mL Of Plant Extract Research Articles

Optimization and bio-fabrication of phyto-mediated silver nanoparticles (Ag-NPs) for antibacterial potential

This report examines the bio-fabrication of silver nanoparticles (Ag-NPs) utilizing AgNO3 and leaf extract of Crataegus monogyna as the precursor material. In order to maximize the antibacterial efficacy against Staphylococcus aureus, Proteus mirabilis, Klebsiella pneumoniae and Pseudomonas aeruginosa, the reaction conditions for the green fabrication of Ag-NPs were optimized. A one factor at a time approach (volume concentration of extract, volume concentration of AgNO3, pH and temperature) was used to optimize the best condition, and results were assessed through UV-visible spectroscopy and particle size distribution. The results showed that 20 mL of plant extract, 80 mL of AgNO3, pH 08, 100 °C temperature were the optimum reaction conditions under which we obtained the smallest Ag-NPs (7 nm). The scanning electron microscopy and X-ray diffraction analysis confirmed the spherical and crystalline nature of Ag-NPs. The antibacterial activity assay demonstrated a high antibacterial effect of Ag-NPs against S. aureus, P. mirabilis, K. pneumoniae and P. aeruginosa, and that impact was greater with smaller-sized nanoparticles (7 nm). This study shows that leaf extract of C. monogyna is a possible medium for the green fabrication of Ag-NPs, and control over reaction factors can establish the characteristics and antibacterial effectiveness of Ag-NPs. Communicated by Ramaswamy H. Sarma

Green synthesis, antioxidant and anticancer activities of TiO2 nanoparticles using aqueous extract of Tulbhagia violacea

In this study, titanium oxide nanoparticles represented as TiO2(1), TiO2(2), and TiO2(3) were prepared using different volumes (10, 20, and 40 mL, respectively) of aqueous leaf extract of Tulbhagia violacea. The physicochemical characteristics of these materials were established using X-ray diffraction (XRD), ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy. The obtained XRD pattern confirmed the formation of the anatase TiO2 phase in all the prepared materials irrespective of the volume of extracts used. Nevertheless, TiO2(2) nanoparticles obtained using 20 mL of plant extract showed the highest crystallinity. The maximum absorption wavelength found in the region between 260 and 267 nm in the UV–vis spectroscopy study suggested a quantum size effect. All synthesized TiO2 nanoparticles appeared to possess varying shapes and sizes, mostly dominated by rectangular shapes that were irregularly distributed across the materials. The material was found to be highly agglomerated due to the high calcination temperature. The antioxidant assay showed weak to moderate activity relative to the standard ascorbic acid. Also, compared to 5-Fluorouracil, all the nanoparticles exhibited moderate cytotoxicity against HEK 293 and HeLa cell lines. The TiO2 (1) showed the best specificity towards the cancer cell line with IC50 values of 29.73 and 34.27 µg/mL for both HeLa and HEK 293 cell lines, respectively. This suggests its potential as a promising candidate in applications where it is important to protect healthy cells.

A rapidDNAextraction method for the detection ofClavibacter sepedonicusandRalstonia solanacearumin potato samples in a multiplexPCRtest

AbstractA method is described that generates DNA extracts suitable for the detection ofClavibacter sepedonicusandRalstonia solanacearumin potato samples, without the need for laborious, time‐consuming extraction protocols or expensive kits and laboratory equipment. Furthermore, a multiplex test is presented that allows the simultaneous detection of both pathogens in one standard PCR reaction. The methods described here allowed the detection of both bacteria in cell densities of 103cells per mL of plant extract, thus fulfilling the demands of official testing schemes, e.g. in the European Union. High potato starch content did not affect analytical sensitivity, and high concentrations of one pathogen did not impede the detection of the other. This method might be useful for all laboratories worldwide carrying out medium‐ to large‐scale potato testing for bacteria, and also seems to be suitable for the detection of virus diseases relevant for seed potato certification.

Green Synthesis and Characterization of Iron Nanoparticles Synthesized from Aqueous Leaf Extract of Vitex leucoxylon and Its Biomedical Applications.

