Cellulase yielding

The first group is comprised that of compounds which potentially could be degraded to form G-l-P by phosphorolysis by beta-linkage specific enzymes. They include IPTGlu, cellobiose, sophorose, salicin, and sucrose. Addition of these compounds, or exogenous G-l-P, to Solka Floe fermentations improved maximum cellulase yields from 171 to 309%, and the time period for enzyme synthesis was reduced from 95 to 59% compared with using Solka Floe only. 

The same researchers studied glucose production using beta-glucosidase immobilized with the same hydrophilic foam (Hypol 2002). " The immobilized enzyme showed 95% retention of activity after 1000 hours of continuous use at 23°C. Co-immobilization with cellulase yielded a cellulose-hydrolyzing complex with a... 

None of the six enzymes cleaved cellobiose, but in comparing the products released from swollen Avicel by hydrocellulase C with those from cellulodextrin by the Cellulases, further evidence of contamination of cellulases II and III was found. For the latter cases both glucose and cellobiose are produced whereas both hydrocellulase C and Cellulase IV yield predominantly cellobiose. Cellulase IV produced much more cellobiose than glucose from cellotetraose whereas the other Cellulases yielded only slightly more cellobiose than glucose. 

The obvious advantage of lactose over cellulose as carbon sources for fermentations is that it is soluble, an attribute which facilitates the downstream processing of recombinant proteins, and it is therefore often used as inducing carbon source in combination with the strong cellulase promoters (Kubicek and Harman 1998 Penttila et aL 2004). Although cellulase yields produced on lactose are usually reported to be lower compared to cellulose (Andreotti et al. 1980), it should be noted that the highest amount of cellulases produced by the publicly available T. reesei strain RUT C30 (Durand et al. 1988) was achieved on lactose as a carbon source. 

Fig. 1 Time couise of lactic acid yield and its concentration in SSF with or without pretreatment using 0.1 mol/l FICI with heating at 121 1 for 30 min. Famentation conditions 3TC, pH=5.0, initial load of bean curd refiise(BCR) 10 g, cellulase amount=l gin ILsuspension.

Marigold petals are rich sources of xanthophyUs, mainly lutein esters. To increase the coloring power, chemical extraction of the colorant from flower meal is performed or a new enzymatic procedure is applied. It was shown that treatment with cellulases or mixed saprophyte microorganisms or solid state fermentation improved the xanthophyll extraction yield. ... 

In one study [90], enzyme pretreatment increased colour yield without affecting fastness properties. However, pretreatment of cellulosic fibres with cellulase lowered the subsequent fixation of homobifunctional triazine reactive dyes but did not impair the fixation of other types of reactive dyes [91]. Another study suggested that the enhanced brightness of reactive dyeings was greater with triazine dyes than with vinylsulphone types when cotton was pretreated or aftertreated with cellulase [92]. 

FIG. 1 Effect of different enzymes or combination of enzymes (cellulases, xylanases, cellobiases, 3-glucanases, and proteases) on starch yield in the conventional corn wet milling process. 

Assays for endo-l,4- -glucanase [EC 3.2.1.4] (i.e., CMCase) and saccharifying cellulase (i.e., international filter paper U, IFPU) activities partially followed the methods recommended in the 1987 lUPAC report (65). When even undiluted enzyme samples fail to give the required glucose yield under prescribed assay conditions, the lUPAC committee recommends a less precise method. In the current study, cellulase activities in digester extracts were so low that the CMCU could only be defined as follows one CMC unit of activity was that amount of enzyme required to liberate one Hg glucose from CMC in 60 min. 

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