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1.
Fats and fatty acids as growth factors for Lactobacillus delbrueckii   总被引:3,自引:0,他引:3  
The effects of various fats and fatty acids on the growth of Lactobacillus delbrueckii strains have been studied using modified MRS broth without Tween 80 as a basic growth medium. Among the six L. delbrueckii strains studied all except one strain required Tween 80 or Tween 20 as a fatty acid supplement for the growth. Tween 40 and Tween 60, which contain solely medium and long chain saturated fatty acids, inhibited the growth of all L. delbrueckii strains when present as a sole fat supplement in MRS broth. Free oleic acid but not free lauric acid could substitute Tween 80 or Tween 20 supplement suggesting that unsaturated fatty acids are essential growth factors for most L. delbrueckii strains. Among the natural food oils tested, the oils containing the lowest amounts of saturated long chain fatty acids promoted the growth of L. delbrueckii most effectively. Especially cellular C18:1 and C19 cyclopropane fatty acid contents of L. delbrueckii were strongly affected by exogenous fatty acid composition and by strain suggesting genetic diversity and polymorphism among the genes encoding and/or regulating cyclopropane synthase. In addition obviously most if not all L. delbrueckii strains lack particular synthase, desaturase and/or dehydrase activities required for de novo synthesis of long chain unsaturated fatty acids. These biochemical features could be used as informative chemotaxonomic characteristics for L. delbrueckii starter strain identification and selection.  相似文献   

2.
Microthrix parvicella, cultivated in a medium with Tween 80 and Casamino acids, utilized only the oleic acid moiety of Tween 80 as carbon and energy source. The cell yield from Tween 80 was about 0.32 g dry weight of cells per g of Tween 80 consumed. As only the oleic acid moiety of Tween 80 was utilized, the cell yield from oleic acid was 1.3 g dry weight of cells per g oleic acid consumed. The amount of carbon produced as CO2 was less than 30% of the oleic acid-carbon and this low value was in agreement with the high cell yield. In batch culture M. parvicella stored large amounts of lipid material during the early growth phase. The fatty acids of the lipid globules were similar to the fatty acids supplied as carbon source. The percentage composition of the biomass changed to give C/N percentage ratios of about 15 during the early growth phase due to the high concentration of internal lipids and the low concentration of protein. The growth rate in batch culture was about 0.016 h-1 but was affected by the concentration of Casamino acids in the medium.  相似文献   

3.
The viability of Streptococcus lactis and Lactobacillus sp. A-12 after freezing at -17°C for 48 h was better preserved when the cells were grown in medium supplemented with oleic acid or Tween 80 (polyoxyethylene sorbitan monooleate). A pronounced change in the cellular fatty acid composition was noted when the bacteria were grown in the presence of Tween 80. In S. lactis the ratio of unsaturated to saturated fatty acids increased from 1.18 to 2.55 and in Lactobacillus sp. A-12 it increased from 0.85 to 1.67 when Tween 80 was added to the growth medium. The antibiotic cerulenin markedly inhibited the growth of lactic acid bacteria in tomato juice (TJ) medium but had almost no effect on the growth of the bacteria in TJ medium containing Tween 80 (or oleic acid). The antibiotic inhibited markedly the incorporation of [1-14C]acetate but had no inhibitory effect on the incorporation of exogenous [1-14C]oleate (or [1-14C]palmitate) into the lipid fractions of lactic acid bacteria. Thus, the fatty acid composition of lactic acid bacteria, inhibited by the antibiotic cerulenin, can be modulated by exogenously added oleic acid (or Tween 80) without the concurrent endogenous fatty acid synthesis from acetate. The data obtained suggest that cerulenin inhibits neither cyclopropane fatty acid synthesis nor elongation of fatty acid acyl intermediates. The radioactivity of cells grown in the presence of [1-14C]oleate and cerulenin was associated mainly with cyclopropane Δ19:0, 20:0 + 20:1, and 21:0 acids. As a consequence, cerulenin caused a decrease in the ratio of unsaturated to saturated fatty acids in lactic acid bacteria as compared with cells grown in TJ medium plus Tween 80 but without cerulenin. Cerulenin caused a decrease in the viability of S. lactis and Lactobacillus sp. A-12 after freezing at -17°C for 48 h only when Tween 80 was present in the growth medium. We conclude that the sensitivity of lactic acid bacteria to damage from freezing can be correlated with specific alterations in the cellular fatty acids.  相似文献   

