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1.
Low cost fermentation media using agricultural by-products (wheat bran extract, rice bran extract and soybean meal extract) as a major nutrient source, were evaluated for the production of tyrosinase from the fungus Auricularia auricula in submerged culture. In single-factor experiments, three components (wheat bran extract, casein and CuSO4) were chosen to further optimize medium composition using response surface methodology (RSM). The central composite experimental results showed the following optimum medium composition: wheat bran extract 36.0 %, casein 1.1 g/l and CuSO4 0.13 g/l. Under these conditions, the highest tyrosinase activity was 17.22 U/ml, which was 2.1 fold higher than that obtained using the non-optimized medium. The present study is the first to report the statistical optimization of medium composition for production of tyrosinase by A. auricula using cheaper wheat bran extract as a major nutrient source. These results might provide a reference for the development of a cost-effective medium for commercial production of tyrosinase.  相似文献   

2.
The major components (50%) of the surface lipid extract of fungal spores (5.6% of dry spore wt) of Sphaerotheca fuliginea are esters of primary alcohols and fatty acids. Esters (15%) of primary alcohols and a Δ2t acid are present. The major acid moieties of the alkyl esters are C22 and C24 and of the Δ2t alkyl ester is Δ2t C22; for both classes eicosanol is the major primary alcohol. The major ester of each class was concluded to be eicosanyl docosanoate and eicosanyl trans-2-docosenoate. Minor components are saturated and Δ2t methyl and diol diesters and free fatty acids. The major acid moieties of the diol diesters are C22 and C24 and the major diol is 1,12-dodecanediol.  相似文献   

3.
The total surface lipids, including the wax particles, of the adult whiteflies of Bemisia tabaci and Trialeurodes vaporariorum were characterized. At eclosion, there were similar amounts of long-chain hydrocarbons, aldehydes, alcohols and wax esters. Within a few hours post-eclosion, long-chain aldehydes and long-chain alcohols were the dominant surface lipid components, C34 on B. tabaci and C32 on T. vaporariorum. Hydrocarbons, mainly n-alkanes, were minor components of the surface lipids. The major wax esters were C46 on B. tabaci and C42 on T. vaporariorum. The major acid and alcohol moieties in the wax esters of B. tabaci were C20 and C26, respectively, and of T. vaporariorum were C20 and C22, respectively. Both B. tabaci and T. vaporariorum had a minor wax ester composed of the fatty acid C18:1 esterified to the major alcohols, C34 and C32, respectively. Bemisia were readily distinguished from Trialeurodes based on the composition of their wax particles and/or their wax esters; however, no differentiating surface lipid components were detected between biotypes A and B of B. tabaci.  相似文献   

4.
The effect of a saponin-rich extract from rhizomes of Soapwort (Saponaria officinalis L) and four synthetic surfactants: sodium lauryl sulphate (SLS), sodium laureth sulphate (SLES), ammonium lauryl sulphate (ALS) and cocamidopropyl betaine (CAPB) on two model lipid monolayers is analyzed using surface pressure, surface dilatational rheology and fluorescence microscopy. The following monolayers were employed: dipalmitoylphosphatidylcholine/cholesterol mixture in a molar ratio of 7:3 (DPPC/CHOL) and Ceramide [AP]/stearic acid/cholesterol in a molar ratio of 14:14:10 (CER/SA/CHOL). They mimicked a general bilayer structure and an intercellular lipid mixture, respectively. Both lipid mixtures on Milli-Q water were first compressed to the initial surface pressure, Π0 = 30 mN/m and then the subphase was exchanged with the respective (bio)surfactant solution at 1% (w/w). All four synthetic surfactants behaved in a similar way: they increased surface pressure to about 40 mN/m and reduced the storage modulus of surface dilational surface rheology, E′, to the values close to zero. The corresponding fluorescence microscopy pictures confirmed that the lipids mimicking the stratum corneum components were almost completely removed by the synthetic surfactants under the present experimental conditions. The components of the Soapwort extract (SAP) increased surface pressure to significantly higher values than the synthetic surfactants, but even more spectacular increase was observed for the storage modulus of the SAP-penetrated lipid monolayers (up to E′= 715 mN/m).  相似文献   

