Part of the book: Fungicides for Plant and Animal Diseases
Fructooligosaccharides (FOS) are considered prebiotic compounds and are found in different vegetables and fruits but at low concentrations. FOS are produced by enzymatic transformation of sucrose using fructosyltransferase (FTase). Development of new production methods and search for FTase with high activity and stability for FOS production Is an actual research topic. In this article is discussed the most recent advances on FTase and its applications. Different microorganisms have been tested under various fermentation systems in order to identify and characterize new genes codifying for FTase. Some of these genes have been isolated from bacteria, fungi, and plants, with a wide range of percentages of identity but retaining the eight highly conserved motifs of the hydrolase family 32 glycoside. Therefore, this article presents an overview of the most recent advances on FTase and its applications.
Part of the book: Probiotics and Prebiotics in Human Nutrition and Health
The solid-state fermentation (SSF) is the best option to produce spores of biological control agents (BCA), because the spores have a long shelf life, compared with the obtained in liquid cultures. The spore production under SSF conditions using polyethylene bioreactors (bag-type) is a new topic. Only little information mainly about bioreactors design and adequate conditions to spore production is available. The main aim of this study was to use the corn cob as substrate in SSF and produce spores of the fungi BCA Trichoderma asperellum in a polyethylene bioreactor. In the process was added biomass of the phytopathogenic fungi Colletotrichum gloeosporioides and Phytophthora capsici as inducers of hydrolase enzymes (endoglucanases, exoglucanases and chitinases). It is possible to obtain high levels of spores, cellulases and chitinases using a polyethylene bioreactor under SSF conditions by T. asperellum and corn cob as substrate. Under the SSF conditions evaluated, the biomass of C. gloeosporioides has an inducer effect just on the spore production. However, P. capsici have effect on all response variables evaluated. The spore production was twice when used P. capsici as inducer. The most influential factor under SSF was the moisture. Levels of 66 and 50% of this factor increase the yield in all response variables evaluated (sporulation, cellulases and chitinases), C. gloeosporioides and P. capsici, respectively.
Part of the book: Fermentation Processes
Polyembryony (PE) is a rare phenomenon in cultivated plant species. Since nineteenth century, several reports have been published on PE in maize. Reports of multiple seedlings developing at embryonic level in laboratory and studies under greenhouse and field conditions have demonstrated the presence of PE in cultivated maize (Zea mays L.). Nevertheless, there is a lack of knowledge about this phenomenon; diverse genetic mechanisms controlling PE in maize have been proposed: Mendelian inheritance of a single gene, interaction between two genes and multiple genes are some of the proposed mechanisms. On the other hand, the presence of two or more embryos per seed confers higher nutrimental quality because these grains have more crude fat and lysine than normal maize kernels. As mentioned above, there is a necessity for more studies about PE maize in order to establish the genetic mechanism responsible for this phenomenon; on the other hand, previous studies showed that PE has potential to generate specialized maize varieties with yield potential and grain quality.
Part of the book: Maize Germplasm