Immobilizing engineered Escherichia coli cells into zeolitic imidazolate framework 8 for efficient biosynthesis of Ala-Gln / 生物工程学报

The α-amino acid ester acyltransferase (SAET) from Sphingobacterium siyangensis is one of the enzymes with the highest catalytic ability for the biosynthesis of l-alanyl-l-glutamine (Ala-Gln) with unprotected l-alanine methylester and l-glutamine. To improve the catalytic performance of SAET, a one-step method was used to rapidly prepare the immobilized cells (SAET@ZIF-8) in the aqueous system. The engineered Escherichia coli (E. coli) expressing SAET was encapsulated into the imidazole framework structure of metal organic zeolite (ZIF-8). Subsequently, the obtained SAET@ZIF-8 was characterized, and the catalytic activity, reusability and storage stability were also investigated. Results showed that the morphology of the prepared SAET@ZIF-8 nanoparticles was basically the same as that of the standard ZIF-8 materials reported in literature, and the introduction of cells did not significantly change the morphology of ZIF-8. After repeated use for 7 times, SAET@ZIF-8 could still retain 67% of the initial catalytic activity. Maintained at room temperature for 4 days, 50% of the original catalytic activity of SAET@ZIF-8 could be retained, indicating that SAET@ZIF-8 has good stability for reuse and storage. When used in the biosynthesis of Ala-Gln, the final concentration of Ala-Gln reached 62.83 mmol/L (13.65 g/L) after 30 min, the yield reached 0.455 g/(L·min), and the conversion rate relative to glutamine was 62.83%. All these results suggested that the preparation of SAET@ZIF-8 is an efficient strategy for the biosynthesis of Ala-Gln.

Nanocompósitos magnéticos para concentração/remoção de contaminantes de águas / Magnetic adsorbent nanocomposites for water treatment

Zeólitas e carvão ativado são materiais eficazes para o tratamento de efluentes devido a sua grande área superficial e possibilidades de funcionalização, que permitem o desenvolvimento de novos materiais derivados visando a processos de concentração/remoção de contaminantes, por exemplo, em águas. A preparação de nanocompósitos magnéticos e sua aplicação na remoção seletiva de poluentes em meio aquoso tornou-se viável devido as interações distintas que ocorrem entre zeólita e carvão ativado com compostos orgânicos, íons metálicos e compostos nitrogenados. Assim, novos materiais voltados para sistemas de tratamento de águas residuais e monitoramento ambiental foram desenvolvidos com base em materiais bem estabelecidos. Os nanocompósitos foram caracterizados estrutural e morfologicamente por técnicas de microscopia eletrônica de varredura, termogravimetria, espectroscopia no infravermelho, espalhamento de luz, difração de raios x, bem como suas capacidades de adsorção. Foi avaliado também a viabilidade de aplicações em métodos analíticos, como pré-concentração por extração em fase sólida magnética (M-SPE), e, para tratamento de efluentes em amostras reais. Contaminação por cromo (VI), outras espécies potencialmente tóxicas e amônio foram removidos de águas residuais, gerando produtos tratados com níveis de contaminantes suficientemente baixos para atenderem as recomendações da EPA (Environmental Protection Agency) e CONAMA (Conselho Nacional do Meio Ambiente), permitindo seu descarte na natureza. Os materiais demonstraram ser adequados para pré-concentração rápida, eficiente, economicamente competitiva e ambientalmente amigável de amostras por M-SPE para quantificação analítica de espécies orgânicas ou inorgânicas, por técnicas analíticas convencionais. Assim, foi demonstrado a possibilidade de determinação simultânea de elementos potencialmente tóxicos e de outros cátions metálicos em concentrações traço (ppb), diretamente no material compósito magnético, por espectroscopia de fluorescência de raios X de energia dispersiva (EDX), além da quantificação de traços de compostos orgânicos semi-voláteis por cromatografia emfase gasosa com detector por espectrometria de massas, aumentando a sensibilidade para além do limite nominal de detecção por essas técnicas

