Alternative Methods of Lactic Acid Production

Alternative Methods of lactic Acid Productionlactic panelling is a hydroxycarboxylic corrosive, which is widely mapd in food, pharmaceutical, leather, cosmetic and material industries. It can be polymerized to biodegradable and biocompatible plastic, i.e. polylactic acid, which has environment-friendly and great potential for replacing petrochemical plastic. Industrially, it can be produced by either chemical synthesis or microbial agitation. Presently, virtually 90% of lactic acid was produced by lactic acid bacteria fermentation. Fermentative output signal has the advantage that by choosing a strain of LA bacteria producing simply one of the isomer and optically pure product. The widely used substrates for lactic acid action are pure sugar, which are expensive. It is as well possible to use ligno carrellulosic biomass, curiously by product or thieve materials from agriculture and industrial waste as substrates for fermentation. Therefore, the use of selection substrates , low-cost and raw materials lead thus of excess interest for lactic acid exertion. The present study the utilization of industrial wastes and lignocellulosic as an alternative substrate for lactic acid labor.Lactic acidLactic acid (2-hydroxy propionic acid) is a chemical compound that a role in several biochemical processes. It is a carboxylic acid with a chemical traffic pattern of C3H6O3. Lactic acid is chiral and has both optical isomers as shown in figure 1.Lactic acid is organic solvent that can dissolve in peeing but insoluble in other organic solvents. Other properties of lactic acid are presented in Table 1.Table 1. Physical properties of lactic acid. tiltChemical formulaC3H6O3Molecular weight90.08Acidity (pKa)3.85Melting pointL 53 CD 53 CD/L 16.8 CBoiling point82 C at 0.5 mm Hg122 C at 14 mm HgDissociation constant, Ka at 25 C1.37 x 10-4Heat of combustion, Hc1361 KJ/moleSpecific Heat, Cp at 20 C190 J/mole/ CSource Vickroy (1985)Lactic acid can be produced by ch emical synthesis or microbial fermentation. The chemical synthesis produced a racemic mixture of D, L lactic acid. Presently, or so 90% of lactic acid made by LAB fermentation and the remainder is produced synthetically by the hydrolysis of lactonitrile. The advantage of fermentation technologies is possible to use renewable resources as substrates, such as starch and cellulose in fermentative production. In figure 2 described the diagram of commercial uses and applications of lactic acid. Food applications reported for approximately 85% of the total lactic acid, while the nonfood industrial applications reported for only 15% of the demand.Alternative substrate for lactic acid productionIn fermentation process, lactic acid bacteria (LAB) need carbon source, essentially simple sugars and nitrogen source, as vital nutrients for their growths. The widely used substrates for lactic acid production are refined sugar, which are expensive. Therefore, attention has turned towards lignocel lulosic biomass and industrial wastes to provide a source of carbohydrate for lactic acid production.LignocellulosicLignocellulosic resources are generally considered to move an interesting and catchpenny(prenominal) raw material for microbial fermentation of lactic acid production, as they are renewable and cheap. A schematic diagram of the procedures for the dressing of lignocellulosic hydrolyzates is provided in figure 3.Wee and Ryu (cc9) reported the production of lactic acid from lignocellulosic, glucose and lignocellulosic hydrolyzates were used as the carbon source. The concentration of lactic acid decreases with increases in the dilution rate. Generally, the cell concentration obtained from lignocellulosic hydrolyzates media was approximately 10-15% lower than observed with glucose media. The lactic acid yields were provided at more than 0.90 gg-1 the result are shown in table 2.The lignocellulosic hydrolyzates have to be detoxified in order to reduce these inhibitory eff ects prior to fermentation, as some of the by-products released during the pretreatment (Mussatto and Roberto, 2004). Ruengruglikit and Hang (2003), reported the lactic acid production from lignocellulosic materials by R. oryzae. After an enzymatic hydrolysis and 48-h fermentation, lactic acid yields of 0.3 gg-1.Food wastesFood wastes, which are supplied at lower costs, high in moisture and rich in carbohydrates. They could be suitable alternative substrate for lactic acid production. The food wastes contain polysaccharides as well as various oligosaccharides.Ohkouchi and Inoue (2005) reported the production of lactic acid from food wastes. The subject of food wastes is shown in Table 3. The optimum