The cold extraction method was used to obtain the aqueous extract of Vitex leucoxylon leaves in a ratio of 1:10. Iron nanoparticles (FeNPs) were synthesized using aqueous leaf extract of V. leucoxylon as a reducing agent. The phytoreducing approach was used to make FeNPs by mixing 1 mL of plant extract with 1 mM of ferric sulfate. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Ultraviolet–visible spectroscopy (UV-Vis), and energy-dispersive X-ray spectroscopy were used to examine the synthesized FeNPs. The reducing reaction was shown by a change in the color of the solution, and the formation of black color confirms that FeNPs have been formed. The greatest absorption peak (max) was found at 395 nm in UV-Vis spectral analysis. The FTIR spectra of V. leucoxylon aqueous leaf extract showed shifts in some peaks, namely 923.96 cm−1 and 1709.89 cm−1, with functional groups carboxylic acids, unsaturated aldehydes, and ketones, which were lacking in the FTIR spectra of FeNPs and are responsible for FeNPs formation. FeNPs with diameters between 45 and 100 nm were observed in SEM images. The creation of FeNPs was confirmed by EDX, which shows a strong signal in the metallic iron region at 6–8 Kev. XRD revealed a crystalline nature and an average diameter of 136.43 nm. Antioxidant, anti-inflammatory, cytotoxic, and wound healing in vitro tests reported significant activity of the FeNPs. The cumulative findings of the present study indicate that the green synthesis of FeNPs boosts its biological activity and may serve as a possible dermal wound-healing agent and cytotoxic agent against cancer. Future study is needed on the identification of mechanisms involved in the synthesis of FeNPs by V. leucoxylon and its biomedical applications.

Anti Microbial Activity of Musa sapientum Mediated Copper Nanoparticle against Oral Pathogens: An In-vitro Study

Background: Musa sapientum is a useful medicinal plant from the Musaceae family. Copper nanoparticles with a high surface to volume ratio can also be used as antifungal and antibacterial agents. The aim of the study is to access the antimicrobial activity of musa sapientum mediated copper nanoparticle against oral pathogens
 Materials and Methods: Plant extract was prepared by 1g of musa, was weighed aseptically and then dissolved in 100 ml of distilled water. Then the solution is boiled for about 5 minutes at a temperature of about 60-80 degree Celsius and then allowed to cool down followed by filtration of extract. The copper solution was prepared by dissolving 20 millimolar of copper sulphate in 80 ml of distilled water followed by 20 ml of plant extract and then the mixture is placed in the shaker for the synthesis and then allowed to mix for about 1 hour then the first reading was taken using UV spectrum and noted down. Antimicrobial activity was done against the strain of S. aureus, S. mutans, E. faecalis. Muller Hinton agar was utilised for this activity to determine the zone of inhibition different concentrations were loaded in the plates and incubated for 24 hrs 37 degree celsius after the incubation time the zone of inhibition was measured. Antifungal activity of zinc oxide nanoparticles was done against the strain Candida Albicans.
 Results: For the study, descriptive statistics was used. For 100 μL concentration 11 mm zone of inhibition was seen when compared to the standard drug Amoxyrite which had a zone of inhibition of 36mm, which means that the antimicrobial activity was low in case of E. Faecalis. In C. Albicans, at 100μL concentration 14mm zone of inhibition was seen, but the standard fluconazole had only a zone of inhibition of 10mm, which means antimicrobial activity was good in case of C. albicans which showed more zone of inhibition. For S. aureus, at 100μL 13mm zone of inhibition was seen, the standard value showed 28mm zone of inhibition which means there is less zone of inhibition when compared to standard drug. For S. mutans, at 100μL concentration 18mm zone of inhibition was seen and when compared to the standard value which was 23mm which showed poor antimicrobial activity.
 Conclusion: The research concludes that musa sapientum mediated copper nanoparticles showed a moderate antimicrobial activity against the pathogens Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis and Candida albicans.

