Production lactic acid

CAS Registry No. 50-21-5 (DL-lactic acid) 79-33-4 (L-lactic acid) 10326-41-7 (D-lactic acid) 

Carl Wilhelm Scheele was the first to discover lactic acid in 1780. Since then, lactic acid has been industrially produced using the fermentation process, with the earliest technology 

L-lactic acid can be metabolized by enzyme action in the human body. However, the intake of D-lactic acid should be undertaken with caution 100 mg/kg of body weight is the daily maximum stipulated for adult humans, and strictly no D-lactic acid and DL-lactic acid should be present in infant food, according to the guidelines of the FAOAVHO (Deshpande, 2002). Although the human body does not produce an enzyme for D-lactic acid, a small intake is considered safe because the high solubility of D-lactic acid promotes hydrolysis in the body fluid subsequently removed by the body s excretion system. 

Lactobacillus acidophilus produce D-lactic acid and a mixture of the two stereoisomers concurrently (Nampoothiri et al., 2010). Some species of Lactobacillus have the ability to undergo fermentation using a variety of saccharines, as listed in Table 2.2. 

Although the bacterial organism and the carbohydrate are the essential components in the fermentation process, the organism requires a variety of nutrients to ensure its healthy functionality, including B-vitamins, amino acids, peptides, minerals, fatty acids, nucleotide bases and carbohydrates. The amounts are species-dependent and the source of these nutrients can be agricultural derivatives, such as corn steep liquor and yeast extract. Lactic acid bacteria are heterotrophic, which mean that they lack biosynthetic capabilities (Reddy et al., 2008). The addition of complex nutrients can significantly increase the cost of production. However, a higher purity lactic acid is produced. 

By contrast the fermentation process uses safe renewable feedstocks 

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Fig. 1. Conventional process for lactic acid production from dextrose, molasses, or whey.

Figure 1 shows the time course of lactic acid production through SSF in a batch reactor of IL volume for an initial load of 10 g/1 bean curd refuse with or without pretreatment using 0.1 mol/1 HCl aqueous solution with heating at 121C for 30 min. The finally attained lactic acid yield on a carbon basis... 

Effect of Na-alginate and bead diameter on lactic acid production from pineapple waste using immobilized Lactobacillus delbrueckii ATCC 9646... 

Fig. 2. Effect of sodium alginate concentration on lactic acid production...

A similar trend is also observed for the production of lactic acid in Fig.4. Maximum lactic acid concentration is attained for the 1mm bead diameter with a yield of 30.27 gL". A further increase in the bead diameter to 5mm results in a decrease of lactic acid production to 17.65 gL". Abdel-Naby et al. (1992) had studied the effect of bead diameter for lactic acid production and found the optimum lactic acid yield was obtained using a 2mm bead diameter. Lactic acid production increased as bead diameter continues to decrease. 

Effect of bead diameter on lactic acid yield is clearly revealed in Fig.6. The optimum bead diameter for the fermentation of lactic acid for cell entrapped in Ca-alginate is 1.0mm with a yield of 30.27 gL and 96.7%. Increasing bead diameter beyond this value did not improve lactic acid production. Smaller bead diameter yields more lactic acid production, due to an increase in the surface volume ratio [9]. A further increase in bead diameter to 5.0mm results in a decrease of lactic acid production to 17.65 gL or 50.7%. 

Decreased cerebral blood flow, resulting from acute arterial occlusion, reduces oxygen and glucose delivery to brain tissue with subsequent lactic acid production, blood-brain barrier breakdown, inflammation, sodium and calcium pump dysfunction, glutamate release, intracellular calcium influx, free-radical generation, and finally membrane and nucleic acid breakdown and cell death. The degree of cerebral blood flow reduction following arterial occlusion is not uniform. Tissue at the... 

Simultaneous and continuous measurements of extracellular pH, potassium K+, and lactate in an ischemic heart were carried out to study lactic acid production, intracellular acidification, and cellular K+ loss and their quantitative relationships [6, 7], The pH sensor was fabricated on a flexible kapton substrate and the pH sensitive iridium oxide layer was electrodeposited on a planar platinum electrode. Antimony-based pH electrodes have also been used for the measurement of myocardial pH in addition to their application in esophageal acid reflux detection. 

Ohta T, Ogbonna JC, Tanaka H et al (1994) Development of a fermentation method using immobilized cells under unsterile conditions ethanol and L-lactic acid production without heat and filter sterilization. Appl Microbiol Biotechnol 42 246-260... 

Membrane-based separation, lactic acid production and, 14 120 Membrane biocompatibility, in hemodialysis, 26 823—824 Membrane bioreactors, 16 26 Membrane-bound enzymes, 10 338 Membrane cell process, 9 620 Membrane cells... 

Lactic acid is one of the major organic acids produced by fermentation. AimuaUy about 35 000 tonnes are produced this way [56]. The work on NF-based membrane fermentors for the production of organic acids has been started with the observation that lactic acid retention of RO membranes shows a strong pH-depen-dence [57-59]. For selective removal of lactic acid a low pFI is necessary, however, this reduces the lactic acid productivity to about 1 g Compared with UF-... 

Pharmacoiogy The exact mechanism of action of colchicine in gout is not known. Colchicine apparently exerts its effect by reducing the inflammatory response to the deposited crystals and also by diminishing phagocytosis. Colchicine diminishes lactic acid production by leukocytes directly and by diminishing phagocytosis and thereby interrupts the cycle of urate crystal deposition and inflammatory response that sustains the acute attack. 

Colchicine [Antigout Agent/Colchicum Alkaloid] Uses Acute gouty arthritis prevention of recurrences familial Mediterranean fever primary biliary cirrhosis Action -1- Migration of leukocytes X leukocyte lactic acid production Dose Initial 0.6—1.2 mg PO, then 0.6 mg ql-2h until rehef or GI SE develop (max 8 mg/d) do not r eat for 3 d /U 1-3 mg, then 0.5 mg q6h until rehef (max 4 mg/d) do not rqjeat for 7 d Prophylaxis PO 0.6 mg/d or 3-4 d/wk ... 

Tachycardia, skeletal muscle tremor, hypokalemia, increased hyperglycemia Lactic acid production, headache... 

Mechanism of Action An alkaloid that decreases leukocyte motility, phagocytosis, and lactic acid production. Therapeutic Effect Decreases urate crystal deposits and reduces inflammatory process. 

Shahbazi A, Li Y, Coulibaly S (2005) Lactic acid production from cheese whey, 1890 Joint Research and Extension Conference, New Orleans, 19-22 June, first Place Award of presentation competition of Association Research Director (ARD) and Association of Extension Administrator (ALA)... 

Gould, I.A. (1945) Lactic acid in dairy products. III. The effect of heat on total acid and lactic acid production and on lactose destruction. J. Dairy Sci., 28, 367-77. 

Rhizopus oryzae was immobilized in polyurethane foam cubes by Sun et al. -" The effects of the cube size on cell immobilization, cell growth and L(-i-)-lactic acid production were studied, limnobilization was accomplished by simple adsorption. The use of small cubes for R. oiyzae immobilization was very effective in increasing the productivity of L(-t-)-lactic acid by the immobilized cells. The inoculum size was effective for increasing the immobilization ratio (ratio of the number of cubes containing cells to the total number of cubes). We discussed mass transport problems of polyurethane foam and how the application of certain composite technologies mitigates this difficulty earlier in this chapter. 

Waste Acid Recovery via Purification Lactic Acid Production Recovery of Na-CO, from Trona... 

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