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Abundance of plastic waste has become threat to the mankind and aquatic life and thus needs to be recycled or converted into value added products. Liquefaction of waste plastics via catalytic cracking is one the efficient routes towards plastic waste management. Concerning this, in present study, conversion of polymer mixture containing polypropylene, low-density polyethylene and high-density polyethylene (PP, LDPE and HDPE) was done for the production of gasoline and diesel range hydrocarbons using two-step cracking approach. MWW and MFI (12 and 10 member ring structures respectively) type zeolites having different pore structure and acidity were used for catalytic cracking of polymer feed at 350 °C. Investigations revealed that MWW type zeolite having two independent pore channels selectively provides gasoline range of hydrocarbons (C7-C12, 99.12%) in polymer cracking reaction as compared to MFI type which results in C13-C20 range of hydrocarbons (73.19%). Hydrocarbon compositions were confirmed from GC-MS, 1H, 13C NMR and FT-IR techniques. In activity results it was observed that acidity of zeolites affects the liquid yield and hydrocarbon distribution as analysed by using zeolites of two different SiO2/Al2O3 (SAR) ratio (30 and 55) which directs that zeolite (MFI/MWW) with lower SAR (30) having higher acidity results in higher yield of fuel range liquid hydrocarbons as compared to higher SAR (55) zeolite. Characterization studies such as XRD, N2-physisorption, NH3-TPD, FE-SEM and EDX were performed to check the physiochemical properties of zeolite and correlated with the activity. Overall, the present investigation provides detailed comparative study on plastic degradation using MFI and MWW type zeolites resulting into different range of liquid hydrocarbons.
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Zeolitas , Catálisis , Hidrocarburos , Plásticos , Dióxido de Silicio , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In this study, urease mediated calcite precipitation technique was used for remediation of Zn (II). A urease positive Enterobacter cloacae EMB19 was used to produce calcite impregnated with Zn ions. In co-presence of Ca (II), Zn (II) concentrations of 10 and 20 mg L-1 were completely remediated by the bacterium from the media at 72 and 96 h of incubation, respectively. Co-precipitation of Ca (II) and Zn (II) to form calcite-Zn precipitate is one of the major mechanisms of Zn remediation in the present study. Role of urease in calcite-Zn precipitation was substantiated by using urease/carbonate and ammonium enriched cell free culture supernatant (CFS) obtained after sufficient microbial growth. Using CFS, 68% removal of initial 50 mg L-1 Zn (II) was detected. Energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction pattern (XRD) of the precipitate supports calcite mediated remediation of Zn. Remediation of multiple metals viz. Cd, Zn, Cu was also analyzed using CFS laden with urease. The preparation showed 40% Cd, 23% Zn, and 8% Cu reduction from the solution containing initial 25 mg L-1 of each metal. Overall, it can be concluded that, the E. cloacae mediated calcite precipitation technique could effectively be used for alleviation of Zn (II) and other heavy metals from the contaminated environment.
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Carbonato de Calcio/química , Enterobacter cloacae/enzimología , Ureasa/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Zinc/análisis , Amoníaco/química , Carbonatos/química , Precipitación Química , Restauración y Remediación AmbientalRESUMEN
Two climate metrics, Global surface Temperature Change Potential (GTP) and the Absolute GTP (AGTP) are used for studying the global surface temperature impact of CH4 emission from livestock in India. The impact on global surface temperature is estimated for 20 and 100 year time frames due to CH4 emission. The results show that the CH4 emission from livestock, worked out to 15.3 Tg in 2012. In terms of climate metrics GTP of livestock-related CH4 emission in India in 2012 were 1030 Tg CO2e (GTP20) and 62 Tg CO2e (GTP100) at the 20 and 100 year time horizon, respectively. The study also illustrates that livestock-related CH4 emissions in India can cause a surface temperature increase of up to 0.7mK and 0.036mK over the 20 and 100 year time periods, respectively. The surface temperature response to a year of Indian livestock emission peaks at 0.9mK in the year 2021 (9 years after the time of emission). The AGTP gives important information in terms of temperature change due to annual CH4 emissions, which is useful when comparing policies that address multiple gases.
