Questions related to Bioprocess Technology
if can use spray drying, do we need to concentrate enzyme after chromatography process before entering the spray dryer?
most of the research gives information on lab-scale operation conditions like temperature and volume. so may know any resources to scale up these parameters into larger-scale/ industrial scale?
thank you for your response.
Normally bacterial cellulose produced from fermentation was in the form of gelatinous layer. Almost 98% of their structure was water. If this gelatinous layer is dry in oven it will become a very thin layer film thus hard to be grind.
My current research is in the carbon flux distribution of L. rhamnosus in a biofilm reactor and I am struggling to find research pertaining to the continuous metabolic analysis in literature. Any help would be highly appreciated.
I know one kit but I am looking preferentially for some colorimetric analysis or quantification using fluorescence spectroscopy. Help regarding any of the methods would be appreciated.
I have a P. pastoris MutS phenotype which express very well in shaking flasks. I was trying to scale up the culture in a fermentor.
The culture was behaving normally for most of the fermentation process, but as soon as I started the methanol feeding (after a DO spike to make sure all the glycerol was consumed) the pH started to rise and the acid pump worked for the whole methanol feeding process.
I took samples at different time intervals and check them for protein expression. What I noticed is that the protein started to express as soon as 3 hours after the induction, then the expression increased in the next hours to a peak expression at 9 hours of induction. After that the cells were expressing less and less until the end of the fermentation.
Comparing the expression level of the peak in the fermentor (9 hours) and the expression in flasks for 48h, in the fermentor I anyway got 5x less protein than flasks.
Do you have any idea how to improve the expression?
Why the pH of the culture was increasing during methanol feeding?
Decrease in protein expression, could possibly due to no more nitrogen source in the medium?
The medium I used was the "Basal salt medium" as described by the invitrogen guidelines and the only nitrogen source was the ammonium hydroxide also used to keep the pH at 5.0
Thank you very much for your help,
I'm a new researcher who research in Microbial Fuel Cell by adopting yeast (S. cerevisiae) as a biocatalyst. But one of the issue is the reaction mechanism: glucose + H2O --> CO2 + 24H+ + 24 e- is obtained from anaerobic condition or aerobic condition? some references said from anaerobic condition, but also some references said from aerobic condition. It makes me a little bit confused.
Pichia pastoris is fermented for recombination protein.
I set fermentation condition that DO value 50%.
I want reducing the pure oxygen rate, but maintain or increase DO value.
During Simultaneous Saccharification and Fermentation, Is it possible to know the amount of sugar released into the system by the enzyme from biomass and the amount of sugar consumed by the yeast? If possible, how?
I need to calculate the ethanol yield (in g per g glucose consumed) from an SSF experiment so that I can easily compare the result with that of SHF.
Understanding algae responses to stress can help to improve our knowledge about algae adaptation strategies which can be used to engineer tolerant strains. Also, it can be used to manipulate culturing condition to yield the higher amount of secondary metabolites like carotenoid.
In most of the articles that I am reading it is not mentioned why is important understanding adaptation mechanisms. Are there any other applications other than what I stated?
I read an article saying that 66.07 g of NH4+ will be available in 1 litre of water if 1 mole of ammonium sulfate is introduced to water
But i presume that 36 g/lit of ammonium should be present but the above mentioned reference says that 66 g/lit. kindly clarify me
1mole of ammonium sulfate = 132 g/lit ( N= 14,H=1,S=32,O=16)
Ammonium sulfate when dissolved in aqueous solution produces two NH4+ ion i,e 2*18 = 36 gm.
I need to selectively isolate fungal cellulase/xylanase producers in a selective medium which supports both bacterial and fungal cellulase/xylanase producing organisms. Tetracycline, a broad spectrum antibiotic, has been shown to inhibit some fungal species. Sodium azide and cyclo-heximide can also prevent both bacterial and fungal growth. This condition is also applicable to some other common antibiotics. I need a more restrictive antibiotic with no known antifungal property so that I will not lose any chance of selecting the best fungal strain.
