scholarly journals ISOELECTRIC POINTS FOR THE MYCELIUM OF FUNGI

1924 ◽  
Vol 6 (3) ◽  
pp. 259-271 ◽  
Author(s):  
William J. Robbins

1. Mycelium of Rhizopus nigricans when stained with certain acid and basic dyes and washed with buffer mixtures of 0.1 M phosphoric acid and sodium hydroxide responded much like an amphoteric colloid with an isoelectric point near pH 5.0. 2. When grown on potato dextrose agar the reaction of which was varied with phosphoric acid the extent of colony growth of Rhizopus nigricans plotted against the initial Sörensen value of the agar produced a double maximum curve with the minimum between the two maxima at initial pH 5.2. 3. When grown in potato dextrose broth the reaction of which was varied with phosphoric acid the dry matter produced by Rhizopus nigricans plotted against the Sörensen value of the broth produced a double maximum curve with the minimum between the two maxima at initial pH 5.2 or average pH 4.9. 4. Mycelium of Rhizopus nigricans placed in buffer mixtures of 0.01 M phosphoric acid and sodium hydroxide of pH 4.1 to 6.3, changed the reaction in most cases toward greater alkalinity. 5. Mycelium of Fusarium lycopersici stained with certain acid and basic dyes and washed with buffer mixtures of 0.1 M phosphoric acid and sodium hydroxide responded much like an amphoteric colloid with an isoelectric point near pH 5.5.

1983 ◽  
Vol 63 (1) ◽  
pp. 155-162 ◽  
Author(s):  
L. KUNG Jr. ◽  
B. W. JESSE ◽  
J. W. THOMAS ◽  
J. T. HUBER ◽  
R. S. EMERY

Whole barley was treated with sodium hydroxide (NaOH) in laboratory trials. Dry matter disappearance from nylon bags in the rumen of whole barley treated with 2.5, 3.5, or 4.9% NaOH for 30 h was 59.6, 72.4, and 93.0%, respectively, compared with 82.2% for untreated ground barley. In a subsequent lactation trial, 24 Holstein cows (eight per treatment) were fed high moisture ground ear corn, high moisture rolled barley or high moisture whole barley treated with 3.5% NaOH. Milk persistencies tended to be greater for cows fed high moisture rolled barley, next for ground ear corn and least for NaOH-treated barley. Milk composition was similar for all treatments. Dry matter intake was greatest for cows fed ground ear corn and lower for those fed the barley diets. Alpha-linked glucose and pH of feces were similar for cows fed ground ear corn and high moisture rolled barley diets, but fecal pH was lower and alpha-linked glucose concentrations three times greater for NaOH-treated barley. Digestibility percents of dry matter, acid detergent fiber and nitrogen were 61.4, 25.3, 64.7 for ground ear corn; 64.4, 38.0, 67.1 for high moisture rolled barley; and 56.8, 43.2, 54.8 for NaOH-treated barley, respectively. Rumen grain turnover estimated by excretion of ytterbium in feces was greatest for NaOH-treated barley (9.09%/h), intermediate for ground ear corn (6.10%/h) and lowest for high moisture rolled barley (4.93%/h). Key words: Dairy, sodium hydroxide, high moisture grains


1941 ◽  
Vol 31 (4) ◽  
pp. 488-499 ◽  
Author(s):  
Grahame Williamson

The digestibility coefficients of old barley straw fed with a basal ration of oats, bran and maize to two adult horses and of the same straw after treatment by Beckmann's method were ascertained. The coefficients of the nitrogen-free extractives and the crude fibre of the untreated straw were 33·23 and 38·24 respectively and of the treated straw 54·14 and 63·71. There was a reduction in the digestibility of the small quantity of protein and fat.Taking into account the 14·5% of dry matter lost during treatment, the starch equivalent value of the treated material was somewhat higher than that of poor quality meadow hay.The digestibility coefficients were considerably lower for an immature horse previously maintained entirely on fresh grass.


Author(s):  
CLAUDIO LIMA AGUIAR ◽  
TOBIAS J. B. MENEZES

Avaliou-se a produção de celulases e xilanase de Aspergillus niger IZ9, crescido sobre bagaço de cana, quimicamente tratado, como substrato. Os tratamentos foram: solução de hidróxido de sódio a 4%, e solução de hidróxido de sódio a 4%, ácido fosfórico p.a. e vapor. A produção das enzimas celulolíticas (celulase total, endoglicanase e ­glicosidase) e xilanase foi observada nos bagaços tratados e nãotratado. O tratamento com solução de hidróxido de sódio a 4% promoveu maior indução de síntese da maioria das enzimas, com exceção de ­glicosidase, a qual apresentou produção semelhante para os bagaços tratados quimicamente. Abstract It was evaluated the production of cellulases and xylanase by Aspergillus niger IZ09 grown in a substrate consisted of chemically treated sugarcane bagasse. The treatments were: 4% sodium hydroxide solution and 4% sodium hydroxide solution, phosphoric acid and steam. The production of the cellulolytic enzymes (total cellulase, endoglycanase and B.CEPPA, Curitiba, v. 18, n. 1, jan./jun.2000 67 ­glucosidase) and xylanase was observed in the treated and nontreated bagasses. The treatment with 4% sodium hydroxide solution promoted a greater induction of the synthesis of the majority of the enzymes, with exception of ­glucosidase, which showed similar production for both chemically treated bagasses.