4.
Effect of various nonionic surfactants on growth of Escherichia coli   总被引:1,自引:0,他引:1  
Rose, Michael J., Jr. (Veterans Administration Hospital, Washington, D.C.), Stephen A. Aron, and Bernard W. Janicki. Effect of various nonionic surfactants on growth of Escherichia coli. J. Bacteriol. 91:1863-1868. 1966.-Escherichia coli cultivated in media containing 0.5, 1.0, 2.0, or 4.0% concentrations of surface-active polyoxyethylene derivatives of formaldehyde polymers of octyl phenol (Triton WR-1339; Macrocyclon) or of sorbitan mono-fatty acid esters (Tween 20, 40, 60, and 80) exhibited significantly retarded growth only at the highest concentration. To determine the mechanism of bacteriostasis, certain derivatives and compounds related to the surfactants were investigated. Experiments with compounds related to the Triton-type agents demonstrated that incorporation of monomeric substances (Triton X-205, X-305, Igepal CA-730, or Dowfax 9N20) into the medium at a concentration of 4.0% did not inhibit the growth of E. coli. It was concluded that the formaldehyde polymer was essential for growth inhibition by the polyoxyethylene derivatives of octyl phenol. The inhibitory activity of the Tween compounds, in contrast, appeared to result from the unesterified fatty acids which contaminate the commercial preparations. Polyol (60), the sorbitan polyoxyethylene derivative of Tween 60 and the basic structural unit of all the Tween-type compounds, and a Tween 80 preparation which was purified by extraction of the unesterified oleic acid, were not inhibitory. Moreover, the amount of free oleic acid present as a contaminant of Tween 80 was found to be sufficient to cause significant growth inhibition. These results and the observation that E. coli does not appear to hydrolyze the esterified fatty acid of Tween 80 led to the conclusion that growth inhibition obtained with various Tween compounds probaby is a function of their respective fatty acid contaminants.  相似文献   

5.
Fatty acid requirement of Treponema denticola and Treponema vincentii   总被引:1,自引:0,他引:1  
Treponema denticola and Treponema vincentii were cultured in a medium supplemented with either 0.2 or 0.4% (w/v) alpha globulin in place of serum. The active factor(s) in alpha globulin was stable at pH 7.0 to autoclaving and was nondialyzable. Extraction of lipids from alpha globulin showed that both protein and lipid, supplied by the alpha globulin, were required for maximal growth of these two oral treponemes. The lipid component was investigated by adding sodium salts of long-chain fatty acids to the basal medium supplemented with 0.4% delipified alpha globulin. The lipid component of alpha globulin was replaced by either oleic acid (cis-18:1(9)) or by elaidic acid (trans- 18:1 (9)0. No other saturated or unsaturated fatty acid tested could support good growth. Tween 80 (polysorbitan monooleate) was the only Tween compound able to support maximal growth of T. denticola. The cellular lipids of T. denticola, grown with oleate in broth supplemented with 0.4% delipified alpha globulin, were extracted and analyzed by gas chromatography. The principle fatty acids were myristic, pentadecanoic, and palmitic acids. Lesser amounts of oleic acid, eicosadienoic acid, and an unidentified fatty acid (retention time, 88 min) were also detected. Treponema denticola appears to be capable of limited synthesis of cellular fatty acids such as myristic, pentadecanoic, and palmitic acids from oleic acid.  相似文献   

6.
Tween 80, which caused increased biomass formation, also produced the highest increase in the uptake rate of all components of the medium. The fatty acid components of the respective Tweens,i.e. palmitic acid (Tween 40), stearic acid (Tween 60), and oleic acid (Tween 80), have no effect either on alkaloid production or on substrate uptake. The fatty acid composition was different in the cell membrane of the culture supplemented with Tween 60 and facilitated the transport of metabolites into the cells.  相似文献   

7.
Summary Ligninase production by Phanerochaete chrysosporium MZKIBK-B 186 was increased when the culture medium was supplemented with an emulsion of oleic acid. Addition of linseed oil enhanced fungal biomass synthesis. Under the growth conditions used in our tests, the fungus was capable of accumulating fatty acids from the culture medium into cell lipids. Addition of oleic acid, Tween 80, or 3-[(cholamidopropyl)-dimethylammonio]-1-propanesulphonate (CHAPS), which are known to increase ligninase production by fungi, resulted in oleic acid enrichment of whole cell and polar lipids. Offprint requests to: D. Le相似文献   