Zeolites and activated carbon are effective materials for the treatment of effluents due to their large surface area and functionalisation possibilities, which allow the development of new derived materials aiming at the concentration/removal of contaminants from water, for example. The preparation of magnetic nanocomposites and their application in the selective removal of pollutants in aqueous media has become feasible due to the distinct interactions that occur between zeolite and activated carbon with organic compounds, metal ions and nitrogen compounds. Thus, new materials for wastewater treatment and environmental monitoring systems were developed based on well-established materials. The nanocomposites were structural and morphologically characterized by scanning electron microscopy, thermogravimetry, infrared spectroscopy, light scattering, x-ray diffraction, as well as their adsorption capacities, viability of applications in analytical methods such as preconcentration by extraction in magnetic solid phase, M-SPE, were evaluated, and the composite materials Cmag and Zmag applied for treatment of real samples. Chromium (VI) contamination, heavy metal cations and ammonium were removed from wastewater, generating treated products with levels of contaminants low enough to meet the EPA and CONAMA recommendations, allowing their disposal in the wild. The materials have been shown to be suitable for rapid, efficient, economically competitive and environmentally friendly preconcentration of samples per M-SPE for analytical quantification of organic or inorganic species by conventional analytical techniques. Thus, it was demonstrated the possibility of simultaneous analysis of heavy metals and other metal cations in trace concentrations (ppb), directly in the magnetic composite material, by dispersive energy X-ray fluorescence spectroscopy (EDX), in addition to the quantification of traces of volatile organic compounds (VOC) by gas chromatography with mass spectrometry detector, increasing the sensitivity beyond the nominal limit of detection by these techniques

Avaliação da forma de inclusão de zeólita e do nível de consumo sobre a digestibilidade da dieta e as características fecais de cães / Evaluation of zeolite inclusion and level of food intake on diet digestibility and faecal characteristics of dogs

Objetivou-se avaliar a forma de inclusão da zeólita e de níveis de consumo sobre a digestibilidade da dieta e as características fecais de cães. O experimento 1 avaliou o efeito do nível de consumo (normal e 50% a mais do que as necessidades) e da inclusão de zeólita (0 e 15g/kg) sobre a digestibilidade e as características fecais de 12 cães. No experimento 2, foi avaliada a inclusão de 5, 15 e 25g/kg de zeólita adicionada na massa ou por cobertura, em seis cães, sobre a digestibilidade da dieta e as características fecais. O experimento 3 avaliou o odor fecal de nove cães consumindo dietas contendo 0 e 15g/kg de zeólita incluída na massa ou por cobertura. A quantidade consumida e a inclusão de zeólita não afetaram a digestibilidade das dietas. O escore e a matéria seca fecal aumentaram com a inclusão de zeólita. A inclusão de zeólita na massa propiciou aumento na digestibilidade das dietas, independentemente do nível de inclusão. A inclusão de 15g/kg de zeólita, adicionada na massa e por cobertura reduziu o odor fecal dos cães. A inclusão de zeólita na massa aumenta a digestibilidade da dieta, a consistência fecal e reduz o odor fecal de cães.(AU)

This study aimed to evaluate the form of inclusion of zeolite and consumption levels on diet digestibility and fecal characteristics of dogs. The first experiment examined the effect of consumption level (normal and 50% higher than the requirements) and zeolite level (0 and 15g/kg) on diet digestibility and fecal characteristics of 12 dogs. In experiment 2 the inclusion of 5, 15 and 25g/kg of added zeolite in dough or coating in six dogs on diet digestibility and fecal characteristics was evaluated. The third experiment assessed the fecal odor of nine dogs fed diets containing 0 and 15g/kg of zeolite included in the dough or coating. The amount consumed, as well as the inclusion of zeolite, did not affect diet digestibility. Fecal score and dry matter increased with the inclusion of zeolite. The inclusion of zeolite in the dough provided an increase in diet digestibility, regardless of the level of inclusion. The inclusion of 15g/kg zeolite added to the dough and by coating reduced fecal odor of dogs. The inclusion of zeolite in dough increases diet digestibility, fecal consistency, and reduces the fecal odor of dogs.(AU)