Total polyphenol content and antioxidant capacity of allium plants and their correlation with antibacterial and antifungal activity

Aim. To determine the total polyphenols and antioxidant capacity and their correlation with antimicrobial and fungicidal properties in some species of the genus Allium growing in Tajikistan.Materials and methods. The objects of the study were 15 kinds of the Amaryllidaceae family. Antibacterial onions were studied by the disk diffusion method against 4 types of microorganisms (test strains) and 1 type of yeast fungus. In the presence of total polyphenols, the content in μg of Gallic acid (GA) per ml of plant extract was measured. To determine the antioxidant activity, a solution of ABTS K2S2O8 was used. Trolox was used as a standard.Results. The maximum content of total polyphenols is characterized by ethanol extracts of A. Carolinianum, A. altaicum, A. elatum, A. oschaninii, A. ramosum, A. hymenorhisum. At the same time, their lowest amount was found in the bulbs of A. longicuspis. A. shoenoprasum, which is statistically significantly lower than in all the above-listed species of this plant group. The extracts from the stems of A. carolinianum, A. elatum, and A. pamiricum had the highest antioxidant effect. There is a direct weak correlation between biologically active components with antimicrobial and fungicidal activity in A. oshaninii and A. suworowii, depending on the altitude gradient.Conclusions. The results allow suggesting that the above-ground and underground parts of some wild-growing endemic species of the genus Allium have different degrees of antioxidant activity due to total polyphenols. The content of total polyphenols and the antioxidant capacity of extracts obtained from various plants in different in large ranges. In some cases, there are direct correlations between the content of polyphenols, antioxidant properties, antimicrobial and fungal properties.

Preparation of new biocompatible polymeric nanofibers containing Daphne macronata extract and evaluation of its antimicrobial activity

Background and Objective: Daphne mucronata is one of the species of Daphne genus in Iran that has unique biological properties and has been used as a medicinal plant for a long time. In this study, biocompatible polymer nanofibers by polyvinyl alcohol and Daphne macronata extract were prepared as a high-efficiency antimicrobial coating by electrospinning method, and its antimicrobial activity on three species of Gram-positive and two species of Gram-negative bacteria and one species of fungi were investigated.Experimental: In this study, a polymer solution with a weight/weight percentage of 12% polyvinyl alcohol polymer was prepared and 2 ml of plant extract was added to 10 ml of a polymer solution. To produce nanofibers, the optimum parameters of the electrospinning device including 17 kV voltage, injection rate 3 mL.h-1, tip needle to collector distance 7 cm, and collector speed 100 rpm were adjusted. Results: After preparing the polymer layer, the morphology and diameter of the nanofibers were determined with the scanning electron microscope, and the average diameter of the nanofibers produced under optimal conditions was 80 nm. Examination of the antimicrobial activity of this coating showed that the structure has a considerable antimicrobial activity on bacteria so that the greatest antimicrobial effect on Gram-positive bacterium was observed against Staphylococcus pyogenes with an inhibition zone diameter of 14 mm.Conclusion: As a result, this compound can be used as an antimicrobial coating in biology and medicine for packing or wound dressings.

Bio fabrication of gold nanoparticles and their combination with chemotherapy and ultrasound for effective treatment of tumors

Chemotherapy is one of the important medical option for the cancer therapy, but still new combination of therapeutic treatment methods are needed to achieve efficient anti tumor activity. In this work, Pueraria lobata leaf extract was utilized as a bio reductant for the fabrication of the Gold nanoparticles (Au-NPs) by an ecological approach without using any harmful chemical. This work also evaluates whether the combined effect of chemotherapy along with Au-NPs and Ultrasound (US) is effective over the tumors or not. About 10 mL of plant extract was added to 1mM of HAuCl4 solution (20.0 mL) and pH was maintained at 12 and allowed for stirring for half an hour. The change in solution color from yellow to purple signified the Au-NPs formation. XRD results and TEM images confirmed the formation of crystalline Au-NPs with sizes ranging from 23-30 nm. Further, biological studies revealed that the combination of Au-NPs and US along with chemotherapy improved the impact of anti-cancer drug. In conclusion, Pueraria lobata leaf extract mediated synthesis of Au-NPs by an eco-friendly approach was reported in this work. The plant biomolecules of the extract were involved in the reduction and capping of the Au-NPs formed. The major conclusion is that addition of Au-NPs with chemotherapy and ultrasound has shown more effective anti-tumor activity.