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Contaminantes Atmosféricos/análisis , Cambio Climático , Ganado , Metano/análisis , Modelos Teóricos , Temperatura , Animales , IndiaRESUMEN
In the present study, urease positive Serratia marcescens (NCIM2919) and Enterobacter cloacae EMB19 (MTCC10649) were individually evaluated for remediation of cadmium (II) using ureolysis-induced calcium carbonate precipitation. Both the cultures were observed to efficiently remove cadmium from the media through co-precipitation of Cd (II) and Ca (II). S. marcescens and E. cloacae EMB19, respectively showed 96 and 98% removal of initial 5.0â¯mgâ¯L-1 soluble Cd (II) from the urea and CaCl2 laden media at 96â¯h of incubation period. At higher Cd (II) concentrations of 10 and 15â¯mgâ¯L-1, cadmium removal efficiency was much higher in case of E. cloacae EMB19 compared to S. marcescens. In-vitro cadmium (II) remediation study using urease containing cell-free culture supernatant of S. marcescens and E. cloacae EMB19 showed respective 98 and 53% removal of initial 50â¯mgâ¯L-1â¯Cd (II) from the reaction mixtures in co-presence of Ca (II). While in sole presence of Cd (II), only 16 and 8% removal of Cd (II) were detected for S. marcescens and E. cloacae EMB19, respectively. The elemental analysis of the co-precipitated mineral products using Energy Dispersive X-ray spectroscopy (EDX) clearly showed the prevalence of Ca and Cd ions. The morphology Cd-Ca composites formed with respect to both the cultures were observed to be of different shape and size as revealed through Scanning Electron Microscopy (SEM). Entire study hence comes out with a sustainable bioremediation option which could be effectively used to tackle Cd (II) or other heavy metal pollution.
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Cadmio/aislamiento & purificación , Enterobacter cloacae/enzimología , Serratia marcescens/enzimología , Ureasa/metabolismo , Cadmio/química , Contaminantes Ambientales/química , Contaminantes Ambientales/aislamiento & purificación , Metales PesadosRESUMEN
Rheological characteristics of Desi ghee were investigated at 18, 24, 30 and 36 °C. The steady shear properties were evaluated by varying the shear rate from 0.01 to 100 s-1 and the dynamic shear properties were studied by varying strain and frequency sweep from 0.01 to 100% and 0.1 to 100 rad s-1, respectively. At the four selected temperatures, the ghee samples displayed non-Newtonian shear thinning behavior with flow behavior index (n) ranging from 0.224 to 0.911. As the shear rate increased from 0 to 100 s-1, the values of dynamic viscosity decreased from 54 to 8.14, 20.01 to 1.05, 1.33 to 0.295, and 3.02 to 0.0025 Pa s at 18, 24, 30 and 36 °C, respectively. Out of four rheological models (Power-law or Ostwald-de Waele, Herschel-Bulkley, Casson, and Bingham model) fitted to the shear rate and stress data, the Ostwald model was found to be superior in predicting the shear rate-stress data at 18 °C, whereas Ostwald-de Waele and Herschel-Bulkley models predicted all the data points over the temperature range of 24-30 °C, as observed by the values of coefficient of determination (R2 ), standard deviation (SD), and relative deviation percentage (Rd ). The value of activation energy (EA ), as calculated from Arrhenius type equation, was found to be 1.98 × 106 kJ mol-1 over the entire temperature range. The study also revealed that the magnitudes of dynamic shear viscosity (η*) were higher than those of the steady shear viscosity (η) at the four temperatures, indicating that the Cox-Merz rule was not applicable to the ghee samples.
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In present study, in vitro nematocidal bioassays, FT-IR and HPLC analysis were employed to demonstrate the involvement of toxins of Purpureocillium lilacinum in killing root-knot nematodes (Meloidogyne incognita). During growth study, maximum mycelial biomass (10.52 g/l) in de-oiled Karanja cake medium was achieved on 8th day while complete mortality of nematodes was obtained by 6th day filtrate (FKSM). Maximum production of crude nematocidal toxin was recorded on 7th day suggesting that the toxin production was paralleled with growth of the fungus. The median lethal concentration (LC50) determined for the crude toxin from 6th day to 10th day ranged from 89.41 to 43.21 ppm. The median lethal time (LT50) for the crude toxin of FKSM was found to be 1.46 h. This is the first report of implementing a comparative infra-red spectroscopy coupled with HPLC analysis to predict the presence of nematocidal toxin in the fungal filtrate cultured on Karanja deoiled cake liquid medium.