Zeólitas naturais na dieta de frangos de corte / Natural zeolites in broiler diet

O objetivo deste trabalho foi avaliar o efeito da inclusão de 0,5% da zeólita natural clinoptilolita na dieta de frangos de corte sobre o consumo de água, ração e características das excretas. Foi conduzido um ensaio em gaiolas metabólicas, com frangos de corte de linhagem comercial, no período de 14 a 23 dias de idade. O experimento foi constituído de dois grupos de aves, sendo que um recebeu dieta sem inclusão de zeólitas (controle) e outro dieta com inclusão de 0,5% de zeólita (clinoptilolita) em rações isonutritivas, em um delineamento inteiramente ao acaso, com 10 repetições de 10 aves. Avaliou-se o consumo de água e de ração, nas excretas, pH, teor de nitrogênio total e umidade. A inclusão de 0,5% de zeólitas naturais na dieta não alterou (P>0,05) o consumo de água e de ração e o teor de nitrogênio das excretas, entretanto, reduziu (P<0,05) o pH e a umidade das excretas. Conclui-se que a inclusão de 0,5% de zeólitas naturais na dieta de frangos de corte reduz o pH e a umidade das excretas e pode ser utilizada como aditivo alimentar sem prejudicar o consumo de água e de ração.(AU)

The aim of this study was to evaluate the addition of 0.5% natural zeolites (clinoptilolite) to the diet of broilers and their effect on water and feed intake and excreta characteristics. The test was carried out in metabolic cages, with commercial line broilers, in the period from 14 to 23 days old. The experiment was conducted with two groups of broilers: one group received diet without zeolite inclusion (control) and the other received a diet with 0.5% inclusion of zeolite (clinoptilolite) in balanced diets, in a completely randomized design, with 10 replicates of 10 broilers. Water and feed intake, pH, total nitrogen, and moisture of excreta were evaluated. The inclusion of 0.5% of natural zeolites in the diet did not change (P>0.05) the water and feed intake and total nitrogen of excreta, nevertheless, it decreased (P<0.05) the pH and moisture of excreta. We conclude that the addition of 0.5% natural zeolites to the diet of broilers decreases pH and moisture of excreta and can be used as feed additive without compromising water and feed intake.(AU)

Effectiveness of thymoquinone, zeolite, and platelet-rich plasma in model of corrosive oesophagitis induced in rats

PURPOSE: The effectiveness of platelet-rich plasma (PRP), thymoquinone, and zeolite in corrosive esophageal burns was investigated in a rat model. METHODS: Four groups were comprised as containing 10 rats in each group. For group I, oesophagitis was induced and no other procedure was performed (control group). For group II, oesophagitis was induced and thymoquinone was administered for 1 week via oral gavage once a day (thymoquinone group). For group III, oesophagitis was induced for 1 week via oral gavage once a day (PRP group). For group IV, oesophagitis was induced and zeolite was administered for 1 week via oral gavage once a day (zeolite group). On the 10th day, the rats were sacrificed under anaesthesia and venous blood sampling was performed from the vena portae. The oesophaguses were totally excised. Biochemically, interleukin (IL)-1B, IL-6, TNF-α, and MCP-1 were examined from venous blood. Inflammation score was evaluated histopathologically in oesophageal tissue that was collected. RESULTS: There was a statistically significant difference among groups in terms of IL-1, IL-6, MCP levels, compared to the control group; median IL-1, IL-6, MCP levels of thymoquinone, PRP, and zeolite groups were statistically significantly lower. There was a statistically significant difference among groups in terms of inflammation scores, compared to group I; median inflammation scores of groups II, III and IV were statistically significantly lower thymoquinone. CONCLUSION: PRP, and zeolite exhibited positive effect on recovery in oesophagitis by reducing inflammation in the involved segment.