For 'fatty acid ethyl ester extraction from fish viscera' project, I'm using the enzymatic method to extract and hydrolyse the oil. In this case, I'm producing lipase from solid state fermentation using fungus. Which is later used for hydrolysis and transesterification as well. The solid state fermentation is carried out for 5 days.
Is there any other method to replace the enzymatic method. I wants to speed up the extraction process? Is there any type catalyst or other method which can be used as alternative.
I would be glad if anyone would help me in this or send me some reference. Thanks in advance.
I want to check the interaction between magnetic immobilized enzyme with the nano materials. What are be the reaction parameters should be fixed for this?
First off, eventually what I want to get is a close-packed, monolayer of polystyrene(PS) spheres at the air/water interface (Langmuir-Blodgett method). But unlike those mentioned in many references, my polystyrene spheres are not dispersed in ethanol or butanol, but rather they are dispersed in water. This complicates the method since the spheres in water cannot float upon the water sub-phase for the LB method.
Other than synthesis of polystyrene spheres from scratch, is there a way to replace the water media with ethanol?
Is there a difference in efficiency when using sodium bicarbonate or sodium carbonate for CO2 gas when growing photosynthetic bacteria in a closed bioreactor?
An article of someone using this for any photosynthetic bacteria or algae would be perfect.
I have searched dozens of papers with the mentioned methodologies for siderophores. I managed to determine which reagents were used, but lack information about concentrations, and volumes.
I am searching for alternatives to Atkins and Arnow methods (and Neiland's) for hydroxamate and cathecol-type siderophore screening.
Thanks in advance,
I am working on Carbon-dioxide sequestration by microalgae using coal-fired actual flue gas in photobioreactors. The flue gas is being used as it is (without any pre-treatment). I am studying the flue gas introduced heavy metals into the system (medium and/or biomass). Could anyone please throw some light, which heavy metals I should be focusing on when analyzing the samples in ICP-MS. I am looking for Ni, Cr, Cd, As,Pb but Mo,Sn, Rb are also seen. Is it a fine observation?
May I know is nanocrystalline cellulose will sink to the bottom? I have studied a paper which stated that unmodiefied NCC will form two layers (NCC and distilled water) and modified NCC will remained in suspension and form a milky suspension
I get two layers after centrifugation.
Btw, how am I going to dry the NCC? I do not have any freeze-drying equipment here. Only oven.
I am working on visual detection of alcohol by using immobilization of AXO (alcohol oxidase) in agarose matrix. The method which I am following is involve reaction of alcohol (source) with AOX in polymer matrix. By which generation of H2O2 occur and react with HRP to produce colour change to green to DARK green. But I am not getting the satisfactory results. Please suggest any other polymer matrix which I can use or any alteration in experiment. I am attaching the reference paper.
Hello! We did a small biodigester at home, it had two units: a recipient with 0.25L and a another variable volume recipient for gas storage. The biodigester starts up with 1.5kg of food waste, 1 kg of cow manure and 5L of water. The system seems to be good during adaptation time (we planned 15d for this and then to operate it in semicontinuous mode), pH measurements every three days was nearly to 7. Neverthless, 9 days after the start up we have to burn the biogas the because the storage recipient was too small, but... it didn't burnt.
We have an hypothesis about what was bad in our design: the (inoculum/substrate ratio) was to small (0.6 aprox.) and for food waste the recommended ISR must be over 2 for preventing the inhibition (food waste are easily biodegradable matter)
We are not sure about adaptation time or if we can burnt the biogas daily, but in this case the pressure maybe won´t be for flow through the tube. Maybe we must change the design or we are doing something bad during the start up?
Am trying to develop an enzyme hydrolysis protocol using bromelain. The specific activity of the bromelain enzyme is 4.5 U/mg protein (provided by the supplier).
