Solanum tuberosum (Potato) is one of the essential economic crops with the potential to reduce hunger due to its high yield per unit area of land compared with many economic crops. However, its yield losses due to pest and disease attacks could be as high as 100%, depending on its tolerance level and pest and disease. Over the years, several disease management strategies have been researched, ranging from synthetic pesticides to the formulation of biopesticides as disease control measures. Moreso, recent breakthroughs in genetic engineering have simplified plant disease management strategies by developing techniques for conferring resistance on plants. Potato is a vital food crop worldwide, and with the struggle to suppress world food insecurity, effective disease management strategies must be employed for high production of quality and quantity potato, enough to feed the ever-increasing world population. Therefore, attention must be given to how disease-free potatoes can be produced to meet the unending demand for food by the continually increasing world population.

Pectinases, like other industrial enzymes are usually expensive. The use of pineapple peel pectin as substrate is triggered by the large tones of pineapple waste generated in Nigeria. Oil extraction by mechanical/chemical means have associated disadvantages. This research aimed at employing locally produced pectinase for coconut-oil extraction and to compare the yield with commercial pectinase. Fifty grammes of dried pineapple peel powder were employed for pectin production. Aspergillus niger isolated from cassava meal was employed to produce pectinase using submerged fermentation for seven days. The activity of pectinase was determined at 24 h interval. The pectinase was partially purified using 3% activated carbon, characterized and employed to extract oil from coconut. The yield of pectin from the pineapple peels was 24.8% after 1 h of extraction time. Highest pectinase activity was observed on day five. Optimum conditions were 40°C, 5.0 and 1% respectively for temperature, pH and substrate concentration. The enzyme was completely inactive after 5 min of heating at 90°C and metal ion (Mg2+) stimulated its activity. The mean oil yield from the locally produced pectinase was greater than the commercial pectinase. The pectinase produced from this study enhanced coconut-oil extraction when compared with the mechanical method.

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Tannase (Tannin acyl hydrolase, EC 3.1.1.20) is an enzyme produced in the presence of tannic acid by various filamentous fungi. They are produced principally by fungi of the genus Aspergillus and Penicillium. The enzyme is used in the food and beverage industry as a clarifying agent for wines, beers and fruit juices. In Africa, billions of dollars are expended yearly on the importation of commercial enzymes for the food and pharmaceutical industries and this increases the cost of production and the finished goods. This study was carried out to isolate tannase producing fungal species using Bambara nuts as a substrate in a bid to finding alternatives to the importation of tannase. Fresh Bambara nuts were collected from different locations in Nigeria. They were cleaned, sorted and intermittently moistened with water to encourage fungal growth for fourteen days. The different fungi obtained after fourteen days were inoculated onto Potato Dextrose Agar plates and incubated at 25°C for five days. Subculturing of fungal isolates was carried out to obtain pure cultures of isolates. Tannilytic activity (hydrolysis of tannin) of isolates was assessed by inoculating them in media containing tannin. The plates were incubated at 25°C for 2-5 days after which the plates were observed and zones of hydrolysis measured. A total of eighteen isolates were obtained. They were all members of the Aspergillus genus. 56% (10) of the isolates were able to degrade tannin acid with mean zone of hydrolysis of 39mm ±23.7 mm (Range 10-70mm). This study established members of the Aspergillus genus isolated from Bambara nuts as viable fungi for application in the production of tannase. This study adds to existing reports on fungal production of tannase.