5.
Pasteuria penetrans spore adhesion to Meloidogyne javanica second-stage juveniles (J2) was examined following several different pretreatments of the latter. The detergents sodium dodecyl sulfate and Triton X-100, the carbohydrates fucose and α-methyl-D-mannoside, and the lectins concanavalin A and wheat germ agglutinin reduced spore attachment. Spores exposed to M. javanica surface coat (SC) extract exhibited decreased adherence to the J2 surface. Second-stage juveniles that had been treated with antibodies recognizing a 250-kDa antigen of J2 SC extract had fewer spores attached to their surfaces, as compared to nontreated J2, except in the head region. This inhibition pattern was similar to that of antibody-labelling on M. javanica J2 as observed by electron microscopy. It is suggested that several SC components, such as carbohydrate residues, carbohydrate-recognition domains, and a 250-kDa antigen, are involved in P. penetrans spore attachment to the surface of M. javanica.  相似文献   

6.
Fluids isolated from the testis, seminal vesicle, uterus, and pseudocoelomic cavity of Ascaris suum were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and measured for protein concentration, pH, and osmolarity. The testis and seminal fluids display much homology and share major polypeptide components having molecular weights of 15,000 and 35,000. A cytoplasmic extract of spermatids from the seminal vesicle exhibited a banding pattern nearly identical to that of testis fluid. The seminal fluid has unique major components of 57,000 and 150,000, and seminal fluid from individual worms showed differences in major band concentration and distribution of minor components. The uterine fluid has major polypeptides of 14,000, 16,000, 66,000, 74,000, 120,000, and 140,000, and exhibits more similarity to the perienteric fluid then either the seminal or testis fluids. Electrophoretic comparisons of four uterine regions revealed nearly identical banding patterns although somewhat higher concentrations of four major components occurred in certain segments. The male and female perienteric fluids have major bands at 40,000, 120,000, and 140,000, and the female fluid has more intense minor components of 90,000 and 115,000. Perienteric fluid from individual worms differed only in minor band distribution. The reproductive fluids have numerous minor components mostly from 20,000 to 70,000, while the perienteric fluid minor bands are mainly located in the 80,000 to 120,000 range. The pH of the seminal fluid (6.5) differs from that of the uterine fluid (7.7), and both seminal and uterine fluids are of lower osmolarity than the perienteric fluid. In vitro studies demonstrate that uterine fluid does not induce spermatid transformation into bipolar, ameboid spermatozoa, while the seminal fluid induces only lipid granule coalescence in either seminal vesicle or terminal testis spermatids.  相似文献   

7.
8.
The pupal parasitoidBrachymeria intermedia (Nees) was reared from the egg to adult stage on artificial media based on commercial meat homogenates for babies (Plasmon®), either with or devoid of host components. Six media containing 80% homogenate and 20% extract ofGalleria mellonella L. pupae were tested first. Two types of homogenates, intended for babies at the beginning of weaning (a) and well on in weaning (b), were utilized. Media were based on beef, veal and chicken meat, 3 on a-homogenates and 3 on b-homogenates. A significantly higher percentage of parasitoids developed as mature larvae on the a- than on the b-homogenate based diets. This was presumably related to the higher protein, carbohydrate, lipid and calorie level of the a- than of the b- homogenates. Diet veal-a produced the best mean adult yield (27.4%). Other two diets based on the veal-a homogenate were then tested. The first, composed of 80% homogenate, 10% host pupal extract, 7% chicken egg yolk, 1.5% yeast extract and 1.5% wheat germ, produced a mean adult yield of 66.7%, similar to that obtained inG. mellonella pupae. On the second medium, devoid of host components and containing 85% veal-a homogenate, 10% chicken egg yolk, 2.5% wheat germ and 2.5% yeast extract, the mean adult yield was 22.5%. In all media, the adults obtained were viable and fecund.  相似文献   

9.
The choline-containing phosphoglycolipid, MfGL-II, is the major polar lipid of Mycoplasma fermentans PG18. Anti-MfGL-II antisera raised in rabbits using the purified MfGL-II as an immunogen were employed in immunogold electron microscopic and immunofluorescence studies showing that MfGL-II is uniformly distributed and exposed on the cell surface of M. fermentans cells. The specificity of the antibodies was determined by immunostaining of lipid extracts separated by thin layer chromatography. The antibodies recognize lipids specific to M. fermentans but did not cross-react with lipid extracts of M. penetrans, M. capricolum, M. gallisepticum or Acholeplasma laidlawii. As phosphocholine almost completely abolished antibody interaction with MfGL-II in an ELISA assay it is suggested that the anti-MfGL-II repertoire is composed primarily of anti-phosphocholine antibodies. The anti-MfGL-II antisera inhibit the attachment of M. fermentans to Molt-3 lymphocytes suggesting that MfGL-II plays a major role in M. fermentans-host cell interaction.  相似文献   

