Loading...
4 results
Search Results
Now showing 1 - 4 of 4
- Recent advances in β-galactosidase and fructosyltransferase immobilization technologyPublication . Ureta, Maria Micaela; Martins, Gonçalo Nuno; Figueira, Onofre; Pires, Pedro Filipe; Castilho, Paula Cristina; Gomez-Zavaglia, AndreaThe highly demanding conditions of industrial processes may lower the stability and affect the activity of enzymes used as biocatalysts. Enzyme immobilization emerged as an approach to pro mote stabilization and easy removal of enzymes for their reusability. The aim of this review is to go through the principal immobilization strategies addressed to achieve optimal industrial proc esses with special care on those reported for two types of enzymes: b-galactosidases and fructo syltransferases. The main methods used to immobilize these two enzymes are adsorption, entrapment, covalent coupling and cross-linking or aggregation (no support is used), all of them having pros and cons. Regarding the support, it should be cost-effective, assure the reusability and an easy recovery of the enzyme, increasing its stability and durability. The discussion provided showed that the type of enzyme, its origin, its purity, together with the type of immobilization method and the support will affect the performance during the enzymatic synthesis. Enzymes’ immobilization involves interdisciplinary knowledge including enzymology, nanotechnology, molecular dynamics, cellular physiology and process design. The increasing availability of facilities has opened a variety of possibilities to define strategies to optimize the activity and re-usability of b-galactosidases and fructosyltransferases, but there is still great place for innovative developments.
- Chickpeas’ and Lentils’ Soaking and Cooking Wastewaters Repurposed for Growing Lactic Acid BacteriaPublication . Martins, Gonçalo Nuno; Carboni, Angela Daniela; Hugo, Ayelén Amelia; Castilho, Paula Cristina; Gómez-Zavaglia, AndreaLegumes processing involves large amounts of water to remove anti-nutrients, reduce uncomfortable effects, and improve organoleptic characteristics. This procedure generates waste and high levels of environmental pollution. This work aims to evaluate the galacto-oligosaccharide (GOS) and general carbohydrate composition of legume wastewaters and assess their potential for growing lactic acid bacteria. Legume wastewater extracts were produced by soaking and/or cooking the dry seeds of chickpeas and lentils in distilled water and analysed using high-performance liquid chromatography with refractive index detection. GOS were present in all extracts, which was also confirmed by Fourier transform infrared spectroscopy (FTIR). C-BW extract, produced by cooking chickpeas without soaking, provided the highest extraction yield of 3% (g/100 g dry seeds). Lentil extracts were the richest source of GOS with degree of polymerization ≥ 5 (0.4%). Lactiplantibacillus plantarum CIDCA 83114 was able to grow in de Man, Rogosa, and Sharpe (MRS) broth prepared by replacing the glucose naturally present in the medium with chickpeas’ and lentils’ extracts. Bacteria were able to consume the mono and disaccharides present in the media with extracts, as demonstrated by HPLC and FTIR. These results provide support for the revalorisation of chickpeas’ and lentils’ wastewater, being also a sustainable way to purify GOS by removing mono and disaccharides from the mixtures.
- Lactic Acid Bacteria in the Production of Traditional Fermented Foods and Beverages of Latin AmericaPublication . Carboni, Angela; Martins, Gonçalo N.; Gomez-Zavaglia, Andrea; Castilho, Paula C.Traditional fermented foods are inherent to the human diet and represent an important part of the culture of each country. The fermentation process has been traditionally used as a method of food preservation. It allows modifying the technological, sensory, and nutritional attributes of raw ingredients. Latin America has a vast history with these products, but they are not always known worldwide. One of the most used microorganisms in fermented foods is lactic acid bacteria. This review aims to provide insight into the main attributes, benefits, and nutritional characteristics of traditional fermented foods and beverages from Latin America made with lactic acid bacteria. A bibliography analysis of the general aspects of fermented products from this region was carried out, focusing on the foods and beverages (with and without alcohol), their representation in native communities, nutritional value and effect on health, as well as the risk of their consumption. It is concluded that traditional fermented products of Latin America are usually prepared with specific ingredients of the region (such as cassava and corn), and that the lactic acid bacteria present in these foods are not always identifiable due to the inherent variability of artisanal production. The bacteria observed include Lacticaseibacillus, Lactiplantibacillus, Lactobacillus, Limosilactobacillus, Leuconostoc, Streptococcus, and Weisella, among others.
- Technological aspects of the production of fructo and Galacto-Oligosaccharides. Enzymatic Synthesis and HydrolysisPublication . Martins, Gonçalo N.; Ureta, Maria Micaela; Tymczyszyn, E. Elizabeth; Castilho, Paula C.; Gomez-Zavaglia, AndreaFructo- and galacto-oligosaccharides (FOS and GOS) are non-digestible oligosaccharides with prebiotic properties that can be incorporated into a wide number of products. This review details the general outlines for the production of FOS and GOS, both by enzymatic synthesis using disaccharides or other substrates, and by hydrolysis of polysaccharides. Special emphasis is laid on technological aspects, raw materials, properties, and applications.