共查询到20条相似文献,搜索用时 0 毫秒
1.
Young-Jung Wee Jin-Nam Kim Jong-Sun Yun Hwa-Won Ryu 《Biotechnology and Bioprocess Engineering》2005,10(1):23-28
Lactic acid is a green chemical that can be used as a raw material for biodegradable polymer. To produce lactic acid through
microbial fermentation, we previously screened a novel lactic acid bacterium. In this work, we optimized lactic acid fermentation
using a newly isolated and homofermentative lactic acid bacterium. The optimum medium components were found to be glucose,
yeast extract, (NH4)2HPO4, and MnSO4. The optimum pH and temperature for a batch culture ofLactobacillus sp. RKY2 was found to be 6.0 and 36°C, respectively. Under the optimized culture conditions, the maximum lactic acid concentration
(153.9 g/L) was obtained from 200 g/L of glucose and 15 g/L of yeast extract, and maximum lactic acid productivity (6.21 gL−1h−1) was obtained from 100 g/L of glucose and 20 g/L of yeast extract. In all cases, the lactic acid yields were found to be
above 0.91 g/g. This article provides the optimized conditions for a batch culture ofLactobacillus sp. RKY2, which resulted in highest productivity of lactic acid. 相似文献
2.
We isolated a novel lactic acid bacterium from a Korean traditional fermented food, soybean paste. The newly isolated strain,
dubbed RKY2, grew well on glucose, sucrose, galactose, and fructose, but it could not utilize xylose, starch, or glycerol.
When the partially amplified 16S rDNA sequence (772 bp) of the strain RKY2 was compared with 10 reference strains, it was
found to be most similar toLactobacillus pentosus JCM 1588T, with 99.74% similarity. Therefore, the strain RKY2 was renamedLactobacillus sp. RKY2, which has been deposited in the Korean Collection for Type Cultures as KCTC 10353BP.Lactobacillus sp. RKY2 was found to be a homofermentative lactic acid bacterium, because its end-product from glucose metabolism was found
to be mainly lactic acid. It could produce more than 90 g/L of lactic acid from MRS medium supplemented with 100 g/L of glucose,
with 5.2 g L−1 h−1 of productivity and 0.95 g/g of lactic acid yield. 相似文献
3.
A newly isolated sucrose-tolerant, lactic acid bacterium, Lactobacillus sp. strain FCP2, was grown on sugar-cane juice (125 g sucrose l−1, 8 g glucose l−1 and 6 g fructose l−1) for 5 days and produced 104 g lactic acid l−1 with 90% yield. A higher yield (96%) and productivity (2.8 g l−1 h−1) were obtained when strain FCP2 was cultured on 3% w/v (25 g sucrose l−1, 2 g glucose l−1 and 1 g fructose l−1) sugar-cane juice for 10 h. Various cheap nitrogen sources such as silk worm larvae, beer yeast autolysate and shrimp wastes
were also used as a substitute to yeast extract. 相似文献
4.
Kotzamanidis Ch. Roukas T. Skaracis G. 《World journal of microbiology & biotechnology》2002,18(5):441-448
Production of lactic acid from beet molasses by Lactobacillus delbrueckii NCIMB 8130 in static and shake flask fermentation was investigated. Shake flasks proved to be a better fermentation system for this purpose. Substitution of yeast extract with other low cost protein sources did not improve lactic acid production. The maximum lactic acid concentration was achieved without treatment of molasses. A Central Composite Design was employed to determine the maximum lactic acid concentration at optimum values for the process variables (sucrose, yeast extract, CaCO3). A satisfactory fit of the model was realized. Lactic acid production was significantly affected both by sucrose–yeast extract and sucrose–CaCO3 interactions, as well as by the negative quadratic effects of these variables. Sucrose and yeast extract had a linear effect on lactic acid production while the CaCO3 had no significant linear effect. The maximum lactic acid concentration (88.0 g/l) was obtained at concentrations for sucrose, yeast extract and CaCO3 of 89.93, 45.71 and 59.95 g/l, respectively. 相似文献
5.