10.
Human platelet glycoproteins were isolated from whole platelets by two methods. The first method, that of affinity chromatography on wheat germ agglutinin, is based on the known affinity of lectins for cell surface glycoproteins. When solubilized whole platelets are used as starting material for this procedure, elution with N-acetylglucosamine yields primarily a glycoprotein of Mr ≈ 150 000 as estimated by sodium dodecyl sulfate-acrylamide gel electrophoresis. The second method is based on the ability of the chaotropic salt lithium diiodosalicylate to extract glycoprotein from particulate cell fractions in water-soluble form. This method yields three major glycopeptides with apparent molecular weights after sulfhydryl reduction of 145 000, 125 000, and 95 000 as estimated on 5.6% sodium dodecyl sulfate-acrylamide gels. Carboxymethylation of these preparations in the presence of sulfhydryl-reducing agent further resolves a glycoprotein of Mr ≈ 165 000.Treatment of whole platelets by periodate oxidation and sodium[3H]borohydride reduction labels the three major glycoproteins extracted by lithium diiodosalicylate and the glycoprotein of Mr ≈ 150 000 isolated on wheat germ agglutinin confirming their surface orientation. However, glycoprotein with Mr ≈ 165 000 resolved by carboxymethylation of the lithium diiodosalicylate extracted glycoprotein mixture was not labelled by this method, suggesting that it represents the granule protein with similar electrophoretic characteristics described by others.Phosphorylation of intact platelets with 32Pi also results in labelling of glycoproteins isolated by both methods, suggesting that these molecules traverse the  相似文献   

11.
Three membrane-bound cytochromes from the photosynthetic purple sulfur bacterium Chromatium vinosum have been partially separated from other membrane components by treatment with deoxycholate followed by ammonium sulfate fractionation and chromatography on Bio-Gel A1.5. Cytochrome c555, present in relatively small amounts in the deoxycholate extract, has an α-band that splits into two bands at 548 and 552.5 nm at liquid nitrogen temperature. The major components of the deoxycholate extract are cytochromes c553 and b560, which are present in essentially equimolar amounts through all the stages of the purification procedure.  相似文献   

12.
Hypercholesterolemia and oxidative stress are known to accelerate coronary artery disease and progression of atherosclerotic lesions. In the present study, an attempt was made to evaluate the putative antihypercholesterolemic and antioxidative effects of an ethanolic extract of the oyster mushroom (Pleurotus ostreatus) and chrysin, one of its major components, in hypercholesterolemic rats. Hypercholesterolemia was induced in rats by a single intraperitoneal injection of Triton WR-1339 (300 mg/kg body weight (b.wt.)), which resulted in persistently elevated blood/serum levels of glucose, lipid profile parameters (total cholesterol, triglycerides, low-density lipoprotein-, and very low-density lipoprotein-cholesterol), and of hepatic marker enzymes (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase). In addition, lowered mean activities of hepatic antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase) and lowered mean levels of nonenzymatic antioxidants (reduced glutathione, vitamin C, and vitamin E) were observed. Oral administration of the mushroom extract (500 mg/kg b.wt.) and chrysin (200 mg/kg b.wt.) to hypercholesterolemic rats for 7 days resulted in a significant decrease in mean blood/serum levels of glucose, lipid profile parameters, and hepatic marker enzymes and a concomitant increase in enzymatic and nonenzymatic antioxidant parameters. The hypercholesterolemia-ameliorating effect was more pronounced in chrysin-treated rats than in extract-treated rats, being almost as effective as that of the standard lipid-lowering drug, lovastatin (10 mg/kg b.wt.). These results suggest that chrysin, a major component of the oyster mushroom extract, may protect against the hypercholesterolemia and elevated serum hepatic marker enzyme levels induced in rats injected with Triton WR-1339.  相似文献   

13.
Skin tissue, in addition to its specific use in dermal research, provides an excellent model for developing the techniques of vibrational microscopy and imaging for biomedical applications. In addition to permitting characterization of various regions of skin, the relative paucity of major biological constituents in the stratum corneum (the outermost layer of skin), permits us to image, with microscopic resolution, conformational alterations and concentration variations in both the lipid and protein components. Thus we are able to monitor the effects of exogenous materials such as models for drug delivery agents (liposomes) and permeation enhancers (DMSO) on stratum corneum lipid organization and protein structure. In addition, we are able to monitor protein conformational changes in single corneocytes. The current article demonstrates these procedures, ranging from direct univariate measures of lipid chain conformational disorder, to factor analysis which permits us to image conformational differences between liposomes that have permeated through the stratum corneum from those which have remained on the surface in a reservoir outside the skin.  相似文献   