Clinical and Prognostic Features of Erionite-Induced Malignant Mesothelioma

This review analytically examines the published data for erionite-related malignant pleural mesothelioma (E-MPM) and any data to support a genetically predisposed mechanism to erionite fiber carcinogenesis. Adult patients of age > or =18 years with erionite-related pleural diseases and genetically predisposed mechanisms to erionite carcinogenesis were included, while exclusion criteria included asbestos- or tremolite-related pleural diseases. The search was limited to human studies though not limited to a specific timeframe. A total of 33 studies (31042 patients) including 22 retrospective studies, 6 prospective studies, and 5 case reports were reviewed. E-MPM developed in some subjects with high exposures to erionite, though not all. Chest CT was more reliable in detecting various pleural changes in E-MPM than chest X-ray, and pleural effusion was the most common finding in E-MPM cases, by both tests. Bronchoalveolar lavage remains a reliable and relatively less invasive technique. Chemotherapy with cisplatin and mitomycin can be administered either alone or following surgery. Erionite has been the culprit of numerous malignant mesothelioma cases in Europe and even in North America. Erionite has a higher degree of carcinogenicity with possible genetic transmission of erionite susceptibility in an autosomal dominant fashion. Therapeutic management for E-MPM remains very limited, and cure of the disease is extremely rare.

Efficacy of clinoptilolite supplementation on milk yield and somatic cell count / La eficacia de la suplementación con clinoptilolita sobre la producción de leche y el recuento de células somáticas

Objective. To determine the efficiency of clinoptilolite supplements on milk production and somatic cell count (SCC). Materials and methods. 80 Holstein-Friesian cows were used, between 2 and 4 years of age ad between their first and third lactation. Two groups made up of 40 animals were constituted, and one of the following treatments were assigned randomly: Control group (n=40) with a basal diet, and experimental group (Clinoptilolite; n=40) with a basal diet + 3% (p/p) of clinoptilolite. The basal diet consisted of corn, hay, sunflower flour, barley grains, wheat bran and soy flour. The experiment lasted 16 weeks (February to June 2013) and began 4 weeks before the expected delivery date. 2560 milk samples were taken (morning and evening), and the farm was visited twice a week. Results. The mean values for the control group and the clinoptilolite group were 30.63±0.851 and 33.66±0.756, respectively. Milk prouction for the clinoptilolite group was higher than that of the control group (p<0.01). SCC for the control and clinoptilolite groups was 5.06±0.045 and 4.79±0.011, respectively (p<0.01). Conclusions. Supplementing with 3% (p/p) clinoptilolite in dairy cows increases milk production and decreases somatic cell count.

Objetivo. Determinar la eficacia de la suplementación con clinoptilolita sobre la producción de leche y recuento de células somáticas (RCS). Materiales y métodos. Se utilizaron 80 vacas Holstein-Friesian, entre 2 y 4 años de edad y entre la primera y tercera lactancia. Se conformaron dos grupos de 40 animales y al azar se les asignó uno de los siguientes tratamientos: Grupo control (n=40) con dieta basal y un grupo experimental (Clinoptilolita; n=40) con dieta basal + 3% (p/p) de clinoptilolita. La dieta basal consistió de maíz, heno, harina de girasol, granos de cebada, salvado de trigo y harina de soja. El experimento se llevó a cabo en 16 semanas (febrero a junio de 2013) y se inició 4 semanas de la fecha esperada del parto. Se tomaron 2.560 muestras de ordeño de leche (mañana y tarde), las visitas a la granja fueron realizadas dos veces por semana. Resultados. Los valores medios para el grupo control y el grupo clinoptilolita fueron 30.63±0.851 y 33.66±0.756, respectivamente. La producción de leche para el grupo clinoptilolita fue mayor que en el grupo control (p<0.01). El RCS para los grupo control y clinoptilolita fue de 5.06±0.045 y 4.79±0.011, respectivamente (p<0.01). Conclusiones. La suplementación de 3% (p/p) de clinoptilolita en la dieta de vacas lecheras incrementa la producción de leche y disminuye el recuento de células somáticas.