Ram horns are a waste material from the meat industry. The use of ram horn peptone (RHP) as a supplement for lactic acid production was investigated using Lactobacillus casei. For this purpose, first, RHP was produced. Ram horns were hydrolysed by treating with acids (3 M H2SO4 and 6 M HCl) and neutralizing the solutions to yield ram horn hydrolysate (RHH). The RHH was evaporated to yield RHP. The amounts of protein, nitrogen, ash, some minerals, total sugars, total lipids and amino acids of the RHP were determined and compared with a bacto-tryptone from casein. When the concentrations (1–6% w/v) of the RHP were used in bacterial growth medium as a supplement, 2% RHP (ram horn peptone medium) had a maximum influence on the production of lactic acid by L. casei. The content of lactic acid in the culture broth containing 2% RHP (43 g l–1) grown for 24 h was 30% higher than that of the control culture broth (33 g l–1) and 10% higher than that of 2% bacto-tryptone (39 g l–1). RHP was demonstrated to be a suitable supplement for production of lactic acid. This RHP may prove to be a valuable supplement in fermentation technology. 相似文献
6.
Biotechnological production of l(+)-lactic acid from wood hydrolyzate by batch fermentation of Enterococcus faecalis 总被引:1,自引:0,他引:1
The inhibition of lactic acid fermentation by wood hydrolyzate was decreased (approx. 20%) by adaptation of Enterococcus faecalis RKY1 to wood hydrolyzate-based medium whereby lactic acid productivity and cell growth were enhanced by 0.5 g l(-1) h(-1) and 2.1 g l(-1), respectively. When the diluted or concentrated wood hydrolyzate (equivalent to 25-100 g glucose l(-1)) was supplemented with 15 g yeast extract l(-1), 24-93 g lactic acid l(-1) was produced at a rate between 1.7 g l(-1) h(-1) and 3.2 g l(-1) h(-1). 相似文献
7.
Following the application of several molecular techniques strain R 19c, isolated from sausage by Reuter in 1970 and deposited at the DSMZ as Lactobacillus sp., has been identified as pertaining to a new species. It showed singular ISR-DdeI and ISR-HaeIII profiles that allowed its differentiation from 68 lactic acid bacteria reference strains analyzed. Phylogenetic analysis based on 16S rRNA gene sequences places this strain in the genus Lactobacillus within the Lactobacillus alimentarius group. Species L. versmoldensis is the closest phylogenetic neighbor with 96.3% sequence similarity. DNA-DNA hybridization experiments confirmed the independent status at species level of this strain. Species-specific primers for PCR detection of this new species have been developed. Phenotypically it can be distinguished from the closest relative L. versmoldensis by several traits such as the peptidoglycan type (L-Lys-Gly-D-Asp), acid production from L-rhamnose, D-mannitol and L-fucose and its inability to ferment d-galactose, d-melibiose and d-sucrose. The name Lactobacillus tucceti sp. nov. is proposed with strain R 19c(T) (=DSM 20183(T)= CECT 5920(T)) as the type strain. 相似文献
8.
S. S. Kanwar B. S. Chadha H. K. Tewari V. K. Sharma 《World journal of microbiology & biotechnology》1995,11(6):687-688
Both free and immobilized cells of Sporolactobacillus cellulosolvens, in continuous culture on molasses (50 g sugar 1-1) at 40°C, had maximum lactic acid productivities of 0.03 and 0.06 mol l-1 h, at dilution rates of 0.27 and 0.25 h-1, respectively.S.S. Kanwar is with the Department of Biotechnology, Guru Nanak Dev University, Amritsar-143 005, India; B.S. Chadha is with the Department of Microbiology, Guru Nanak Dev University, Amritsar-143 005, India. H.K. Tewari and V.K. Sharma are with the Department of Microbiology, Punjab Agricultural University, Ludhiana-141 004, India. 相似文献
9.
Production of the anti-listerial bacteriocin, pediocin, by lactic acid bacteria (LAB) transformed with the cloning vector pPC418 (Ped+, 9.1 kb) was influenced by composition of media and incubation temperature. Maximum pediocin production, tested against Listeria innocua, by electrotransformants of Lactococcus lactis ssp. lactis was measured in tryptone/lactose/yeast extract medium after 24 h growth at 30 °C, while incubation at 40 °C was optimum for Ped+ transformants of Streptococcus thermophilus and Enterococcus faecalis. The amount of pediocin produced by S. thermophilus in skim milk and cheese whey supplemented with 0.5% yeast extract was estimated as 51000 units ml–1 and 25000 units ml–1, respectively. Pediocin production remained essentially unchanged in reconstituted skim milk or whey media diluted up to 10-fold. The results demonstrate the capacity of recombinant strains of LAB to produce pediocin in a variety of growth media including skim milk and inexpensive cheese whey-based media, requiring minimum nutritional supplementation. 相似文献
10.
