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1.
The fatty acid components of awamori during aging were as follows. The total amount of volatile acids calculated as acetic acid ranged from 20 to 140 mg/l, the main acid was acetic acid, and the proportion of acetic acid to total acids ranged from 35 to 80 per cent. The main acids other than acetic acid were propionic acid and i-butyic acid. Differences were observed in fatty acid constituents between awamori and other alcoholic beverages.Certain components tended to increase during maturation in kame (porous earth-enware pots): acetic acid, i-butyric acid, i-valeric acid, valeric acid, capric acid, lauric acid, myristic acid and total fatty acids. Others, however, showed no distinct changes: propionic acid, butyric acid, caproic acid, caprylic acid, palmitic acid, stearic acid, oleic acid and linoleic acid.During maturation in non-porous containers (stainless-steel or glass-linked tanks), on the other hand, caprylic acid, capric acid, lauric acid and myristic acid components tended to increase, while no distinct changes however were shown by acetic acid, propionic acid, i-butyric, butyric acid, i-valeric acid, valeric acid, caproic acid, palmitic acid, stearic acid, oleic acid, linoleic acid and total fatty acids.  相似文献   

2.
AIMS: To determine susceptibility of Clostridium perfringens strains CCM 4435(T) and CNCTC 5459 to C(2)-C(18) fatty acids, and evaluate influence of pH in cultures grown on glucose. Straw particles were added to cultures to simulate the presence of solid phase of the digestive tract milieu. METHODS AND RESULTS: Antimicrobial activity of fatty acids was expressed as a concentration at which only 50% of the initial glucose was utilized. Lauric acid showed the highest antimicrobial activity, followed by myristic, capric, oleic and caprylic acid. Only strain CNCTC 5459 was susceptible to linoleic acid. Neither caproic acid and acids with a shorter carbon chain nor palmitic and stearic acid influenced substrate utilization. The antimicrobial activity of myristic, oleic and linoleic acid decreased when clostridia were grown in the presence of straw particles. In cultures of both strains treated with capric and lauric acid at pH 5.0-5.3, the number of viable cells was <10(2) ml(-1). Only lauric acid reduced number of viable cells of both strains below 10(2) ml(-1) at pH > 6. Transmission electron microscopy revealed separation of inner and outer membranes and cytoplasma disorganization in cells treated with lauric acid. CONCLUSIONS: Lauric acid had the highest activity towards C. perfringens among fatty acid tested. Its activity was not influenced by the presence of solid particles and did not cease at pH > 6. SIGNIFICANCE AND IMPACT OF THE STUDY: Lauric acid might be a means for control of clostridial infections in farm animals.  相似文献   

3.
Few studies have addressed the presence and bioactivity of endophytic fungi living in plantlets growing under in vitro conditions. After unfruitful attempts to grow axenic shoot cultures of the medicinal plant Smallanthus sonchifolius (yacon) were made, healthy shoots grew on half strength Murashigue and Skoog media supplemented with 2.2 μM benzylaminopurine without sucrose. We isolated a fungus UM109 from these autotrophic tissue cultures and it was identified as Coniochaeta ligniaria using molecular, physiological and morphological methods. Dichloromethane extracts from C. ligniaria and its host S. sonchifolius exhibited antifungal activity against phytopathogenic fungi Colletotrichum acutatum, C. fragariae and C. gloeosporioides. Both extracts of C. ligniaria and S. sonchifolius were subjected to antifungal bioassay-directed fractionation using NMR spectroscopy and GC-FID analysis. Twelve antifungal fatty acids were identified and 8 out of the total were produced by the fungus and the plant including caproic, caprylic, myristic, palmitic, heptadecanoic, stearic, oleic and linoleic acids. Additionally, caproic, caprylic and palmitic acids were produced at high concentrations by the endophytic fungus and its host. The detection of these antifungal fatty acids produced by both C. ligniaria and S. sonchifolius suggests that these bioactive compounds may be partially responsible for the high resistance of S. sonchifolius to phytopathogenic fungal attacks. This finding also indicates the existence of an interesting chemical symbiosis between an endophytic fungus and its host. Furthermore, the isolation of C. ligniaria from tissue culture of S. sonchifolius demonstrates that plantlets growing in vitro as autotrophic cultures can shelter specific endophytic fungal communities. The use of autotrophic tissue cultures may become an important tool for studies on the taxonomy, ecology, evolution and biotechnological application of endophytes.  相似文献   