My task is to hydrolyze a fish sample using an enzyme sample ratio of 1% (1 g of enzyme powder added to 100 g of fish).
However, I observed from literature that enzyme sample ratio is frequently expressed as U/100 g of sample.
Hence, how do I convert the 1% enzyme-sample ratio to U/100 g of fish?
I wanted to study the effect of 1 % nitrogen source on the enzyme production via Solid State Fermentation.
Which method is correct?
A). The 1% nitrogen source is determine based on the volume of moisture I provide
B). The 1% nitrogen source is determine based on weight of the solid substrate I wanted to use.
Does anyone have experience on this matter? TQ
I want to extract cellulose degrading enzymes from the insects salivary glands, guts tissues and gut symbiotic microbes (Like Bacteria and Protozoa). so, can any one will help me to find best protocols for that.
I m working on kinetic study of biodiesel production. my questions are as follows
1. I want to analyse the sample with HPLC so which concentration should i estimate, is it Triglyceride or FAME.
2. what are the standards generally used for the estimation for both TG and FAME.
3. After getting the concentrations how to estimate the rate constant.
4. can we estimate the gibbs free energy from calculated rate constant.
I was doing some research on ABE fermentation using bacterium Clostridium acetobutylicum.Before fermentation, deactivated bacteria cultures are stored at -80 °C. The thawed cells are then inoculated into 12 mL synthetic medium containing glucose (30 g/L) and Yeast Extract (5 g/L) in 15 mL Hungate tubes (pre-cultures). Cells are then grown under an aerobic conditions for 48 h at 37 °C, thereafter they are transferred into fermentation bottles.
While determining the pH stability of a an enzyme. I incubated the enzyme at pH range 3-10 for 72hrs.
I wish to ask, if it is sufficient to describe an enzyme which retains its activity at alkaline pH 10 as "alkaline stable" even though:
1- I did not test stability up to pH 14
2- that its optimum activity was pH 5.3 during assay.
Your kind advice and criticism are welcomed.
I'M working on the soil Enzymes. I need to to check the total reductase enzyme production and its activity produced by certain enzymes especially when the inoculum is converted to liquid media. Can anyone suggest to me a particular method or protocol to analyze the reductase enzyme production by the microbial community in the media?
I need commercial grade Cellobiose dehydrogenase (CDH). Does anyone have the information about any company/organization/supplier who can supply commercial grade CDH?
Now I need to design a transfer function for my bioreactor. The controllable parameters pH, DO, Speed, Temperature available in the system. I need to control all the parameters.
Is it possible to add more parameters within a single transfer function?
If yes, Then how i control the parameters separately?
More over i have a plan to design a MRAC for that system.
I am currently running an MFC at OCV and I want to start applying loads on it. What really determines the starting resistance to be applied to the cell? I read a lot of literature that start with 1kohms and some as low as 10 ohms and I have done this in this past but is there another specific criteria?
In bioreactors, I maintain a low pH via combination of cell metabolism and base addition. In shake flask, base addition is not possible, and I've been looking for a suitable, biologically compatible buffer system for a pH between 3 and 4. Most biological buffers are designed for much higher pH ranges.
I've tried sodium citrate/citric acid, but my cells grow poorly and lyse.
Any suggestions? I plan to try a glycine-HCl system, but I'm not too confident about it, the HCl doesn't sound cell-culture friendly.
I am working on phytase production by a B. subtilis strain. We are going to scale up the production using a NBS BioFlo 310 Bioreactor. We are going to use NBS EX-2000 Gas Analyzer for measuring O2/CO2 from the bioreactor exhaust, but unfortunately, we are having difficulty working with this equipment. Although, the air enters and exits from the machine, but its flow-meter doesn't work and the results aren't satisfactory! Also, how can I make sure that the machine is working properly?
Thank you in advance!
