Properties of polylactide, obtained
from lactic acid in the process of lactic
fermentation of lactose in whey post
production (waste)

Purpose: This publication provides a description of RDC Glokor’s own research into the effectiveness of the lactic fermentation process of lactose, lactic acid concentration and polylactide (PLA) production by ring-opening polymerization obtained from the condensation of two molecules of lactic acid. Furthermore, this publication sets out to determine potential applications of the PLA as a commercial material with a selection of thermal properties. Design/methodology/approach: In the described research works, a lactic fermentation process was used in which lactose is converted to lactic acid with the participation of Lactic Acid Bacteria. Polylactide was obtained indirectly by Ring Opening Polymerization and by direct polymerization, straight from lactic acid, omitting the intermediate stages. Next, the obtained lactide and polylactide were examined by spectroscopic methods (IR, NMR) to determine their purity. Thermal methods (TG, DSC) to determine thermoplastic properties, i.e. softening point, decomposition temperature and glass transition temperature. Findings: Obtained from waste whey, PLA and its copolymers are excellent biodegradable polymers that have the potential to be used in medicine as resorbable surgical strands, biopolymers for implant production, as well as in many industries including for the production of biodegradable bottles and disposable packaging, 3D printer cartridges. Research limitations/implications: The research on lactic acid and lactide polymerization described in this article is still a new issue that requires further research to optimize PLA processes with industry-specific thermoplastic and physicochemical properties. Originality/value: In the basic waste processing of milk, there is a large volume of whey sour, which is ecologically dangerous for waste treating. Due to the high content of lactose (up to 6%) this waste can be used as a raw material in the lactic fermentation process in which lactose is converted to lactic acid with the participation of lactic acid bacteria. Lactic acid can be concentrated and subjected to a dehydration process to lactide, which in the final stage is subjected to the process of ring-opening polymerization in order to produce biodegradable polylactide. The described process of carrying out the lactose contained in PLA whey is an innovative way to obtain a biodegradable usable polymer, which can be used to replace plastics such as polypropylene and polyethylene.

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Bacterias del Ácido Láctico un Potencial para la Producción de Alimentos Probióticos Fermentados en la Industria Láctea de Panamá

KnE Engineering ◽

10.18502/keg.v3i1.1411 ◽

2018 ◽

Vol 3 (1) ◽

pp. 38

Author(s):

Por: Melvys Jacqueline Vega Quintero

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Milk Production ◽

Fermentation Process ◽

Biological Diversity ◽

Bacterial Species ◽

Fermented Milk ◽

Lactic Fermentation ◽

Continue Research ◽

High Production

The lactic acid bacteria known by their initials (BAL) are microorganisms that in the absence of oxygen degrade carbohydrates like lactose (milk sugar), to synthesize lactic acid and energy, through a process known as lactic fermentation. In the dairy industry these microorganisms are used as lactic ferments or initiators of the lactic fermentation process for the manufacture of cheeses, yogurt, fermented milk and other products derived from milk. The type of bacterial species used as an initiator in the fermentation process is a determining factor in the nutritional quality and sensorial characteristics of the final product. The main objective of the investigation is to carry out an evaluation on the potential of sources and milk production in Panama, specifically in the Chiriquí Highlands. Regarding the scope of the research, its perspective is to continue research on the biological diversity of lactic acid bacteria present in dairy sources, for their isolation and use in the dairy industries. It is important to highlight the high production of cattle, sources and milk production in the Highlands, which represents a potential diversity of lactic acid bacteria.Keywords: Lactic acid bacteria, lactic fermentation, probiotic foods, genetic markers, phenotype.