4.
Susceptibility of the rabbit enteropathogenic strain Escherichia coli C6 (O128 serogroup) to C6-C14 fatty acids, oleic, citric, lactic and fumaric acid at 5 mg/mL was determined by the plating technique in the near-neutral pH region (pH approximately 6.5), and in a weakly acid and acid environment (pH 5.4 +/- 0.1 and 2.2-2.5, respectively). In the near-neutral pH region caproic and caprylic acid reduced the concentration of viable cells by 3 and 6 orders, respectively. At lower pH the bactericidal effect of caproic acid remained similar, but caprylic acid decreased the concentration of viable cells to < 100/mL. The bactericidal activity of capric acid was low at pH 6.5 but increased at pH 5.3. High environmental acidity was intrinsically bactericidal and at very low pH the effects of fatty acids were thus less pronounced. Citric acid reduced the counts of viable cells to 1/10. Antimicrobial activity of other acids examined was marginal or absent. Medium-chain fatty acids, caprylic and, to a lesser extent, also caproic and capric acid were better antimicrobials than other organic acids examined; the antimicrobial activity of fatty acids toward the C6 strain was pH-dependent. Beneficial effects of citric, lactic and fumaric acid reported by animal nutritionists are thus probably related to factors other than their direct antimicrobial action.  相似文献   

5.
The antifungal properties of extracellular compounds produced by the epiphytic fungus Sporothrix flocculosa were bioassayed against phytopathogenie fungi on the basis of inhibition of spore germination, and mycelial growth and induction of cellular leakage. Following incubation in stationary culture, S. flocculosa released antifungal metabolites into the culture medium which were extractable with méthylene chloride. When separated by thin layer chromatography, extracted metabolites yielded a compound(s) at Rf0.65 which inhibited development of Cladosporium cucumerinum and several other phytopathogenic fungi. Treatment of Botrytis cinerea and Fusarium oxysporum f.sp. radicis‐lycopersici (FORL) with the same compound(s) greatly reduced spore germination and biomass growth of both fungi. Additionally, both B. cinerea and FORL leaked electrolytes and proteins when grown in presence of the metabolites. Observations under electron microscopy revealed that FORL reacted to the presence of S. flocculosa metabolites by retraction of the plasmalemma and rapid disintegration of the cytoplasm. These reactions were similar to the ones induced by conidia of S. flocculosa when applied on powdery mildew fungi. These results provide strong evidence of the production of antifungal compounds in vivo and of their role in the antagonistic properties of S. flocculosa.  相似文献   

6.
The hygroscopic secretion produced by the secretory setae of terrestrial larvae of the biting midge Forcipomyia nigra (Winnertz) was analysed using gas chromatography coupled with mass spectrometry (GC-MS). The viscous secretion is stored at the top of each seta and absorbs water from moist air. GC-MS analyses (four independent tests) showed that the secretion contained 12 free fatty acids, the most abundant of which were oleic (18:1), palmitic (16:0), palmitoleic (16:1) and linoleic (18:2). Other acids identified were valeric (5:0), enanthic (7:0), caprylic (8:0), pelargonic (9:0), capric (10:0), lauric (12:0), myristic (14:0) and stearic (18:0). Two other compounds, glycerol and pyroglutamic acid, were also found. The antibacterial activity of the fatty acids and pyroglutamic acid was tested using the agar disc diffusion method and targeted Gram positive (Bacillus cereus, Bacillus subtilis, Enterococcus faecalis) and Gram negative bacterial strains (Citrobacter freundii, Pseudomonas aeruginosa, Pseudomonas fluorescens). The antifungal activity was tested by determining minimal inhibitory concentration (MIC) of examined compounds. Fatty acids were tested against enthomopathogenic fungi (Paecilomyces lilacinus, Paecilomyces fumosoroseus, Lecanicillium lecanii, Metarhizium anisopliae, Beauveria bassiana (Tve-N39), Beauveria bassiana (Dv-1/07)). The most effective acids against bacterial and fungal growth were C(9:0), C(10:0) and C(16:1), whereas C(14:0), C(16:0,) C(18:0) and C(18:1) demonstrated rather poor antifungal activity and did not inhibit the growth of bacteria. The antimicrobial assay investigated mixtures of fatty and pyroglutamic acids (corresponding to the results of each GC-MS test): they were found to be active against almost all the bacteria except P. fluorescens and also demonstrated certain fungistatic activity against enthomopathogenic fungi. The hygroscopic secretion facilitates cuticular respiration and plays an important role in the antimicrobial protection of F. nigra larvae living in moist terrestrial habitats.  相似文献   