My enzyme is cellulase from A. niger
please guide me how can be used and how much needed for fermentation?
is it based on volume of fermentation medium or substrate (biomass)?
if the enzyme inoculation related to FPU how can convert it to gram/liter?
ammonium is nitrified mostly to nitrate and most phosphates are removed
during the aerobic period (aeration), where the accumulated nitrate
is completely denitrified during the anoxic period (non-aeration), and phosphorus (P) is taken up.
P is found in wastewater as phosphates (orthophosphates, condensed
phosphates, organic phosphate fractions), and it can be eliminated either by
precipitation and/or adsorption, or by luxury uptake. Luxury uptake of P is accomplished by the introduction of an anaerobic phase in the wastewater treatment line ahead of the aerobic phase and recycling of sludge through the anaerobic and aerobic phase. Exposing mixed liquor to an anaerobic/aerobic sequence selects phosphate accumulating microorganisms (PAOs) due to a competition between PAOs and other aerobic organisms. This competition mechanism is based on a complete anaerobic uptake of the lower fatty acids by the polyP organisms (i.e., PAOs), which assures that in the aerobic phase, no fatty acids are left. The polyP organisms use the stored internal substrate during aerobic conditions while other aerobic organisms are lacking substrate. This process is usually referred to as the enhanced biological phosphorus removal (EBPR) process. EBPR process can be established in MBR treatment unit by operating it in intermittent aeration mode.
Intermittently aerated MBR can achieve nitrogen and phosphorus removal
by a simultaneous nitrification and denitrification, P-uptake and P-release in
the same reactor in accordance with time cycle of aeration and non-aeration.
However, even though intermittent aeration was successful in removing nitrogen, P removal was difficult to achieve at a higher level This is probably due to the inhibition by nitrate. In the anaerobic stage, nitrate reduces phosphate release, and in the aerobic stage it diminishes its uptake.
Denitrification has more capability than phosphorus release with respect to
the competition of substrate. This is because nitrate will be utilized as a final electron acceptor in the growth of non-polyP heterotrophs. Thereby, the amount of substrate available for polyP organisms is reduced and hence the removal of phosphorus is lowered. There are some studies that confirm the ability of polyP organisms for denitrification, however, not all PAOs can use nitrate as an electron acceptor.
I'm looking for some help in setting up a Bioreactor system for cultures of Cupriavidus necator which will be gas-fed growths. My problem comes in determining the flow rates that will be required for the gases. Without some idea of the necessary flow rates suitable to feed a culture, I cannot determine which Mass Flow Controller's I will need to purchase.
So far my search for information has only revealed various ratios of gases used previously, and that the rates must be varied in order to support the growths. What I need to know is the ratio of gas flow to culture size, so I can calculate the range of flow control I will need for my system in relation to the vessel size, for Air, Oxygen, Nitrogen and Carbon dioxide.
Does anyone know this information? Or can direct me to some papers/journals/books etc that can give me some idea? Or even have experience in Cupriavidus necator cultures?
Any assistance will be very welcome. Thank you.
We are interested to use the Aber Futura Biomass probe (Dielectric spectroscopy) to measure the capacitance data of E.Coli and also scanning data of E.coli cell parameters (Cole-Cole alpha,Cell Diameter,Biovolume, Conductivity etc...). We are using bacterial mode(Default: 1.1MHz) with Polarisation OFF but we couldn't able to measure the capacitance data using default mode. Our offline data suggested that cells are growing well. Anyone can help us to solve this issue.
I just began working with E. coli K-12 for use as an oxygen scavenger in my reactors. I'm growing them on glucose, but since glucose is fermented I expect it to be quickly depleted in my reactor since I cannot reinject for reasons I won't go into. Once their food source is depleted, they'll no longer be able to reduce the O2 that periodically enters. I'd like to give E. coli a non-fermentable substrate that requires O2 as an electron acceptor. This will maintain a low level of continuous growth as O2 slowly leaks into my reactor since the cells can only grow when O2 is present. Can someone give me a short list of electron donors that E. coli can grow on with O2, but not without?
i am currently fermenting pichia and I am having issues with contamination. A red film keeps appearing in my solution after i inoculate it. instead of going acidic overtime the solution becomes basic. I have made new seed stocks which were grown in zeocion. Using the new seed stocks still leads to contamination.
