Effect of Culture Conditions on the Production of Penicillin G Acylase from Arthrobacter Viscosus (ATCC 15294)

Ambrish Rathore, Archana Pundle and Asmita Prabhune

This article reports studies concerning the extracellular production of Penicillin G acylase (PGA) by the Gram-positive bacteria Arthrobacter viscosus. PGA is industrially important enzyme in the production of 6-aminopenicillanic acid (6-APA), which is an essential intermediate for the production of various semisynthetic b-lactam antibiotics. Enzyme production involves several steps resulting in many operational variables to be studied. PGA of Arthrobacter viscosus is secreted in the fermentation broth. Enzyme production in this strain is induced by phenylacetic acid (PAA). Various concentrations of phenylacetic acid (PAA) were tested for the highest induction and an induction level up to 2 fold was observed. Fermentation parameters like inducer concentration, initial pH of fermentation medium, aeration levels and growth profiles were performed in batch fermentation under shake flask conditions. Various carbon and nitrogen sources were evaluated for their effect on extracellular PGA production at 30 °C. Maximum specific PGA production was observed when the fermentation was carried out for 48 hours at pH 7.0 with 0.2% (w/v) PAA in 75 ml of medium in 500 ml Erlenmeyer flask.

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Bioextraction of Grapefruit Pectin by Kluyveromyces Marxianus

Saleh A. Kabli and Saleh M. Al-Garni

Microbial and chemical extraction of pectin from some agro-industrial wastes (grapefruit, orange fruit, mango fruit, lemon fruit and onion scales) proved that grapefruit waste (GFW) contains more amounts of pectin than the other wastes. GFW contains about 37.5% pectin, 17.2% soluble sugars, and 14.3% holocellulose of its dry weight. The highest bioextraction of GFW pectin by Kluyveromyces marxianus (35.6%), extracellular protein(5.5%) and protopectinase activity(12.02µ/ml), as well as, yeast gowth (342x108cfu/ml) were obtained under the following optimized fermentation conditions: absence of yeast extract, 0.4% peptone, 1.0% glucose and 8 % grapefruit waste (added at zero time of incubation), under shaked conditions (200 shakes/min) for 18h at 30°C, pH 5 and seed culture of 24h (old) at 4 % level.

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Typhoid Fever in Nigeria: Analysis of Phenotypic and Genotypic Methods of Salmonella Typhi Identification

Smith Stella Ifeanyi, Odunukwe Nkiru N, Niemogha Mary-Theresa, Omonigbehin Emmanuel Adedayo, Bamidele Moses, Akinsinde Kehinde Adewale, Goodluck Helen, Fesobi Toun, Brai Bartholomew and Bakare Bode

To compare phenotypic and genotypic methods of Salmonella typhi identification in Nigeria. Febrile and non-febrile patients were screened for S. typhi, malaria parasite, widal test and antibiotic patterns while biotyping, PCR-RAPD and plasmid profiles were used for typing. Twenty-six percent were positive for Salmonella typhi amongst the febrile patients. More females (71%) than males had typhoid fever from S. typhi. Majority of the isolates were from stool samples (57%), while the blood isolates were 43%. Nine of the isolates were positive for malaria parasite.When the isolates were grouped according to biotypes, 86% were biotype I, while 14% were biotype II. The isolates were grouped into nine according to their antibiotic susceptibility patterns. The antibiotic susceptibility patterns showed the pattern of resistance to be AprTetrCotrChlrTmr (29%). When the isolates were typed using plasmid profiles and RAPD patterns, they gave about 5 groups each. Interestingly, the isolate from the negative control stood out on a different group from the others, from the plasmid profile. Antibiotic patterns, plasmid profiles and PCR-RAPD are useful in the typing of our local isolates.

