Related Experiment Video
Updated: Jul 5, 2026
09:27
Immobilization of Multi-biocatalysts in Alginate Beads for Cofactor Regeneration and Improved Reusability
Published on: April 22, 2016
Xylanase production by Bacillus circulans D1 using maltose as carbon source
D A Bocchini1, E Gomes, R Da Silva
1Laboratório de Bioquímica e Microbiologia Aplicada, IBILCE-Instituto de Biociências Letras e Ciências Exatas, UNESP-Universidade Estadual Paulista, São José do Rio Preto, São Paulo, Brazil.
Applied Biochemistry and Biotechnology
|April 19, 2008
Summary
Bacillus circulans D1 efficiently produces thermostable xylanase, with D-maltose as the optimal carbon source for enzyme synthesis. Glucose and xylose significantly repressed xylanase production, highlighting the importance of carbon source selection for enzyme yield.
Area of Science:
- Biotechnology
- Enzyme Engineering
- Microbial Physiology
Background:
- Extracellular thermostable xylanase production by Bacillus circulans D1 was investigated.
- Understanding enzyme induction and repression is crucial for optimizing microbial fermentation processes.
Purpose of the Study:
- To evaluate xylanase production by Bacillus circulans D1 using various carbon sources.
- To determine the optimal carbon source for maximizing enzyme synthesis and understand the effects of different sugars on xylanase production.
Main Methods:
- Cultivation of Bacillus circulans D1 in media supplemented with different carbon sources (D-maltose, D-glucose, D-arabinose, D-cellobiose, oat spelt xylan).
- Quantification of extracellular thermostable xylanase activity.
- Assessment of cellulase activity in the crude enzyme solution.
- Evaluation of the effects of glucose and xylose supplementation on xylanase production in xylan and maltose media.
Main Results:
- D-maltose was identified as the best inducer for xylanase synthesis, yielding 7.05 U/mg dry biomass at 48 h.
- D-glucose and D-arabinose resulted in basal levels of xylanase production.
- The crude enzyme solution was free of cellulases, even when cultivated with D-cellobiose.
- Glucose and xylose exhibited significant repressive effects on xylanase production in oat spelt xylan medium.
- Glucose repressed xylanase production in maltose medium, while xylose at low concentrations induced it, showing varied repressive effects at higher concentrations compared to xylan medium.
Conclusions:
- D-maltose is the most effective carbon source for inducing high levels of extracellular thermostable xylanase production by Bacillus circulans D1.
- Carbon source availability significantly influences xylanase gene expression, with glucose and xylose generally acting as repressors, though their effect varies depending on the primary substrate.
- Bacillus circulans D1 is a promising candidate for industrial xylanase production due to its high yield and the absence of cellulase contamination.
Related Concept Videos
01:25Production of Organic Acids
Lactic acid, an important organic acid extensively applied in food, pharmaceutical, and biodegradable polymer industries, is primarily produced via microbial fermentation. This method is favored over chemical synthesis due to its environmental sustainability and capacity for enantiomerically pure product formation. Among various microbial processes, the fermentation of starch-based substrates stands out due to the abundance and renewability of raw materials like corn and potatoes.Hydrolysis of...
01:27Production of Alcohol
Continuous fermentation is a key strategy in industrial ethanol production, particularly when efficiency, scalability, and high yields are essential. This approach allows for uninterrupted operation and optimized resource utilization. The primary feedstock, corn starch, undergoes enzymatic hydrolysis facilitated by α-amylase and glucoamylase. These enzymes break down the starch into fermentable sugars such as glucose, which are readily assimilated by fermentative microorganisms.Fermentation...
01:27Production of Antibiotics
Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
01:29Microbes in Food Production
Microbial fermentation is central to food biotechnology, enhancing flavor, texture, preservation, and stability. Fermentative microorganisms metabolize carbohydrates into organic acids, alcohols, and other metabolites that inhibit spoilage organisms and improve digestibility while contributing distinctive sensory qualities.In baking, amylases naturally present in flour hydrolyze starch into monosaccharides such as glucose, which Saccharomyces cerevisiae ferments anaerobically. Through...