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Microbial Valorization of Food Industry Wastes for Production of Nutraceutical Molecules
Published in Jitendra Kumar Saini, Surender Singh, Lata Nain, Sustainable Microbial Technologies for Valorization of Agro-Industrial Wastes, 2023
K. Ranjitha, Vijay Rakesh Reddy, Harinder Singh Oberoi
Galactooligosaccharides (GOS) are important prebiotics synthesized conventionally from lactose by a special enzyme called β-galactosidase (EC 3.2.1.23). β-galactosidases are very commonly produced enzymes across microbial groups. This enzyme hydrolytically splits the lactose as well as catalyzes transgalactosylation to produce galactooligosaccharides (Prenosil et al., 1987). Instead of using pure enzymes, GOS production through microbial cell factories is explored. Recently, GOS production from dairy effluents using mixed cultures of Bacillus singularis and Saccharomyces sp. was patented in the USA (US9139856B2—process for the production of galactooligosaccharides [GOS], Google Patents). The system is claimed to have more economic advantage by making possible the repeated use of cell biomass and by obtaining pure GOS without interference from galactose.
β-galactosidase Using Gel-Filtration Chromatography
Published in Maik W. Jornitz, Filtration and Purification in the Biopharmaceutical Industry, 2019
The enzyme has three activities that ultimately result in the complete breakdown of the disaccharide lactose into galactose plus glucose. First, β-galactosidase cleaves lactose into galactose plus glucose. Second, the enzyme acts as a transglycosylase, converting lactose into allolactose. Third, it hydrolyzes allolactose into galactose plus glucose. Historically, it has been a puzzle as to why the β-galactosidase protein is so large and why it needs to be a tetramer. The recent elucidation of this enzyme’s multiple and sequential activities may help explain its structural complexity and large mass.6
Proteins and Proteomics
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2020
Escherichia coli synthesis of β-galactosidase has been extensively studied in which lactose is converted into glucose and galactose. To understand the synthesis of β-galactosidase in E. coli, experiments were performed, and it was observed that if β-galactosides are not supplied to E. coli cells, the presence of β-galactosidase is hardly detectable but as soon as lactose is added, production of the enzyme β-galactosidase increases as much as 10,000 times. The enzyme quantity again falls as quickly as the substrate (lactose) is removed. Such enzymes whose synthesis can be induced by adding a substrate are known as inducible enzymes and the genetic systems responsible for the synthesis of such enzymes are known as inducible systems. In another situation where no amino acids are supplied from outside, E. coli cells can synthesize all the enzymes needed for the synthesis of different amino acids. However, if an amino acid like histidine is added, the production of histidine-synthesized enzymes declines. In such a scenario, the addition of an end product of a biosynthetic pathway will check synthesis of the enzymes needed for its biosynthesis. The enzymes whose synthesis can be repressed by adding an end product are known as repressible enzymes and their genetic systems are known as repressible systems. The substrate whose addition induced the synthesis of an enzyme (as lactose in the case of synthesis of β-galactosidase) is called an inducer. In the same way, the end product whose addition repressed the synthesis of biosynthetic enzymes is called a co-repressor. Note that in the absence of lactose, no β-galactosidase is synthesized. This would mean that in the absence of an inducer, the gene or genes responsible for the synthesis of β-galactosidase do not function.
Production, purification, characterization, and applications of α-galactosidase from Bacillus flexus JS27 isolated from Manikaran hot springs
Published in Preparative Biochemistry & Biotechnology, 2023
Sonu Bhatia, Navneet Batra, Jagtar Singh
α-Galactosidase has been isolated and characterized from the microbial, plant, and animal sources. Bacterial sources include Bacteroides ovatus, Bifidobacterium breve, Lactobacillus acidophilus, Pontibacter sp., Streptococcus pneumoniae, etc., while, Aspergillus niger, Aspergillus satoi, Candida albicans, Penicillium chrysogenum, etc. are significant fungal sources. The enzyme has also been isolated from plants including Ceretonia siliqua, Cicer arietinum, Coffea arabica, Nicotiana tabacum, Vicia faba whereas humans, pigs, rats, rabbit, etc. are major animal sources.[2,3] Most commercialized microorganisms include strains of Lactobacillus and Aspergillus.
Bio-conversion of whey lactose using enzymatic hydrolysis with β-galactosidase: an experimental and kinetic study
Published in Environmental Technology, 2022
K. Bella, Sridhar Pilli, P. Venkateswara Rao, R. D. Tyagi
The enzyme β-Galactosidase having animal, plant and microbial (yeast, fungi and bacteria) origin, is highly productive in microbial forms. Enzymes derived from fungi (Aspergillus niger and Aspergillus oryzae) and yeasts (Kluyveromyces fragilis and Kluyveromyces lactis) show high commercial potential. However, the activity of these enzymes is greatly affected by pH, temperature, pressure, the concentration of reactants and the presence of metal ions. When optimal operating conditions are developed for an enzyme, enzyme wastage can be reduced, resulting in higher hydrolysis rates and shorter hydrolysis times. Multiple parameter optimisation can be carried out with Response Surface Methodology (RSM) by analysing the combined effect of all parameters on a particular response [23]. The Central Composite Design (CCD) is the standard method chosen in RSM by many researchers [24, 25].
Potential of “coalho” cheese whey as lactose source for β-galactosidase and ethanol co-production by Kluyveromyces spp. yeasts
Published in Preparative Biochemistry & Biotechnology, 2020
Catherine Teixeira de Carvalho, Sérgio Dantas de Oliveira Júnior, Wildson Bernardino de Brito Lima, Fábio Gonçalves Macêdo de Medeiros, Ana Laura Oliveira de Sá Leitão, Everaldo Silvino dos Santos, Gorete Ribeiro de Macedo, Francisco Caninde de Sousa Júnior
Several strategies have been investigated for dealing with the CW waste disposal and the use of biotechnological processes figures as an interesting way of converting such by-product into a valuable feedstock.[8] Although difficult to degrade on the environment, the lactose content of CW can be used as a platform for the fermentation of value-added products such as ethanol, galactonic acid, [9] and β-galactosidase.[10] The enzyme β-galactosidase (β-gal; EC 3.2.1.23), also known as lactase, is a product of great interest and several applications in the food industry, as it is responsible for the hydrolysis of lactose glycosidic bonds.[11] In addition, to the increasing market share of lactose-free products for diet-restricted consumers,[12] β-gal is also used for the enzymatic production of food prebiotics such as lactulose and different galacto-oligosaccharides (GOS).[11,13]