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Antinematodos/metabolismo , Antinematodos/toxicidad , Medios de Cultivo/toxicidad , Hypocreales/química , Pongamia/microbiología , Animales , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Hypocreales/crecimiento & desarrollo , Hypocreales/metabolismo , Dosificación Letal Mediana , Pongamia/metabolismo , Tylenchoidea/efectos de los fármacosRESUMEN
Bamboos, a group of large woody grasses belonging to the family Poaceae and subfamily Bambusoideae, are much talked about for their contribution to the environment. However, the food potential of Bamboo shoot per se remains unexploited. Literature on the nutritional and medicinal potential of bamboo shoots is scarce. This paper therefore provides insight on bamboo shoot as a food resource. Various edible species and exotic food products (fermented shoots, pickle, etc.) and recipes of bamboo shoots (bamboo beer, bamboo cookies) are consumed worldwide. Change in nutritional composition of different species of bamboo shoots with processing has also been reviewed. Bamboo shoots possess high protein, moderate fiber, and less fat content. They are also endowed for having essential amino acids, selenium, a potent antioxidant, and potassium, a healthy heart mineral. Occurrence of taxiphyllin, a cyanogenic glycoside in raw shoots, and its side effect on human health calls for the demand to innovate processing ways using scientific input to eliminate the toxic compound without disturbing the nutrient reserve. Lastly, the paper also reviews the utilization of medicinal properties acquired by bamboo shoot. Using the traditional knowledge, pharmaceutical preparations of bamboo shoots like bamboo salt, bamboo vinegar, bamboo extracts for diabetes and cholesterol control, etc. are now gaining importance. Further investigation is required by the researchers to make novel nutraceutical products and benefit the society.
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Bambusa/química , Bebidas/análisis , Valor Nutritivo , Preparaciones de Plantas/análisis , Brotes de la Planta/química , Seguridad de Productos para el Consumidor , Fermentación , Manipulación de Alimentos/métodos , Glicósidos/análisis , Glicósidos/toxicidad , Humanos , Nitrilos/análisis , Nitrilos/toxicidad , Preparaciones de Plantas/administración & dosificación , Preparaciones de Plantas/efectos adversosRESUMEN
Bamboo shoot as food has been used in traditional ways by the tribal community the world over. For enhancing its business potential, research on various aspects of bamboo shoot as food is being carried out in Japan, Taiwan, Thailand, and Asian countries and several products are available in the market. Bamboo shoots are used as a delicacy in human food, are a good source of dietary fiber, low in fat and calories. The research studies included in this review paper focus on post-harvest preservation of bamboo shoot. In view of the seasonal availability of bamboo shoot, the post-harvest preservation system for handling cynogenic toxicity in raw shoot while keeping nutrients intact and enhancement of shelf life of the value added products assume great significance for the business potential of this natural product. A yardstick of assessing the "Shelf life-Quality Matrix" developed in this review paper would give a new perspective of quality control in case of preservation of bamboo shoot. Also, knowledge gaps identified in this paper would give impetus to new academic and R&D activities, in turn generating an innovative job profile in the food industry as well as rural entrepreneurship.
