Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG
This study evaluated the ability of two strains of bacterial starter cultures, Lactobacillus casei AP (AP) and Lactobacillus casei AG (AG), to produce exopolysaccharides (EPSs). First, the physicochemical properties of the fermented milk produced by AP and AG were assessed, including physical qualit...
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| Format: | Article |
| Language: | English |
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AIMS Press
2022-04-01
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| Series: | AIMS Microbiology |
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| Online Access: | https://www.aimspress.com/article/doi/10.3934/microbiol.2022012?viewType=HTML |
| _version_ | 1818490051768614912 |
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| author | Hafidh Shofwan Maajid Nurliyani Nurliyani Widodo Widodo |
| author_facet | Hafidh Shofwan Maajid Nurliyani Nurliyani Widodo Widodo |
| author_sort | Hafidh Shofwan Maajid |
| collection | DOAJ |
| description | This study evaluated the ability of two strains of bacterial starter cultures, Lactobacillus casei AP (AP) and Lactobacillus casei AG (AG), to produce exopolysaccharides (EPSs). First, the physicochemical properties of the fermented milk produced by AP and AG were assessed, including physical qualities like viscosity and syneresis and chemical qualities, such as pH, acidity, protein, lactose, fat content, and total solid. Then, AP and AG's ability to produce EPS was measured. Additionally, the EPS' microstructure was observed using a scanning electron microscope, and its chemical structure was assessed using Fourier transform-infrared (FT-IR) spectroscopy. Also, AP and AG's ability to produce EPS was tracked at the molecular level by studying the glycosyltransferase (gtf) gene. Statistical analysis showed that the milk fermented using AP and AG had similar physicochemical qualities (P > 0.05) but significantly different physical qualities (P < 0.05). Additionally, the milk fermented with AP had lower viscosity (1137.33 ± 34.31 centiPoise) than AG (1221.50 ± 20.66 centiPoise). In addition, the milk fermented using AP had higher syneresis (19.42%) than AG (17.83%). The higher viscosity and lower syneresis in the milk fermented using AG were associated with AG's ability to produce more EPS (1409 mg/L) than AP (1204 mg/L). In addition, according to the FT-IR analysis, the AP- and AG-synthesized EPS contained absorption bands at 3323, 2980, 2901, 1642, 1084, 1043, and 873 cm−1. The absorption band at 1642 and 2980 cm−1 corresponds to carbonyl and methylene groups, respectively. Absorption band 873 cm−1 is characteristic of the α-glycosidic bond of α-glucan in EPS. Moreover, the absorption bands on the wavelength region corresponding to the functional groups in the AP- and AG-produced EPS were similar to those in commercially available EPS. Lastly, gtf, contributing to EPS synthesis, was found in the genomes of AP and AG, suggesting the role of glycosyltransferase in the EPS synthesis by both strains. |
| first_indexed | 2024-12-10T17:12:02Z |
| format | Article |
| id | doaj.art-0854bcfe43084f1c8de931b4879bba11 |
| institution | Directory Open Access Journal |
| issn | 2471-1888 |
| language | English |
| last_indexed | 2024-12-10T17:12:02Z |
| publishDate | 2022-04-01 |
| publisher | AIMS Press |
| record_format | Article |
| series | AIMS Microbiology |
| spelling | doaj.art-0854bcfe43084f1c8de931b4879bba112022-12-22T01:40:16ZengAIMS PressAIMS Microbiology2471-18882022-04-018213815210.3934/microbiol.2022012Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AGHafidh Shofwan Maajid0Nurliyani Nurliyani1Widodo Widodo2Faculty of Animal Science, Universitas Gadjah Mada, Yogyakarta, IndonesiaFaculty of Animal Science, Universitas Gadjah Mada, Yogyakarta, IndonesiaFaculty of Animal Science, Universitas Gadjah Mada, Yogyakarta, IndonesiaThis study evaluated the ability of two strains of bacterial starter cultures, Lactobacillus casei AP (AP) and Lactobacillus casei AG (AG), to produce exopolysaccharides (EPSs). First, the physicochemical properties of the fermented milk produced by AP and AG were assessed, including physical qualities like viscosity and syneresis and chemical qualities, such as pH, acidity, protein, lactose, fat content, and total solid. Then, AP and AG's ability to produce EPS was measured. Additionally, the EPS' microstructure was observed using a scanning electron microscope, and its chemical structure was assessed using Fourier transform-infrared (FT-IR) spectroscopy. Also, AP and AG's ability to produce EPS was tracked at the molecular level by studying the glycosyltransferase (gtf) gene. Statistical analysis showed that the milk fermented using AP and AG had similar physicochemical qualities (P > 0.05) but significantly different physical qualities (P < 0.05). Additionally, the milk fermented with AP had lower viscosity (1137.33 ± 34.31 centiPoise) than AG (1221.50 ± 20.66 centiPoise). In addition, the milk fermented using AP had higher syneresis (19.42%) than AG (17.83%). The higher viscosity and lower syneresis in the milk fermented using AG were associated with AG's ability to produce more EPS (1409 mg/L) than AP (1204 mg/L). In addition, according to the FT-IR analysis, the AP- and AG-synthesized EPS contained absorption bands at 3323, 2980, 2901, 1642, 1084, 1043, and 873 cm−1. The absorption band at 1642 and 2980 cm−1 corresponds to carbonyl and methylene groups, respectively. Absorption band 873 cm−1 is characteristic of the α-glycosidic bond of α-glucan in EPS. Moreover, the absorption bands on the wavelength region corresponding to the functional groups in the AP- and AG-produced EPS were similar to those in commercially available EPS. Lastly, gtf, contributing to EPS synthesis, was found in the genomes of AP and AG, suggesting the role of glycosyltransferase in the EPS synthesis by both strains.https://www.aimspress.com/article/doi/10.3934/microbiol.2022012?viewType=HTMLlactobacillus casei ap and agmilk fermentationexopolysaccharidesviscosityglycosyltransferase |
| spellingShingle | Hafidh Shofwan Maajid Nurliyani Nurliyani Widodo Widodo Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG AIMS Microbiology lactobacillus casei ap and ag milk fermentation exopolysaccharides viscosity glycosyltransferase |
| title | Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG |
| title_full | Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG |
| title_fullStr | Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG |
| title_full_unstemmed | Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG |
| title_short | Exopolysaccharide production in fermented milk using Lactobacillus casei strains AP and AG |
| title_sort | exopolysaccharide production in fermented milk using lactobacillus casei strains ap and ag |
| topic | lactobacillus casei ap and ag milk fermentation exopolysaccharides viscosity glycosyltransferase |
| url | https://www.aimspress.com/article/doi/10.3934/microbiol.2022012?viewType=HTML |
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