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Controlled ring-opening polymerization of lactide by group 3 metal complexes

Pure and Applied Chemistry ◽

10.1351/pac200779112013 ◽

2007 ◽

Vol 79 (11) ◽

pp. 2013-2030 ◽

Cited By ~ 112

Author(s):

Abderramane Amgoune ◽

Christophe M. Thomas ◽

Jean-François Carpentier

Keyword(s):

Lactic Acid ◽

Metal Complexes ◽

Ring Opening ◽

Ring Opening Polymerization ◽

Agricultural Fields ◽

Research Results ◽

Potential Applications ◽

Group 3 ◽

Biodegradable Properties

In this review, attention is focused on the use of group 3 metal complexes for the ring-opening polymerization (ROP) of lactide to give polylactides (PLAs). Synthesis of PLAs has been studied intensively due to their biocompatible and biodegradable properties and their potential applications in medical and agricultural fields. ROP of lactide, a cyclic diester of lactic acid, provides PLA. This review includes our recent research results and implications in developing new amino-bis(phenolate) group 3 initiators for the synthesis of polyesters.

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Brewers’ spent grain as substrate for dextran biosynthesis by Leuconostoc pseudomesenteroides DSM20193 and Weissella confusa A16

Microbial Cell Factories ◽

10.1186/s12934-021-01515-4 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Prabin Koirala ◽

Ndegwa Henry Maina ◽

Hanna Nihtilä ◽

Kati Katina ◽

Rossana Coda

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Raw Materials ◽

Degree Of Polymerization ◽

Raw Material ◽

Fermentation Time ◽

Viscosity Increase ◽

Spent Grain ◽

Leuconostoc Pseudomesenteroides ◽

Weissella Confusa

Abstract Background Lactic acid bacteria can synthesize dextran and oligosaccharides with different functionality, depending on the strain and fermentation conditions. As natural structure-forming agent, dextran has proven useful as food additive, improving the properties of several raw materials with poor technological quality, such as cereal by-products, fiber-and protein-rich matrices, enabling their use in food applications. In this study, we assessed dextran biosynthesis in situ during fermentation of brewers´ spent grain (BSG), the main by-product of beer brewing industry, with Leuconostoc pseudomesenteroides DSM20193 and Weissella confusa A16. The starters performance and the primary metabolites formed during 24 h of fermentation with and without 4% sucrose (w/w) were followed. Results The starters showed similar growth and acidification kinetics, but different sugar utilization, especially in presence of sucrose. Viscosity increase in fermented BSG containing sucrose occurred first after 10 h, and it kept increasing until 24 h concomitantly with dextran formation. Dextran content after 24 h was approximately 1% on the total weight of the BSG. Oligosaccharides with different degree of polymerization were formed together with dextran from 10 to 24 h. Three dextransucrase genes were identified in L. pseudomesenteroides DSM20193, one of which was significantly upregulated and remained active throughout the fermentation time. One dextransucrase gene was identified in W. confusa A16 also showing a typical induction profile, with highest upregulation at 10 h. Conclusions Selected lactic acid bacteria starters produced significant amount of dextran in brewers’ spent grain while forming oligosaccharides with different degree of polymerization. Putative dextransucrase genes identified in the starters showed a typical induction profile. Formation of dextran and oligosaccharides in BSG during lactic acid bacteria fermentation can be tailored to achieve specific technological properties of this raw material, contributing to its reintegration into the food chain.

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Different lactic acid bacteria and their combinations regulated the fermentation process of ensiled alfalfa: ensiling characteristics, dynamics of bacterial community and their functional shifts

Microbial Biotechnology ◽

10.1111/1751-7915.13785 ◽

2021 ◽

Author(s):

Jie Bai ◽

Zitong Ding ◽

Wencan Ke ◽

Dongmei Xu ◽

Museng Wang ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacterial Community ◽

Fermentation Process

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Co-Microencapsulated Black Rice Anthocyanins and Lactic Acid Bacteria: Evidence on Powders Profile and In Vitro Digestion

Molecules ◽

10.3390/molecules26092579 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2579

Author(s):

