Melibiose

About: Melibiose is a research topic. Over the lifetime, 1002 publications have been published within this topic receiving 27300 citations. The topic is also known as: Melibiose.

Effect of lactic acid bacteria isolated from Tibetan Plateau on silage fermentation quality of Elms nutans

Abstract: OBJECTIVE In order to detect the effect of lactic acid bacteria isolated from Tibetan Plateau on silage fermentation quality of Elms nutans METHODS We used 3 isolated lactic acid bacteria with better growth at low temperatures of 10 and 15 degrees C at ensiling of Elymus nutans Subsequently, effects of the selected lactic acid bacteria on fermentation profiles of Elymus nutans silages stored at 15 and 25 degrees C were evaluated by using the same species of commercial inoculants as the control RESULTS PP-6 isolated from Tibetan Plateau could ferment raffinose, lactose, sorbitol, melibiose and sucrose, and LS-5 could ferment cottonseed sugar, laetrile, rhamnose, lactose, sorbitol, xylose, arabinose, melibiose and sucrose, but the same species of commercial strains could not use these sugars Inoculation of these three strains into Elymus nutans at 15 and 25 degrees C ensiled for 50 d, we found that LS-5 significantly reduced silage pH, propionic acid concentration and ratio of ammonia nitrogen/total nitrogen at 15 degrees C (P < 005), salvaged more water-soluble carbohydrate and crude protein; Application of LP-2 and PP-6 as a combined inoculant to Elymus nutans significantly improved lactic acid concentration (P < 005), resulting in a lower ratio of ammonia nitrogen/total nitrogen, saved more crude protein and significantly reduced neutral detergent fiber content (P < 005) as compared with the commercial strains CONCLUSION The three isolated strains can improve silage quality of Elymus nutans growing on the Qinghai-Tibetan Plateau at low temperature, but these strains have no obvious advantages at 25 degrees C in comparison with the commercial inoculants

A novel lactic acid bacterium and a method of preparing for onion beverage fermented by the same

Abstract: PURPOSE: Pediococcus pentosaceus which is a novel lactobacillus and a method for manufacturing an onion fermented liquid using the same are provided to ensure antioxidative and antibacterial activities and to produce a highly functional beverage. CONSTITUTION: Pediococcus pentosaceus(KFCC 11439P) is isolated from Kimchi and has an acid producing ability and lactic acid fermentation ability. The Pediococcus pentosaceus has a saccharide metabolic ability to rhamnose, melibiose, sucrose, raffinose, amygdalin, N-acetylglucosamine, and ribose. A method for manufacturing an onion fermented beverage comprises: a step of preparing onion fermenting liquid; a step of inoculating the onion fermenting liquid with Pediococcus pentosaceus; and a step of fermenting the onion fermenting liquid.

Galactosidase Activity ofLactose-positive Neisseria'

Abstract: (ONPG)was hydrolyzed bylactose-positive Neisseria. Eight strains ofpharyngeal origin were examined. Inculture reactions, sevenstrains resembled Neisseria meningitidis with theexception thattheyproduced acidfrom1% (w/v) lactose. An eighth strain (V8)differed inthatitdidnotformacidfrommaltose orfrom1% lactose. However,acidformation was observed in10%lactose cultures ofstrain V8,suggesting thatentryoflactose occurred bypassive diffusion, rather thanas a result of permeaseactivity. Theenzymeswhichhydrolyzed ONPG wereproduced constitutively bythecells ofalleight strains. Thus, specific activity inthese strains wasnotincreased byprior exposuretolactose, ortotwootherpossible inducers, isopropyl-:D-thiogalactoside ormethyl-3-D-thiogalactoside. Studyofcell-free extracts ofone strain showed that theenzymewasheat-labile, having a half-life of10minat45C. Theenzymewas unstable atlowprotein concentrations, butitwas protected completely orpartially whenalbumin ormanganousions wereadded. Theenzymeappeared tobeatypical 3-galactosidase: a-galactosides (melibiose andp-nitrophenyla-D-galactopyranoside) werenothydrolyzed, activity against ONPG was notdependent upon inorganic phosphate, andgalactose was released bycleavage of ONPG.ONPG hydrolysis provided a simple andrapid methodfordetecting lactose-positive Neisseria. Thecommonspecies ofNeisseria donottypically formacidfromlactose (Bergey's Manual). Nevertheless, lactose-positive strains havebeen described (13,15,16)whichbearconsiderable resemblance toNeisseria meningitidis. Asabasis forprojected genetic andtaxonomic studies of representative strains, theenzymatic action of these lactose-positive Neisseria onvarious galactosides wasexamined. Useofa chromogenic substrate, whichhasbeeninvaluable innumerous genetic investigations oflactose metabolism (1, 12), provided asensitive method fordetermining (3-galactosidase activity.