A.E. Ghaly M.S.A. Tango N.S. Mahmoud A.C. Avery 《World journal of microbiology & biotechnology》2004,20(1):65-75
Continuous mix batch bioreactors were used to study the kinetic parameters of lactic acid fermentation in microaerated-nutrient supplemented, lactose concentrated cheese whey using Lactobacillus helveticus. Four initial lactose concentrations ranging from 50 to 150 g l–1 were first used with no microaeration and no yeast extract added to establish the substrate concentration above which inhibition will occur and then the effects of microaeration and yeast extract on the process kinetic parameters were investigated. The experiments were conducted under controlled pH (5.5) and temperature (42 °C) conditions. The results indicated that higher concentrations of lactose had an inhibitory effect as they increased the lag period and the fermentation time; and decreased the specific growth rate, the maximum cell number, the lactose utilization rate, and the lactic acid production rate. The maximum lactic acid conversion efficiency (75.8%) was achieved with the 75 g l–1 initial lactose concentration. The optimum lactose concentration for lactic acid production was 75 g l–1 although Lactobacillus helveticus appeared to tolerate up to 100 g l–1 lactose concentration. Since the lactic acid productivity is of a minor importance compared to lactic acid concentration when considering the economic feasibility of lactic acid production from cheese whey using Lactobacillus helveticus, a lactose concentration of up to 100 g l–1 is recommended. Using yeast extract and/or microaeration increased the cell number, specific growth rate, cell yield, lactose consumption, lactic acid utilization rate, lactic acid concentration and lactic acid yield; and reduced the lag period, fermentation time and residual lactose. Combined yeast extract and microaeration produced better results than each one alone. From the results it appears that the energy uncoupling of anabolism and catabolism is the major bottleneck of the process. Besides lactic acid production, lactose may also be hydrolysed into glucose and galactose. The -galactosidase activity in the medium is caused by cell lysis during the exponential growth phase. The metabolic activities of Lactobacillus helveticus in the presence of these three sugars need further investigation. 相似文献
11.
Lactobacillus helveticus grown in milk with pH control at 6.2 had a slower growth rate (=0.27 h–1) and produced less exopolysaccharide (49 mg l–1) but increased lactic acid production (425 mM) compared to cultures without pH control (=0.5 h–1, 380 mg exopolysaccharide l–1, and 210 mM lactate), respectively. Both cultures displayed a mixed-acid fermentation with formation of acetate, which is linked not only to citrate metabolism, but also to alternative pathways from pyruvate. 相似文献
12.
Spiros Paramithiotis Aggeliki Sofou Effie Tsakalidou George Kalantzopoulos 《World journal of microbiology & biotechnology》2007,23(10):1417-1423
The aim of this study was to assess the mode of carbohydrate catabolism by lactic acid bacteria isolated from traditional
sourdoughs, as well as to study their effect on the metabolites produced. For this purpose, single cultures of the heterofermentative
lactic acid bacteria Lactobacillus sanfranciscensis, Lactobacillus brevis, Weissella cibaria, and the homofermentative Lactobacillus paralimentarius and Pediococcus pentosaceus were grown in liquid media containing glucose, fructose, maltose and sucrose, either as a single carbon source or in combination
with glucose. Carbon catabolism and the production of metabolites were determined by HPLC analysis. W. cibaria could ferment all carbon sources, L. sanfranciscensis, L. paralimentarius and P. pentosaceus could not ferment sucrose, while L. brevis could only ferment maltose. The presence of glucose did not influence the utilization of fructose and maltose by L. sanfranciscensis, while it repressed the fermentation of fructose, maltose and sucrose by W. cibaria, and fructose and maltose by L. paralimentarius and P. pentosaceus. Moreover, L. sanfranciscensis and L. brevis could obtain extra ATP through the reduction of fructose to mannitol, which favored the production of acetic acid against
ethanol. The utilization of fructose as an electron acceptor has a decisive effect on the prevailing of L. sanfranciscensis and L. brevis in spontaneously fermented sourdough and in the scarce appearance of the other lactic acid bacteria studied. 相似文献
13.