The Solanum glaucophyllum Desf. extract reduces mineralized matrix synthesis in osteogenically differentiated rat mesenchymal stem cells in vitro.

The Solanum glaucophyllum Desf. has been used to treat and prevent diseases in human and veterinary medicine. On the other hand, plant poisoning causes several bone diseases, among them osteoporosis, which is characterized by osteoblastic hypoplasia. Because the osteoblast is a cell derived from the differentiation of mesenchymal stem cells (MSCs) from bone marrow, the hypothesis is that the plant reduces the osteogenic differentiation of MSCs. The objective of this study was to evaluate the effects of S.glaucophyllum Desf. extract on MSCs cultured in osteogenic differentiation medium. We determined by liquid chromatography that 1ml of plant extract contained 3.8μl of 1,25(OH)2 D3 (calcitriol). Four groups of MSCs cultivated in osteogenic medium were evaluated as follows: (a) treated with 100μl of extract/L containing 0.4μg/L of calcitriol; (b) treated with 1ml of extract/L containing 4μg/L of calcitriol; (c) treated with 5ml of extract/L containing 20μg/L of calcitriol; and (d) a control group without extract. We performed alkaline phosphatase activity assay, analysis of MTT conversion to formazan, and evaluated the percentage of cells, and number and diameter of mineralization nodules. The expression of gene transcripts for osteopontin, bone sialoprotein and BMP-2 was analysed by RT-qPCR. After 21days, there was a significant reduction in MTT conversion to formazan in treated groups, of the cellularity in the group with 5ml of extract/L, and in the number and size of mineralization nodules in the groups treated with 1 and 5ml of extract/L. The 5ml extract/L concentration also reduced transcript expression of osteopontin. It is concluded that S.glaucophyllum Desf. at concentrations of 1 and 5ml extract/L reduced mineralized matrix synthesis in MSCs cultivated in osteogenic differentiation medium, which suggests that this is one of the mechanisms by which osteoporosis occurs in intoxicated animals.

Efeitos do extrato aquoso de Ipomoea carnea subsp. fistulosa sobre o desenvolvimento de larvas de Chrysomya albiceps (Wiedemann, 1819) (Calliphoridae: Diptera)

Plantas do gênero Ipomoea são conhecidas por ocasionarem intoxicações letais a animais de produção. Porém, pouco se sabe sobre os efeitos de suas toxinas em invertebrados de importância médico-veterinária e forense. Esta pesquisa visou analisar o efeito do extrato aquoso em diferentes concentrações de Ipomoea carnea subsp. fistulosa sobre o tempo de desenvolvimento larval e corporal de imaturos de Chrysomya albiceps (Wiedemann, 1819), uma espécie de importância forense no Brasil. Larvas L1 de C. albiceps foram submetidas a três tratamentos: controle (apenas carne moída), 40 mL (40 mL de extrato de I. carnea subsp. fistulosa para 80 g de carne moída) e 80 mL (80 mL de extrato de I. carnea subsp. fistulosa para 80 g de carne moída). Os tempos de desenvolvimento larval até a fase de pupa foram estatisticamente maiores nos tratamentos de 40 e 80 mL, respectivamente, em relação ao controle. Foi observada também diferença significativa no comprimento total das larvas do controle com os demais tratamentos. Os resultados indicam que o contato com as toxinas presentes em I. carnea subsp. fistulosa retarda o desenvolvimento de larvas de C. albiceps.

Rat mesenchymal stem cell cultures as a model to elucidate the cellular and molecular pathogenesis of bone metaplasia induced by Solanum glaucophyllum intoxication

