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Prakash Tamang J, Kharnaior P, Pariyar P. Whole genome sequencing of the poly-γ-glutamic acid-producing novel Bacillus subtilis Tamang strain, isolated from spontaneously fermented kinema. Food Res Int 2024; 190:114655. [PMID: 38945588 DOI: 10.1016/j.foodres.2024.114655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 06/14/2024] [Accepted: 06/15/2024] [Indexed: 07/02/2024]
Abstract
Kinema, a traditional fermented soybean food from the Himalayas, is well-liked for its sticky texture and flavourful umami taste. Among 175 bacterial strains from spontaneously fermented kinema samples, Bacillus subtilis Tamang strain stood out for its high stickiness and viscosity. The strain's Poly-γ-glutamic acid (γ-PGA) contains various groups of glutamic acid and has a molecular weight of 660 kDa. It demonstrates the ability to solubilize iron, preserve ferritin in Caco-2 cells, and exhibit antibacterial properties. The genome of B. subtilis Tamang is devoid of plasmid elements but does feature nine insert elements. Noteworthy is the presence of unique secondary metabolites with potential antimicrobial effects, such as amyloliquecidin GF610, bogorol A, and thermoactinoamide A. A total of 132 carbohydrate-active enzymes (CAZy) were identified, hinting at possible prebiotic characteristics. The genome analysis revealed genes responsible for γ-PGA production via the capBCA complex. Furthermore, genes associated with fibrinolytic activity, taste enhancement, biopeptides, immunomodulators, and vitamins like B12 and K2 were found, along with probiotics and various health benefits. The genetic material for L-asparaginase production, known for its anti-cancer properties, was also detected, as well as CRISPR-Cas systems. The absence of virulence factors and antimicrobial resistance genes confirms the safety of consuming B. subtilis Tamang as a food-grade bacterium.
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Affiliation(s)
- Jyoti Prakash Tamang
- Department of Microbiology, School of Life Sciences, Sikkim University, Science Building, Gangtok 737102, Sikkim, India.
| | - Pynhunlang Kharnaior
- Department of Microbiology, School of Life Sciences, Sikkim University, Science Building, Gangtok 737102, Sikkim, India
| | - Priyambada Pariyar
- Department of Microbiology, School of Life Sciences, Sikkim University, Science Building, Gangtok 737102, Sikkim, India
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He F, Gao B, Cheng X, Zhai J, Zhang X, Yang C, Jiewei T. High-level production of poly-γ-glutamic acid by a newly isolated Bacillus sp. YJY-8 and potential use in increasing the production of tomato. Prep Biochem Biotechnol 2024; 54:637-646. [PMID: 37768129 DOI: 10.1080/10826068.2023.2261058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Strain YJY-8, a new γ-polyglutamic acid producer, was separated from fermented soybean paste samples. The strain was identified as a genus of Bacillus by morphological and 16S rDNA sequence analysis and was named Bacillus sp. YJY-8. The optimal medium composition and cultural conditions were studied using a single-factor experiment and a response surface experiment. The optimized medium consisted of monosodium glutamate 70 g/L, glucose 54.3 g/L, glycerol 31.8 g/L, ammonium sulfate 11.1 g/L, yeast extract 3.2 g/L, tryptone 1.5 g/L, L-glutamic acid 6.8 g/L, MgSO4 7H2O 0.5 g/L, FeCl3 6H2O 0.02 g/L, KH2PO4 0.9 g/L, CaCl2 0.03 g/L, MnSO4 H2O 0.3 g/L, ammonium molybdate 0.02 g/L, pH 7.0. The optimal cultivation conditions were 35 °C and pH 7.0. Under the optimized conditions, after 48 hr of cultivation, the highest shaking flask fermentation level of γ-PGA reached 65.2 ± 0.36 g/L. In addition, through fed-batch fermentation in 30 L fermenters, the fermentation level of γ-PGA reached its highest level at 88.42 g/L and productivity was 1.23 g/(L hr) after 72 hr. Then, the effect of γ-PGA on tomato yield was investigated. At the seedling stage, the plant height and stem diameter of γ-PGA treated plants increased by 5.69 and 15.735% after spraying γ-PGA for 19 days. During the flowering and fruiting period, the stem diameter of the γ-PGA treatment group increased by 6.74%, with a maximum increase of 11.65%. The number of fruit branches increased by 0.56-16.29% and the number of fruit sets increased by 1.01-28.47%. At the fruit maturation stage, the yield of tomatoes increased by 10.51, 14.27, and 5.83%.