1998 ◽  
Vol 64 (2) ◽  
pp. 405-410 ◽  
Author(s):  
Scot E. Dowd ◽  
Suresh D. Pillai ◽  
Sookyun Wang ◽  
M. Yavuz Corapcioglu

ABSTRACT Many of the factors controlling viral transport and survival within the subsurface are still poorly understood. In order to identify the precise influence of viral isoelectric point on viral adsorption onto aquifer sediment material, we employed five different spherical bacteriophages (MS2, PRD1, Qβ, φX174, and PM2) having differing isoelectric points (pI 3.9, 4.2, 5.3, 6.6, and 7.3 respectively) in laboratory viral transport studies. We employed conventional batch flowthrough columns, as well as a novel continuously recirculating column, in these studies. In a 0.78-m batch flowthrough column, the smaller phages (MS2, φX174, and Qβ), which had similar diameters, exhibited maximum effluent concentration/initial concentration values that correlated exactly with their isoelectric points. In the continuously recirculating column, viral adsorption was negatively correlated with the isoelectric points of the viruses. A model of virus migration in the soil columns was created by using a one-dimensional transport model in which kinetic sorption was used. The data suggest that the isoelectric point of a virus is the predetermining factor controlling viral adsorption within aquifers. The data also suggest that when virus particles are more than 60 nm in diameter, viral dimensions become the overriding factor.


1999 ◽  
Vol 1999 ◽  
pp. 54-54 ◽  
Author(s):  
M. Lewis ◽  
B.G. Lowman ◽  
M. Ford

Wheat requires processing for feeding to cattle otherwise large amount remain undigested. Processing methods can be mechanical or chemical (sodium hydroxide or aqueous ammonia) but these require specialised equipment and/or the use of contractors. The objective of this trial was to evaluate moist wheat fed whole, but treated with urea at harvest as a means of generating ammonia in situ, in diets for intensively finished cattle.Eighty tonnes of wheat (variety Riband) was harvested on 21-22 August 1997 at a dry matter (DM) of 750 g/kg and treated immediately with 53 l/tonne of a urea solution (430 g urea/litre) to supply 30 g urea/kg wheat DM. Treatment was achieved by applying the urea to the wheat as it was augered into the storage silo, which was then sealed with polythene.


1995 ◽  
Vol 89 (5) ◽  
pp. 487-495 ◽  
Author(s):  
M. Susan Monteith ◽  
Tao Wang ◽  
Morris J. Brown

1. We have previously reported the relative mRNA and protein level of the long and short splice variants of Gsα (GsαL and GsαS) in human atrium. We have now measured the relative proportions of the serine+ and serine− variants of GsαL and GsαS in human atrium, and assessed, indirectly, whether their differential expression may (i) regulate Gsα phosphorylation, and (ii) be regulated by atrial cyclic AMP levels. 2. The serine+ and serine− variants of GsαL and GsαS were estimated by single nucleotide primer extension in 36 right atrial strips of which half were from β-adrenoceptor-blocked patients. The ratio of serine+ to serine− variants was 0.06 ± 0.12 for GsαL, compared with 8.04 ± 12.16 for GsαS (P < 0.001). 3. Isoelectric points of GsαL and GsαS in the atria of four β-adrenoceptor-blocked and four non-β-adrenoceptor-blocked patients were estimated by two-dimensional gel electrophoresis. Two-dimensional gel analysis gave a consistent pattern with several spots for both GsαL and GsαS; however, the isoelectric points of GsαS were more acid (5.18 ± 0.24) than those of GsαL (5.87 ± 0.17, P < 0.001). 4. No significant difference in either the serine variants or isoelectric point value was observed between β-adrenoceptor-blocked and non-β-adrenoceptor-blocked patients. 5. In conclusion, all four Gsα variants were expressed in human atrium, but GsαL is almost entirely of the serine− form. GsαS has a more acidic isoelectric point than GsαL, indicating a possible post-translational modification. The lack of difference in our results between β-adrenoceptor-blocked and non-β-adrenoceptor-blocked patients suggests indirectly that cyclic AMP is an unlikely candidate for regulating splicing or post-translational modification of Gsα in vivo.


1990 ◽  
Vol 51 (1) ◽  
pp. 217-219 ◽  
Author(s):  
F. J. Hart ◽  
Jane Leibholz

Three steers cannulated in the rumen and abomasum were given a diet of wheat straw, chopped and soaked in sodium hydroxide and then washed to pH less than 8. The straw was sprayed with sucrose, urea and minerals. The diet was free of digestible protein and given at 1·7 to 4·1 kg/day. Microbial protein flowing to the omasum was measured by 15N. By difference, the flow of endogenous protein nitrogen to the omasum was found to be 2·2 g/kg dry-matter intake. The flow of endogenous protein nitrogen to the abomasum was 3·3 to 9·4 g/kg dry-matter intake, and it decreased with increasing food intake.


Author(s):  
A. P. Moloney ◽  
A. V. Flynn

Treatment of poor quality roughages with ammonia or sodium hydroxide (NaOH) has been demonstrated in numerous studies to improve the nutritive value of these materials. Ammonia is usually applied in anhydrous or aqueous forms in stacks at ambient temperature or anhydrous in high temperature ovens (e.g. Mason et al., 1989) while NaOH is usually applied as an aqueous solution either as a spray or by immersion of the test material (e.g. Wanapat et al., 1985). The objective of this study was to determine the effects on composition and subsequent rumen fermentation when low digestibility grass hay was treated with ammonia and/or NaOH by a procedure which might be readily used at farm level.


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