Microbial 2,3-butanediol production: A state-of-the-art review

Substrate and product inhibition kinetics in succinic acid production by Actinobacillus succinogenes

Kinetics of high strength phenol degradation using Bacillus brevis.

This review focuses on the use of immobilized lipase technology for the hydrolysis of oils. The importance of lipase catalyzed fat splitting process, the various immobilization procedures, kinetics, deactivation kinetics, New immobilized lipases for chiral resolution, reactor configurations, and process considerations are all reviewed and discussed.

Hydrolysis of oils by using immobilized lipase enzyme: A review

Ecotoxicity of phenol and cresols to aquatic organisms: A review.

The Arthrobacter species can degrade phenol, o-cresol and p-cresol much faster (as reflected in high specific growth rates) than other microbes which are reported to degrade toxic compounds In mixtures, phenol and p-cresol mutually inhibited each other; the inhibition constants show that phenol degradation is strongly inhibited in the presence of p-cresol rather than reverse o-Cresol enhanced phenol degradation marginally but o-cresol degradation was not affected by the presence of phenol

Biodegradation of phenol and cresol isomer mixtures by Arthrobacter

The biochemical route is identified to be one of the simplest and cheapest means by which valuable chemicals are being synthesized. Microorganisms play a vital role in carrying out these processes. However, the kinetic studies relevant to this process is scarce. Most often inhibition effects due to either cells or substrates or products affect the performance of such processes. This paper deals with the study of various model equations for substrate inhibition kinetics. An attempt has been made to study the applicability of various model equations for substrate inhibited systems by fitting their experimental data and evaluating various parameters including the standard deviations in each case. Finally, a new model has been brought out which gives the best fit for almost all the systems.

Extended monod kinetics for substrate inhibited systems

The effect of a nontoxic easily degradable substrate, glucose, on the biodegradation of toxic pollutant, phenol, was studied in batch reactors using a phenol degrading culture (Arthrobacter species). The effect of glucose on phenol degradation was determined at different glucose concentrations. The effect of different inoculum on substrate removal in a phenol and glucose mixture was also studied. Results indicated that when a mixed substrate (phenol and glucose) was used, phenol acclimated population showed an initial preference for phenol and utilised glucose after phenol removal. However phenol degradation rate was reduced in the presence of glucose. It was also observed that phenol degradation was completely inhibited when the glucose concentration exceeds 2 g/l. The substrate removal pattern changed completely when inoculum was drawn from mixed substrate acclimatised culture. The glucose utilisation started immediately and the rate of glucose utilisation was not affected by the presence of phenol. The phenol degradation also started simultaneously. In presence of phenol only, the rate of phenol degradation for the culture acclimatised to mixed substrates was lower than that of phenol acclimatised culture. These results indicate that nontoxic substrate can affect the biodegradation of toxic pollutants is suitable and acclimatisation may be necessary for biodegradation of mixed substrate.

Studies on biodegradation of a mixture of toxic and nontoxic pollutant using Arthrobacter species

The toxic effects of phenol, a common constituent of many industrial effluents, necessitates treatment of the polluted streams. Biodegradation is a popular technique and enjoys many advantages. The degradation of phenol with Arthrobacter species is studied in batch cultures and it is observed that the substrate is inhibiting. The fit of various models, including the model proposed earlier by us [17], to the experimental data is studied. The model is used to fit available data in literature, which unfortunately is very sparse. In all the cases the present model fits the data best.

Biodegradation of phenol by arthrobacter and modelling of the kinetics

The immobilization of lipase from Candida lipolytica on alumina by adsorption for the hydrolysis of ricebran oil is described. Some of the factors which influence the activity of immobilizate and the stability of immobilizate are discussed. About 69% of the initially added enzyme activity is found in the biocatalyst when immobilized at pH 7.2. The stability of the immobilized enzyme to different pH and temperature conditions has also been studied.

A. Baradarajan

Papers

Biodegradation of phenol and cresol isomer mixtures by Arthrobacter

Extended monod kinetics for substrate inhibited systems

Studies on biodegradation of a mixture of toxic and nontoxic pollutant using Arthrobacter species

Biodegradation of phenol by arthrobacter and modelling of the kinetics

Studies on immobilization of lipase on alumina for hydrolysis of ricebran oil