Carmen-Alina Bolea ◽

Mihaela Cotârleț ◽

Elena Enachi ◽

Vasilica Barbu ◽

Nicoleta Stănciuc

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Oryza Sativa L ◽

Milk Proteins ◽

Ethanolic Extract ◽

Dry Weight ◽

Hot Water ◽

Raw Material ◽

Black Rice

Two multi-functional powders, in terms of anthocyanins from black rice (Oryza sativa L.) and lactic acid bacteria (Lactobacillus paracasei, L. casei 431®) were obtained through co-microencapsulation into a biopolymer matrix composed of milk proteins and inulin. Two extracts were obtained using black rice flour as a raw material and hot water and ethanol as solvents. Both powders (called P1 for aqueous extract and P2 for ethanolic extract) proved to be rich sources of valuable bioactives, with microencapsulation efficiency up to 80%, both for anthocyanins and lactic acid bacteria. A higher content of anthocyanins was found in P1, of 102.91 ± 1.83 mg cyanindin-3-O-glucoside (C3G)/g dry weight (DW) when compared with only 27.60 ± 17.36 mg C3G/g DW in P2. The morphological analysis revealed the presence of large, thin, and fragile structures, with different sizes. A different pattern of gastric digestion was observed, with a highly protective effect of the matrix in P1 and a maximum decrease in anthocyanins of approximatively 44% in P2. In intestinal juice, the anthocyanins decreased significantly in P2, reaching a maximum of 97% at the end of digestion; whereas in P1, more than 45% from the initial anthocyanins content remained in the microparticles. Overall, the short-term storage stability test revealed a release of bioactive from P2 and a decrease in P1. The viable cells of lactic acid bacteria after 21 days of storage reached 7 log colony forming units (CFU)/g DW.

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Synthesis and Characterization of Polyphosphazenes Modified with Hydroxyethyl Methacrylate and Lactic Acid

International Journal of Polymer Science ◽

10.1155/2013/645869 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Evelyn Carolina Martínez Ceballos ◽

Ricardo Vera Graziano ◽

Gonzalo Martínez Barrera ◽

Oscar Olea Mejía

Keyword(s):

Lactic Acid ◽

Ring Opening ◽

Room Temperature ◽

Block Structure ◽

Ring Opening Polymerization ◽

Synthesis And Characterization ◽

Poly Lactic Acid ◽

Hydroxyethyl Methacrylate ◽

H Nmr

Poly(dichlorophosphazene) was prepared by melt ring-opening polymerization of the hexachlorocyclotriphosphazene. Poly[bis(2-hydroxyethyl-methacrylate)-phosphazene] and poly[(2-hydroxyethyl-methacrylate)-graft-poly(lactic-acid)-phosphazene] were obtained by nucleophilic condensation reactions at different concentrations of the substituents. The properties of the synthesized copolymers were assessed by FTIR,1H-NMR and31P-NMR, thermal analysis (DSC-TGA), and electron microscopy (SEM). The copolymers have a block structure and show twoTg's below room temperature. They are stable up to a temperature of 100°C. The type of the substituents attached to the PZ backbone determines the morphology of the polymers.

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Development of Four Unit Processes for Biobased PLA Manufacturing

ISRN Polymer Science ◽

10.5402/2012/938261 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Chae Hwan Hong ◽

Si Hwan Kim ◽

Ji-Yeon Seo ◽

Do Suck Han

Keyword(s):

Lactic Acid ◽

Ring Opening ◽

Lactic Acid Production ◽

Scale Up ◽

Catalyst System ◽

Ring Opening Polymerization ◽

Acid Fermentation ◽

Manufacturing Method ◽

Renewable Biomass ◽

Microbial Productivity

Polylactide (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and sugar beets, has attracted much attention for automotive parts application. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the stereocomplex PLA, we developed the four unit processes, fermentation, separation, lactide conversion, and polymerization. Fermentation of sugars to D-lactic acid is little studied, and its microbial productivity is not well known. Therefore, we investigated D-lactic acid fermentation with a view to obtaining the strains capable of producing D-lactic acid, and we got a maximum lactic acid production 60 g/L. Lactide is prepared by a two-step process: first, the lactic acid is converted into oligo(lactic acid) by a polycondensation reaction; second, the oligo(lactic acid) is thermally depolymerized to form the cyclic lactide via an unzipping mechanism. Through catalyst screening test for polycondensation and depolymerization reactions, we got a new method which shortens the whole reaction time 50% the level of the conventional method. Poly(L-lactide) was obtained from the ring-opening polymerization of L-lactide. We investigated various catalysts and polymerization conditions. Finally, we got the best catalyst system and the scale-up technology.

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