Mukhtar A. Khan

Dietary methionine requirement of fingerling Indian major carp,Cirrhinus mrigala(Hamilton)

Indian major carp, Cirrhinus mrigala fingerling (3.85 ± 0.50 cm, 0.50 ± 0.02 g) were fed isonitrogenous and isocaloric diets (40% CP, 4.28 kcal g−1, GE) containing casein, gelatin and crystalline amino acids with graded levels of L- methionine (0.50, 0.75, 1.00, 1.25, 1.50 and 2.00 g/ 100 g, dry diet) with 1.00% cystine fixed, to determine its dietary methionine requirement. A feeding trial was conducted in triplicate for six weeks. Diets were fed twice a day at 0800 and 1600 h at 5% of body weight/day. The ration size and feeding regime were worked out prior to the start of the feeding trial. Weight gain (158%) and food conversion ratio (1.45) were significantly (P < 0.05) higher in fish fed diet containing 1.00% methionine with 1.00% cystine fixed. Second degree polynomial regression analysis of the weight gain data indicated the dietary methionine requirement to be 1.20 g/100 g of dry diet, corresponding to 3.00% of dietary protein. Second degree polynomial regression analysis was also employed to determine the relationship between food conversion ratio (FCR) and dietary methionine levels which indicated that the best FCR occurred at approximately 1.20% dietary methionine level. Carcass composition of fish fed diet containing graded levels of methionine varied significantly (P < 0.05) except carcass ash content which showed insignificant (P > 0.05) differences among the dietary methionine levels.

Dietary branched-chain amino acid valine, isoleucine and leucine requirements of fingerling Indian major carp, Cirrhinus mrigala (Hamilton)

Three 8-week growth experiments were conducted to quantify the requirements of the fingerling Cirrhinus mrigala for the dietary branched-chain amino acids valine (experiment 1), isoleucine (experiment 2) and leucine (experiment 3). Six isonitrogenous (400 g/kg) and isoenergetic (17.90 kJ/g) test diets were formulated with a gradation of 2.5 g/kg for each test amino acid, valine (7.5-20 g/kg), isoleucine (5.0-17.5 g/kg) and leucine (7.5-20 g/kg), and fed to randomly stocked fish in circular troughs. In experiment 1, the maximum weight gain (312 %), best feed conversion ratio (FCR; 1.45) and best protein efficiency ratio (PER; 1.72) were obtained in fish fed 15.0 g dietary valine/kg. In experiment 2, the highest weight gain (317 %), best FCR (1.47) and best PER (1.70) were recorded at 12.5 g dietary isoleucine/kg, and in experiment 3, the highest weight gain (308 %), best FCR (1.46) and best PER (1.71) were noted at 15.0 g dietary leucine/kg. A quadratic regression analysis of weight gain, FCR and PER data showed an optimum requirement at 15.9, 15.0 and 14.8 g/kg for valine, 13.2, 12.3 and 12.1 g/kg for isoleucine and 15.6, 15.4 and 15.1 g/kg for leucine in dry diets. Low body moisture and higher protein were noted in fish fed diets containing 15.5, 12.5 and 15.0 g valine, isoleucine and leucine per kg, respectively. Body fat increased with increasing levels of the branched-chain amino acids. On the basis of a regression analysis of growth data, it is recommended that a diet for C. mrigala should contain valine at 15.2, isoleucine at 12.6 and leucine at 15.4 g/kg dry diet, corresponding to 38.0, 31.5 and 38.5 g/kg dietary protein, respectively.

Nanostructured porous silicon as functionalized material for biosensor application

In this work by means of PL, FTIR and XPS techniques, state-of-the-art porous silicon (PS) films with good mechanical and optical properties have been effectively utilized for the biofunctionalization purpose for its possible application in immunosensors. The functionalization of the PS surface has been achieved by silanization process using aminopropyltriethoxysilane (APTS) as a precursor. The presence of reactive amino groups on the PS surface along with glutaraldehyde as a linker aids in the covalent binding of the antibody (Human IgG) onto the PS surface. Different antigen concentrations can be detected with a good reproducibility with this technique which opens a huge possibility of using this biofunctionalized material for future biosensors.

Dietary Valine Requirement of Fingerling Catla catla

A 12-week feeding trial was conducted to determine the dietary valine requirement of fingerling Catla catla (3.50 ± 0.15 cm, 0.63 ± 0.04 g). Seven casein gelatin-based diets (33% crude protein; 3.34 kcal/g digestible energy) containing graded levels of valine (0.51%, 0.69%, 0.91%, 1.12%, 1.31%, 1.49%, 1.71% dry diet) were fed to triplicate groups of fish to apparent satiation at 08:00, 12:30, and 17:30 h. Absolute weight gain (AWG), feed conversion ratio (FCR), specific growth rate (SGR%), protein efficiency ratio (PER), protein productive value (PPV), valine retention efficiency (VRE), valine gain (VG), energy retention efficiency (ERE), and carcass protein improved significantly (P < 0.05) with the increasing concentrations of dietary valine from 0.51% to 1.12%. Quadratic regression analysis of AWG, PPV, DPD, VG, ERE, and carcass protein at 95% maximum (Y95%max) response against varying levels of dietary valine yielded the requirement at 1.04%, 1.03%, 1.05%, 1.04%, 1.01%, and 0.98% of dry diet, respectively. It is recommended that inclusion of valine at 1.02% of dry diet, corresponding to 3.09% of dietary protein, is optimum in formulating valine-balanced feeds for fingerling C. catla.

Effect of dielectric constant on Rf values of metal ions in some formic acid-alcohol solvent systems

Correlations between dielectric constant and R(f) values for numerous alcohol-formic acid systems have been made. Most metal ions behave similarly, but arsenic(III), antimony(III) and tin(II) show different properties.

