3.1 Recovery and purification of microbial PHA Recovery and get high level purity of polyhydroxyalkamotes (PHAs) synthesized by bacterial species is the promise stair of the process efficiency in the fermentation system. This is the reason that many scientists and researchers have studied in this field for the production of this biodegradable polymers. The most excellent method should lead to a high purity and recovery level at a low production cost (Jacquel et al., 2008). 3.1.1 Solvent Extraction In the purification process of PHA, solvent extraction is one of the oldest and most extensively accepted techniques for recovery of PHA from the cell biomass. This technique is also used frequently in the laboratory because of its simplicity and …show more content…
Later, Lafferty and Hernzle (1978) were also studied these cyclic carbonic esters by with 1,2 propylene carbonate, they obtained 95% of the PHB from the cell mass in under extraction process carried out by them. Baptist (1962) also primarly utilized few solvent mixtures like chloroform/methanol and dichloromethane/ethanol. Later, Vanlautem and Gilain (1982) investigated extraction of PHA from R. eutropha with halogenated solvents like chloropropanes and chloroethanes. They found that solvents in which the functional carbon atoms are carrying as a minimum one chlorine atom and one hydrogen atom were given the best results. The employment of diols (1,2- propandiol: recovery 79%, purity 99.1%, 1400C), acetalized triols (glycerol formal: recovery 85%, purity 99.7%, 1200C), dicarboxylic or tricarboxylic acid esters (diethyl succinate: recovery 90%, purity100%, 1100C), or butyrolactone (recovery 90%, purity 99.5%, 1100C), as extracting agents were studied by Traussnig et al. (1990). Noda (1998b) of Procter & Gamble projected a method concerning, initially, a biomass treatment with a combination of PHA solvent and non-solvent, after that the unsolvable biomass is recovered, and lastly the removal of PHA solvent led to a liquid …show more content…
Recovery of PHB in chlorinated solvents was also studied by Ramsay et al. (1994). The best results were obtained by using acetone pretreatment along with solvent reflux about 15 min in methylene chloride or chloroform. Recovered PHB had 95% purity. Valappil et al. (2007a) carried out chloroform extraction and obtained Purity-92%; Yield-31% with Bacillus cereus SPV. Jiang et al. (2006) developed acetone extraction method for the extraction of mcl-PHA from Pseudomonas putida KT2440 they reported that almost all of the PHA could be recovered with no detectable loss of molecular weight when dry biomass was cleaned in 20 parts of methanol about 5 min pursued by Soxhlet extraction in 10 volumes of acetone for 5 h. The utilization of solvents demolishs the normal external features of PHA granules that is valuable in definite applications like the fabrication of strong fibers. But, contrary to some other recovery methods, solvent extraction do not degrade the polymer (Jacquel et al., 2008) also solvent extraction has undoubted advantages over the other extraction methods of PHA in order to
Every 5 minutes, a small amount of mixture was dissolved in acetone (0.5 mL) and was spotted onto a thin layer chromatography (TLC) plate, which contained an eluent mixture of ethyl acetate (2 mL) and hexanes (8 mL). The bezaldehyde disappearance was monitored under an ultraviolet (UV) light. Water (10 mL) was added after the reaction was complete, and vacuum filtrated with a Buchner funnel. Cold ethanol (5 mL) was added drop-by-drop to the dried solid and stirred at room temperature for about 10 minutes. Then, the solution was removed from the stirrer and place in an ice bath until recrystallization. The recrystallized product was dried under vacuum filtration and the 0.057 g (0.22 mmol, 43%) product was analyzed via FTIR and 1H NMR
The alcohol starting material, 2-methylcyclohexanol, was dehydrated through an E1 elimination by using of phosphoric acid as a catalyst. After a purification by simple distillation, which removed the alkene product and the by-product water from the reaction mixture, the methylcyclohexene products were analyzed by percent yield, boiling point, IR spectroscopy, and two chemical tests, Br2 in CCl4 and Jones test. By performing the simple distillation using pyrolysis, 85% of phosphoric acid and 2-methylcyclohexanol were added into the boiling flask, where the product from the collecting flask was condensed by the ice, and washed with the saturated sodium chloride. The weight of the product was determined and the percent yield of the product was
As shown in figure 2, the percentage of each isomeric alcohol in the mixture had been determined. The hydrogen atom on the carbon atom with the hydroxyl group appear at around 4.0 ppm for borneol and 3.6 ppm for isoborneol. The product ratio has been determined by integrating the peaks. A ratio of 6:1 for the Isoborneol/borneol ratio was expected and is validated by the calculations shown above, with isoborneol percentage at 83.82% and 16.17% of borneol. A CHCl3 group noted at around 7ppm and a CH2Cl2 at around 3.5ppm.
