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1.
Branch internodes of mature plants and stem internodes of seedlings of Fortunella hindsii flowered in vitro on half-strength MT (Murashige and Tucker 1969) basal medium supplemented with benzyladenine, adenine, 6---dimethylallylaminopurine and kinetin. The highest percentage of flowering was achieved with explants originating from branch internodes of flowering plants close to the apex on half-strength MT basal medium containing 5% sucrose and 0.01 mg 1–1 BA in light. Exposure to darkness for more than 3 weeks followed by re-exposure to light reduced flowering. Flowering required a 4-day exposure to BA, but shoot formation could be initiated even without exposure to BA. First branch internode segments on MT basal medium containing 5% sucrose were prolific in flower (85%) production. The sucrose treatment affected the flower bud size distribution. There were about 13 flower buds per culture in the largest size category (>5 mm).  相似文献   
2.
Mycopathologia - Candida albicans has been reported globally as the most widespread pathogenic species contributing candidiasis from superficial to systemic infections in immunocompromised...  相似文献   
3.
Biomechanics and Modeling in Mechanobiology - This study employs a computational approach to analyse the impact of morphological changes on the structural properties of biodegradable porous Mg...  相似文献   
4.
The Genotoxic Effect of the New Acaricide Etoxazole   总被引:2,自引:1,他引:1  
Etoxazole is a member of the diphenyl oxazoline class of insecticide, which was newly developed for use on pome fruits, cotton and strawberries as an acaricide. In the present study, genotoxic effects of acaricide etoxazole (ETX) (miticide/ovicide) were investigated using chromosome aberration (CA) test, sister chromatid exchange (SCE) test, and micronucleus test in human lymphocytes. ETX induced the CAs at all concentrations (5, 10, and 20 g/ml) for 24 h and also induced the CA at the highest concentration (20 g/ml) for 48 h only. The inducing the CAs for 48 h treatment period was dose-dependent. In addition, it induced the SCE at all concentrations and treatment periods in a dose-dependent manner as well. Although ETX decreased the mitotic index (MI) at all concentrations and treatment periods dose-dependently, it did not decrease the replication index (RI) when compared to the negative and solvent controls. In addition, ETX induced the micronucleus at all concentrations except 5 g/ml for 48 h. This inducing was dose-dependent as well. It can be concluded that ETX has a potential genotoxic effects in cultured human peripheral lymphocytes.  相似文献   
5.
Dimethyl adipate (DMA) was synthesized by immobilized Candida antarctica lipase B-catalyzed esterification of adipic acid and methanol. To optimize the reaction conditions of ester production, response surface methodology was applied, and the effects of four factors namely, time, temperature, enzyme concentration, and molar ratio of substrates on product synthesis were determined. A statistical model predicted that the maximum conversion yield would be 97.6%, at the optimal conditions of 58.5°C, 54.0 mg enzyme, 358.0 min, and 12:1 molar ratio of methanol to adipic acid. The R2 (0.9769) shows a high correlation between predicted and experimental values. The kinetics of the reaction was also investigated in this study. The reaction was found to obey the ping-pong bi-bi mechanism with methanol inhibition. The kinetic parameters were determined and used to simulate the experimental results. A good quality of fit was observed between the simulated and experimental initial rates.  相似文献   
6.

Background  

Cosmeceuticals are cosmetic-pharmaceutical hybrids intended to enhance health and beauty of the skin. Nanocosmeceuticals use nano-sized system for the delivery of active ingredients to the targeted cells for better penetration. In this work, nanoemulsion from palm oil esters was developed as a delivery system to produce nanocosmeceuticals. The stability of the resulting formulation was tested using various methods. In addition, the effect of components i.e. Vitamin E and Pluronic F-68 on the formulation was also studied.  相似文献   
7.
Five out of the nine benzene–toulene–ethylbenzene-xylene (BTEX) tolerant bacteria that demonstrated high protease activity on skim milk agar were isolated. Among them, isolate 115b identified as Bacillus pumilus exhibited the highest protease production. The protease produced was stable in 25% (v/v) benzene and toluene and it was activated 1.7 and 2.5- fold by n-dodecane and n-tetradecane, respectively. The gene encoding the organic solvent tolerant protease was cloned and its nucleotide sequence determined. Sequence analysis revealed an open reading frame (ORF) of 1,149 bp that encoded a polypeptide of 383 amino acid residues. The polypeptide composed of 29 residues of signal peptide, a propeptide of 79 residues and a mature protein of 275 amino acids with a calculated molecular mass of 27,846 Da. This is the only report available to date on organic solvent tolerant protease from B. pumilus.  相似文献   
8.
9.

Background  

Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0) as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%). Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification.  相似文献   
10.
Engkabang fat esters were produced via alcoholysis reaction between Engkabang fat and oleyl alcohol, catalyzed by Lipozyme RM IM. The reaction was carried out in a 500 ml Stirred tank reactor using heptane and hexane as solvents. Response surface methodology (RSM) based on a four-factor-five-level Central composite design (CCD) was applied to evaluate the effects of synthesis parameters, namely temperature, substrate molar ratio (oleyl alcohol: Engkabang fat), enzyme amount and impeller speed. The optimum yields of 96.2% and 91.4% were obtained for heptane and hexane at the optimum temperature of 53.9 °C, impeller speeds of 309.5 and 309.0 rpm, enzyme amounts of 4.82 and 5.65 g and substrate molar ratios of 2.94 and 3.39:1, respectively. The actual yields obtained compared well with the predicted values of 100.0% and 91.5%, respectively. Meanwhile, the properties of the esters show that they are suitable to be used as ingredient for cosmetic applications.  相似文献   
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