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Affiliation(s)
- Fuming He
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Baojun Gao
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Xin Cheng
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Jiao Zhai
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Xinqing Zhang
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Chuanlun Yang
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
| | - Tian Jiewei
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, P.R. China
- Shan Dong Chambroad Holding Group Co., Ltd, Binzhou, P.R. China
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Light Industry, Textile & Food Engineering, Sichuan University, Chengdu, P.R. China
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Elbanna K, Alsulami FS, Neyaz LA, Abulreesh HH. Poly (γ) glutamic acid: a unique microbial biopolymer with diverse commercial applicability. Front Microbiol 2024; 15:1348411. [PMID: 38414762 PMCID: PMC10897055 DOI: 10.3389/fmicb.2024.1348411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 01/19/2024] [Indexed: 02/29/2024] Open
Abstract
Microbial biopolymers have emerged as promising solutions for environmental pollution-related human health issues. Poly-γ-glutamic acid (γ-PGA), a natural anionic polymeric compound, is composed of highly viscous homo-polyamide of D and L-glutamic acid units. The extracellular water solubility of PGA biopolymer facilitates its complete biodegradation and makes it safe for humans. The unique properties have enabled its applications in healthcare, pharmaceuticals, water treatment, foods, and other domains. It is applied as a thickener, taste-masking agent, stabilizer, texture modifier, moisturizer, bitterness-reducing agent, probiotics cryoprotectant, and protein crystallization agent in food industries. γ-PGA is employed as a biological adhesive, drug carrier, and non-viral vector for safe gene delivery in tissue engineering, pharmaceuticals, and medicine. It is also used as a moisturizer to improve the quality of hair care and skincare cosmetic products. In agriculture, it serves as an ideal stabilizer, environment-friendly fertilizer synergist, plant-growth promoter, metal biosorbent in soil washing, and animal feed additive to reduce body fat and enhance egg-shell strength.
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Affiliation(s)
- Khaled Elbanna
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Department of Agricultural Microbiology, Faculty of Agriculture, Fayoum University, Fayoum, Egypt
| | - Fatimah S Alsulami
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Leena A Neyaz
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Hussein H Abulreesh
- Department of Biology, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
- Research Laboratories Unit, Faculty of Science, Umm Al-Qura University, Makkah, Saudi Arabia
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Samal S, Banerjee S, Dey P, Rangarajan V. Production and characterization of a novel poly amino acid from a thermophilic bacterium, and preliminary testing of its coagulating potential for imminent wastewater treatment application. Int J Biol Macromol 2023; 246:125589. [PMID: 37385322 DOI: 10.1016/j.ijbiomac.2023.125589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 06/15/2023] [Accepted: 06/25/2023] [Indexed: 07/01/2023]
Abstract
The increasing demand for biopolymers across diverse fields, such as food, medicine, cosmetics, and environmental applications, has prompted researchers to explore novel molecules with enhanced functionalities that meet these demands. In this study, a thermophilic strain of Bacillus licheniformis was employed to produce a unique polyamino acid. This thermophilic isolate exhibited rapid growth at 50 °C in a sucrose mineral salts medium, resulting in a biopolymer concentration of 7.4 g/L. Interestingly, the biopolymer produced at different temperatures exhibited varying glass-transition temperatures (ranging from 87.86 °C to 104.11 °C) and viscosities (7.5 cP to 16.3 cP), suggesting that the fermentation temperature significantly influenced the degree of polymerization. Furthermore, the biopolymer was characterized using various techniques, including Thin Layer Chromatography (TLC), Fourier Transform Infrared (FTIR) spectroscopy, Liquid Chromatography-Electrospray Ionization-Mass Spectroscopy (LC-ESI MS), Nuclear Magnetic Resonance (NMR), and Differential Scanning Calorimetry-Thermogravimetric Analysis (DSC-TGA). The results revealed that the obtained biopolymer was a poly amino acid, with poly-γ-glutamic acid as the major monomeric component in the polymer backbone with a few appendages of aspartic acid residues in its side chain. Finally, the biopolymer demonstrated significant coagulation potential for water treatment applications, as evidenced by coagulation studies conducted under varying pH conditions using kaolin-clay as a model precipitant.