7.
Data are presented that indicate the dynamic changes of nutrients in milk from three free ranging African elephant (Loxodonta africana africana) cows during lactation. At the respective collection times of 12, 14 and 18 months of lactation the nutrient content was 47.3, 52.0 and 68.6 g protein; 60.7, 87.4 and 170.8 g fat; 1.6, 2.1 0.5 g lactose and 20.9, 21.5 and 8.6 g oligosaccharides per kg milk. The protein fraction respectively consisted of 18.0, 31.7 and 45.9 g caseins/kg milk and of 29.3, 20.3 and 22.7 g whey proteins/kg milk. Electrophoresis and identification of protein bands showed that polymorphs of one whey protein may be present in elephant's milk similar to polymorphs of alpha-lactalbumin found in cow's milk. From the middle of the lactation time lactose was replaced by oligosaccharides as major carbohydrate, and the major compound of these was identified as isoglobotriose by 1H NMR spectroscopy. The lipid fraction contains a high content, of capric and lauric acids, approximately 70% of the total fatty acids, and low content of myristic, palmitic and oleic acids. During these lactation times the content of short chain fatty acids, capric and caprylic acids increased, while fatty acids lauric acid and longer decreased.  相似文献   

8.
Pseudomonas fluorescens strain G308 isolated from barley leaves produces a novel antibiotic substance that was purified by preparative TLC and HPLC and identified as N-mercapto-4-formylcarbostyril (Cbs) by LC/DAD, IR, LC-ES(+)/MS, LC-ES(-)/MS, GC-EI/MS, LC-HRES(+)/MS, mass isotope ratios analysis, 1H NMR and 13C NMR analysis. The purified new antibiotic compound is effective against many phytopathogenic fungi in vitro. The compound inhibited at 25 ppm spore germination and germ tube growth of the following fungi; Fusarium oxysporum f. sp. lycopersici, Fusarium culmorum, Cladosporium cucumerinum and Colletotrichum lagenarium. At concentrations up to 125 ppm, the compound did not interfere with release of zoospores from sporangia and germination of encysted zoospores of Phytophthora infestans.  相似文献   

9.
The effect of the fatty acids linolenic acid, linoleic acid, erucic acid and oleic acid on the growth of the plant pathogenic fungi Rhizoctonia solani, Pythium ultimum, Pyrenophora avenae and Crinipellis perniciosa were examined in in vitro studies. Linolenic and linoleic acids exhibited activity against all of the fungi. However, whereas linolenic acid reduced mycelial growth of R. solani and C. perniciosa at 100 microM, the concentration had to be increased to 1000 microM before any effect on mycelial growth of P. ultimum and P. avenae was observed. Linoleic acid only reduced mycelial growth of R. solani, P. ultimum and P. avenae at 1000 microM, but led to a significant reduction in growth of C. perniciosa at 100 microM. In contrast, oleic acid had no significant effect on growth of R. solani or P. avenae, but gave significant reductions in mycelial growth of P. ultimum at 100 microM and reduced growth of C. perniciosa significantly at 1000 microM. All of the fatty acids reduced biomass production by all of the fungi significantly in liquid culture when added to the media at 100 microM. Erucic acid had no effect on fungal growth at any concentration examined. The antifungal activities exhibited by linolenic, linoleic and oleic acids may be useful in the search for alternative approaches to controlling important plant pathogens, such as those examined in this study.  相似文献   

