1
|
Šovljanski O, Ranitović A, Tomić A, Ćetković N, Miljković A, Saveljić A, Cvetković D. Synergistic Strategies of Heat and Peroxyacetic Acid Disinfection Treatments for Salmonella Control. Pathogens 2023; 12:1336. [PMID: 38003799 PMCID: PMC10674339 DOI: 10.3390/pathogens12111336] [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: 10/18/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023] Open
Abstract
The food industry has recognized a pressing need for highly effective disinfection protocols to decrease the risk of pathogen emergence and proliferation in food products. The integration of antimicrobial treatments in food production has occurred as a potential strategy to attain food items of superior quality with respect to microbiological safety and sensory attributes. This study aims to investigate the individual and synergistic effects of heat and peroxyacetic acid on the inactivation of bacterial cells, considering various contact times and environmental conditions. Four Salmonella serotypes, isolated from industrial meat production surfaces, were employed as model organisms. By systematically assessing the impacts of individual factors and synergistic outcomes, the effectiveness of bacterial cell inactivation and the efficiency of heat and peroxyacetic acid could be predicted. To better approximate real-world food processing conditions, this study also incorporated a bovine albumin-rich condition as a simulation of the presence of organic loads in processing steps. The findings revealed the essential need for a synergistic interplay of investigated parameters with the following optimized values: 1.5% concentration of peroxyacetic acid, temperature range of 60-65 °C, and contact time of 3 min for the complete effect regardless of the degree of contamination.
Collapse
Affiliation(s)
- Olja Šovljanski
- Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (A.R.); (A.T.); (A.S.); (D.C.)
| | - Aleksandra Ranitović
- Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (A.R.); (A.T.); (A.S.); (D.C.)
| | - Ana Tomić
- Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (A.R.); (A.T.); (A.S.); (D.C.)
| | - Nenad Ćetković
- Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia; (N.Ć.); (A.M.)
| | - Ana Miljković
- Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia; (N.Ć.); (A.M.)
| | - Anja Saveljić
- Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (A.R.); (A.T.); (A.S.); (D.C.)
| | - Dragoljub Cvetković
- Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia; (A.R.); (A.T.); (A.S.); (D.C.)
| |
Collapse
|
2
|
Carter MS, Tuttle MJ, Mancini JA, Martineau R, Hung CS, Gupta MK. Microbially Induced Calcium Carbonate Precipitation by Sporosarcina pasteurii: a Case Study in Optimizing Biological CaCO 3 Precipitation. Appl Environ Microbiol 2023; 89:e0179422. [PMID: 37439668 PMCID: PMC10467343 DOI: 10.1128/aem.01794-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2023] Open
Abstract
Current production of traditional concrete requires enormous energy investment that accounts for approximately 5 to 8% of the world's annual CO2 production. Biocement is a building material that is already in industrial use and has the potential to rival traditional concrete as a more convenient and more environmentally friendly alternative. Biocement relies on biological structures (enzymes, cells, and/or cellular superstructures) to mineralize and bind particles in aggregate materials (e.g., sand and soil particles). Sporosarcina pasteurii is a workhorse organism for biocementation, but most research to date has focused on S. pasteurii as a building material rather than a biological system. In this review, we synthesize available materials science, microbiology, biochemistry, and cell biology evidence regarding biological CaCO3 precipitation and the role of microbes in microbially induced calcium carbonate precipitation (MICP) with a focus on S. pasteurii. Based on the available information, we provide a model that describes the molecular and cellular processes involved in converting feedstock material (urea and Ca2+) into cement. The model provides a foundational framework that we use to highlight particular targets for researchers as they proceed into optimizing the biology of MICP for biocement production.