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Affiliation(s)
- Subhranshu Samal
- Department of Chemical Engineering, Birla Institute of Technology and Science Pilani K.K. Birla Goa Campus, 403726, India
| | - Subhadeep Banerjee
- Department of Chemistry, Birla Institute of Technology and Science Pilani K.K. Birla Goa Campus, 403726, India
| | - Pinaki Dey
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Thiruvananthapuram, Kerala, India
| | - Vivek Rangarajan
- Department of Chemical Engineering, Birla Institute of Technology and Science Pilani K.K. Birla Goa Campus, 403726, India.
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Li D, Hou L, Gao Y, Tian Z, Fan B, Wang F, Li S. Recent Advances in Microbial Synthesis of Poly-γ-Glutamic Acid: A Review. Foods 2022; 11:foods11050739. [PMID: 35267372 PMCID: PMC8909396 DOI: 10.3390/foods11050739] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/12/2022] [Accepted: 02/26/2022] [Indexed: 02/01/2023] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) is a natural, safe, non-immunogenic, biodegradable, and environmentally friendly glutamic biopolymer. γ-PGA has been regarded as a promising bio-based materials in the food field, medical field, even in environmental engineering field, and other industrial fields. Microbial synthesis is an economical and effective way to synthesize γ-PGA. Bacillus species are the most widely studied producing strains. γ-PGA biosynthesis involves metabolic pathway of racemization, polymerization, transfer, and catabolism. Although microbial synthesis of γ-PGA has already been used extensively, productivity and yield remain the major constraints for its industrial application. Metabolic regulation is an attempt to solve the above bottleneck problems and meet the demands of commercialization. Therefore, it is important to understand critical factors that influence γ-PGA microbial synthesis in depth. This review focuses on production strains, biosynthetic pathway, and metabolic regulation. Moreover, it systematically summarizes the functional properties, purification procedure, and industrial application of γ-PGA.
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Affiliation(s)
- Danfeng Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
| | - Lizhen Hou
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
| | - Yaxin Gao
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
| | - Zhiliang Tian
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
| | - Bei Fan
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Fengzhong Wang
- Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Chinese Academy of Agricultural Sciences, Beijing 100193, China
- Correspondence: (F.W.); (S.L.); Tel.: +86-010-62815977 (F.W.); +86-010-62810295 (S.L.)
| | - Shuying Li
- Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, No. 2 Yuan Ming Yuan West Road, Beijing 100193, China; (D.L.); (L.H.); (Y.G.); (Z.T.); (B.F.)
- Correspondence: (F.W.); (S.L.); Tel.: +86-010-62815977 (F.W.); +86-010-62810295 (S.L.)
