Attended the Conference - 31ST Symposiums on Biotechnology for Fuels and Chemicals
Report for the month of May:
Attended the conference - 31ST Symposiums on Biotechnology for Fuels and Chemicals.
Third set of samples were collected on 30th April and the same way as before the microbial characterization was done using PDA and LBA. Though there was not much difference when compared to the second control and third batch, there was increase in the activity of the discoloration of the dyes when isolated cultures were inoculated.
Later the Biomass samples were collected from all the three sets and were grinded for the analysis of FTIR, GC-MS and NMR.
Session I have attended:
- Sunday ,May 3rd ,2009 - Microbial Sciences.(Session 2 )
- Monday ,May 4th ,2009 – Biomass pretreatment (Session 3)
- Monday ,May 4th ,2009 - Enzyme Sciences ( Session 5) /Partial &
Microbial sciences (Session 6)/ Partial
Session 2- Microbial Sciences
In the microbial science (session 2) there was presentation on work done in the areas of saccharomyces cervisea strain development for fermentation of pentose sugars.
The strains such as Zygomonas mobilis,Saccharomyces cervisea were constructed through metabolic engineering and cloning respectively.Zygomonas mobilis was engineered in a way where in the xylitol and xylitol phosphate pathway were determined and gene responsible for these were inactivated which resulted in higher ethanol yield as xylitol production decreased the ethanol yield.
There was a presentation on constructed yeast strain capable of carbon dioxide capture during ethanol fermentation .They isolated the genes responsible for producing photosynthetic enzymes from cynobacteria and heterogeneously expressing it in yeast .They used yeast actin, pgk1 promoters.But, the work was still ongoing and the strain was still under construction. In one of the other presentations yeast was used to metabolic engineering in such a way that it has cellulosic fermentation .
On of the presentation, Yeast strain was constructed in a way that apart from fermentation of cellulosic ethanol it produces lactic acid at a low Ph .This was done by metabolic engineering in a way to replace yeast ethanol pathway by lactic acid pathway.
Session 3 – Biomass pretreatment
In this session, a different method of pretreatment was presented where in switch grass was pretreated by using sub critical water at a temperature of 80 degrees centigrade and 136 bar pressure. This process mainly showed structural changes in hemicellulose.When the temperature is further increased the biomass converts to biocrude where in it becomes a mixture of oxygenated hydrocarbons. and liquefaction of this mixture was showed to take less than 20 minutes which was surprising .
There was another presentation of comparison of different thermo chemical conversion methods used for pretreatment on switch grass such as ammonia fiber expansion, ammonia recycle percolation, dilute sulphuric acid, hot water, lime, in combination with enzymatic hydrolysis.
Ionic liquids were used to dissolve lignin based on the addition of anti solvent agent at atmospheric pressure from Biomass. This method showed a pretreated biomass which is more readily hydrolysable than others, though the commercial use of this method still stands as challenge.
There was another presentation on the structural changes which occur during AFEX process in the lignocelluloses cell wall. Where in the deposition of AFEX extractives in the cell wall were clearly presented using SEM, TEM, studies. Several degradation products like phonolic and other organic acids were also qualified using GC-MS, LC-MS/MS.
Session 6- Microbial science
A presentation was given on the construction of novel enzymes and deconstruction enzymes by using metagenomics,here they used 16 S RNA Sequencing methods where in they found five candidate based on the homology to enzyme families which are mostly cellulose,hemicellulase and xylanase activities. They also constructed a lambda based expression library of the isolated strain.
Other presentation in this session was on isolating cellulolytic extreme thermopiles from hot springs of California. The temperatures were maintained at 90 degrees centigrade and were identified by 16 s RNA. After the confirmation by different methods tey tried to optimize the media for higher yield of cellulose degradation
In an other presentation, pencillium decumbens was used for better cellulose production by genome shuffling of a industrial catabolite repression resistant strain .with its mutant higher yield of glucose from corncob was shown when fermented broth of fusants as crude cellulase was used. This was shown due to the increased secretion of extra cellular proteins.
Session 10: Enzyme science and technology
In this session, the 5th presentation was on engineered cellulases on their natural substances. They choose Beta-glucosidase mutants on cellulobiose which they identified based on random mutant library of the paeni bacillus polymyxa beta – glucosidase .there was a 11 fold increase in the thermo stability at 50 degrees centigrade.
There was another presentation given on a 3-D structure of an intact hypcrea-jecoria glucoamylase. They showed catalytic domain and the starch binding domain .they gave us a clear idea of how the substrate is directed towards the active site.
Nanoscale phenomena were used to identify the enzyme process on the macro scale conversion of cellulose. The AFM technique, where in they showed images of enzymes attached to the substrate and the cellulosic microfibrills .Here, enzyme loading of 15 FPU /g substrate of od solid was used at 50 degree centigrade.
Ionic liquid pretreatment monitoring and analyzing f process streams was shown for pretreatment of lignocelluloses Biomass .they showed the measurements of optimized ionic liquid pretreatment conditions for selective depolymerisation of lignin.
I have found this conference very useful. I had a very knowledge gaining experience. I have got a few ideas after I attended the conference which I would like to apply to my present ongoing project, they are:
1) In my project of the study of lignocellulosic degradation in soil ,I wasn’t to apply AFM technique for identifying the macro changes which are occurring in the lignocellulosic microfibrills in the Biomass.
2) Use of 16 s RNA methods for conducting metagenomics in soil ,there by helpful in isolating strains which are capable of degrading lignin.