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Bambusa/química , Conservación de Alimentos/métodos , Brotes de la Planta/química , Pueblo Asiatico , Bambusa/efectos adversos , Bambusa/microbiología , Emprendimiento/economía , Contaminación de Alimentos/prevención & control , Embalaje de Alimentos , Conservación de Alimentos/economía , Conservación de Alimentos/instrumentación , Almacenamiento de Alimentos , Alimentos en Conserva/efectos adversos , Alimentos en Conserva/análisis , Alimentos en Conserva/economía , Alimentos en Conserva/microbiología , Glicósidos/análisis , Humanos , Nitrilos/análisis , Valor Nutritivo , Brotes de la Planta/efectos adversos , Brotes de la Planta/microbiología , Control de CalidadRESUMEN
BACKGROUND: Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti-nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio-diesel and glycerol). RESULTS: The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg⻹) than in expeller oil (2.1 g kg⻹). Liquid chromatography-mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg⻹) than in cake after being expelled (0.8 g kg⻹). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg⻹ and 8347 TIU g⻹ of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L⻹ of crude concentrate obtained from cake. CONCLUSION: Higher amounts of phorbol esters are present in oil than cake but bio-diesel and glycerol are free of phorbol esters. The other anti-nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed.
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Biocombustibles/análisis , Glicerol/química , Residuos Industriales/análisis , Jatropha/química , Fitoquímicos/análisis , Aceites de Plantas/química , Semillas/química , Agricultura/economía , Alimentación Animal/análisis , Alimentación Animal/economía , Biocombustibles/economía , Ácidos Grasos/análisis , Contaminación de Alimentos , Glicerol/economía , Glicerol/aislamiento & purificación , India , Residuos Industriales/economía , Ésteres del Forbol/análisis , Ésteres del Forbol/economía , Ésteres del Forbol/aislamiento & purificación , Ácido Fítico/análisis , Ácido Fítico/economía , Ácido Fítico/aislamiento & purificación , Fitoquímicos/economía , Fitoquímicos/aislamiento & purificación , Aceites de Plantas/economía , Aceites de Plantas/aislamiento & purificación , Proteínas Inactivadoras de Ribosomas Tipo 1/análisis , Proteínas Inactivadoras de Ribosomas Tipo 1/economía , Proteínas Inactivadoras de Ribosomas Tipo 1/aislamiento & purificación , Inhibidores de Tripsina/análisis , Inhibidores de Tripsina/economía , Inhibidores de Tripsina/aislamiento & purificaciónRESUMEN
The heterogeneous nature of e-waste, which is a rich source of metals, polymers, glass fibres and ceramics, is troublesome. Multi-step processes are employed to effectively treat e-waste with minimum environmental impact. In this research, a subcritical to supercritical methanol environment was investigated to pre-treat e-waste, recovering non-metallic fractions and eventually concentrate metals from e-waste. Experiments were conducted in the temperature range of 150 °C to 300 °C at an autogenous pressure with initial atmospheric pressure. The mechanism of depolymerization was investigated by varying reaction time from 30 min to 240 min; solid to liquid ratio of 1:10 to 1:30 g/ml in a batch reactor under N2 environment. Comparative analysis of liquid products obtained after Supercritical Methanol (SCM) treatment for both Waste Random Access Memory (WRAM) and Waste Printed Circuit Board (WPCB) was done with pyrolyzed oil/liquid product. This research briefly illustrates oil and solid product compositional changes with operating temperature, pressure, and solid/liquid ratio range. The metal concentrations of copper, nickel, silver, zinc, and gold are greater than 90% after SCM treatment. For comparison, the feed material was pyrolyzed under the same condition, the difference in oil and solid products are assessed. In the end section, the environmental and economic benefits of SCM were also discussed compared to other supercritical and conventional technologies. An efficient and greener approach of supercritical solvent is proposed via this research for e-waste recycling.