Collapse
Affiliation(s)
- Michael S. Carter
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
- Biological and Nanoscale Technologies Division, UES, Inc., Dayton, Ohio, USA
| | - Matthew J. Tuttle
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
- Biological and Nanoscale Technologies Division, UES, Inc., Dayton, Ohio, USA
| | - Joshua A. Mancini
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
- Biological and Nanoscale Technologies Division, UES, Inc., Dayton, Ohio, USA
| | - Rhett Martineau
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
- Biological and Nanoscale Technologies Division, UES, Inc., Dayton, Ohio, USA
| | - Chia-Suei Hung
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
| | - Maneesh K. Gupta
- Materials and Manufacturing Directorate Air Force Research Lab, Wright-Patterson Air Force Base, Dayton, Ohio, USA
| |
Collapse
|
3
|
Hu XM, Liu JD, Feng Y, Zhao YY, Wang XW, Liu WH, Zhang M, Liu Y. Application of urease-producing microbial community in seawater to dust suppression in desert. ENVIRONMENTAL RESEARCH 2023; 219:115121. [PMID: 36549485 DOI: 10.1016/j.envres.2022.115121] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/08/2022] [Accepted: 12/18/2022] [Indexed: 06/17/2023]
Abstract
In order to solve the dust problem caused by sandstorms, this paper aims to propose a new method of enriching urease-producing microbial communities in seawater in a non-sterile environment. Besides, the difference of dust suppression performance of enriched microorganisms under different pH conditions was also explored to adapt the dust. The Fourier-transform infrared spectrometry (FTIR) and Scanning electron microscopy (SEM) confirmed the formation of CaCO3. The X-ray diffraction (XRD) further showed that the crystal forms of CaCO3 were calcite and vaterite. When urease activity was equivalent, the alkaline environment was conducive to the transformation of CaCO3 to more stable calcite. The mineralization rate at pH = 10 reached the maximum value on the 7th day, which was 97.49 ± 1.73%. Moreover, microbial community analysis results showed that the relative abundance of microbial community structure was different under different pH enrichment. Besides, the relative abundance of Sporosarcina, a representative genus of urease-producing microbial community, increased with the increase of pH under culture conditions, which consistent with the mineralization performance results. In addition, the genus level species network diagram also showed that in the microbial community, Sporosarcina was negatively correlated with another urease-producing genus Bacillus, and had a reciprocal relationship with Atopostipes, which means that the urease-producing microbial community was structurally stable. The enrichment of urease-producing microbial communities in seawater will provide empirical support for the large-scale engineering application of MICP technology in preventing and controlling sandstorms in deserts.
Collapse
Affiliation(s)
- Xiang-Ming Hu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Jin-Di Liu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Yue Feng
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Yan-Yun Zhao
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Xu-Wei Wang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Wen-Hao Liu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Ming Zhang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China
| | - Yu Liu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China; State Key Laboratory of Mine Lab Disaster Prevention and Control Co-found by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao 266590, Shandong, China.
| |
Collapse
|
4
|
Zhang P, Liu XQ, Yang LY, Sheng HZY, Qian AQ, Fan T. Immobilization of Cd 2+ and Pb 2+ by biomineralization of the carbonate mineralized bacterial consortium JZ1. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:22471-22482. [PMID: 36301386 DOI: 10.1007/s11356-022-23587-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Microbially induced carbonate precipitation (MICP) has been proven to effectively immobilize Cd2+ and Pb2+ using a single bacterium. However, there is an urgent need for studies of Cd2+ and Pb2+ immobilized by a bacterial consortium. In this study, a stable consortium designated JZ1 was isolated from soil that was contaminated with cadmium and lead, and the dominant genus Sporosarcina (99.1%) was found to have carbonate mineralization function. The results showed that 91.52% and 99.38% of Cd2+ and Pb2+ were mineralized by the consortium JZ1 with 5 g/L CaCl2 at an initial concentration of 5 mg/L Cd2+ and 150 mg/L Pb2+, respectively. The bioprecipitates were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Moreover, the kinetic studies indicated that the urea hydrolysis reaction fit well with the Michaelis-Menten equation, and the kinetic parameters Km and Vmax were estimated to be 38.69 mM and 58.98 mM/h, respectively. When the concentration of urea increased from 0.1 to 0.3 M, the mineralization rate increased by 1.58-fold. This study can provide a novel microbial resource for the biomineralization of Cd and Pb in soil and water environments.
Collapse
Affiliation(s)
- Peng Zhang
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Xiao-Qiang Liu
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Li-Yuan Yang
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Hua-Ze-Yu Sheng
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - An-Qi Qian
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China
| | - Ting Fan
- Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention, College of Resources and Environment, Anhui Agricultural University, Hefei, China.