14.
《Plant science》2007,172(3):579-587
Tryptophanins (TRPs) are low molecular weight, tryptophan-rich, basic proteins found in oat (Avena sativa L.) seeds. Like their counterpart puroindolines (PINs) from wheat (Triticum aestivum L.), TRPs are thought to be involved in flour softness as well as disease resistance against phytopathogenic fungi. PINs are known to be the major components of ‘friabilin’ associated with the surface of water washed starch grains and possess lipid binding properties. Two polyclonal antisera against puroindoline-a (PIN-a), and puroindoline-b (PIN-b) respectively; and a monoclonal antiserum raised against ‘friabilin’ were used as primary antibodies in immunoblotting experiments. All antisera detected immunoreactive polypeptides, with approximate relative masses of 15–16 kDa, in oat, wheat, and barley (Hordeum vulgare L.) seed extracts but not in rice (Oryza sativa L.), maize (Zea mays L.), bean (Phaseolus vulgaris L.), pea (Pisum sativum L.) and lentil (Lens culinaris Medic.) seed extracts. Immunoreactive polypeptides were detected in aqueous ethanol [52% (v/v) ethanol] seed extracts. Both anti-‘friabilin’ monoclonal and anti-PIN-b polyclonal antisera recognized 15 as well as 16 kDa tryptophanins in oat seeds from different cultivars. On the other hand, anti-PIN-a polyclonal antiserum strongly cross-reacted with 16 kDa TRP and weakly with 15 kDa TRP. Tryptophanins were found to be associated with the surface of starch grains in oat endosperm tissue using both fluorescence and confocal laser scanning microscopies with anti-‘friabilin’ monoclonal antiserum. SDS-PAGE and immunoblotting assays revealed a gradual synthesis of TRPs as early as milk stage in developing oat seeds. On the other hand, TRPs tend to undergo degradation during seed germination.  相似文献   

15.
In this study, antimicrobial properties of both lyophilized and fresh water extracts of the okra pods were assessed against Rhodococcus erythropolis and R. opacus, Mycobacterium sp. and M. aurum, Staphylococcus aureus, Escherichia coli, and Xanthobacter Py2. The extracts were effective against all bacterial strains tested, except R. erythropolis and the fresh extract displayed better antimicrobial properties than the lyophilized extract. A fresh extract concentration of 97.7 mg/mL was sufficient to kill all S. aureus cells, which is a worldwide source of nosocomial infection. The extract was also effective in inhibiting the growth of both Mycobacterium strains, X. Py2 and S. aureus, but was ineffective against R. erythropolis and E. coli. The lipid fraction of the okra gum was found to be responsible for the antibacterial properties and the protein and polysaccharide fractions displayed no antimicrobial activity. The two major constituents of the lipid fraction, palmitic and stearic acids, were apparently responsible for the antimicrobial properties of the okra extract.  相似文献   

16.
The parasitizing stage (trophozoite) of the protozoan parasite Perkinsus olseni progresses to the dormant stage (prezoosporangium) immediately after the death of the host through physiologically and morphologically drastic changes. This development is reproducible in Ray's fluid thioglycollate medium (RFTM). In this study, supplementation with tissue extract from a host, the Manila clam, significantly improved the efficiency of development, as determined by the numbers and sizes of developed prezoosporangia. Similar results were seen following supplementation with boiled host tissue extract, which indicates that a thermally stable component of the host is required for the parasite's development. Subsequently, we found that a commercially available lipid concentrate significantly increased prezoosporulation without host tissue, suggesting that the lipids in host tissue enhance prezoosporangia development. Moreover, we determined that yeast extract, sodium thioglycollate, and sodium chloride were the only components of RFTM required for prezoosporulation. Based on these findings, we prepared a simple, host-free medium for P. olseni prezoosporulation—Lipid concentrate Yeast extract Medium (LpcYM)—consisting of yeast extract, lipid concentrate, sodium thioglycollate, and sodium chloride. We confirmed that the prezoosporangia developed in LpcYM produce zoospores that are infectious to Manila clams and that trophozoites of other Perkinsus species (P. marinus, P. honshuensis, and P. chesapeaki) also develop to prezoosporangia in this host-free medium. As LpcYM has the simplest composition of prezoosporulation media available thus far, it enables us to conduct molecular and biochemical studies examining the drastic transformation process of this parasite.  相似文献   