The hypothesis of this experiment is that mesenchymal stem cells (MSCs) are involved in the genesis of the bone metaplasia caused by Solanum glaucophyllum intoxication. We determined using liquid chromatography that 1 mL of plant extract contained 3.8 μl of 1,25(OH)2D3. The ability of 100 μL, 1 mL and 5 mL of extract/L, containing 1 nM (0.4 μg/L), 10 nM (4 μg/L) and 50 nM (20 μg/L) of 1,25(OH)2D3, respectively, in inducing the osteogenic differentiation in bone marrow MSCs from rats was tested. At the concentrations of 1 and 5 mL of extract/L of culture medium without osteogenesis-inducing factors, the plant extract induced the osteogenic differentiation of the MSCs, as was evidenced by the greater synthesis of mineralized matrix. At the higher concentration (5 mL of extract/L), an increase in the relative expression of BMP-2 gene was observed. It was concluded that rat bone marrow MSC culture is a good model for studying the effects of the S. glaucophyllum extract on the osteogenic differentiation of undifferentiated cells. Also, S. glaucophyllum extracts containing 10 nM (4 μg/L) and 50 nM (20 μg/L) of 1,25(OH)2D3 induce the osteogenic differentiation of MSCs, suggesting that this is one of the mechanisms by which S. glaucophyllum causes bone metaplasia.

Study on the photocatalytic and antibacterial properties of silver nanoparticles synthesized by a green approach

Silver nanoparticles (AgNPs) have potential applications in several fields, mainly when they are synthesized by a green method. In the present work, the photocatalytic and antibacterial properties of silver nanoparticles biosynthesized using aqueous extracts of a variety of Eriobotrya japonica were investigated. The effects on the nanoparticles characteristics of parameters such as extract volume, stability, and reaction temperature were studied. The structural characterization showed that the synthesized nanoparticles have spherical morphology mostly with a size range of 10–60 nm. The increase of biosynthesis reaction temperature leads to an increase in the AgNPs concentration. However, the size and size distribution increased, resulting in a bimodal distribution. Therefore, the best results were obtained at room temperature with 4 ml of plant extract. According to FTIR results, the reduction of Ag ions and the subsequent nanoparticles stabilization are attributed to phenolic compounds from leaves extract. The antibacterial properties of the nanoparticles were evaluated. The bacteria analyzed were E. coli, P. aeruginosa, and S. aureus. The results demonstrate the capacity of the nanoparticles to inhibit the growth of gram-negative and gram-positive bacteria. These antibacterial properties depend on the concentration of nanoparticles. Finally, the catalytic activity of silver nanoparticles was analyzed. The results showed the excellent properties of nanoparticles to degrade methylene blue and methyl orange. Moreover, the rate and efficiency of degradation depending on the nanoparticles concentration, obtaining the best results when the highest concentration (60 μg ml−1) was employed. Therefore, silver nanoparticles synthesized by green synthesis are an excellent candidate for antibacterial and catalytic applications.

Screening of antioxidant property of Eclipta alba

The aim of the study was to examine the possible antioxidant activities of the methanolic extracts of medicinal plants, Eclipta alba. We examined for such properties such as nitric oxide radical scavenging assay, DPPH radical scavenging activity. Free radicals are atoms or molecules that have one or more unpaired electrons on its outer orbital, highly reactive, and could damage cell inside human body. Human body produce antioxidant to neutralize free radicals, but human ageing and stress oxidative conditions would increase the formation of free radicals, therefore an exogenous antioxidant are needed. Asteraceae is the largest family among the plant kingdom, therefore it has a great potential as source of exogenous antioxidant. The flavonoid content of the plant extract was estimated by the method of (Lamaison and Carnat, 1990). Briefly 1.0 ml of plant extract was mixed with 1.0 ml of aluminium chloride reagent and resultant colour was read at 430 nm. The flavonoid content of the extract was expressed as mg quercetin equivalent/gm dry wt. of extract. The coarsely powdered plant materials of Eclipta alba (2000 g) were extracted separately to exhaustion in Soxhlet apparatus for 72 hours by using methanol solvent The crude extract was filtered using 125 mm Whatman® qualitative filter paper under sterile condition. A methanol solution of the sample at various concentrations was added to 0.5 ml of 0.1 mM methanolic solution of DPPH and allowed to stand for 30 min at 25°C in darkness. The absorbance of the sample was measured at 517 nm. A 0.1 mM solution of DPPH in methanol was used as control, whereas ascorbic acid was used as reference standard. The absorbance of the pink chromophore formed during the diazotization of the nitrite with sulphanilamide and the subsequent coupling with naphthyl ethylenediamine dihydrochloride was measured at 546 nm. The percentage of inhibition of the extract shown 39% in 25µg and in 100µg it was 73 percent.