8.
Smegmatocin, a protein produced by Mycobacterium smegmatis ATCC 14468, was found to have an esterase activity, hydrolyzing Tween 80, polyoxyethylene sorbitan monooleate, added to the assay medium for various "bacteriocins" from mycobacteria. Because M. diernhoferi ATCC 19340 (indicator strain for smegmatocin) is highly susceptible to oleic acid and smegmatocin requires Tween 80 for manifestation of its anti-M. diernhoferi activity, it is likely that smegmatocin-mediated antimicrobial action is caused by oleic acid generated by hydrolysis of Tween 80 by the inherent esterase action of smegmatocin. Other mycobacteriocins from rapidly growing mycobacteria also have inherent esterase activity against Tween 80 and require Tween 80 for expression of antimycobacterial action. Smegmatocin was found to hydrolyze various polyoxyethylene (sorbitan) fatty acyl esters but not sorbitan monooleate and glyceryl esters.  相似文献   

9.
Uziel A  Kenneth RG 《Mycopathologia》1998,144(3):153-163
Primary conidia of the entomopathogens Erynia (subgenus Neopandora) delphacis (1 isolate) and Erynia ( Neopandora) neoaphidis (3 isolates) were stimulated to form germ-tubes with Tween 20 and with free, long-chain fatty acids, each incorporated into Entomophthora complete medium (ECM). When combined with other basal media (three tested), these compounds did not stimulate germ-tube formation. Triacylglycerols and vegetable oils, added to the same media, allowed almost complete resporulation in the fungi. In both species, Tween 20 (0.1%) encouraged greater germ-tube production (41–69%) than the fatty acids (0.1%) (≤36%). For E. delphacis, Tween 20 and the fatty acids differed significantly, but for E. neoaphidis the differences were almost always insignificant. Myristic and oleic acids stimulated germ-tube formation in both species. Palmitic acid allowed almost complete resporulation of the fungi, except for one isolate of E. neoaphidis that formed germ-tubes. Linoleic acid, tested only for E. delphacis, was fungistatic to most conidia. Higher concentrations of the fatty acids (≤1%) did not increase germ-tube formation, except 1% oleic acid which affected E. delphacis alone (>80% germination and germ-tubes). Linoleic acid, and sometimes also myristic and oleic, were fungistatic and/or toxic, depending on their concentration and on medium composition. Addition of fatty acids to ECM usually extended the lag period, and altered the morphology of the conidia and germ-tubes. These phenomena were not observed with Tween 20. Colonies were formed by E. delphacis alone, stimulated by ECM supplemented with Tween 20 or fatty acids. The results are discussed with respect to biological and physiological aspects of germination, and with respect to the mode of action of the fatty acids and the surfactant. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

10.
The aim of this study was to investigate the effect of altering the fatty acid profile of the lipid membrane on storage survival of freeze‐dried probiotic, Lactobacillus acidophilus La‐5, as well as study the membrane integrity and lipid oxidation. The fatty acid composition of the lipid membrane of L. acidophilus La‐5 was significantly different upon growth in MRS (containing Tween 80, an oleic acid source), or in MRS with Tween 20 (containing C12:0 and C14:0), linoleic, or linolenic acid supplemented. Bacteria grown in MRS showed the highest storage survival rates. No indications of loss of membrane integrity could be found, and membrane integrity could therefore not be connected with loss of viability. Survival of bacteria grown with linoleic or linolenic acid was more negatively affected by the presence of oxygen, than bacteria grown in MRS or with Tween 20 supplemented. A small, but significant, loss of linolenic acid during storage could be identified, and an increase of volatile secondary oxidation products during storage was found for bacteria grown in MRS, or with linoleic, or linolenic acid supplemented, but not for bacteria grown with Tween 20. Overall, the results indicate that lipid oxidation and loss of membrane integrity are not the only or most important detrimental reactions which can occur during storage. By altering the fatty acid composition, it was also found that properties of oleic acid gave rise to more robust bacteria than more saturated or unsaturated fatty acids did. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:799–807, 2015  相似文献   

11.
The lipid composition of a Saccharomyces cerevisiae mutant (GL 1–38) lacking δ-aminolevulinic acid synthase (EC 2.3.1.37) was investigated. This mutant is unable to synthesize heme compounds and, as a consequence, cannot make unsaturated fatty acids or ergosterol. The mutant cells were grown (i) in medium supplemented with δ-aminolevulinic acid or (ii) in medium supplemented with Tween 80 (as a source of oleate) and ergosterol. After growth in the presence of δ-aminolevulinic acid, the fatty acid composition of total lipids and mitochondrial lipids was the same as that of the corresponding wild-type strain. After growth in the presence of Tween 80 and ergosterol, the mutant cells contained increased levels of oleate and greatly decreased levels of palmitoleate. The ratio of unsaturated to saturated fatty acids in these cells was still close to that of the wild type but much lower than that of the medium. The sphingolipids accounted for 5.2% of the lipid phosphate in the wild type and, after growth in Tween 80 and ergosterol, for 12.7% in the mutant. Changes in other phospholipids were too small to be considered significant.  相似文献   

