| Identification | Back Directory | [Name]
WELAN GUM | [CAS]
96949-22-3 | [Synonyms]
wlj
dyj
welan
Biozan
elangum
WELAN GUM
Fixed gel
weilanjiao
Wenlaixiao
wenlunjiao
wenlaijiao
Brunei gum
Warm rubber
weilangjiao
Kelco Crete
Sizing glue
KELCO-VIS DG
alcaligenessp
Welan gum H80
WELAN GUM ISO 9001：2015 REACH | [EINECS(EC#)]
619-250-2 |
| Questions And Answer | Back Directory | [Preparation]
method for extracting WELAN GUM from WELAN GUM fermentation broth involves centrifuging and extracting the fermentation broth to obtain the WELAN GUM. The method includes the following steps: A. Fermentation Broth Pretreatment A1. At pH 6-8, add lysozyme with an activity of 100,000 u/g to the fermentation broth. The concentration of lysozyme in the fermentation broth is 100-200 ppm. After stirring evenly, maintain the reaction for 3-5 hours. A2. Heat the fermentation broth from step A1 to 130℃-140℃, maintain for 5-8 minutes, then lower to 60-70℃. Add acidic protease with an activity of 50,000 u/g. The concentration of acidic protease in the fermentation broth is 200-400 ppm. React at pH 3-4 and a temperature of 50℃-60℃ for 2-4 hours to obtain the pretreated fermentation broth. B. First Extraction: Mix the pretreated fermentation broth with an ethanol solution containing at least 85% (v/v) at a ratio of 1:0.5-0.6, and stir for 30-40 minutes. Adjust the pH of the mixture to 8.0-9.5 to allow the gel to precipitate as flocculent precipitate. C. First Centrifugation: Separate the solid and liquid components of the mixture from step B to obtain fibrous gel. D. Second Extraction: Mix the fibrous gel prepared in step C with an ethanol solution containing at least 85% (v/v) at a ratio of 1:0.3-0.5, and stir for 30-35 minutes. Adjust the pH of the mixture to 6.0-6.5 to allow the gel to precipitate as flocculent precipitate. E. Second Centrifugation: Separate the solid and liquid components of the mixture prepared in step D to obtain fibrous gel. F. Three-stage elution: Mix the fibrous gel prepared in step E with an ethanol solution containing at least 85% by volume in a ratio of 1:0.4-0.6, stir for 30-35 minutes, adjust the pH of the mixture to 6.0-6.5, causing the gel to precipitate as flocculent precipitate. Separate the mixture into solid and liquid phases to obtain the fibrous gel. |
| Hazard Information | Back Directory | [Description]
Welan gum is a microbial product that occupies an important position among extracellular polysaccharides due to its novel properties and potential applications. The biopolymer Welan gum is synthesised by a fermentation process mainly by alkali producing bacteria of the genus Alcaligenes sp. It consists of a tetrasaccharide backbone chain polymer containing L-mannose, L-rhamnose, D-glucose and D-glucuronic acid. It is an anionic polysaccharide and therefore has polyelectrolyte properties due to the presence of d-glucuronic acid in its chemical structure[1]. | [Uses]
Welan gum has commercial applications in the field of cement systems. It acts as a thickener, suspending agent, binder and emulsifier, stabiliser and viscosity builder. It also has potential applications in oil well drilling as it maintains its stability and viscosity at high temperatures[1]. | [References]
[1] VARINDER KAUR . Welan gum: Microbial production, characterization, and applications[J]. International Journal of Biological Macromolecules, 2014, 65: Pages 454-461. DOI:10.1016/j.ijbiomac.2014.01.061. |
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