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Residuos Electrónicos , Cobre/análisis , Residuos Electrónicos/análisis , Metanol , Reciclaje , Plata/análisisRESUMEN
Plastic waste is a serious menace to the world due to its fastest growth rate of ~ 5% per annum and requires efficient technologies for its safe disposal. Plastic liquefaction producing liquid hydrocarbons is an effective way to dispose waste plastics in an eco-friendly manner. In present study, high quality liquid fuel is produced from waste plastics via two-step bottom-up cracking approach. A comparative analysis of liquid products obtained in thermal and catalytic cracking performed at relatively lower temperature (350 °C) with minimal catalyst to plastic feed ratio (1:30) has been studied. Catalytic cracking via two-step bottom-up route provides higher fraction of fuel range hydrocarbons in comparison to the thermal cracking. Catalytic cracking is performed using two different catalysts; HZSM-5 and 5%Fe/HZSM-5 in which later results in higher liquid yield (76 wt%) than former (60 wt%) having comparable fuel characteristics. GC-MS results confirm that liquid product obtained via catalytic cracking contains higher fraction of fuel range hydrocarbons (C6-C20); 66.39% for 5%Fe/HZSM-5 and 47.33% for HZSM-5 which is comparatively higher than that obtained in thermal cracking (27.39%). FT-IR, 1H and 13C NMR spectroscopic studies confirm that liquid hydrocarbons obtained via catalytic cracking have comparable chemical characteristics with fuel range hydrocarbons. Physiochemical properties of catalysts are studied using XRD, XPS, BET, FE-SEM, HR-TEM, NH3-TPD and H2-TPR techniques and correlated with activity results. Analysis of commercial diesel fuel is also incorporated to compare the fuel characteristics of liquid products.
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Hidrocarburos , Plásticos , Catálisis , Gasolina , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Bamboo shoot fermentation is a traditional process carried out in different communities of the North-Eastern region. To understand the mechanism involved in the traditional process, its scientific validation was done in laboratory. The shoots were fermented for a period of 30 days with the addition of inoculum. Initial investigation showed that the acidity increased and cyanogenic toxicity decreased. The final fermented bamboo shoot product was further analyzed for the proximate composition, minerals and antioxidant capacity. An increase in the protein content (+17.28%) was found in the fermented sample while fat and vitamin C were found to decrease i.e. 90.2% and 35.77% respectively. A significant increase in the phenol, flavonoid content and antioxidant capacity was also found to increase indicating their potential to protect human health. Bamboo shoot serves a great means to food security and a source of functional food. Commercializing fermented shoot products will preserve traditional knowledge and provide livelihood and achieve development goals.
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PURPOSE: Children are often afraid to visit a dentist. Dental anxiety is a worldwide issue and a barrier to successful treatment outcome. Pet therapy, especially through dogs, has been demonstrated to be beneficial in reducing anxiety. In today's generation, where dopamine is prevalent, attention is hijacked, and children are tethered to screens-this research on animal-assisted therapy outlines the impact on children undergoing simple dental procedures, and to evaluate its use in long-term behavior management, and child and parental acceptance of this technique. METHODS: One hundred and two children between five and 10 years of age and requiring simple dental procedures were selected randomly and divided into two groups. In Group A, dental treatment was carried out in the presence of a therapy dog, and in Group B (the control group), dental treatment was carried out in a regular dental setup. Anxiety levels were evaluated by pulse rate and anxiety rating scale. Prior to exiting the room, the parents were asked to rate the child's interaction with therapy dogs. RESULTS: According to an independent t test, reduction in anxiety was highly significant (p < 0.001). CONCLUSION: Animal-assisted therapy is an effective behavior management strategy.
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Terapia Asistida por Animales , Ansiedad al Tratamiento Odontológico , Animales , Niño , Conducta Infantil , Ansiedad al Tratamiento Odontológico/prevención & control , Humanos , Padres , Animales para TerapiaRESUMEN
In this study, the potential of heat desiccated milk powder (HDMP) in a composite dairy matrix with semi skimmed milk powder (SSMP) was assessed for hot melt extrusion-based 3D printing. The rheological characteristics of formulations at three stages i.e., pre-printing, printing, and post-printing were investigated. The shear thinning with rapid shear recovery and thermoresponsive behavior of the formulations were analyzed to mimic the prevailing conditions of pre-processing, processing, and post-processing of formulations to understand the temperature induced variations in their rheological characteristics during each stage. The rheological properties were correlated with printability through assessment of the consistency of straight lines (1D), average area of lattice scaffolds (2D), and dimensional stability of the 3D printed constructs. Results demonstrated that an increase in the level of incorporation of SSMP and a decrease in the proportion of HDMP increased the shear thinning behavior, viscosity (ɳ), yield stress (τ0), storage modulus (G') and a decline in the shear recoverability of the formulations. The thermoresponsive behavior of the formulations was established with gelation temperature ranging from 28.1 to 29.4ËC. The formulation SSMP (35): HDMP (25) resulted in sagging of the printed constructs, whereas the formulation SSMP (55): HDMP (5.0) exhibited the highest dimensional stability and shape retention post printing, owing to its maximum τ0 (1211.8 Pa) and G' (7026.4 Pa). The results obtained could provide insight into improving the performance of an HME based 3D printing in the dairy and food industries.