12.
Tween 80 (0.1%, v/v) added to Thermomonospora curvata growing in minimal medium caused a transient lowering of the dry cell mass, decreased the optimal growth temperature of the thermophile from 62 to 54°C, and increased extracellular esterase activity. Cells grown in the presence of Tween 80 had decreased concentrations of branched chain fatty acids and increased concentrations of oleic acid. The detergent removed surface protuberances from mycelia and increased the liberation of enzymes active against crystalline cellulose, but did not stimulate liberation of enzymes active against carboxymethylcellulose, starch or pectin.  相似文献   

13.
The physiology of Saccharomyces cerevisiae CBS 8066 was studied in anaerobic glucose-limited chemostat cultures in a mineral medium supplemented with ergosterol and Tween 80. The organism had a mu max of 0.31 h-1 and a Ks for glucose of 0.55 mM. At a dilution rate of 0.10 h-1, a maximal yield of 0.10 g biomass (g glucose)-1 was observed. The yield steadily declined with increasing dilution rates, so a maintenance coefficient for anaerobic growth could not be estimated At a dilution rate of 0.10 h-1, the yield of the S. cerevisiae strain H1022 was considerably higher than for CBS 8066, despite a similar cell composition. The major difference between the two yeast strains was that S. cerevisiae H1022 did not produce acetate, suggesting that the observed difference in cell yield may be ascribed to an uncoupling effect of acetic acid. The absence of acetate formation in H1022 correlated with a relatively high level of acetyl-CoA synthetase. The uncoupling effect of weak acids on anaerobic growth was confirmed in experiments in which a weak acid (acetate or propionate) was added to the medium feed. This resulted in a reduction in yield and an increase in specific ethanol production. Both yeasts required approximately 35 mg oleic acid (g biomass)-1 for optimal growth. Lower or higher concentrations of this fatty acid, supplied as Tween 80, resulted in uncoupling of dissimilatory and assimilatory processes.  相似文献   

14.
A different capability to assimilate oleic acid from the culture medium has been demonstrated among malolactic Oenococcus oeni strains. Strains possessing higher percentages of oleic acid and its methylated derivative, dihydrosterculic acid, in their fatty acid profile showed higher cell viability and carried out a complete malolactic fermentation after their transfer into a wine lacking oleic acid. Wine supplementation with Tween 80 (polyoxyethylene-sorbitan-mono-oleate) enhanced cell survival of strains with lower capability to assimilate oleic acid and caused cell growth of strains with higher assimilative capacity, suggesting that oleic acid may act in wine as a survival factor for the former strains and as a growth factor for the latter strains. Practical consequences of these findings are also discussed. Received: 24 March 2001 / Accepted: 25 April 2001  相似文献   

15.
Streptococcus salivarius (ATCC 25975) produced very low or nondetectable amounts of the extracellular enzyme glucosyltransferase (GTase) when grown in a chemically defined medium. The addition of Tween 80 to this medium resulted in the production of markedly enhanced levels of the enzyme. Oleic acid, the methyl ester of oleic acid, and sucrose each could not substitute for Tween 80 in this regard. The surfactant had no direct activating effect on performed enzyme activity. Tween 80 also stimulated the production of GTase by concentrated cells suspended in defined medium during a time when no measurable growth occurred. Under these conditions, the stimulatory effect of Tween 80 was blocked by chloramphenicol. It was further found that the surfactant dramatically stimulated the differential rate of GTase synthesis. These and other data strongly suggest that Tween 80 stimulates the production of extracellular GTase by acting either directly or indirectly at the level of enzyme synthesis.  相似文献   

16.
It is well known that biotin has a marked effect on l-glutamic acid fermentation.

The authors have intended to find strains which are independent of the amounts of biotin in the culture medium. As a result, oleic acid-requiring mutants were obtained from a strain of Brevibacterium thiogenitalis which is an auxotroph for biotin. The growth of the mutant was remarkably stimulated by Tween 20, 40, 60, Ca ions and a small amount of corn steep liquor. And also, the mutant was found to have lost its requirement for biotin and showed growth response only to oleic acid or unsaturated fatty acids.

