Solka-floc

Powdered Cellulose. Solka-Floc, a purified fibrous powdered ceUulose, is said to be 99% ceUulose on a dry weight basis, virtuaUy lignin free, free of fat and proteia, and with low ash content. Food grades are available ia fiber lengths averagiag 20—25 to 100—140 p.m. 

Perlite and Solka-floc are finely divided powders manufactured from a volcanic mineral and from wood pulp respectively, which have filtration properties very similar to those of diatomite. Like diatomite, they are inert to a wide range of process liquids. Like diatomite, they are available in a range of particle-size distributions to give the desired clarity and flowrate in different applications. On a cost-of-use basis, they are as economical as, or more economical than, diatomite. 

Although less known than diatomite, these products have been in wide use for many years so that there exists a sound body of applications knowledge upon which to base grade selection, dosage, and procedures. Perlite and Solka-floc have the same availability in bagged, semi-bulk, or bulk formats as diatomite. 

Table I. Comparison of Selected Biomass Species with Avicel and Solka-Floc (Percentage) ...

Because of its ability to produce and secrete the complete set of cellulolytic enzymes, thus making it particularly potent in hydrolyzing the cellulose polymer to glucose monomers, the soft-rot fungus Trichoderma, in particular T. reesei has been the focus of cellulase research for decades (8). The preferred substrates used by most researchers for cellulase production are pure celluloses such as Avicel, Solka-floc, and cotton (9). Cellulase production by Trichoderma is controlled by a complex metabolic regulation (10-12). Cellulose acts (indirectly) as an inducer for the production of cellulases. Expression of cellulases is furthermore subject to repres-... 

All chemicals were of analytical grade and obtained from Sigma (St. Louis, MO) with the exception of bacto agar, yeast extract and peptone which were obtained from Merck (Darmstadt, Germany), and D-glucose, which was obtained from VWR. Solka-floc, a delignified pine pulp serving as the cellulosic substrate, was obtained from Fiber Sales Development (Urbana, OH). For the preparation of solutions and media, distilled water was used. 

To be able to study cellulose (Solka-floc) degradation without microbial conversion of the sugars formed, separate hydrolysis experiments were carried out in stirred flasks without cells. The conditions in these experiments were the same as during the corresponding fermentation... 

After 67 h, cellulose in the form of Solka-floc was added as described above. There was an immediate increase in the CER at this point. The increase continued until t = 73 h, at which point there was a sharp decrease in CER. This did not coincide with complete depletion of glucose from the medium (Fig. 3). The enzyme activity increased continually up to a value of about 2.6 FPU/mL. This maximum coincided with the depletion of glucose and occurred at about t = 100 h. From the integrated area of the COz evolution (Fig. 1), one can estimate that the C02 evolved on cellulose was about 80% of the value obtained from glucose. 

FPU/mL) vs time for aerobic batch cultivation of T. reesei Rut-C30. The initial growth medium was a Mandels medium with 10 g/L of glucose as the carbon source. At t = 67 h, Solka-floc was added to a concentration of 10 g/L. 

Fig. 4. Concentration of glucose (— —) and cellobiose (— —) during enzymatic hydrolysis of Solka-floc. The enzyme was prepared from a culture of T. reesei and the initial enzyme loading corresponded to 27.4 FPU/g substrate. Hydrolysis was carried out at 28°C and pH 5.0.

The Power Law parameters for the corn stover suspensions could not be located in previous studies. Dronawat (13). studied a similar system using filamentous particles (Solka-Floc with a fiber length 215 pm in... 

Many reseachers have previously studied the use of ultrafiltration to recycle cellulase during saccharification (5-22). However, much of this previous work involved either purified cellulosic substrates, such as Solka-Floc, which are not representative of feedstocks in large-scale operations, or lignocellulosic substrates at concentrations that would be much too low to be economical in a full-scale process. 

ONOZUKA P 500 PYROCELLULOSE RAYOPH-ANE RAYWEB Q REXCEL SIGMACELL Q SOLKA-FIL SOLKA-FLOC SOLKA-FLOC BW SOLKA-FLOC BW 20 SOLKA-FLOC BW 100 SOLKA-FLOC BW 200 SOLKA-FLOC BW 2030 SPARTOSE OM-22 SULFITE CELLULOSE TOMOFAN TUNICIN WHATMAN CC-31... 

Cellulose Avicel, Methocel, Solka-Floc, Cellulose gel, Just Fiber Mayonnaise, salad dressings, frozen desserts, processed cheese, fried foods, sauces... 

Arboceh, E460 Elcema-, Sanacel Solka-Floc. 

V Powdered cellulose Solka-Floc Fine Granular, Lot no. 9-10-8)... 

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