China 
Africa 
Explore chapters and articles related to this topic
Principles of Chemistry
Published in Arthur T. Johnson, Biology for Engineers, 2019
Enzymes are characterized by their actions. There are enzymes that link two compounds together (called ligases), enzymes that transfer a chemical group from one compound to another (transferases), enzymes that catalyze hydrolysis (hydrolases), enzymes that remove a chemical group from substrates (lyases), enzymes that oxidize some compounds while reducing others (oxidoreductases), and enzymes that convert one isomer to another (isomerases). In general, there is an enzyme for every chemical reaction important to living systems. Some enzymes are very specific, yet others may have several functions. For instance, the enzyme maltase is specific to the sugar maltose and produces glucose as a result of its action. Chymotrypsin, on the other hand, is a general enzyme for the digestion of proteins, and can operate on many proteins.
Biodegradation of Starch
Published in Jean-Luc Wertz, Bénédicte Goffin, Starch in the Bioeconomy, 2020
Jean-Luc Wertz, Bénédicte Goffin
The pathway by which starch is converted to glucose in the endosperm of germinating cereal seeds is relatively simple (Figure 4.17).44 The starch granule is attacked by the endoamylase AMY. AMY releases both linear and branched oligosaccharides from the starch granule. These soluble products are then acted upon by two further enzymes. LDA, a debranching enzyme, generates linear chains by cleaving the α-1,6 linkages. The exoamylase BAM releases the disaccharide maltose. Maltose is hydrolyzed to two glucose molecules by an α-glucosidase (also known as maltase). All these enzymes are classified as glycoside hydrolases.
High yield production of lipid and carotenoids in a newly isolated Rhodotorula mucilaginosa by adapting process optimization approach
Published in Biofuels, 2023
Ravi Gedela, Ashish Prabhu, Venkata Dasu Veeranki, Pakshirajan Kannan
The molasses is a by-product of the sugarcane industry with approximately 30% (w/v) of sucrose have shown lipid production of 42.23% (w/w), which is less as compared with the pure sucrose (46.06%), however the production of carotenoid is approximately equal for both the substrates (Figure 2(B)). Previously, Karatay et al. [4] used molasses and ammonium sulfate as carbon and nitrogen source, respectively for the production of lipids in oleaginous yeast and reported lipid content of 59.9, 46.8 and 69.5% for C. lipolytica, C. tropicalis and R. mucilaginosa, respectively. On supplementation of maltose, the organism displayed 47.14% (w/w) lipid production that is equivalent to the lipid accumulation with glucose but the carotenoid production is quite less as compared with glucose fermentation. As the maltose is composed of two monomers of glucose, the cleavage of the glycosidic linkages by the maltase enzyme has released more glucose in the medium and the simultaneous consumption led to increase in biomass and lipid content in R. mucilaginous.
Reuse of wheat flour liquid waste for enzymatic hydrolysis to yield glucose-derived bioethanol
Published in Cogent Engineering, 2022
N.K. Sari, I.Y. Purbasari, P.W. Anggoro, J. Jamari, A.P. Bayuseno
SRM also evaluated the effect of ME on glucose production at different volumes of WF-LW. The result can be predicted from the equations of (Sari & Dira, 2018) and (Dubey et al., 2012), which stated that the maximum glucose production was achieved at a value higher than 21% v/v. Furthermore, the linear effect of ME and type of WF-LW was also observed. The maltase factor linearly affected the yields of glucose levels. Any change in WF-LW volume, either decreasing or increasing from the lower target of maltose concentration, increased glucose production, as shown in Figures 8 and 9. The results showed that ME ranging from 3.0% to 15.0% w/v gradually increased glucose production from volumes of WF-LW 200 to 600 mL with a maximum of 651.426 mL (Table 3). Moreover, the optimal response parameter of ME (7.37151% w/v) and WF-LW volume (651.426 mL) significantly yielded glucose levels of 21.34% v/v. The desirability function, namely 0.624970 of the SRM approach, suggested that ME had a less significant effect on glucose production (Table 3, Table 4). The optimal yield response of 24.9% v/v for the fermented ME was noted in this study.
Anaerobic acidification of sugar-containing wastewater for biotechnological production of organic acids and ethanol
Published in Environmental Technology, 2019
Wipa Charles, Ralf Cord-Ruwisch
Change of the HRT from 4 to 2 days under pH control of 7 caused the anaerobic acidification of maltose to stop while fermented glucose changed from the production of acetate to ethanol as the main end-product (Figure 4). This result reaffirmed the previous test on anaerobic acidification of sugars under pH control of 6 showing that HRT 2 day was not feasible or somewhat too short for microbes to excrete maltase optimally for hydrolyzing maltose into glucose to form end-products. This occurred as a short HRT was the condition favoured by the acid-forming bacteria to grow and form organic acids [2,44]. Hence, the short HRT could be an inhibition factor for converting maltose into glucose. This was due to the fact that the 2 days of HRT was short enough that could lead to wash-out, and/or slow down the growth of microbes. Subsequently, the production of bio-products from fermented maltose was impossible to occur at this short HRT.