10.
Fatty acid composition of seed lipids for 20 of the 26 genera in the Lythraceae and seed oil and protein content for nine genera are reported. The percent oil ranges from 2.7 to 34% of total weight and protein from 11.3 to 24.9%. Linoleic acid is the dominant fatty acid in seed lipids of all genera surveyed. Variations in pattern emphasize palmitic or oleic acid or both as second most abundant lipid component. There are three exceptions: in Diplusodon capric acid ranks second in abundance; in Adenaria lauric acid and oleic acid occur in approximately equal amounts as second most abundant fatty acid; in Decodon an unusual trienoic acid, previously reported only from the Compositae, is the main secondary component. Fatty acid composition of seeds in the genera is compared to that of the previously studied lythraceous genus Cuphea. Among all the genera, only Cuphea seed produces large quantities of lauric, capric, or caprylic acids, as well as a diversity of fatty acid patterns. No relationship between oil content or seed weight and habit is apparent in any genus studied, nor are differences in seed morphology reflected in composition of the seed lipids. The fatty acid patterns are judged evolutionarily conservative, with the strong exception of Cuphea, which remains unique in the Lythraceae and among all angiosperms for the diversity of patterns displayed.  相似文献   

11.
Lord JC  Howard RW 《Mycopathologia》2004,158(2):211-217
Maximum challenge exposure of Liposcelis bostrychophila to Beauveria bassiana, Paecilomyces fumosoroseus, Aspergillus parasiticus or Metarhizium anisopliae resulted in no more than 16% mortality. We investigated several of L. bostrychophila's cuticular lipids for possible contributions to its tolerance for entomopathogenic fungi. Saturated C14 and C16 fatty acids did not reduce the germination rates of B. bassiana or M. anisopliae conidia. Saturated C6 to C12 fatty acids that have not been identified in L. bostrychophila cuticular extracts significantly reduced germination, but the reduction was mitigated by the presence of stearamide. Cis-6-hexadecenal did not affect germination rates. Mycelial growth of either fungal species did not occur in the presence of caprylic acid, was reduced by the presence of lauric acid, and was not significantly affected by palmitic acid. Liposcelis bostrychophila is the only insect for which fatty acid amides have been identified as cuticular components. Stearamide, its major fatty amide, did not reduce germination of B. bassiana or M. anisopliae conidia or growth of their mycelia. Adhesion of conidia to stearamide preparations did not differ significantly from adhesion to the cuticle of L. bostrychophila. Pretreatment of a beetle known to be fungus-susceptible, larval Oryzaephilus surinamensis, with stearamide significantly decreased adhesion of B. bassiana or M. anisopliae conidia to their cuticles. This evidence indicates that cuticular fatty amides may contribute to L. bostrychophila's tolerance for entomopathogenic fungi by decreasing hydrophobicity and static charge, thereby reducing conidial adhesion.  相似文献   

12.
Structural models are proposed for amylose-fatty acid complexes depending on the respective chain lengths of their constituents. The three studied fatty acids induce the Vh amylose crystalline type. However, in contrast to lauric and palmitic acids, caprylic acid is not present in crystals. On the basis of the relative amounts of amylose and fatty acid determined in complexes and previous results of molecular modelling, inclusion of lauric and palmitic acids inside the amylose helices is proposed; the acyl chains are included in crystalline areas and the car☐ylic groups in amorphous areas. The absence of caprylic acid in crystals could be due to the solubility of this compound in the crystallization medium.  相似文献   

