Utilisation of whole wheat flour for the production of extracellular pectinases by some fungal strains

A safe potential juice clarifying pectinase from Trichoderma viride EF-8 utilizing Egyptian onion skins

The production of a notable, safe and highly active pectinase by the local fungal strain Trichoderma viride EF-8 utilizing the abundant pigmented Egyptian onion (Allium cepa L.) skins (6.5%, w/v) was achieved in 4 days submerged fermentation (SMF) cultures, at temperature and pH of 30 °C and 4.0, respectively. The indigenously produced pectinase was partially purified by 50% batch ethanol precipitation and its general properties were studied following the standard procedures. The lyophilized enzyme preparation was free of any ochra or aflatoxins. The optimum conditions for the partially purified enzyme form were 2 mg/mL and 1% (w/v) enzyme protein and substrate (citrus pectin) concentrations, reaction pH and temperature of 7.0 and 40 °C, respectively. The results presented the low cost onion skins waste as the major substrate for the fungal pectinase production and its subsequent use in perfect fruit (apple, lemon and orange) juices clarification with remarkable stability during and after this process, which certainly enhance fruit juices processing in the tropics.

Quality Attributes of Cupuaçu Juice in Response to Treatment with Crude Enzyme Extract Produced by Aspergillus japonicus 586

Cupuaçu (Theobroma grandiflorum Schum) is an Amazonian Basin native fruit whose fruit pulp is consumed as a juice which presents high density, viscosity, and turbidity. Pectic enzymes, usually yielded by microorganisms, are used to reduce the juice viscosity and turbidity. The present study aims to evaluate the use of pectic enzymes when processing cupuaçu juice. The cupuaçu juice was obtained by using Aspergillus japonicus 586 crude enzyme extract and incubation at 50°C with agitation (140 rpm) for one hour. Enzyme activities were determined, and the juices were evaluated as to their yield, turbidity, viscosity, and chemical composition. The juice produced by using crude enzyme extract presented higher soluble solids, reducing sugars, and lower viscosity and turbidity.

Fungal multienzyme production on industrial by-products of the citrus-processing industry

Orange peels is the principal solid by-product of the citrus processing industry and the disposal of the fresh peels is becoming a major problem to many factories. Dry citrus peels are rich in pectin, cellulose and hemicellulose and may be used as a fermentation substrate. Production of multienzyme preparations containing pectinolytic, cellulolytic and xylanolytic enzymes by the mesophilic fungi Aspergillus niger BTL, Fusarium oxysporum F3, Neurospora crassa DSM 1129 and Penicillium decumbens under solid-state fermentation (SSF) on dry orange peels was enhanced by optimization of initial pH of the culture medium and initial moisture level. Under optimal conditions A. niger BTL was by far the most potent strain in polygalacturonase and pectate lyase, production followed by F. oxysporum F3, N. crassa DSM 1129 and P. decumbens. N. crassa DSM 1129 produced the highest endoglucanase activity and P. decumbens the lowest one. Comparison of xylanase production revealed that A. niger BTL produced the highest activity followed by N. crassa DSM 1129, P. decumbens and F. oxysporum F3. N. crassa DSM 1129 and P. decumbens did not produce any beta-xylosidase activity, while A. niger BTL produced approximately 10 times more beta-xylosidase than F. oxysporum F3. The highest invertase activity was produced by A. niger BTL while the lowest ones by F. oxysporum F3 and P. decumbens. After SSF of the four fungi, under optimal conditions, the fermented substrate was either directly exposed to autohydrolysis or new material was added, and the in situ produced multienzyme systems were successfully used for the partial degradation of orange peels polysaccharides and the liberation of fermentable sugars.

Degradation of mikan (Japanese mandarin orange) peel by a novel Penicillium species with cellulolytic and pectinolytic activity

AIMS

The mikan, or Japanese mandarin orange, is a popular fruit in Japan, but its peel is one of the major agricultural wastes. The aims of this study were to screen, isolate, and characterize a mikan peel-degrading microbe.

METHODS AND RESULTS

Several samples including activated sludge, sediment, compost and spoiled mikan peel were collected and cultured in a minimal salt medium containing mikan peel as the sole carbon source. Degradation activity was found in a culture of the spoiled mikan peel, and a fungal strain, designated OP1, with both cellulolytic and pectinolytic activity was isolated. No toxic metabolites, such as mycotoxins, were found in OP1 cultures, as evaluated by gas chromatography/mass spectrometry. A phylogenetic analysis strongly suggested that OP1 is a novel species of the genus Penicillium.

CONCLUSIONS

Results suggest that Penicillium sp. OP1 plays an important role in aerobic microbial degradation of cellulose/pectin-rich biomasses in soil ecology, and further imply that this strain may be useful for both simultaneous cellulase/pectinase production and reduction of agricultural waste.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present results advance our understanding of microbial degradation of cellulose/pectin-rich biomasses in the natural environment, and offer a new tool for reduction of agricultural waste, which is important for sustaining circulatory societies.