This fungus is often used as a biotechnological ingredient in pharmaceutical products. Its properties make it less harmful for humans. In fact, it is less likely to cause serious lung disease. This fungus is also used in the production of citric acid and as an insecticide.
Citric acid production
Aspergillus niger is a species of yeast used to produce citric acid. The species produces large amounts of iso-citric acid during the fermentation process. This species is responsible for the production of about 80% of citric acid in the world.
Aspergillus niger is an excellent choice for industrial synthesis of citric acid due to its high yields and easy handling. It can also ferment a wide range of inexpensive raw materials. In addition to its ease of use, the fungus has been extensively improved through mutagenesis. Using different mutagens, researchers have been able to induce mutations in A. niger to produce a better product.
Systematic metabolic engineering approaches and genome editing methods can be used to identify bottlenecks and optimize processes in A. niger. This approach could lead to more efficient production processes and reduce cost and environmental contamination. It can also reduce energy requirements. In addition, it can produce high levels of citric acid from low-cost sources, such as agro-industrial wastes and lignocellulose biomass.
Using a free-cell column bioreactor has been shown to enhance citric acid production. It also enhanced the cellulolytic activity of the fungus and enhanced the concentration of reducing sugars. After five days of fermentation, a concentration of reducing sugars increased two-fold.
Reusing agro-industrial wastewater can help reduce dependency on natural resources and reduce pollution. One method involves using the wastewater produced by olive mills to grow A. niger. It can produce approximately 25 grams of citric acid per liter. The production of this acid is enhanced when the cellulase enzymes are fed to the fungus continuously.
The glutamine synthase enzyme in Aspergillus niger is linked to pH, manganese, and ammonia. Keeping pH low during the production process reduces the risk of contamination, inhibits the formation of unwanted organic acids, and facilitates the recovery of the product. In addition, the structure of a particular enzyme depends on whether it has Mn2+ or Mg2+ ions.
Aspergillus niger can also produce citric acid from pulp of the fruit Parkia biglobosa. This is a cost-effective method that can generate a valuable organic acid.
Biotechnology
Aspergillus niger is one of the most widely used microorganisms in biotechnology. Its unique ability to secrete a diverse range of enzymes is exploited for biotransformations. These enzymes can be used in the food, pharmaceutical, and chemical industries.
The enzymes produced by this fungus are used in industrial fermentation and other applications. These enzymes include pectinases, which can be used to clarify cider and wine. Another enzyme produced by the fungus is alpha galactosidase, which breaks down complex sugars in foods, and is used in beano and other products to reduce flatulence.
Aspergillus niger has the ability to produce citric acid from molasses. It is a good candidate for biotechnology applications as it is both a fermentation organism and a pathogen. Its secretion machinery is effective and allows researchers to produce citric acid and other biochemicals.
Another important biotechnology application for this fungus is as a host for heterologous proteins. It can also serve as a cell factory for producing acids. It has the ability to grow on a wide variety of substrates and can degrade a variety of xenobiotics.
Its genome sequence is publicly available from JGI and DSM and will enable researchers to use it for various applications. This genome sequence will enable global proteomic analysis, as well as the development of fermentation processes and process development. It will also enable researchers to map genetic differences between wildtype and improved strains.
Several important research areas have been focused on A. niger, including eukaryotic protein secretion, various biomass degrading enzymes, and metabolic control. Currently, the organism is used as a model organism for various types of fermentation processes.
Postharvest disease of onions
Postharvest disease of onions is a common problem for growers in many temperate regions. It can cause severe losses if not treated and can be prevented by following proper curing procedures. To prevent infection, it is important to choose resistant cultivars and use a fungicide.
The disease occurs when the fungus grows in a warm, moist environment. It prefers high temperatures, with the most rapid growth occurring at 35degC, while the slowest growth occurs at thirteendegC. Onions grown in New Mexico should be protected from moisture during their growing and harvesting processes. Prompt curing and proper ventilation are also recommended to prevent the growth of black mold.
The fungus Aspergillus niger is a plant pathogen that causes postharvest disease in onions. It also causes rot in other crops, such as peanuts, grapes, and tomatoes. It can also be found in compost piles and stored grain.
Onions can be infected with Aspergillus niger through the introduction of its spores by termites and mites. Aspergillus niger is best controlled by protecting the bulbs from excessive moisture during the growing and storage process.
The disease is usually not fatal for the plant, but it reduces the bulb size and seed yield. It weakens the plant and makes it more susceptible to other diseases, pests, and environmental stresses. The plants can be more susceptible to the disease if they are subjected to high environmental and cultural stress, and the symptoms will be more severe.
Inoculum is transported from bulb to bulb on tractors and tillage implements. Therefore, clippers used for onion cultivation should be disinfected frequently. They should also be kept in a dry area with good ventilation. The bulbs should be stored at 32degF or slightly higher.
Fumigation is another postharvest disease prevention technique. It is used in a variety of agricultural settings and has been shown to reduce the incidence of postharvest disease of onions. The fumigant is applied by heating a thymol powder and applying it to the onions. This method is effective against the predominant fungal pathogen B. aclada.
CRISPR-Cas9 gene editing technology
CRISPR-Cas9 gene-editing technology has been successfully applied to the gene-editing process of Aspergillus niger, a mold. The gene-editing technology allows scientists to create mutants with altered phenotypes through a simple process. After transient transfection of plasmids into Aspergillus niger, the transformants are screened phenotypically and are confirmed to have the desired phenotype.
The CRISPR-Cas9 system is a powerful and versatile tool for genome editing. It is already being used for gene-editing in filamentous fungi. However, the major challenge in CRISPR mutagenesis in Aspergillus species is the delivery of guide RNA (gRNA). To overcome this limitation, researchers used a plasmid with cas9 and gRNA expressed in one single copy. This allowed scientists to achieve a 97% efficiency rate for CRISPR mutagenesis in A. niger.
The CRISPR-Cas9 system is a bacterial genome editing technology that can insert and delete genes. This technology utilizes donor DNA to correct DNA breaks and alter the genome. It has been used successfully for plant and yeast genome editing.
The first step of the CRISPR-Cas9 gene-editing process in Aspergillus niger was to isolate a single mutant colony from the original transformants. This was accomplished by dilution of the primary transformants to 104-105 times. After streaking the transformants on hygromycin for three days, DNA was extracted. The sequenced DNA was analyzed for mutations in the upstream PAM motif.
The next step involved determining the mutant. To do so, researchers obtained colonies of A. niger that had hygromycin resistance. They also performed PCR tests to determine whether the insertion fragment is present in the genome. The results indicated that three out of five positive transformants carry the insertion fragment. After further PCR analysis, one of these three candidates was selected as the agdF-glaA mutant. The mutant had a 25.9% higher glucoamylase activity than the wild strain and 61.4% less a-glucosidase activity than the wild strain.