Inclusion of Yucca schidigera and zeolite in dog feed: influence on mineral excretion / Inclusão de Yucca schidigera e zeólita em alimentos para cães: influência sobre a excreção de minerais

This study aimed to evaluate the effects of adding Yucca schidigera and zeolite (Clinoptilolite) to feed (super premium and standard) for adult dogs on the apparent indigestibility coefficient of minerals. In the first assessment, 21 dogs were used, with average weight of 12.5kg±1.46 in seven treatments in two periods (super premium diet referred to as control and control with the addition of 125, 250, 375ppm Yucca schidigera and 0.5%, 0.75% and 1.0% zeolite). The second assessment was conducted with standard feed, using 21 experimental plots distributed in three treatments (standard diet referred to as control and control with the addition of 375ppm of Yucca schidigera and 1.0% zeolite). The additives did not affect the acceptability of feed and fecal characteristics in both assessments (P>0.05). With the exception of calcium, no minerals were affected by the inclusion of additives (P>0.05) in the experiment with super premium feed. In the assessment with standard feed, calcium as phosphorus and magnesium presented decreased excretion (P<0.05) with the inclusion of additives. It is possible to conclude that the inclusion of additives in the tested concentrations may interfere with the excretion of some minerals in the diet.

Este trabalho teve como objetivo avaliar os efeitos da inclusão de Yucca schidigera e zeólita (Clinoptilolita) em alimentos (super premium e standard) para cães adultos sobre o coeficiente de indigestibilidade aparente de minerais. No primeiro ensaio, foram utilizados 21 cães, com peso médio de 12,5kg±1,46, distribuídos em sete tratamentos em dois períodos (dieta super premium denominada controle e controle com adição de 125, 250, 375ppm de Yucca schidigera e 0,5%, 0,75% e 1,0% de zeólita). O segundo foi realizado com um alimento standard, utilizando-se 21 parcelas experimentais distribuídas em três tratamentos (dieta standard denominada controle e controle com adição de 375ppm de Yucca schidigera e 1,0% de zeólita). Os aditivos não afetaram a aceitabilidade do alimento e as características fecais nos dois ensaios (P>0,05). Com exceção do cálcio, nenhum mineral sofreu interferência da inclusão dos aditivos (P>0,05) no experimento com alimento super premium. No ensaio com alimento standard, tanto cálcio quanto fósforo e magnésio apresentaram redução na excreção (P<0,05) com a inclusão dos aditivos. Pôde-se concluir que a inclusão dos aditivos nas concentrações testadas pode interferir na excreção de alguns minerais da dieta.

Research progress of novel porous hemostatic agents / 中国实验血液学杂志

The treatment of bleeding wound of solid visceral and the rescue of uncontrollable bleeding are still confronted with difficulties in surgery and first-aid field. Many researchers devote to study in the field of hemostasis, and the novel porous hemostatic agent is one of the hot spot of research about hemostasis. The review focuses on the hemostatic effect, properties, hemostatic mechanism, shortcoming and future trends of three novel porous hemostatic agents such as polysaccharides, zeolite and wollastonite.

Experimental investigation of adsorption of copper from aqueous solution using vermiculite and clinoptilolite

Considering the point that the existence of heavy metals in the wastewater are so dangerous for the environment and it would have many bad consequences for all the creatures including human beings, we must try out the ways that make us capable of adsorbing these heavy metals. In order to accomplish this goal we should use a method called adsorbing. In this study the adsorption of copper ions in hydrated copper nitrate [Cu [NO[3]][2], 3H[2]O] aqueous solution on natural zeolite [Clinoptilolite] and vermiculite was studied in batch reactors. The effect of temperature [25, 50, 75 °C], solution pH [1.00-5.5] and concentration effect on the traditionally defined adsorption isotherm in the adsorbate range 100-325 mg/L for clinoptilolite and 100- 650 mg/L for vermiculite on the removal of copper was studied. The results showed that an increase in pH increases the adsorptivity of vermiculite. Pseudo second order model best described the reaction rate. Batch adsorption experiments conducted at room temperature [25 +/- 1 °C] showed that the adsorption pattern followed the Langmuir and Freundlich isotherm models. Optimum conditions for adsorption were determined at pH 5.5, and vermiculite and clinoptilolite at a dose of 3g. The concentration of metal ions was measured by Atomic Absorption Spectrometer [AAS]. The results indicated that vermiculite and clinoptilolite are appropriate for adsorbing copper ions