pH for L (+)-lactic acid production by L. manihotivorans LMG 18011 was 5.0 and under these condition the L (+)-lactic acid was 19.5 g produced from 200 g food wastesKim et al. (2003) determined lactic acid production from food wastes by simultaneous saccharification fermentation technic al. The effect of food wastes concentration on lactic acid production as shown in figure 4.In figure 4, the highest yield was obtained from 65 g/L of food waste with a last-place lactic acid concentration of 44.3 g/L, while the highest lactic acid concentration of 79.7 g/L was obtained from 145 g/L of food waste.pineapple wasteMost of the work using starch, beet molasses and sugar cane as the fermentation media for lactic acid production. Recently, Uno (2003) used grape invertase to inviting the production of lactic acid utilizing pineapple syrup as substrate. The efficiency of lactic acid production has been an affect from various aspect and ability to use fruit waste.Idris and Suzana (2005) reported the liquid pineapple waste, it is feasible to use produce lactic acid by immobilized L. delbrueckii. The maximum lactic acid can be obtained when parameters initial pH of 6.5, temperature of 37 C and sodium alginate concentration at 2% with a bead diameter of 1 mm in diameter. The h ighest value of kinetic parameters are obtained at 37 C and initial pH 6.5 (Table 4 and Table 5).Recycled paper sludgeRecycled paper sludge is an industrial waste has high polysaccharides (mainly cellulose) content. The conversion of polysaccharides on sludge to be broken down into the monomers and released sugars to be fermented to lactic acid. The methods for conversion of a polysaccharide into the monomer consist of enzymatic and acid hydrolysis.Marques et al. (2008) studied the utilization of recycled paper sludge as an alternative substrate for lactic acid product. The maximum production of lactic acid was produced 73 g/L of lactic acid, maximum productivity of 2.9 g/L/h, with 0.97 g LA per g of carbohydrates on initial substrate. The fermentative parameters concerned the lactic acid production of all the cultivations in this work are presented in table 6.ConclusionsThe widely used substrates for lactic acid production are refined sugar, which are expensive. It is also possibl e to use lignocellulosic biomass, especially by product or waste materials from agriculture and industrial waste as substrates for fermentation. Therefore, the use of alternative, low-cost and raw materials become thus of special interest for lactic acid production. The ability to utilize this industrial wastes and lignocellulosic as alternative carbon sources for lactic acid production provide help reduce of environmental pollution problem and also reduce production costs.LITERATURE CITEDIdris, A. and W. Suzana. 2006. Effect of sodium alginate concentration, bead diameter, initial pH and temperature on lactic acid production from pineapple waste using immobilized Lactobacillus delbrueckii. Process Biochem. 41 1117-1123.Kim, K.I. , W.K. Kim, D.K. Seo, I.S. Yoo, E.K. Kim and H.H. Yoon. Production of lactic acid from food wastes Appl. Biochem. Biothnol. 101-108 637-647.Marques, S. , J.A.L. Santos, F.M. Grio and J.C. Roseiro. 2008. Lactic acid production from recycled paper sludge by simultaneous saccharification and fermentation. Biochem. Eng. 41 210-216.Mussatto, S.I. and I.C. Roberto. 2004. Alternatives for detoxification of diluted-acid lignocellulosic hydrolyzates for use in fermentative processes. Bioresour. Technol. 1-10.Nexant. 2008. Biotech Route to Lactic Acid/ Polylactic Acid. Available Sourcehttp//nexant.ecnext.com/coms2/summary_0255-130_ITMOhkouchi, Y. and Y. Inoue. 2006. Direct production of L(+)-lactic acid from starch and food wastes using Lactobacillus manihotivorans LMG18011. Bioresour. Technol. 97 1554-1562.Ruengruglikit, C. and Y.D. Hang. 2003. L(+) lactic acid production from corncobs by Rhizopus oryzae NRRL-395. Lebensm. Wiss. Technol. 36 573-575.Uno, T., Y. Ozawa, M. Ishikawa, K. Nakanishi and T. Kimura. 2003. Lactic acid production using two food processing wastes, canned pineapple syrup and grape invertase as substrate and enzyme. Biotechnol. Lett. 25 573-577.VickRoy, T.B. 1985. Lactic acid, pp. 761-776. In Blanch, H.W., S. Drew and D.I. C.Wang eds. Comprehensive Biotechnol. Vol. 3. Pergamon Press, Oxford.Wee, Y.J., J.N. Kim and H.W. Ryu. 2006. Biotechnological production of lactic acidand its recent applications. Food Technol. Biotechnol. 44(2) 163-172.Wee, Y.J. and H.W. Ryu. 2009. Lactic acid production by Lactobacillus sp. RKY2 in a cell-recycle continuous fermentation using lignocellulosic hydrolyzates as inexpensive raw materials. Bioresource Technol. 100 4262-4270.