I like to study the barotolerance of few bacterial strains by applying high pressure. In the Bioreactor pneumatic pressure is applied. Can anyone suggest me high pressure resistive materials to inoculate cultures and incubate in the reactor? Similar studies has used sterile plastic bags, hungate tubes, blood pouches were they have applied hydraulic pressure. The material should withstand high pneumatic pressure.
We are trying to find the best stop solution for in vitro microbiota fermentation that does not interfere with SCFA readings. So far I've seen KOH, CuSO4, Na3PO4 used as stop solution. If you have used any of these or any other stop solutions, what is your opinion? Thank you very much.
I have tried to increase molecular weight of poly lactic acid of lower molecular weight by chain extension with di dissociates . It give me weight average molecular weight of 200000 Da. I would like to know does there is any other method to get ultra high molecular weight PLA.
I need to know the conversion of density to mg/l and how much ml needed to prepare 100mg/l of solution of tert. butanol in water. The density of tert.butanol is 0.775g/ml, can anyone suggest this calculation.
I'm currently conducting research on the production of xylanase, pectinase and protease via solid state fermentation. The crude enzyme I harvested from each set of SSF is my primary source of each enzyme I mentioned earlier.
From my literature review it is okay to use sodium acetate buffer for the extraction of xylanase and pectinase. How about protease? does sodium acetate buffer suitable for the leaching out of protease from the SSF?
Currently I'm doing research on production of hydrolytic enzymes via SFF. Does anyone know the best way to store crude enzyme while maintaining its freshness in term of enzyme activity. And how long can it maintain?
I am unable to have a definite peak in the chromatogram of the five monomeric sugar and cellobiose analysis using HPLC. All five monomeric sugars, except Glucose, forms tailing peaks while Cellobiose is not detected. This tailing peaks caused overlapping when all sugar standards were run. My sugars and cellobiose were either from Merck or Sigma.
HPLC conditions are well stated. Other details are:
The brand and model of HPLC used: -HPLC Type: Fisher Scientific Thermofisher
Size of column: -Product name: APS-2 Hypersil
Diameter(mm): 250 x 4.6
-Particle size: (micron-N-)
We are trying to make anaerobic fermentation media from scratch. However, we noticed that hemin precipitated in the bottom of the media. Is this normal? If not, is there any way to dissolve hemin? Thanks!
I am currently conducting a research into fungal enzymes involved in glycosyl hydrolysis. I am to select one of three organisms for enzymes production. The activity of the enzyme produced by the best of these three organisms is twice the second best and three times the least. However, when I used the same enzyme units (30FPU) for the three organism in a target hydrolysis, enzymes from the other two organisms (those with lower activities) had higher sugar yields (10% total sugar yield more than the best organism). Of course, I thought that the other two organisms might posses some other complementary enzymes which act in synergy to produce a higher sugar yield but I am concerned that they however require a higher volume of crude enzymes or some expensive enzyme concentration mechanisms that will rather make the hydrolytic process non cost effective. I urgently need a decisive guide about this.
Basically I work on solid state fermentation of fungus and find it really difficult to confirm if my seed cultures are pure.
the pattern of consumption of amino acid is depend on yeast strain.
but is there any one knows the availability of oxygen also cause to consumed more amino acid or not?
I may not know enough to know if this is even possible, but if it were: who, what industry, where would be likely to be working on something like this? I am sure there would be more interest in this kind of thing in countries who acknowledge the importance of LAB fermented foods for physical and mental wellness.
I need to observe the viscosity in a bioreactor on-line. Does anybody know how to do so? Is there any device/ any probe to measure viscosity?