[Effects of different levels of zeolite on plant growth and amount of gel production in Aloe vera L. under different irrigation]

Researchers' attention has been focused on Aloe vera for a long time due to the numerous medicinal effects of this plant and its application in various fields of food, cosmetic and hygienic industries. This study was conducted to evaluate the different levels of Zeolite and irrigation conditions on vegetative growth and quantitative and qualitative changes in plant gel. It is based on a factorial randomized complete block design with 4 levels of Zeolite in soil and 3 levels of irrigation, in 3 replications. After 5 months, morphological traits were measured. Also the amount of aloin in leaf and vitamin C in the gel were measured. The best results of morphological traits were obtained with 22 g Zeolite treatment in 5 kg pots of soil and 21 days irrigation. The highest amount of aloin was observed in 44 g Zeolite treatment in 5 kg pots of soil with 7 days irrigation. The highest amount of vitamin C was obtained in 44 g Zeolite treatment in 5 kg pots of soil with 14 days irrigation. The overall results showed that zeolite plays an important role in promoting growth and increasing secondary metabolites in plant Aloe vera under different irrigation

Denitrification via nitrite in a modified UASB reactor using Chilean zeolite as microbial support

The general objective of this study was to develop a highly efficient, economical and integrated technology for the removal of nitrogen compounds through denitrification via nitrite. To achieve this, a modified UASB reactor was designed, set-up and operated using Chilean zeolite as microbial support. The results were compared to a conventional UASB reactor used as control. The volume of each reactor was 2 L. The reactors operated with synthetic wastewater under the same operating conditions [with superficial velocities, v[s], of up to 1 m/h] in the first part of the experiment. Later, during the second part of the experiment, only the modified UASB was used, with v[s] of up to 5.5 m/h. In the first part of the experiment, a higher velocity of denitrification in the reactor with zeolite was obtained. Nitrogen removal at the end of this experimental set for both reactors, with a v[s] lower than 1 m/h, was 87%. In the second stage, the modified UASB reactor operated at v[s] of between 1.5 and 5.5 m/h. Here, it was observed that the removal of nitrite increased significantly. Specifically, at v[s] values of 2.5, 4.0 and 5.5 m/h, a value of the nitrogen loading rate [NLR] of 1.22 kg N-NO[2] [-]/m[3]/d was kept constant, achieving nitrogen removal efficiencies of 50%, 65% and 95.5% respectively. This last value proves how highly effective the modified UASB reactor is when operating with v[s] as high as 5.5 m/h

Removal of styrene from air by natural and modified zeolite

Changing the surface characteristics of raw materials has created new prospects for catalysts and adsorption technology. Natural and modified zeolite with trimethylchlorosilane [TMSCI] has been used to adsorb styrene. Dynamic adsorption tests were performed with a number of standard characterization techniques and zeolite particles were examined in three sizes: less than 1 mm, 1-2 mm, and 2-4 mm. The gas concentration was 20 ppm, 40 ppm, and 60 ppm. Three flow rates were tested in this study: 0.5 l/min, 0.75 l/min, and 1 l/min. The sorption of Styrene depended on the particle diameter size, gas flow rate, and inlet gas concentration. The optimum size for adsorption was less than 1 mm, the optimum flow rate was 0.5 l/min, and the optimum gas concentration was 20 ppm. The adsorption capacity decreased with increasing size, flow rate, and concentration of the pollutant. The adsorption by the surface-modified zeolite increased by as much as 100% compared with natural zeolite. Therefore, the surface-modified natural zeolite may be utilized for many adsorption applications. This study shows the importance of chemical surface modification and confirms similar findings of other studies

Yucca schidigera e zeólita em alimento para gatos adultos e seus efeitos na excreção de minerais / Yucca schidigera and zeolite in food for adult cats and its effects in mineral excretion