The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
Makadia HK. & Siegel SJ., 2011. Poly Lactic-co-Glycolic Acid (PLGA) as Biodegradable Controlled Drug Delivery Carrier. Polymers, 3, 1377-1397
called an active site. This active site is made by a few of the amino
Alkaline Phosphatase (APase) is an important enzyme in pre-diagnostic treatments making it an intensely studied enzyme. In order to fully understand the biochemical properties of enzymes, a kinetic explanation is essential. The kinetic assessment allows for a mechanism on how the enzyme functions. The experiment performed outlines the kinetic assessment for the purification of APase, which was purified in latter experiments through the lysis of E.coli’s bacterial cell wall. This kinetic experiment exploits the catalytic process of APase; APase catalyzes a hydrolysis reaction to produce an inorganic phosphate and alcohol via an intermediate complex.1 Using the Michaelis-Menton model for kinetic characteristics, the kinetic values of APase were found by evaluating the enzymatic rate using a paranitrophenyl phosphate (PNPP) substrate. This model uses an equation to describe enzymatic rates, by relating the
In conclusion, E. cava is a very interesting resource, due to the presence of unique phlorotannin derivatives with special bioactivities including ACE inhibitory activity. Ethanol enhances the extraction of phlorotannins specially dieckol from the brown seaweed E. cava. By contrast, in this study phloroglucinol derivative dieckol exhibited the strongest activity against ACE. With the results of this study we can suggest that the brown seaweed E. cava could be used in development of promising and potential functional food products. Moreover, it is expected that these findings will contribute to developing interests in basic research and potential applications of the phlorotannins in the relevant fields.
The actual amount of crude product was determined to be 3.11 grams. The percent yield of the crude product was determined to be 67.75 %. The actual amount of pure product formed was found to be 4.38 grams. The percent yield of the pure product was determined to be 95.42%. Regarding the thin layer chromatography, the line from the solvent front is 8 centimeters.
The purpose of this experiment was to learn and preform an acid-base extraction technique to separate organic compounds successfully and obtaining amounts of each component in the mixture. In this experiment, the separation will be done by separatory funnel preforming on two liquids that are immiscible from two layers when added together. The individual components of Phensuprin (Acetylsalicylic acid, Acetanilide, and Sucrose as a filler) was separated based upon their solubility and reactivity, and the amount of each component in the mixture was obtained. Also, the purity of each component will be determined by the melting point of the component.
Once the mixture had been completely dissolved, the solution was transferred to a separatory funnel. The solution was then extracted twice using 5.0 mL of 1 M
In this experiment, a mixture of three substances (benzoic acid, 2-naphthol, and 1-4 dimethoxybenzene) will be separated based off acidity strength using the liquid-liquid extraction technique through a separatory funnel. Benzoic acid and 2-napthol will be converted into ionic salts when reacting with their appropriate bases (sodium bicarbonate and sodium hydroxide). Both ionic salts will then form solids through the addition of acidic HCl. Neutral 1,4 – dimethoxybenzene forms a solid through the evaporation of ether. Each compound will then be purified through recrystallization, using the processes of dissolving the solid in either water or methanol, and isolating the solid through vacuum filtration. After a week of evaporation, the compounds will then be examined for both
Performing this experiment, we used the technique called Acid-Base extraction to isolate Eugenol, which is one of the main ingredients of clove oil. Acid-Base extraction is the most efficient method for isolating organic component; it is efficient because it purifies the acid and base mixture based on their chemical identities. We have seen throughout this experiment that acid and base play an important role, when it comes to solubility in water. Our basic knowledge of acid and base is acid is a proton donor and base is a proton acceptor. This ideology helps us to understand why organic compounds are not soluble in water. When compounds tend to be insoluble, we have to use acid and base reaction, to change its solubility. The changes that occurred
Cellulose is an abundant polysaccharide consisting of a β-1, 4 linkage of D-glucose [1,3]. There is an array of applications for cellulose, including, but not limited to: biofuels, reinforcement agents, thickeners, dietary fiber, and even wound care. As of late, cellulose, as a waste product, has been in high demand as a reinforcement agent in synthetic, petroleum-based polymer matrices (petroleum based plastics) [3]. Cellulose I has good flexibility, it is abundant in nature and also biodegradable. Because of its fiber- like structure, it has been compared to carbon nanotubes (CNT’s) [3].
Preparation of Ethanol and Ethanoic Acid Introduction to report ---------------------- This report contains 5 practical experiments to produce ethanoic acid from ethanol. The first practical is the preparation of ethanol from glucose using yeast during the process of fermentation; this has been demonstrated in class. In this practical the glucose is converted into ethanol and carbon dioxide by respiratory enzymes from the yeast. The ethanol solution will be between 5-15% and the ethanol will be separated from the yeast by filtering.