I deal with production of Lipase from Candida sps. (CALB). The fermentation has been recently scaled up to a 3L fermentor. The problem that I face now is the fluctuating O.D values of the broth measured through a period of 48 hours. I cannot seem to point out the actual cause of the decline in O.D.
I need to extract this compounds from my biodiesel sample in order to characterize them in HPLC tests. Any suggestions are welcome.
I am working on separation of biosurfactant from fermentation broth by using the three phase partitioning method. In this method biosurfactant gets partitioned in t-butanol phase.
I want to bind plant cells together with biopolymer (biocompatible) with a very simple protocol in order to not induce too much stress to the cells.
I am working on enzyme production and want to study its kinetics. To stop an enzymatic reaction I need to add KCN. Due to potential toxicity, I don't want to use KCN, so please suggest some other enzyme inhibitors that have little or no toxicity..
My shake flask experiment when lactobacillus delbreuckii lactis ATCC4797 grown in media containing lactose and casein hydrolysate, in which trace quantities of calcium carbonate added as neutralizing agent. We observed increase in pH from 6.72 to 8.73 after 46 hours. Cell OD is also found to increasing ironically. I would like to put before this forum to what would be the possible cause of increasing pH whereas the with the same organism and media components without calcium carbonate were showing decreased pH as is expected.
I would like to produce gel filament of cell entrapped in polymer solution. But when I mix the suspension with the polymer solution, a pre-gel is formed and air bubbles are also entrapped in the mixture. I've already tried to removed the air bubbles by vacuuming but it takes very long time and isn't good for cell viability. Any idea how to remove the air bubbles without causing cell damaging?
Conventional enzyme screening methods are often time consuming and laborious. There must be some alternative way to do this. Can anybody suggest a reliable method for this?
When we plot glucose consumption, ethanol production or growth curve in a fermentation process, most of the time we can not get a smooth line connecting the data points. I found some articles e.g.:
1. Alfenore et al. (2002) Appl. Microbiol. Biotechnol. 60:67–72
2. da Cruz et al. (2003) J. Inst. Brew. 109(4): 349–355
These authors seems to use trend line on their graph, since I noticed that the line are not exactly connecting the data points.
Is there anyone know that we may do that? if the answer is yes , can anyone suggest what regression used for those curve and refer me to any reference that mentioned this?
Thank you in advance.
I did the experiment for the determination of reducing power by oyaizu 1986 method and found absorbance values but how to do the calculation to determine reducing power or the extract? do we have any formula? Or the absorbance values corresponds to reducing power? What unit should I use?
Does anybody have any ideas about water binding capacity and water holding capacity? Are there any differences between water binding capacity and water holding capacity? And how to measure them?
If we want to relate changes in NADH/NAD ratio to increase/decrease in production of certain metabolite in a bacteria, then what range of ratio changes will be considered significant?
I am performing the cellulase + cellobiase activity checking.
For cellulase, I managed to check its activity in FPU/ml as described by Ghose, 1987.
Can anyone tell me the rapid, simple method to check the cellobiase activity?
Any paper to refer?
Bioprocess industries are facing number of challenges like expensive process, new technology and sophistication of instrumentation and control etc.
I am working on bioethanol production. How can I quantify the reducing sugars percentage (glucose, xylose, arabinose,galactose, etc.) by using HPLC, after pretreatment, and what are the column conditions for the analysis?
I´m looking for the best method to concentrate 400L - 800L of fermentation:
- Centrifugation (different industrial machines)
- Lyophilization ?
- Any other suggestion?
Process analytical technology is applied in On-line HPLC which is used to measure the purity of biopharmaceuticals. The main keyword used in this article is POOLING. i.e. Online HPLC offers a feasible approach for analysis that can facilitate real-time decisions for column pooling. Feasibility of using ONline HPLC system for REAL TIME POOLING of process chromatography column. In the case of high resolution separation where a part of peak is being collected to pool the product and pool out the impurities.. Does anyone know what does the word pool refers to?