Enrique Cubas-Cano Cristina González-Fernández Mercedes Ballesteros Elia Tomás-Pejó 《Biotechnology progress》2019,35(1):e2739
Lactic acid is a versatile chemical that can be produced via fermentation of lignocellulosic materials. The heterolactic strain Lactobacillus pentosus CECT 4023 T, that can consume glucose and xylose, was studied to produce lactic acid from steam exploded wheat straw prehydrolysate. The effect of temperature and pH on bacterial growth was analyzed. Besides, the effect of oxygen on lactic acid production was tested and fermentation yields were compared in different scenarios. This strain showed very high tolerance to the inhibitors contained in the wheat straw prehydrolysate. The highest lactic acid yields based on present sugar, around 0.80 g g−1, were obtained from glucose in presence of 25%, 50%, and 75% v v−1 of prehydrolysate in strict anaerobiosis. Lactic fermentation of wheat straw hydrolysate obtained after enzymatic hydrolysis of the prehydrolysate yielded 0.39 g of lactic acid per gram of released sugars, which demonstrated the high potential of L. pentosus to produce lactic acid from hemicellulosic hydrolysates. Results presented herein not only corroborated the ability of L. pentosus to grow using mixtures of sugars, but also demonstrated the suitability of this strain to be applied as an efficient lactic acid producer in a lignocellulosic biorefinery approach. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2739, 2019 相似文献
14.
Pyung Cheon Lee Woo Gi Lee Sang Yup Lee Ho Nam Chang Yong Keun Chang 《Biotechnology and Bioprocess Engineering》2000,5(5):379-381
Anaerobiospirillum succiniciproducens requires expensive complex nitrogen sources such as yeast extract and polypeptone for its growth and succinic acid production.
It was found thatA. succiniciproducens was able to grow in a minimal medium containing glucose when supplemented with corn steep liquor (CSL) as the sole complex
nitrogen source. The concentration of CSL had a significant effect on the glucose consumption byA. succiniciproducens. When 10–15 g/L of CSL was supplemented, cells were grown to an OD660 of 3.5 and produced 17.8 g/L succinic acid with 20 g/L glucose. These results are similar to those obtained by supplementing
yeast extract and polypeptone, thereby suggesting that succinic acid can be produced more economically using glucose and CSL. 相似文献
15.
Lactic acid bacteria (LAB) are important members of the human vaginal microbiota and their presence is considered beneficial.
However, little is known about native vaginal bacteria in other animal species such as the horse. The aim of this work was
to quantify the vaginal lactic acid bacteria and lactobacilli of mares and to establish if selected equine vaginal lactic
acid bacteria, particularly Lactobacillus and Enterococcus spp. strains, could exhibit potential as probiotics. The vaginal lactic acid bacteria and lactobacilli of 26 mares were quantified
by plate counts. Five strains (three Lactobacillus spp. and two Enterococcus spp.) were characterised and adhesion to vaginal epithelial cells, antimicrobial activity and ability to form biofilms were
evaluated. Lactic acid bacteria were recovered from the 26 samples and lactobacilli counts were detected in 18 out of 26 mares
(69%). Probiotic properties tested in this study varied among the isolates and showed promising features for their use as
equine probiotics. 相似文献
16.
Succinic acid production from wheat using a biorefining strategy 总被引:2,自引:0,他引:2
The biosynthesis of succinic acid from wheat flour was investigated in a two-stage bio-process. In the first stage, wheat
flour was converted into a generic microbial feedstock either by fungal fermentation alone or by combining fungal fermentation
for enzyme and fungal bio-mass production with subsequent flour hydrolysis and fungal autolysis. In the second stage, the
generic feedstock was converted into succinic acid by bacterial fermentation by Actinobacillus succinogenes. Direct fermentation of the generic feedstock produced by fungal fermentation alone resulted in a lower succinic acid production,
probably due to the low glucose and nitrogen concentrations in the fungal broth filtrate. In the second feedstock production
strategy, flour hydrolysis conducted by mixing fungal broth filtrate with wheat flour generated a glucose-rich stream, while
the fungal bio-mass was subjected to autolysis for the production of a nutrient-rich stream. The possibility of replacing
a commercial semi-defined medium by these two streams was investigated sequentially. A. succinogenes fermentation using only the wheat-derived feedstock resulted in a succinic acid concentration of almost 16 g l–1 with an overall yield of 0.19 g succinic acid per g wheat flour. These results show that a wheat-based bio-refinery employing
coupled fungal fermentation and subsequent flour hydrolysis and fungal autolysis can lead to a bacterial feedstock for the
efficient production of succinic acid. 相似文献
17.