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Dextran Synthesis by Dextransucrase Leuconostoc Mesenteroides FT 045 B

J. Contiero, M. Cortezi, J. C Marconato, S. M. M. Franchetti and R. Monti

The production of dextransucrase enzyme by a strain of Leuconostoc mesenteroides (FT 045 B) isolated from a Brazilian sugar-mill and alcohol plant, was investigated with a view to optimizing process. The best temperature for enzyme production in batch fermentation was 25°C, at which the enzyme activity was 3.2 DSU/mL. With molasses as a carbon source at a concentration of 97.3 g/L L. mesenteroides FT045B produced 11.6 DSU/mL in batch fermentation. When sucrose was used as a carbon source, concentrations of 3 and 4% showed respectively 10.8 and 10.7 DSU/mL of dextransucrase activity. In vitro dextran production by crude cell-free enzyme (11.5 DSU/mL) in 600g/L sucrose showed an increase in viscosity after 24 hours of reaction. The FTIR spectrum of the polymer synthesized showed all the main bands assigned to groups formed in standard commercial dextrans (515.000Da and 9.300Da) from Sigma Co.

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Identification of Nucellar seedlings of Poncirus Trifoliata through the Combination of Morphological and RAPD marker

K.J. Wable, H.B. Patil , S.G. Rajput and V.U. Patil

As citrus (Poncirus trifoliate) cultivars exhibit apomixes and poly embryony, which are undesirable in citrus breeding programme since correct identification of hybrids is hindered. These apomictic embryos, which are called nucellar, are to be identified and removed. So, present study was conducted to standardize the methods of identification of the nucellar embryony in crosses involving poly embryonic cultivars through the combination of morphological and molecular markers, mainly using RAPD at early stage of development.

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Effects of Administration of Ethanolic Extract of Vernonia Amygdalina Del on Kidney Function of Experimental Rabbit Model

I. Ijeh and A.T. Adedokun

Administration of ethanolic extract of Vernonia amygdalina del to male experimental rabbits resulted in significant (p<0.05) increases in relative kidney weight at 100mg/kg body weight and 500mg/kg body weights. Relative kidney weight increased from 8.9 x 10-3± 1.0 x 10-4 to 9.3 x 10-3± 5.5 x 10–4 in the low dose group and 1.0 x 10-2 ± 9.5 x 10-4 in the high dose group. Also there was a significant (P<0.05) loss in body weight in groups administered with the extract, while control group gained 29.90g, the low dose group lost 3.80g and high dose group lost 1.20g. Serum urea nitrogen decreased from 203.4± 13.4 mg/100ml in the control group to 167.8 ± 16.7mg/100ml in the low dose group and 156.7mg/100ml in the high dose group. Serum creatinine increased in the low-dose group and decreased in the high dose group. Our finding indicates that the administration of the extract could have some effect on the kidney clearance functions.

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Biosorption of Azo Dye (AR 66) by Hypnea valentiae and Ulva fasciate

M. Sukumar, A. Sivasamy and G. Swaminathan

The biosorption and the biological decolorization of chromophores of simulated dye bath and original dye house effluents using the marine algae Hypnea valentiae and Ulva fasciate were reported in detail. The effect of independent variables such as pH, temperature, concentration and agitation for each dye molecules and dye house effluent on biosorption was studied. It was observed that the optimum pH for biosorption was found to be 4.5 for Hypnea valentiae and Ulva fasciate. The kinetics of biosorption was also carried out. It was observed that the percentage of adsorption was found to be above 80% for both the algae biomass.

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Integrated Management of Phomopsis Canker of Tea with Fungicides and Biocontrol Agents

P. Ponmurugan and U.I. Baby

An experiment was conducted to study the efficacy of certain fungicides and biocontrol agents in controlling Phomopsis canker disease of tea under greenhouse and field conditions. Soil application and wound dressing of biocontrol agents was found to be superior to fungicides in controlling phomopsis canker under both greenhouse and field conditions. Mere wound dressing of carbendazim was found ineffective while the same as soil drenching was effective under greenhouse condition. Various treatments healed the wound to varying degree and improved the biometric physiological, and biochemical parameters to a greater extend. Among the biocontrol agents tested, Gliocladium virens was better than Trichoderma harzianum in terms of curing cankers and increasing yield potential.