Avaliou-se efeito da inclusão de Yucca schidigera e zeólita (Clinoptilolita) em alimento comercial úmido para gatos sobre a aceitabilidade da dieta, produção fecal diária e porcentagem de águas nas fezes, e sobre o coeficiente de indigestibilidade aparente de cálcio, fósforo, magnésio, sódio, potásso, ferro e manganês. Foram utilizados 21 gatos adultos, sem raça definida, com quatro anos e meio de idade e peso médio de 3,56kg, distribuídos em sete tratamentos - dieta úmida denominada controle, e dietas controle com adição de 125, 250 e 375ppm de Yucca schidigera e 0,5 por cento, 0,75 por cento e 1,0 por cento de zeólita - em delineamento inteiramente ao acaso. Não foram observadas diferenças significativas na aceitabilidade das dietas, na produção fecal diária, na porcentagem de água nas fezes e no coeficiente de indigestibilidade aparente nos minerais avaliados (P>0,05). A inclusão dos aditivos que apresentam como função principal a redução de odor fecal pode ser realizada sem interferências sobre a saúde dos animais, do ponto de vista da nutrição mineral.

The objective of this study was to evaluate the effect of including Yucca schidigera and zeolite (clinoptilolite) in commercial wet food for adult cats, the acceptability of the diets, fecal production and average daily percentage of water in the stool and the coefficient of apparent indigestible calcium, phosphorus, magnesium, sodium, potassium, iron and manganese. We used 21 adult mongrel male and female cats, 4.5 years old and with an average weight of 3.56kg, distributed in seven treatments (wet control diet, control with the addition of 125, 250 and 375ppm of Yucca schidigera and 0, 5, 0.75 and 1.0 percent of zeolite) randomly. Significant differences were not observed in the acceptability of the diets, fecal production and average daily percentage of water in the stool and the coefficient of apparent indigestible of minerals (P>0.05). Thus, we noticed that the inclusion of additives which have the main function of reducing fecal odor can be inserted into food for adult cats without negative interferences on the health of animals ready for the sight of mineral nutrition.

Influence of ZSM-5(38)/Al-MCM-41 composite molecular sieve catalysts on pyrolysis of cellulose / 生物工程学报

Pyrolysis of cellulose with different catalysts has been conducted in a fixed-bed reactor. Micro-mesoporous composite molecular sieves of ZSM-5(38)/A1-MCM-41 with different Si/A1 ratios were prepared under hydrothermal conditions. With powder X-ray diffraction (XRD), the catalyst samples were characterized. GC-MS was used to analyze the bio-oil composition. The effects of catalysts on the pyrolysis product yields were investigated and the results were compared with the results of experiments performed without catalyst under the same pyrolitic conditions. The presence of the catalysts decreased the liquid yield, while increased the moisture content. The major improvement in the quality of bio-oil with the use of catalysts was the increase of DL-2,3-Butanediol. ZSM-5(38)/A1-MCM-41(20) favored the formation of phenol and 2-methoxy-phenol. In addition, these catalysts were all benefit for the generation of small molecular compounds. Also, it was found that ZSM-5(38) was better for the production of C4-C5 compounds. And micro-mesoporous composite molecular sieves mainly promoted the production of C6-C8 compounds.

Optimization of ethylene production from ethanol dehydration using Zn-Mn-Co/HZSM-5 by response surface methodology / 生物工程学报

The effects of reaction temperature, ethanol concentration and weight hourly space velocity (WHSV) on the ethylene production from ethanol dehydration using zinc, manganese and cobalt modified HZSM-5 catalyst were investigated by response surface methodology (RSM). The results showed that the most significant effect among factors was reaction temperature and the factors had interaction. The optimum conditions were found as 34.4% ethanol concentration, 261.3 0 degrees C of reaction temperature and 1.18 h(-1) of WHSV, under these conditions the yield of ethylene achieved 98.69%.