Amita Tuli R.P. Sethi P.K. Khanna S.S. Marwaha J.F. Kennedy 《Enzyme and microbial technology》1985,7(4):164-168
Two matrices have been assessed for their ability to immobilize Lactobacillus casei cells for lactic acid fermentation in whey permeate medium. Agar at 2% concentration was found to be a better gel than polyacrylamide in its effectiveness to entrap the bacterial cells to carry out batch fermentation up to three repeat runs. Of the various physiological parameters studied, temperature and pH were observed to have no significant influence on the fermentation ability of the immobilized organism. A temperature range of 40–50°C and a pH range of 4.5–6.0 rather than specific values, were found to be optimum when fermentation was carried out under stationary conditions. In batch fermentation ~90% conversion of the substrate (lactose) was achieved in 48 h using immobilized cell gel cubes of 4 × 2 × 2 mm size, containing 400 mg dry bacterial cells per flask and 4.5% w/v (initial) whey lactose content as substrate. However, further increase in substrate levels tested (>4.5% w/v) did not improve the process efficiency. Supplementation of Mg2+ (1 mM) and agricultural by-products (mustard oil cake, 6%) in the whey permeate medium further improved the acid production ability of the immobilized cells under study. 相似文献
18.
A new bacterial strain producing succinic acid was enriched from bovine rumen content. It is facultatively anaerobic, belongs
to the family Pasteurellaceae and has similarity to the genus Mannheimia. In batch cultivations with D-glucose or sucrose the strain produced up to 5.8 g succinic acid l−1 with a productivity and a yield of up to 1.5 g l−1 h−1 and 0.6 g g−1, respectively. With crude glycerol up to 8.4 g l−1, 0.9 g l−1 h−1 and 1.2 g g−1 were obtained.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Characterisation of the microbiota of rice sourdoughs and description of Lactobacillus spicheri sp. nov 总被引:5,自引:0,他引:5
The microbiota of two industrially processed rice sourdoughs was characterised by bacteriological culture in combination with PCR-denaturing gradient gel electrophoresis (DGGE) and 16S/28S rDNA sequence analysis. Rice sourdough I was continuously propagated for several years by back-slopping every week, whereas sourdough II was processed by using a commercial starter culture and back-slopping daily for three days. In rice sourdough II Candida krusei and Saccharomyces cerevisiae as well as Lactobacillus fermentum, Lactobacillus gallinarum, Lactobacillus kimchii, Lactobacillus plantarum, and Lactobacillus pontis dominated at the first day of fermentation. RAPD analysis of lactobacilli revealed identical profiles for each of the species except for L. fermentum and L. pontis indicating the presence of different strains. Fluctuations within the LAB community during fermentation were monitored by PCR-DGGE. L. pontis decreased in numbers over time and L. curvatus became dominant after 3 days of fermentation. Rice sourdough I contained S. cerevisiae, Lactobacillus paracasei (present with three different RAPD types), Lactobacillus paralimentarius, and a Lactobacillus strain which could not be allotted to any valid species. Phylogenetic analysis based on 16S rDNA sequences revealed Lactobacillus brevis as the closest relative (97.3% sequence similarity). Differences in some phenotypic characteristics and DNA-DNA relatedness indicated that the strain represents a new Lactobacillus species, for which the name Lactobacillus spicheri is proposed. 相似文献
20.
Continuous lactic acid fermentations were conducted using lignocellulosic hydrolyzates and corn steep liquor as inexpensive raw materials. Lactic acid concentrations decreased with increases in the dilution rate, whereas the residual substrate concentrations increased. However, lactic acid yields were maintained at more than 0.90 g g−1 over all cases experimented. The cell-recycle cultivation system exerted positive effects on fermentation efficiency, including volumetric productivity, which is attributable to the retention of cells in the bioreactor. The cell-recycle continuous fermentation of lignocellulosic hydrolyzates yielded a lactic acid productivity of 6.7 g l−1 h−1 for a dilution rate of 0.16 h−1 using 30 g l−1 of corn steep liquor and 1.5 g l−1 of yeast extract as nutrients. The productivity (6.7 g l−1 h−1) acquired by the cell-recycle continuous fermentation of lignocellulosic hydrolyzates was 1.6 times higher than the lactic acid productivity yielded in the continuous fermentation without cell-recycle system. 相似文献