Purification of simulated waste water using green synthesized silver nanoparticles of Piliostigma thonningii aqueous leave extract

Synthesis of nanoparticles from various biological systems has been reported, but among all such systems, biosynthesis of nanoparticles from plants is considered the most suitable method. The use of plant material not only makes the process eco-friendly, but also the abundance makes it more economical. The aim of this study was to biologically synthesize silver nanoparticle using Piliostigma thonningii aqueous leaf extract and applied in the purification of laboratory stimulated waste with optimization using the different conditions of silver nanoparticle production such as time, temperature, pH, concentration of silver nitrate and volume of the aqueous extract. The biosynthesized silver nanoparticles were characterized by UV–visible spectrophotometry, nanosizer, energy dispersive x-ray analysis (EDX), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy. The time intervals for the reaction with aqueous silver nitrate solution shows an increase in the absorbance with time and became constant giving a maximum absorbance at 415 nm at 60 min of incubation. The pH of 6.5, temperature 65 °C, 1.25 mM of silver nitrate and 5 ml of plant extract was the best condition with maximum absorbance. The results from nanosizer, UV–vis and TEM suggested the biosynthesis silver nanoparticle to be spherical ranging from 50 nm to 114 nm. The EDX confirmed the elemental synthesis of silver at 2.60 keV and FTIR suggested the capping agent to be hydroxyl (OH) group with –C=C stretching vibrations. The synthesized silver nanoparticle also shows heavy metal removal activity in laboratory simulated waste water. The safety toxicity studies show no significant difference between the orally administered silver nanoparticles treated water group and control group, while the histopathological studies show well preserved hepatic architecture for the orally administered silver nanoparticle treated waste water group when compared with the control group. Therefore, it can be concluded that the biosynthesized silver nanoparticles have efficient ability in heavy metal removal without sub chronic adverse effects in experimental rats.

Bioethanol Production from Elephant Grass (<i>Pennisetum purpureum</i>)

The problem of global warming has been undeniably accepted worldwide. One of the causes of this situation is the increase in the greenhouse gases. This study was carried out to produce bio-ethanol from elephant grass (Pennisetun purpureum). The grass was sun dried, milled and pretreated by steam explosion method at 160oC. Seven sets of 350 g of the sample was mixed with 350 ml of water boiled at 100oC and left to stand for 24 hours, after which it was sieved. Sets of 25 ml extract was decanted into reactor bottles and autoclaved at 121oC, at 15 psi for 15 mins. Five milliliter (5 ml) of Saccharomyces cerevisiae of 0.98 optical density and 5 ml of Aspergillus spp., was then introduced into the reactors. The reactor bottles were corked properly, sealed with aluminum foil and rocked at room temperature for 6 days. Samples were pooled and taken for distillation at 24 hours intervals. Ethanol yield increased from day one to sixth day, which had ethanol yield of 9 ml from 25ml of plant extract while the control had 0.5 ml ethanol yield on day 6. The pH of the medium decreased from 6.50 to 6.00 for the reactor bottle containing microbial inoculants and the control had a pH of 5.53 to 5.85 while the temperature of the reactor bottle containing the microbial inoculants increased from 25oC to 30oC and the control had a temperature of 24oC and 28oC. The optimized condition for ethanol production was established at pH 6.0 and temperature 30°C. Under these conditions, an ethanol yield of 9 ml was obtained from 25 ml of plant extract. The control experimental setup showed low ethanol yield of 0.5 ml of 25 ml of plant extract.Keywords: Elephant grass, bioethanol, reactor, Sacharromyces cerevisiae

Mosquito Larvicidal Activity of Fractionated Methanolic Extractof <i>Rhizophora mucronata</i> Stilt Root and <i>Sesuvium portulacastrum</i> against Dengue Larvae

