The traditional filter paper assay for saccharifying cellulase
originally described by M. Mandels et al (1976) has been modified to
make possible low activity determinations of Trichoderma
cellulases. The enzymatic activity appears to decline during a
prolonged incubation period if no precautions have been taken. By
means of adding bovine serum albumin and potassium chloride as
protein stabilizers and sodium azide as an antimicrobial agent filter
paper activities in the range from 0.02 to 0.37 (IUPAC assay, 1987)
can be estimated by extending the incubation time up to 20 hours. Filter paper activity values obtained by this method may be
compared to those obtained by the IUPAC assay by using a conversion
factor from 1.4 to 1.7.
Acid whey and sweet whey permeate have been investigated as
media for growth and metabolite production by Trichoderma reesei
QM 9414 using shake flask cultures and spore inocula. In the case of
acid whey the mycelial growth after 2 weeks is 13 mg dry weight
/ml substrate. The specific growth rate is 0.29/day. The fungus
appears to metabolize the whey protein the first 2 weeks. The
alkalinity of acid whey rises continuously over a three week period
up to a pH of 8.5. In the case of whey permeate the maximal mycelial
weight gain is 4.4 mg/ml which appears after 8 days. A rise in net
soluble protein level comes after 3-5 days and reaches a maximum
value of 0.23 mg/ml after 2 weeks. The pH of whey permeate rises
continuously to 7.5 after 3 days and then slowly declines. The net
production of cellulases is low on both media. Dilution 1:6 of the
acid whey, supplementation with ammonium sulfate and pHadjustments
did not enhance the production of cellulases. Acid
whey supports a significant growth and sweet whey permeate shows
potential for extracellular protein production.
A literature review surveys the composition and uses of acid
whey, environmental aspects of whey wastes, the fungus
Trichoderma reesei, the mode of action of the Trichoderma reesei
cellulase system and the structure of cellulose in cotton and wood. / Graduation date: 1994
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/27236 |
| Date | 24 November 1993 |
| Creators | Nordmark, Tor Soren |
| Contributors | Penner, Michael H. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
Page generated in 0.0081 seconds