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Efficient production of poly-γ-glutamic acid by Bacillus velezensis via solid-state fermentation and its application. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.101575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Thapa P, Thapa A, Khadka S, Sapkota S, Panta OP, Sharma S, Karki TB, Poudel P. Screening and characterization of potent poly glutamic acid producing Bacillus sp. isolated from Kinema, water and soil samples. Heliyon 2021; 7:e07715. [PMID: 34401591 PMCID: PMC8358410 DOI: 10.1016/j.heliyon.2021.e07715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/18/2021] [Accepted: 08/02/2021] [Indexed: 12/30/2022] Open
Abstract
Microbially produced gamma poly glutamic acid (γ-PGA) is a commercially important biopolymer with many applications in foods and various other substances and are abundantly used in different parts of the world. With an aim to study the potent γ-PGA producing Bacillus species, a total of 47 different samples (Kinema, soil, and water) were randomly collected from different locations across the country, and Bacillus sp. were selectively isolated, screened, and characterized by performing physiological, biochemical, morphological, and 16S rRNA gene sequencing. The microbial production of γ-PGA was assayed with the selected isolates on the PGA medium and the metabolite obtained was recovered by ethanol precipitation method and further characterized by thin-layer chromatography (TLC). Thermotolerance (25-60 °C), pH tolerance (4-9), and NaCl tolerance (1-9%) tests were performed to optimize the bacterial growth and γ-PGA production and its viscosity were measured by Ostwald's viscometer. Out of 145 randomly selected colonies, 63 isolates were Gram-positive, rods, and endospore producers and were presumptively confirmed as genus Bacillus. Higher growth of γ-PGA producers were reported in 22 isolates and was found at optimum conditions such as temperature (30-37 °C), pH (6.5-7), incubation time (3 days), and NaCl concentration (3%) and γ-PGA thus produced was further verified by TLC with the retention factor (RF) value 0.27. The potent isolates were closely similar to Bacillus subtilis subsp. stercoris, Bacillus cereus, Bacillus paranthracis, and Bacillus licheniformis etc. Based on the findings of the study, B. licheniformis is the most potent γ-PGA producing Bacillus sp. which can further be used for the commercial production of γ-PGA. To the best of our knowledge, there is yet no published research from Nepal showing the production of the γ-PGA although microbially produced γ-PGA are the major constituents in some popular foods in particular communities of the country.
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Affiliation(s)
- Punam Thapa
- Department of Microbiology, National College (NIST), Tribhuvan University, P.O. Box: 8659, Khusibu, Naya Bazar, Kathmandu, Nepal
| | - Alina Thapa
- State Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sujan Khadka
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sanjeep Sapkota
- State Key Laboratory of Respiratory Disease, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, 510530, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Om Prakash Panta
- Department of Microbiology, National College (NIST), Tribhuvan University, P.O. Box: 8659, Khusibu, Naya Bazar, Kathmandu, Nepal
| | - Suprina Sharma
- Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu, 44601, Nepal
| | - Tika Bahadur Karki
- Department of Microbiology, National College (NIST), Tribhuvan University, P.O. Box: 8659, Khusibu, Naya Bazar, Kathmandu, Nepal
| | - Pramod Poudel
- Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu, 44618, Nepal.,Research Division, University Grants Commission (UGC), P.O. Box: 10796, Sanothimi, Bhaktapur, Nepal
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Zhang R, Zhang S, Jiang G, Gan L, Xu Z, Tian Y. Optimization of fermentation conditions, purification and rheological properties of poly (γ-glutamic acid) produced by Bacillus subtilis 1006-3. Prep Biochem Biotechnol 2021; 52:302-310. [PMID: 34236935 DOI: 10.1080/10826068.2021.1941103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
This study aimed to investigate the optimal fermentation condition, purification and rheological properties of extracellular polymers produced by Bacillus subtilis 1006-3. An optimum temperature of 30.2 °C, inoculation amount of 6.1%, and pH of 8.2 were determined via Response Surface Methodology. The result of amino acid analysis and gel electrophoresis indicated that the obtained polymer contained only glutamic acid, with a wide molecular weight range. This polymer was finally determined as γ-PGA by infrared spectroscopy. The γ-PGA solution displayed a behavior of pseudoplastic non-Newtonian fluid with shear thinning properties, which can be described by the Ostward-de Waele power law model. The apparent viscosity of γ-PGA solution increased with the increase in its concentration from 1% to 10%. The deviation in pH from neutral value, and the addition of NaCl or MgCl2 can reduce the apparent viscosity of γ-PGA solution, and it was more sensitive to Mg2+ than to Na+ addition. At the concentration of 4, 6, and 8%, γ-PGA solution showed predominantly viscous response in the range of 0.1-100 rad/s angular frequency (G″>G'). These results indicated the potential application of the γ-PGA as a thickening agent.