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Calor , Impresión Tridimensional , Reología , Temperatura , ViscosidadRESUMEN
A volatile alkaloid quinoline-4-carbonitrile (QCN) was isolated from the floral extract of Quisqualis indica. Major compounds were trans-linalool oxide (1.0, 4.5%), methyl benzoate (1.0, 4.0%), 2,2,6-trimethyl-6-vinyl-tetrahydropyran-3-one (7.4, 17.8%), 2,2,6-trimethyl-6-vinyl-tetrahydropyran-3-ol (1.0, 1.2%), (E,E)-α-farnesene (29.1, 16.1%), QCN (5.7, 1.3%) in live and picked flowers, respectively. Flower compositions were altered due to change in enzymatic reaction at the time of picking. Some rearrangements of oxygenated terpenoids occurred in the process of hydrodistillation to obtain essential oil. Chemical synthesis of QCN and its selectively reduced products derived from QCN were prepared through green reaction process. The catalytic modification of QCN has produced quinoline-4-methylamine; the later compound has shown enhanced bio-activities. QCN and floral extract (absolute) have shown potential anti-inflammatory and antioxidant activities. Besides, floral absolute has shown significant anti-inflammatory and antioxidant activities due to improved QCN (19.7%) content to synergize amongst terpenoids and benzenoids as compared to the essential oil with 1.1% of QCN.
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Alcaloides/farmacología , Combretaceae/química , Flores/química , Extractos Vegetales/farmacología , Quinolinas/farmacología , Alcaloides/análisis , Antiinflamatorios/farmacología , Antioxidantes/análisis , Antioxidantes/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Extractos Vegetales/química , Espectroscopía de Protones por Resonancia Magnética , Reproducibilidad de los Resultados , Microextracción en Fase SólidaRESUMEN
The use pesticide is one of the indispensable means to combat mosquito borne diseases. However, the repeated use of synthetic pesticides has induced resistance in the vector pest along with undesirable impact on the environment. The biodegradability, non-persistent and user's safety are the root cause to prefer plant-derived pesticides to synthetic ones. The botanical based pesticides tend to degrade rapidly under the influence of several environmental factors. For the feasible application as pesticides, the plant products are formulated either as liquid or as purely solid. Despite well-established formulation technology in pesticide delivery, their handling trouble is being ignored. There is difficulty in liquid formulation of pesticide products, as they are prone to splashing and spillage, resulting in contamination, wastage and direct exposure to skin; whereas a solid formulation tends to produce dust. In the present work, cedarwood (Cedrus deodara) essential oil embedded pectin nanocapsules were produced. The nanocapsules were characterized according to their morphology, size, encapsulation efficiency and thermal stability. Furthermore, the nanocapsules were impregnated onto mini cotton tea bags to be employed as RTU (ready to use) formulation for treating the breeding sites of mosquitoes. The larvicidal activity of the bags treated with pectin-cedar wood nanocapsules was assessed against malaria vector, Anopheles culicifacies and 98% mortality was recorded till 4 weeks, this suggests its potential and hassle free applications in controlling mosquito vector.