13.
The antimicrobial activity of C2-C18 fatty acids was determined in vitro in cultures of two strains of Escherichia coli grown on glucose. Antimicrobial activity was expressed as IC50 (a concentration at which only 50% of the initial glucose in the cultures was utilized). Utilization of glucose was inhibited by caprylic acid (IC50 0.30-0.85 g/L) and capric acid (IC50 1.25-2.03 g/L). Neither short-chain fatty acids (C2-C6) nor fatty acids with longer chain (C12-C18) influenced substrate utilization. Caproic acid, however, decreased cell yield in cultures of E. coli in a dose-dependent manner. No inhibition of glucose utilization was produced with unsaturated fatty acids, oleic and linoleic. Calcium ions added in excess reversed the antimicrobial effect of capric acid, but not that of caprylic acid. Antimicrobial activity of caprylic and capric acid decreased when the bacteria were grown in the presence of straw particles, or repeatedly subcultured in a medium containing these compounds at low concentrations. Counts of viable bacteria determined by plating decreased after incubation with caprylic and capric acid (30 min; 1 g/L) at pH 5.2 from > 10(9) to approximately 10(2)/mL. A reduction of a mere 0.94-1.96 log10 CFU was observed at pH 6.5-6.6. It can be concluded that caprylic acid, and to a lesser extent also capric acid, has a significant antimicrobial activity toward E. coli. Effects of other fatty acids were not significant or absent.  相似文献   

14.
In liver mitochondria fatty acids act as protonophoric uncouplers mainly with participation of internal membrane protein carriers — ADP/ATP and aspartate/glutamate antiporters. In this study the values of recoupling effects of carboxyatractylate and glutamate (or aspartate) were used to assess the degree of participation of ADP/ATP and aspartate/glutamate antiporters in uncoupling activity of fatty acids. These values were determined from the ability of these recoupling agents to suppress the respiration stimulated by fatty acids and to raise the membrane potential reduced by fatty acids. Increase in palmitic and lauric acid concentration was shown to increase the degree of participation of ADP/ATP antiporter and to decrease the degree of participation of aspartate/glutamate antiporter in uncoupling to the same extent. These data suggest that fatty acids are not only inducers of uncoupling of oxidative phosphorylation, but that they also act the regulators of this process. The linear dependence of carboxyatractylate and glutamate recoupling effects ratio on palmitic and lauric acids concentration was established. Comparison of the effects of fatty acids (palmitic, myristic, lauric, capric, and caprylic having 16, 14, 12, 10, and 8 carbon atoms, respectively) has shown that, as the hydrophobicity of fatty acids decreases, the effectiveness decreases to a greater degree than the respective values of their specific uncoupling activity. The action of fatty acids as regulators of uncoupling is supposed to consist of activation of transport of their anions from the internal to the external monolayer of the internal membrane with participation of ADP/ATP antiporter and, at the same time, in inhibition of this process with the participation of aspartate/glutamate antiporter.  相似文献   

15.
The activity of free saturated fatty acids (caprylic, capric, lauric, myristic, palmitic and stearic) as inducers and regulators of uncoupling of oxidative phosphorylation with participation of ADP/ATP antiporter, aspartate/glutamate antiporter and cyclosporin A-sensitive structure was investigated in experiments on rat liver mitochondria. It is established that at equal uncoupling activity of fatty acids the regulatory effect is minimal for caprylic acid and raised with increasing the hydrophobicity of fatty acids reaching the maximum value for stearic acid. There exists the linear dependence of the regulatory effect value of fatty acids on fatty acids content in the hydrophobic region of the inner membrane. The model that describes the interaction of fatty acids with the hydrophobic region of the mitochondrial inner membrane preserving functional activity of organelles is developed. It is established that if molecules of various fatty acids being in the hydrophobic region of the membrane are equally effective as uncoupling regulators, their specific uncoupling activity is different. Caprylic acid, a short-chain fatty acid, possesses the highest uncoupling activity. As the acyl chain length increases, the specific uncoupling activity of fatty acids reduces exponentially. Under these conditions components of the uncoupling activity sensitive to glutamate and carboxyatractylate and glutamate and insensitive to these reagents (but sensitive to cyclosporin A) change approximately equally.  相似文献   