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Selection of Yeast Isolates for Rice Wine Fermentation Based on their Oenological Characters

M. Sundar, S. Gunasekaran, M. Sukumar, M. Sivarajan and R. Rajesh Kumar

Wine is a natural, non-toxic, healthful fermented alcoholic beverage, rich in calories, vitamins and minerals. Saccharomyces cerevisiae had served as one of the best model systems for the production of beer, bread and wine. Different yeast isolates were isolated from rotten fruits of Grapes, Papaya, Banana, Sapota, Mango, Orange, Jack and Molasses collected from different places of Coimbatore and named based on their source namely YG, YP, YB, YS, YM, YO YJ and YMs. The yeast isolates were tested for performance in rice wine production compared with standard yeast strain (YI) obtained from Imtech. The different yeast isolates were tested for their oenological characters by inoculating 3 ml @ 2 x 106 cells /ml in the rice mash. The time taken for initiation of fermentation by the yeast isolates varied between 3.00 to 5.30 h and the isolate YMs was able to initiate fermentation within 3.00 h. The isolate YMs recorded higher fermentation rate of 0.26 g CO2 day–1. The production of H2S was estimated by blackening of the filter paper and was higher in the isolates of YS, YO and YJ. The highest fermentation vigour of 12.8% was noticed in YMs yeast isolate which was at par with the standard YI and YG isolates, but failed to show significance among the different yeast isolates. In foaming, all the isolates represented positive characters except YMs. All the yeast isolates had produced desirable bouquet.

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Production of Protein and Amylase Activity by Fungal Cultures in Solid State Fermentation

C. Pothiraj and N. Raman

The solid waste of agro industry using cassava was fermented by Aspergillus niger, Aspergillus terreus and Rhizopus stolonifer in solid state fermentation. Cassava waste contained dry wt. of 52 % starch and 2.9 % protein. The highest amylase activity was observed on the eigth day in R.stolonifer mediated fermentation. It was found that R.stolonifer was more efficient in bio-converting cassava waste into fungal protein (90.24 mg/g) than Aspergillus niger and Aspergillus terreus.

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Herbicide-resistant Cyanobacterial Mutant Causing Exogenous ATP Requirement for Nitrogen Fixation

D.K. Shrivastava, F.K. Pandey, A.K. Shrivastava and A. Vaishampayan

The nitrogen-fixing cyanobacteria Nostoc muscorum has been found sensitive to the herbicide Sandoz 6706 [4-chloro-5 (dimethy amino) –2- (a, a, a-trifluoro-m-tolyl-3 (2H) pyridazinon] at a dose of 10 to 20 mg/ml applied for 15 min. The toxicity was found to be more severe in N2 medium than in combined N2 medium and the same was reversible on an exogenous supplementation with 3mM glucose or 5 mm ATP, serving as or energy source, respectively in this organism .A mutant of this Cyanobacterium resistant to 1000 mg/ml Sandoz 6706 (Sanr) has been isolated and characterized to be incapable of N2-mediated growth and nitrogenase activity unless supplied with exogenous ATP supply. This strain has shown a simultaneous cross-resistance to methylalanine, a well known inhibitor of photophosphorylation, in medium unsupplemented with ATP. This behaviour of the Sanr mutant suggests the existence of a defective cyclic photophosphorylation in its photosynthetic system.

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Nanotechnology: A Future Approach in Cancer Treatment

M.N. Venkatesh S.S. Satish and B.V. Srinivas

Cancer is a leading cause of death worldwide. Unfortunately even after decades of research, there has been no substantial improvement in diagnosis and treatment of cancer. Nanotechnology, which has developed recently, holds promise in this regard. It shows great promise for providing us in the near future with many breakthroughs that will change the direction of our approach in combating cancer. However, as true to any technology, nanotechnology needs to answer certain legal and ethical issues. But with our increase understanding in nanotechnology, the issues may be overcome and in near future it may be successfully employed in the field of medicine.

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