To determine the larvicidal activity of fractionated methanolic extract of stilt root of Rhizophora mucronata and leaf of Sessuvium portulacastrum against dengue larvae. Fractionated methanolic extracts of stilt root of Rhizophora mucronata and leaf of Sessuvium portulacastrum were dissolved in dimethylsulfoxide (DMSO) to prepare a graded series of concentration. Batches of 25 early 4 th instars larvae of dengue were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01-0.1 mg). Each experiment was conducted in three replicates. A control group consisted of 1 mL of DMSO and 99 mL of distilled water only. After 24 h, the percentage of mortality was identified with the formula: % of extraction= wt of the extract/wt of the plant material X 100. The fractionated leaf extracts showed maximum larvicidal activity fractionated extract 3 showed minimum level of LC 50 value (0.051±0.2 (0.41-0.602). Simultaneously, the fractionated stilt root extract of Rhizophora mucronata showed maximum larvicidal activity and (RF-2) showed minimum level of LC 50 value (0.51±0.29 (0.45-0.65). It can be concluded from the present study that, the fractionated methanolic extracts of stilt root of Rhizophora mucronata and leaf of Sessuvium portulacastrum against dengue larvae possess active compounds for development of larvicidal activity.

Feeding Deterrent Activity of <em>Melia azedarach</em> Linn. and <em>Phytolacca dodecondra</em> (L'Herit) Plant Extracts Against Cabbage Flea Beetle, <em>Phyllotreta cruciferae</em> (Goeze)

Aim of the study was to evaluate feeding deterrent activity of cold and hot water extracts of <em>Melia azedarach</em> and <em>Phytolacca dodecondra</em> plant parts against cabbage flea beetle, <em>Phyllotreta cruciferae</em>. Tap water was used for cold water extraction and 100°C boiled water was used for hot water extraction. Five concentrations (w/v) such as 0.625, 1.25, 2.5, 5 and 10 g, respectively of powder/100 mL of water was used to check feeding deterrent activity by leaf discs method. Feeding deterrent activity of plant extracts was monitored for 24, 48, 72 and 96 h, respectively post exposure period with 24 h interval. In addition, mean number of feeding holes were recorded after 96 h post exposure period. The cabbage leaf disc treated with 10 g/100 mL of plant extracts recorded 100% feeding deterrent activity after 24 h exposure period. After 48 h exposure period, except for <em>Melia</em> mature fruit (96.6%) remaining all the extracts recorded 100% feeding deterrent activity at 10 g/100 mL treatment. After 72 h exposure period, at higher concentration (10 g/100 mL), feeding deterrent activity of cold water extract of <em>Phytolacca</em> leaf (96.6%) was on par with hot water extract of <em>Phytolacca</em> leaf (96.6%) and immature fruit (96.6%). After 96 h exposure period, except for hot water extract of <em>Phytolacca</em> leaves (93.3%), remaining all observed 100% feeding deterrent activity at higher concentration. The mean numbers of feeding holes were decreased in increased concentration of the plant extracts. Irrespective of the concentrations, minimum feeding hole was observed at 10 g/100 mL of cold and hot water extract treatment. These two plant extracts proved to be effective by preventing feeding nature of the insects under laboratory. If these plant extracts may provide similar results under field condition it may be useful for controlling flea beetles damage in cabbage crops.

Bioactivity of sea grass against the malarial fever mosquito Culex quinquefasciatus

ObjectiveTo identify the larvicidal activity of the seagrass extracts against Culex quinquefasciatus (Cx. quinquefasciatus) MethodsSeagrass extracts, Halodule pinifolia (H. pinifolia), Cymodocea serrulata (C. serrulata) and Thalasia testudinum (T. testudinum) were dissolved in dimethylsulfoxide to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Cx. quinquefasciatus were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01 mg−0.1 mg). After 24 h the mortality rate was identified with the formulae [(% of test mortality − % of control mortality)/(100 − % of control mortality)]×100. Each experiment was conducted with three replicates and a concurrent control group. A control group consisted of 1 mL of dimethylsulfoxide and 199 mL of distilled water only. ResultsThe root extract of H. pinifolia showed maximum larvicidal activity with minimum concentration of extract of LC50 value of (0.614±0.006) μg/mL with lower confidence limit-upper confidence limit value of (0.052–0.072) and LC90 value of 0.9120 μg/mL followed by leaf extract of C. serrulata LC50 value of (0.074±0.008) μg/mL and LC90 value of 0.1487 μg/mL. T. testudinum leaf extract showed LC50 value of (0.082±0.006) μg/mL. The regression equation of root and leaf extract of H. pinifolia for 4 th instar larvae of Cx. quinquefasciatus were Y=5.229+1.36x (R2=0.993) and Y=2.369+1.21x (R2=0.878) respectively and analysis of variation was significant at P<0.05 level. The result of the preliminary phytochemical constituents showed the presence of saponin, steroids, terpenoid, phenols, protein and sugars. ConclusionsFrom the present study the ethanolic extracts of seagrass of H. pinifolia possess lead compound for development of larvicidal activity.