16.
Summary Data are presented on the antagonistic effects of the fungi isolated from sclerotia ofSclerotium cepivorum and from nonrhizosphere soil taken from around the roots of infected onions upon mycelial growth and sclerotial germination ofS. cepivorum. Most of the isolated fungi especiallyPenicillium species were antagonistic to mycelial growth. Sclerotial germination was slightly inhibited by diffusates of these fungal isolates. Testing the antifungal effect of someAllium extracts against the fungal isolates by the inhibition zone method showed that garlic extract has the greatest antifungal effects and onion extract is the least potent. However, spore germination tests indicated that onion extract completely inhibits the spore germination of all test fungi. The role of host-plant extracts in stimulating sclerotial germination is discussed.  相似文献   

17.
The effect of four saturated long-chain fatty acids (caprylic, capric, lauric, and myristic) and one unsaturated long-chain fatty acid (oleic) on the microbial formation of methane from acetate was investigated in batch anaerobic toxicity assays. The tests were carried out with granular sludge from an upflow anaerobic sludge bed reactor. In this sludge, Methanothrix spp. are the predominant acetoclastic methanogens. Lauric acid appeared to be the most versatile inhibitor: inhibition started at 1.6 mM, and at 4.3 mM the maximum specific acetoclastic methanogenic activity had been reduced to 50%. Caprylic acid appeared to be only slightly inhibitory. Oleic acid was almost as inhibitory as lauric acid. Although adsorption of the inhibitor on the cell wall might play an important role in the mechanism of inhibition, the inhibition was found to be correlated with concentration rather than with the amount per unit of biomass. In practical situations, as in anaerobic waste treatment processes, synergism can be expected to enhance the inhibition of methanogenesis. In the present research a background concentration of lauric acid below its MIC strongly enhanced the toxicity of capric acid and (to an even greater extent) myristic acid.  相似文献   

18.
For the first time, the solid–liquid phase diagrams of five binary mixtures of saturated fatty acids are here presented. These mixtures are formed of caprylic acid (C8:0) + capric acid (C10:0), capric acid (C10:0) + lauric acid (C12:0), lauric acid (C12:0) + myristic acid (C14:0), myristic acid (C14:0) + palmitic acid (C16:0) and palmitic acid (C16:0) + stearic acid (C18:0). The information used in these phase diagrams was obtained by differential scanning calorimetry (DSC), X-ray diffraction (XRD), FT–Raman spectrometry and polarized light microscopy, aiming at a complete understanding of the phase diagrams of the fatty acid mixtures. All of the phase diagrams reported here presented the same global behavior and it was shown that this was far more complex than previously imagined. They presented not only peritectic and eutectic reactions, but also metatectic reactions, due to solid–solid phase transitions common in fatty acids and regions of solid solution not previously reported. This work contributes to the elucidation of the phase behavior of these important biochemical molecules, with implications in various industrial applications.  相似文献   

19.
五种新疆植物的抗真菌活性   总被引:7,自引:4,他引:7  
对采自新疆的黄花蒿(Artemisia annua)、北艾(Artemisia vulgaris)、梭梭(Halaxylon ammodendron)、盐爪爪(Kalidium foliatum)和多枝柽柳(Tamarix ramosissima)抗植物病原真菌的活性进行了研究,植物病原真菌包括番茄灰霉病菌(Botrytis cinerea)、棉花枯萎病菌(Fusarium axysporum f.sp.vasinfectum)、稻瘟病菌(Magnaporthe grisea)、烟草黑胫病菌(Phytophthora parasitica var.nicotianae)和瓜果腐霉(Pythium aphani-dermatum),其中黄花蒿对真菌菌丝生长、多枝柽柳对稻瘟病菌孢子萌发表现出强的抑制活性。本研究为植物病害防治和新疆植物资源的开发和利用提供了依据。  相似文献   

20.
Liu  Mengdie  Tang  Hui  Jiang  Huiwen  Li  Jie  Yan  Shoulei  Wang  Qingzhang 《International microbiology》2021,24(3):415-425
International Microbiology - Air discharge showed significant inhibition on mycelial growth and spore germination of Fusarium oxysporum, one of the main spoilage fungi in post-harvest lotus roots...  相似文献   

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