17.
Inhibition of protein synthesis by products of lipid peroxidation   总被引:1,自引:0,他引:1  
Effects of lipid peroxidation products on in vivo and in vitro protein synthesis have been studied. Malondialdehyde (MDA), a product, and a routinely used index of lipid peroxidation, inhibits in vivo protein synthesis in the two mosses, Tortula ruralis and Cratoneuron filicinum, and in pea (Pisum sativum) leaf discs. When wheat germ supernatant or poly(A)-rich mRNA of T. ruralis was incubated with MDA its subsequent activity in a cell-free protein-synthesizing system was reduced. When MDA was added directly to the in vitro protein-synthesizing mixture containing moss polyribosomes, the inhibition of amino acid incorporation was small. However, when simultaneous lipid peroxidation was allowed to occur along with in vitro protein synthesis there was a strong inhibition of amino acid incorporation and MDA accumulated in the reaction mixture indicating that products of lipid peroxidation other than, and apparently more toxic than, MDA were involved. It was concluded that lipid peroxidation inhibits protein synthesis probably by releasing toxic products which may react with and inactivate some components of the protein-synthesizing complex.  相似文献   

18.
Exceptionally large amounts of lipid are stored in flight muscles of Rhodnius prolixus and Triatoma infestans (197 and 90 μmoles glyceride glycerol per g fresh weight respectively). The bulk of this lipid is in the form of triacylglycerol.A significant decrease in the muscle lipid occurs during the first hour of flight. Over the same period there is an increase in haemolymph lipid (particularly of diacylglycerol) which is taken to indicate the use of lipid from the fat body. The carbohydrate content of muscle and haemolymph is low, so it is likely that the supply of energy for flight is provided almost exclusively by the oxidation of fat. Oleate and palmitate are the major fatty acid components of lipid from both Triatoma and Rhodnius and are probably also the major fatty acids used for oxidation.Maturation of flight ability is temporally associated with the development of flight muscle size and increase in glyceride content.  相似文献   

19.
  • 1.1. The concentration of protein in the haemolymph of Balanus hameri ranged from 2.0 to 17.3 mg/ml, and the lipid from 1.4 to 7.7 mg/ml; the haemolymph protein and lipid levels increased significantly prior to cross-fertilization.
  • 2.2. The protein and lipid concentrations in Balanus balanus haemolymph were 8.1 and 1.7 mg/ml respectively.
  • 3.3. The lipid concentration of Lepas anatifera haemolymph was 1.2 mg/ml.
  • 4.4. The neutral lipid and phospholipid components of B. hameri and L. anatifera haemolymph were the same, with the major components of the phospholipid fraction being phosphatidyl ethanolamine and phosphatidyl choline.
  • 5.5. The osmolarity (970.4 mOsm), chloride ion concentration (501.3 m-eq/l) and pH (7.29) of B. hameri haemolymph were also determined.
  相似文献   

20.
Thousand-kernel weight (TKW) is one of the major components of grain yield in wheat (Triticum aestivum). Identifying major quantitative trait loci (QTLs) for TKW and developing effective markers are prerequisite for success in marker-assisted selection (MAS) to improve wheat yield through breeding. This study mapped a major QTL, designated as TaTKW-7AL, for increasing TKW on the long arm of chromosome 7A of ‘Clark’ to a 1.3-cM interval between single nucleotide polymorphism (SNP) markers IWB13913 and IWA5913. This QTL explained 19.7 % of the phenotypic variation for TKW. A QTL for increasing kernel length (KL), one of the major components of TKW, was mapped in the same interval as TaTKW-7AL, suggesting that increased TKW by the QTL in ‘Clark’ is most likely due to the increased KL. Association analysis on a diversity panel of 200 US winter wheat accessions also identified a haplotype of three SNP markers (IWB13913, IWB6693 and IWA5913) that were tightly associated with the both KL and TKW. The analysis of allele frequencies of the haplotype in the diversity panel suggested that the favorable allele of TaTKW-7AL has not been strongly selected for in practice and has potential to be used to improve grain yield in US hard winter wheat breeding. Two user-friendly flanking KASPar markers, IWB13913 and IWA5913, were developed for MAS of TaTKW-7AL.  相似文献   

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