Growth, Feed Conversion, and Nutrient Retention Efficiency of African Catfish, Clarias gariepinus, (Burchell) Fingerling Fed Diets with Varying Levels of Protein

Growth, feed conversion, and nutrient retention efficiencies of African catfish fingerling, Clarias gariepinus (5.22 ± .07 cm; 8.22 ± 0.03 g), fed diets with varying levels of protein were assessed by feeding seven casein/gelatin based isocaloric (17.62 kJ/g GE) experimental diets with graded levels of dietary protein (20%, 25%, 30%, 35%, 40%, 45%, and 50% of the diet) to triplicate groups of fish to apparent satiation for eight weeks. Effects of feeding these diets on live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER), protein retention efficiency (PRE%), and energy retention efficiency (ERE%) were assessed. Maximum LWG% (867%), PER (2.01), highest PRE (32%), ERE (69%), best FCR (1.39), and maximum body protein were recorded in fish fed diet containing 35% protein. On the basis of the second-degree polynomial regression analysis of the above response variables, it is recommended that the inclusion of protein in the range of 34.4%–39.6% is optimum for maximizing growth potential, feed conversion, and nutrient retention in African catfish fingerling, Clarias gariepinus.

Precipitation chromatography on strontium chromate paper

SummaryPrecipitation chromatography of various cations on strontium chromate impregnated paper is performed. Some good separations are reported with strontium nitrate and ammonium hydroxide developers. Silver, mercury and lead ions can also be determined quantitatively.ZusammenfassungVerschiedene Kationen werden auf mit Strontiumchromat imprägniertem Papier getrennt. Zur Entwicklung dienen Strontiumnitrat- oder Ammoniaklösung. Silber, Quecksilber und Blei können auch quantitativ bestimmt werden.

Dietary pyridoxine requirement of fingerling Channa punctatus (Bloch) based on growth performance, liver pyridoxine concentration, and carcass composition

ABSTRACT Seven casein gelatin-based diets containing 450 g/kg CP and 18.39 kJ/g GE with different levels of pyridoxine (0, 2, 4, 6, 8, 10, and 12 mg/kg diet) were fed to fingerling Channa punctatus (4.66 ± 0.46 g) for 12 weeks to determine pyridoxine requirement. Highest absolute weight gain (AWG; 25.81 g/fish, P < 0.05), protein retention (PRE; 23.69%, P < 0.05), energy retention efficiencies (ERE; 69.63%, P < 0.05), and minimum feed conversion ratio (FCR; 1.48) were noted at 8 mg pyridoxine/kg diet. However, liver pyridoxine content achieved the positive correlation as the dietary pyridoxine increased up to 10mg/kg. On the basis of broken-line analysis of AWG, PRE, FCR, and liver pyridoxine data, pyridoxine requirement is recommended between 7.6 and 10.4 mg/kg of dry diet.

Hydrosilylation of 1‐dodecene on Nanostructured Porous Silicon Surface: Role of Current Density and Stabilizing Agent

We report the formation of nanostructured PS on boron doped p‐type silicon wafer (100) by electrochemical anodization using aqueous hydrofluoric acid and isopropyl alcohol solution at different current densities 20 mAcm−2 and 50 mAcm−2 with pore size being 20–30 nm and 50–60 nm, respectively. For organic functionalization of PS surface 1‐Dodecene treatment under UV light was done. PL, FTIR and XPS studies have been carried out to characterize the PS after surface modification using dodecene. Stability studies were performed under normal ambience and humid condition for as‐anodized (Fresh PS) and dodecene‐treated samples. It is observed that the dodecene functionalized samples were more stable than as‐anodized porous silicon. The present study demonstrates that nanoporous silicon can provide chemically modified stable and high surface area for the sensing applications of PS.

Attachment Of Streptavidin‐Biotin On 3‐Aminopropyltriethoxysilane (APTES) Modified Porous Silicon Surfaces

Nanostructured porous silicon (PS) has a large surface area that can be well controlled and modified to have a high specificity for biomolecules. These properties make it a very promising biomaterial, in particular for sensing devices that need to be linked to the biological system and completely compatible with standard integrated circuit processes. We report the formation of nanostructured PS on boron doped, p‐type silicon (100) wafers by electrochemical anodization, using aqueous hydrofluoric acid and isopropyl alcohol solutions and a constant current density 50 mA/cm2. The pore diameter can be tuned by varying the etching conditions. The interaction of streptavidin with biotin was studied on 3‐aminopropyltriethoxysilane (APTES) functionalized PS surfaces using infrared absorption spectroscopy to characterize the surface at each step, including subsequent reaction steps. These studies show that the streptavidin‐biotin interaction on modified PS surfaces depends on the details of the APTES adsorption process.Nanostructured porous silicon (PS) has a large surface area that can be well controlled and modified to have a high specificity for biomolecules. These properties make it a very promising biomaterial, in particular for sensing devices that need to be linked to the biological system and completely compatible with standard integrated circuit processes. We report the formation of nanostructured PS on boron doped, p‐type silicon (100) wafers by electrochemical anodization, using aqueous hydrofluoric acid and isopropyl alcohol solutions and a constant current density 50 mA/cm2. The pore diameter can be tuned by varying the etching conditions. The interaction of streptavidin with biotin was studied on 3‐aminopropyltriethoxysilane (APTES) functionalized PS surfaces using infrared absorption spectroscopy to characterize the surface at each step, including subsequent reaction steps. These studies show that the streptavidin‐biotin interaction on modified PS surfaces depends on the details of the APTES adsorption pr...