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Anopheles/efectos de los fármacos , Insecticidas/farmacología , Malaria/prevención & control , Mosquitos Vectores/efectos de los fármacos , Aceites Volátiles/farmacología , Animales , Agentes de Control Biológico/farmacología , Cedrus/química , Nanocápsulas , Pectinas , Té/químicaRESUMEN
Chitosan nanocapsules, containing lemongrass (Cymbopogon citratus) oil (LGO), have been developed in gel form in which acrylate (Ac) was incorporated as a thickener and fabric binder. The gel was impregnated on fabric to achieve long-lasting and wash-durable mosquito repellency. The interaction between cotton fibers and gel was investigated by FTIR and XRD. Wash durability of gel was compared with chitosan nanocapsules without acrylate (LGO-encap) using SEM and GC-MS. The SEM analyses revealed that acrylate containing nanocapsules retains on fabric after a series of washing. The GC-MS results indicated that the relative amount of deducible oil components from fabric was found to be higher after the series of washing in acrylate containing nanocapsules (LGO-encap-Ac), which further points to the improved wash durability and retention of capsules on fabric. The bio-efficacy results of post-fifteen washing turned out was 75% of repellency against mosquitoes with the use of acrylate; while in nanocapsules without acrylate, only 51% of repellency was achieved. Furthermore, the 36 days repeated application of nanogel on Swiss albino mice did not show any signs of dermal toxicity. The formulation is, thus, suitable to impregnate dress of the military personals and individuals who have to perform field duty and where risk of mosquito bites is probably more.
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Acrilatos/farmacología , Quitosano/farmacología , Culicidae/efectos de los fármacos , Polietilenglicoles/farmacología , Polietileneimina/farmacología , Piel/efectos de los fármacos , Acrilatos/química , Animales , Quitosano/química , Fibra de Algodón , Femenino , Ratones , Nanogeles/química , Tamaño de la Partícula , Polietilenglicoles/química , Polietileneimina/química , Propiedades de SuperficieRESUMEN
BACKGROUND & OBJECTIVES: In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal potential of the essential oil from the seeds of Zanthoxylum armatum DC [syn. Z. alatum Roxb] (Rutaceae) against three medically important species of mosquito vectors, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. METHODS: Essential oil was hydro distilled in the laboratory from the seeds obtained from the market and the chemical constituents of the oil were determined using GC/GC-MS. Bioefficacy of the essential oil was evaluated under laboratory conditions using III instar mosquito larvae. RESULTS: Among the three mosquito species tested, Cx. quinquefasciatus was the most sensitive (LC50 = 49 ppm) followed by Ae. aegypti (LC50 = 54 ppm) and An. stephensi (LC50 = 58 ppm). GC-MS analysis of the oil revealed at least 28 compounds, consisting mainly of oxygenated monoterpenes (75%) and monoterpenes (22%). Linalool though constituted a major part (57%), failed to produce any appreciable mortality when tested alone. INTERPRETATION & CONCLUSION: From the results it can be concluded that the larvae of the three mosquito species were susceptible to the essential oil composition. Such findings would be useful in promoting research aiming at the development of new agent for mosquito control based on bioactive chemical compounds from indigenous plant sources as an alternative to chemical larvicides.
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Culicidae/efectos de los fármacos , Insecticidas/farmacología , Control de Mosquitos/métodos , Aceites Volátiles/farmacología , Zanthoxylum/química , Aedes , Animales , Anopheles , Culex , Culicidae/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Insectos Vectores/efectos de los fármacos , Aceites Volátiles/análisis , Control Biológico de Vectores , Especificidad de la Especie , Resultado del TratamientoRESUMEN
Studies were carried out on transesterification of Karanja oil with methanol for the production of biodiesel. The reaction parameters such as catalyst concentration, alcohol/oil molar ratio, temperature, and rate of mixing were optimized for production of Karanja oil methyl ester (KOME). The fatty acid methyl esters content in the reaction mixture were quantified by HPLC and 1H NMR method. The yield of methyl esters from Karanja oil under the optimal condition was 97-98%.
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Millettia/metabolismo , Biotecnología/métodos , Catálisis , Cromatografía Líquida de Alta Presión , Fuentes Generadoras de Energía , Esterificación , Ésteres , Hidróxidos , Espectroscopía de Resonancia Magnética , Metanol/química , Aceites de Plantas/metabolismo , Compuestos de Potasio , TemperaturaRESUMEN
Larvicidal activity of Tagetes patula essential oil was tested against the fourth instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefaciatus. Five different concentrations of essential oil were studied and the results were compared with that of synthetic insecticide, malathion. A. aegypti (LC(50) 13.57, LC(90) 37.91) was most susceptible followed by An. stephensi (LC(50) 12.08, LC(90) 57.62) and C. quinquefaciatus (LC(50) 22.33, LC(90) 71.89).