Use of sodium chloride and zeolite during shipment of Ancistrus triradiatus under high temperature

The use of sodium chloride (0.5 g/L and 1 g/L) and zeolite (22.7 g/L) during shipment (48 h) of Ancistrus triradiatus at high temperatures (between 24.5 and 34ºC) were evaluated. Several water quality parameters (dissolved oxygen, pH, conductivity, and total ammonia) were measured before and after shipment. Glycemia was measured before shipment and at 24 and 48 h after shipment. After shipment, a resistance test was carried out in a high concentration of sodium chloride, and mortality was recorded after shipment, and 7 days post-shipment. While the two evaluated substances increased survival of A. triradiatus challenged by high temperatures during shipment, the best result was obtained with 1 g/L of sodium chloride.

O uso de cloreto de sódio (0,5 g/L e 1 g/L) e zeolita (22,7 g/L) foram avaliados durante o transporte (48 h) de Ancistrus triradiatus em altas temperaturas (entre 24,5 e 34ºC). Os seguintes parâmetros foram monitorados: pH, oxigênio dissolvido, condutividade e amônia antes e depois do transporte. Também foi mensurada a concentração de glicose no sangue antes do transporte e 0, 24 e 48 h após o transporte. Foi realizado um teste de resistência a altas concentrações de cloreto de sódio após o transporte, sendo registrada a mortalidade no final do transporte e após 7 dias. As duas substâncias testadas aumentam a sobrevivência de A. triradiatus a altas temperaturas durante o transporte, porém o melhor resultado foi obtido com o uso de 1 g/L cloreto de sódio.

Kinetics and equilibrium study of chromium adsorption on zeoliteNaX

This study aims to report Batch adsorption study of hexavalent chromium, Cr [VI] on zeoliteNaX. Kinetics of Cr [VI] adsorption and adsorption isotherms were determined by varying operating parameters such as pH, initial concentration, temperature and contact time. ZeoliteNaX was found to remove Cr [VI] in acidic solutions down to ppm level at pH of about 4. Removal rate of Cr [VI] was found to decrease as pH rises above 4.0. Langmuir, Freundlich, Temkin and Redlich-Peterson models were applied to adsorption equilibrium data to find the best amongst these models. Langmuir model with R[2] = 0.9711 best fits the adsorption data. The kinetics of adsorption was found to follow the first order reversible reaction. The separation parameter, R[L] values of less than 1.0 i.e., 0.7369, 0.5834 and 0.4828 corresponding to initial concentrations of 10, 20 and 30 mg/L, respectively indicated that adsorption of Cr [VI] on zeoliteNaX is favoured. The estimated values of thermodynamic parameters such as heat of adsorption and standard gibbs free energy confirmed the exothermic nature of adsorption of Cr [VI] on zeoliteNaX

[Determinants of natural zeolite clinoptilolite adsorption capacity for removing NO2]

NO2 is a poisonous gas that potential to cause major threat to human being health and the environment, as a result, removing this gas from environment seems to be essential. The study aimed to remove this gas from environment using Iranian natural zeolite, clinoptilolite. After crushing and preparing two sizes of 1 and 2 mm zeolite they were activated in 380 to 420 §C for 20 minutes. NO2 was produced by reaction of copper [Cu] and nitric acid [HNO3] and diluted with enough air to achieve desired concentration. A laboratory reactor set with different concentration of NO2 [20, 30, and, 45 ppm], flows through the zeolite absorbent bed was prepared. Different parameters affected No2 absorption, such as concentration, height, and diameter of zeolite bed, zeolite granulation, and activation temperature were examined. In different condition, the adsorption range of the zeolite for NO2 was varied from 0.35% W for 2mm granulation and the 20 ppm concentration to 1.5% W using 1mm granulation and 45 ppm concentration of NO2. Activation temperature of 420 §C for 20 min was the best condition removing NO2. Efficiency of 1mm granulation was higher than 2mm. Reducing parameters such as height and diameter of zeolite bed decreased but increasing concentration of gas flow increased adsorption capacity of zeolite. Using Iranian zeolite in gas masks still not recommended