The effect of biotin, oleic acid and other unsaturated fatty acids on the production of l-glutamic acid was investigated by using an oleic acid-requiring mutant of Brevibacterium thiogenitalis No. 653. The results described in the present paper showed that the oleic acid-requiring mutant D-248 produced a large amount of l-glutamic acid in the excess biotin-contaming media, and that oleic acid seemed to be completely replaced by other unsaturated fatty acids such as palmitoleic acid and linoleic acid.  相似文献   

17.
Effect of different carbon sources on lipase production by Candida rugosa   总被引:1,自引:0,他引:1  
Different carbon sources affecting growth and lipase production in Candida rugosa were studied by using batch cultures on defined medium. Carbohydrates and acids non-related to fats did not induce lipase production. The highest yields of enzyme were obtained with lipids or fatty acids as carbon sources. Tween 80 stimulated lipase biosynthesis and secretion outside the cell. Combinations of two types of substrates, carbohydrates and fatty acids, did not improve lipase production, and in some cases, their consumption was produced in a sequential pattern. Glucose presented a repressing effect on lipase production. Moreover, glucose was found to be effective in stimulating lipase secretion by cells with a high level of cell-bound lipase activity because of their previous growth in oleic acid.  相似文献   

18.
Y Umesaki  Y Kawai    M Mutai 《Applied microbiology》1977,34(2):115-119
Glucan production from sucrose by Streptococcus mutans OMZ 176 was stimulated approximately threefold in the presence of 0.1% Tween 80. When OMZ 176 was grown in a medium containing glucose, the glucosyltransferase level in the medium was also increased about fivefold in the presence of 0.1% Tween 80. The glucosyltransferase level increased in proportion to the logarithm of the concentration of Tween 80 in the glucose medium. Tween 80 affected neither bacterial growth nor the activity of glucosyltransferase. The appearance of glucosyltransferase in the glucose medium was inhibited immediately by chloramphenicol and actinomycin D and, after a lag, by rifampin as well. It was observed that the fatty acid composition of the cells grown with Tween 80 was altered. These results suggest that Tween 80 stimulates glucosyltransferase synthesis either directly, or indirectly by promoting glucosyltransferase secretion.  相似文献   

19.
When Streptococcus salivarius was grown in batch culture in the presence of various Tween detergents, the fatty acid moiety of the detergent was incorporated into the lipids of its membrane. Tween 80 (containing primarily oleic acid) markedly stimulated the production of extracellular glucosyltransferase and also increased the degree of unsaturation of the membrane lipid fatty acids. The possibility that an increase in membrane unsaturated fatty acids promoted extracellular glucosyltransferase production was examined by growing cells at different temperatures in the presence or absence of Tween 80. The membrane lipids of cells grown at 30 degrees C, 37 degrees C and 40 degrees C without Tween 80 exhibited unsaturated/saturated fatty acid ratios of 2.06, 1.01 and 0.87 respectively. A significant increase in the production of extracellular glucosyltransferase was observed at 30 degrees C compared to cells grown at 40 degrees C. However, cells produced much more exoenzyme at all temperatures when grown with Tween 80. The results indicated that an increase in the unsaturated fatty acid content of the membrane lipids was not by itself sufficient to account for the stimulation of extracellular glucosyltransferase production by Tween 80, but that the surfactant also had to be present.  相似文献   

20.
Addition of Tween 80 to biotin assay medium containing acid-hydrolyzed casein as the amino acid source caused marked growth of Lactobacillus plantarum ATCC 8014 in the absence of added biotin. This growth-promoting activity could be eliminated by treating the "vitamin-free" Casamino Acids (Difco) with activated charcoal (Darco G-60) at pH 3.5 for 30 to 60 min. Incorporation of Tween 80 and charcoal-purified Casamino Acids (PCA) into the assay medium (0.8 g and 27 g, respectively, per liter of single strength medium) in place of unpurified Casamino Acids resulted in a medium in which L. plantarum responded to 30 to 50 times less biotin over an extended linear response range (1.3 logs versus 1.0 log) than was required for similar growth in the standard medium. Endogenous growth in the modified medium was absent if the inoculum used was of low density, if it was prepared from biotin-deficient cells, and if the reagents used were free from contaminating traces of biotin. Assays of biological materials for biotin content using the standard medium and the Tween 80-PCA-modified medium resulted in nearly identical values for all samples tested.  相似文献   

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