Determination of Monosaccharides and Soybean Oligosaccharides in White Vinegar and Tofu Water by Ion Chromatography and Pulsed Amperometric Detection

Abstract: A chromatographic method was developed for the determination of galactose, glucose, fructose, sucrose, melibiose, raffinose and stachyose in white vinegar and tofu water. These seven saccharides can be separated well in 30 min by CarboPac PA10 high performance anion exchange column(HPAEC) with sodium hydroxide gradient elution. The detection limits of galactose, glucose, fructose, sucrose, melibiose, raffinose and stachyose (25 mu L injection, S/N = 3) using Pulsed Amperometric Detection(PAD) are 3, 2, 3, 6, 4, 7 and 6 mu g/L, respectively. Moreover, all analytes have wide linearity range(0.02 - 20 mg/L), good relative standard deviations(0.2% - 3.2%) and satisfying recoveries(92% - 104%). This method is quite suitable for the determination of common saccharides in soybeans and soybean products for its simple and good separating performance as well as high sensitivity. No derivation is needed in the process of determination.

Kinetics and Mechanism of Oxidation of Melibiose and Cellobiose by Cu(NH3)42+ in Ammoniacal and Buffered Medium

Abstract: Kinetics of oxidation of maltose and lactose by cuprammonium-sulphate in ammoniacal and buffered medium have been studied. The rate of reaction is independent of [Cu] and directly proportional to [Disaccharide] and square root of [NH3], On addition of NH4C1 the reaction rate decreases due to common ion elfect. A probable mechanism involving the formation of an intermediate enediol anion has been proposed and the rate of enolization is the respective rate of oxidation. The activation parameters have been also evaluated. Introduction Earlier, the kinetics of oxidation of some reducing sugars by coppersulphate in presence [1, 2] and absence [3, 4] of complexing agents have been studied by SINGH et al. in strong alkaline medium. The reaction path showed a short induction period and autocatalysis due to produced finer colloidal particles of Cu 2 0. A general mechanism of oxidation based on the formation of an intermediate 1,2 Enediol has been suggested b y them. Later MARSHALL and WATERS [5] confirmed the results of SINGH et al. while studying the kinetics of oxidation of D-glucose, acetoin and Benzoin by alkaline coppersulphate complexed with tartrate, citrate and picolinate etc. by elucidating the rate expression as: -d[Cu\"] /dr = 2 K J E ] [Cu], and the rate-determining step assuming to be cuprous chelate formation. There after WIBERG and NIGH [6] studied the kinetics of oxidation of a-hydroxyacetophenone by cupric acetate in buffered aqueous pyridine medium spectrophotometrically and pointed out that the reaction follow the rate law: v = tf,[Ketol] + tf2[Ketol] [Cu]. The first term corresponds to the independently determined rate of enolization and second term is the major one when [Cu] is greater than 0.01 M. Thus they agree with the findings of SINGH et al. at lower concentration of copper sulphate. The present paper deals with the kinetics and mechanism of oxidation of Maltose and Lactose by cuprammonium-sulphate in ammoniacal and buffered medium. The system is advantageous as compared to copperchelate oxidants as it becomes homogeneous during entire course of oxidation due to formation of complex Cu(NH3)2. ' k.. C. GUPTA M