration compared to control. PONNEEM also showed growth disruption activity against fourth instar larvae.
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Objective: To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura). Methods:Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0%and 0.5%for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculated using probit analysis. Results:Hexane crude extract showed maximum ovicidal activity of 61.94%at 5.0%concentration with a correlation value of r2=0.81, and least LC50 value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61%at 1 000 mg/kg with the LC50 value of 318.65 mg/kg and LC90 value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r2=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction. Conclusions:As per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests.
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Objective:To isolate novel actinomycetes and to evaluate their antibacterial activity. Methods:Three soil samples were collected from Vengodu (village) in Kanchipuram district, Tamil Nadu, India. Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar. Results: Totally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar. All the isolates were screened for antibacterial activity by cross streak method. Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method. Isolation of bioactive compounds from significant active isolates was done by using different media. The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) using 16s rRNA sequence method. The hexane, ethyl acetate, dichloromethane and butanol extracts of VAS 10 were tested against bacteria. The maximum antibacterial activity was observed in dichloromethane and ethyl acetate;maximum zones of inhibition were observed against Enterococcus durans. The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively. Conclusions: The present study showed that among the isolated actinomycetes, Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) showed good antibacterial activity against the tested bacteria.
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Objective: To evaluate the ovicidal activity of different botanical oil formulations againstHelicoverpa armigera and Spodoptera litura. Methods: Different botanical oils were formulated with different ratio to evaluate the ovicidal activity against H. armigera and S. litura at 5, 10, 15 and 20μl/L concentrations. Results: All the oil formulations showed the ovicidal activity against H. armigera and S. litura. The maximum ovicidal actvity of 76.74 and 69.36% was noticed at 20μl/L concentration in formulation 3 PONNEEM. Formulation 4 Pongam oil showed lower ovicidal activity of 31.34 and 24.76% against H. armigera and S. litura respectively. Among the formulations, PONNEEM exhibited statistically superior ovicidal activity against both insect pests. Conclusions: the present study clearly showed PONNEEM as a pontenial biopesticide to control the egg stage of economically important pests of H. armigera and S. litura. This is the first report for the ovicidal activity of PONNEEM against these two insect pests.