Compatibilidade de nematóides entomopatogênicos e extratos vegetais aquosos visando o controle da mosca-das-frutas Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)

Currently, the fruit fly Ceratitis capitata (Diptera: Tephritidae) has been controlled mainly by the chemical method, which is responsible for environmental and public health impacts. It has often been ineffective due to development of resistant insect populations. Thus, it has necessary to research new effective and less impacting control forms. In this sense, the use of entomopathogenic nematodes and plant extracts has been effective for controlling this pest. However, studies are needed to assess the compatibility between these methods, aiming at their use in integrated management programs for this pest. The aim of this study was to evaluate the compatibility of the nematodes Steinernema carpocapsae ALL and Heterorhabditis sp. JPM4 with aqueous extracts prepared from dried plant of cinnamon leaf, twig and fruit (Melia azedarach), rue leaf (Ruta graveolens), ginger (Zingiber officinale) and garlic (Allium sativum) for the control of C. capitata. The bioassay was carried out in completely randomized design with four replicates per treatment. Each replication consisted of a glass tube containing 1 mL of plant extract 40% w/v and 1 mL suspension of entomopathogenic nematodes with 1800 JI/mL for S. carpocapsae ALL and 600 JI/mL for Heterorhabditis sp. JPM4. The viability and infectivity of this nematode were evaluated on C. capitata larvae after 48 and 120 hours. It was found that all extracts reduced the viability and infectivity of both nematodes and they were incompatible after 120 hours of exposure. The nematode Heterorhabditis sp. JPM4 was more sensitive than the S. carpocapsae ALL as it showed, in the first 48 hours, a reduction in the viability and infectivity of more than 80 and 75%, respectively, when exposed to all the extracts except the ginger.

Compatibilidade de nematóides entomopatogênicos e extratos vegetais aquosos visando o controle da mosca-das-frutas Ceratitis capitata (Wiedemann) (Diptera: Tephritidae)

Currently, the fruit fly Ceratitis capitata (Diptera: Tephritidae) has been controlled mainly by the chemical method, which is responsible for environmental and public health impacts. It has often been ineffective due to development of resistant insect populations. Thus, it has necessary to research new effective and less impacting control forms. In this sense, the use of entomopathogenic nematodes and plant extracts has been effective for controlling this pest. However, studies are needed to assess the compatibility between these methods, aiming at their use in integrated management programs for this pest. The aim of this study was to evaluate the compatibility of the nematodes Steinernema carpocapsae ALL and Heterorhabditis sp. JPM4 with aqueous extracts prepared from dried plant of cinnamon leaf, twig and fruit (Melia azedarach), rue leaf (Ruta graveolens), ginger (Zingiber officinale) and garlic (Allium sativum) for the control of C. capitata. The bioassay was carried out in completely randomized design with four replicates per treatment. Each replication consisted of a glass tube containing 1 mL of plant extract 40% w/v and 1 mL suspension of entomopathogenic nematodes with 1800 JI/mL for S. carpocapsae ALL and 600 JI/mL for Heterorhabditis sp. JPM4. The viability and infectivity of this nematode were evaluated on C. capitata larvae after 48 and 120 hours. It was found that all extracts reduced the viability and infectivity of both nematodes and they were incompatible after 120 hours of exposure. The nematode Heterorhabditis sp. JPM4 was more sensitive than the S. carpocapsae ALL as it showed, in the first 48 hours, a reduction in the viability and infectivity of more than 80 and 75%, respectively, when exposed to all the extracts except the ginger.