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Affiliation(s)
- Ruoshi Zhang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
| | - Shihao Zhang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
| | - Guangyang Jiang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
| | - Longzhan Gan
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
| | - Zhe Xu
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
| | - Yongqiang Tian
- College of Biomass Science and Engineering, Sichuan University, Chengdu, P. R. China.,Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, P. R. China
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Ajayeoba TA, Dula S, Ijabadeniyi OA. Properties of Poly-γ-Glutamic Acid Producing- Bacillus Species Isolated From Ogi Liquor and Lemon- Ogi Liquor. Front Microbiol 2019; 10:771. [PMID: 31057503 PMCID: PMC6481274 DOI: 10.3389/fmicb.2019.00771] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 03/26/2019] [Indexed: 11/13/2022] Open
Abstract
Poly-γ-glutamic acid (γPGA) is a natural and promising biopolymer synthesized by Bacillus spp. during fermentation. This study isolated Bacillus spp. from ogi steep liquor (OSL) and lemon-ogi steep liquor (LOSL) using standard methods and determined the γPGA-producing ability. The antimicrobial and angiotensin-converting enzyme (ACE) inhibitory activities of γPGA polymer were evaluated and isolates were sequenced. Four isolates (TA004, TA006, TA011, TA012) selected based on phenotypic characterization and stickiness (<15 cm) showed antibacterial activity against different pathogens with the highest activity found in TA004 (22.5 mm) and least in TA011 (16.6 mm). Furthermore, time-kill assay showed that the combined γPGA polymer was more effective and demonstrated bactericidal activity over individual γPGA which are bacteriostatic in nature. All γPGA polymer exhibited ACE properties except TA011. The highest IC50 was observed in TA006 (0.11 mg/ml) and least in TA004 (0.35 mg/ml). TA004 had the highest molecular weight (261 kDa) while TA011 had the least (194.97 kDa). In addition, all γPGA exhibited characteristic peaks at 3413-3268 cm-1 and 1722-1664 cm-1 that corresponded to amine N-H stretching intensities and C = O stretching in COOH. Bacillus isolates were identified as TA004 (B. subtilis-GenBank: MH782061), TA006 (B. amyloliquefaciens- GenBank: MH782075), TA011 (B. subtilis- GenBank: MH782088), TA012 (B. subtilis- GenBank: MH782083). OSL and LOSL have the potential for developing functional foods with a valuable effect on health.
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Affiliation(s)
- Titilayo A. Ajayeoba
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban, South Africa
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10
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Purification of extra cellular poly-γ-glutamic acid as an antibacterial agent using anion exchange chromatography. Int J Biol Macromol 2018; 113:142-149. [DOI: 10.1016/j.ijbiomac.2018.02.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 12/19/2017] [Accepted: 02/12/2018] [Indexed: 11/19/2022]
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11
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Microbial production of poly-γ-glutamic acid. World J Microbiol Biotechnol 2017; 33:173. [DOI: 10.1007/s11274-017-2338-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 08/30/2017] [Indexed: 10/18/2022]
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12
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Roy P, Saha SK, Banerjee P, Dey S, Sukul D. Experimental and theoretical investigation towards anti-corrosive property of glutamic acid and poly-γ-glutamic acid for mild steel in 1 M HCl: intramolecular synergism due to copolymerization. RESEARCH ON CHEMICAL INTERMEDIATES 2017. [DOI: 10.1007/s11164-017-2887-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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