| |
Collapse
|
5
|
Sun Y, Zhong X, Lv J, Wang G. Experimental Study on Silt Soil Improved by Microbial Solidification with the Use of Lignin. Microorganisms 2023; 11:microorganisms11020281. [PMID: 36838245 PMCID: PMC9965713 DOI: 10.3390/microorganisms11020281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/05/2023] [Accepted: 01/12/2023] [Indexed: 01/27/2023] Open
Abstract
At present, in the field of geotechnical engineering and agricultural production, with increasingly serious pollution an environmentally friendly and efficient means is urgently needed to improve the soil mass. This paper mainly studied the microbial induced calcium carbonate precipitation (MICP) technology and the combined effect of MICP technology and lignin on the improvement of silt in the Beijing area. Through unconfined compressive strength and dynamic triaxial test methods, samples improved by microorganisms were studied to obtain the optimal values of cement concentration and lignin under these two test schemes. The results show that after the incubation time of Sporosarcina pasteurii reached 24 h, the OD600 value was 1.7-2.0 and the activity value (U) was 930-1000 mM ms/min. In the unconfined static pressure strength test, after MICP treatment the optimal concentration of cementitious solution for constant temperature and humidity samples and constant-temperature immersion samples was 1.25 mol/L. The compressive strength of the constant temperature and humidity sample was 1.73 MPa, and the compressive strength of the constant-temperature immersion sample was 3.62 Mpa. At the concentration of 1.25 mol/L of cement solution, MICP technology combined with lignin could improve the constant temperature and humidity silt sample. The optimal addition ratio of lignin was 4%, and its compressive strength was 1.9 MPa. The optimal lignin addition ratio of the sample soaked at a constant temperature was 3%, and the compressive strength was 4.84 MPa. In the dynamic triaxial multi-stage cyclic load test, the optimal concentration of cementation solution for the constant temperature and humidity sample after MICP treatment was 1.0 mol/L, and the failure was mainly inclined cracks. However, in the condition of joint improvement of MICP and lignin, the sample mainly had a drum-shaped deformation, the optimal lignin addition ratio was 4%, and the maximum axial load that the sample could bear was 306.08 N. When the axial dynamic load reached 300 N, the strain accumulation of the 4% group was only 2.3 mm. In this paper, lignin, an ecofriendly material, was introduced on the basis of MICP technology. According to the failure shape and relevant results of the sample, the addition of lignin was beneficial for the improvement of the compressive strength of the sample.
Collapse
Affiliation(s)
- Yongshuai Sun
- College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China
- Correspondence:
| | - Xinyan Zhong
- School of Engineering and Technology, China University of Geosciences, Beijing 100083, China
| | - Jianguo Lv
- School of Engineering and Technology, China University of Geosciences, Beijing 100083, China
| | - Guihe Wang
- School of Engineering and Technology, China University of Geosciences, Beijing 100083, China
| |
Collapse
|
6
|
Răut I, Constantin M, Petre I, Raduly M, Radu N, Gurban AM, Doni M, Alexandrescu E, Nicolae CA, Jecu L. Highlighting Bacteria with Calcifying Abilities Suitable to Improve Mortar Properties. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7259. [PMID: 36295324 PMCID: PMC9612027 DOI: 10.3390/ma15207259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
Biomineralization, the use of microorganisms to produce calcium carbonate, became a green solution for application in construction materials to improve their strength and durability. The calcifying abilities of several bacteria were investigated by culturing on a medium with urea and calcium ions. The characterization of the precipitates from bacterial cultures was performed using X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The formation of carbonate crystals was demonstrated by optical and scanning electron microscopy. Water absorption and compressive strength measurements were applied to mortars embedded with sporal suspension. The efficiency of the supplementation of mortar mixtures with bacterial cells was evaluated by properties, namely the compressive strength and the water absorption, which are in a relationship of direct dependence, the increase in compressive strength implying the decrease in water absorption. The results showed that Bacillus subtilis was the best-performing bacterium, its introduction into the mortar producing an increase in compressive strength by 11.81% and 9.50%, and a decrease in water absorption by 11.79% and 10.94%, after 28 and 56 days of curing, respectively, as compared to standards. The exploitation of B. subtilis as a calcifying agent can be an interesting prospect in construction materials.
Collapse
Affiliation(s)
- Iuliana Răut
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Mariana Constantin
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
- Faculty of Pharmacy, Titu Maiorescu University, 16 Bd. Gheorghe Sincai, 040441 Bucharest, Romania
| | - Ionela Petre
- CEPROCIM S.A., 6 Preciziei Street, 062203 Bucharest, Romania
| | - Monica Raduly
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Nicoleta Radu
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
- Faculty of Biotechnology, University of Agronomic Sciences and Veterinary Medicine of Bucharest, 59 Mărăşti Boulevard, 011464 Bucharest, Romania
| | - Ana-Maria Gurban
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Mihaela Doni
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Elvira Alexandrescu
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Cristi-Andi Nicolae
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| | - Luiza Jecu
- National Institute for Research & Development in Chemistry and Petrochemistry-ICECHIM, 202 Independentei Splai, 060021 Bucharest, Romania
| |
Collapse
|
7
|
Šovljanski O, Tomić A, Markov S. Relationship between Bacterial Contribution and Self-Healing Effect of Cement-Based Materials. Microorganisms 2022; 10:microorganisms10071399. [PMID: 35889117 PMCID: PMC9322135 DOI: 10.3390/microorganisms10071399] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/07/2022] [Accepted: 07/10/2022] [Indexed: 02/07/2023] Open
Abstract
The civil research community has been attracted to self-healing bacterial-based concrete as a potential solution in the economy 4.0 era. This concept provides more sustainable material with a longer lifetime due to the reduction of crack appearance and the need for anthropogenic impact. Regardless of the achievements in this field, the gap in the understanding of the importance of the bacterial role in self-healing concrete remains. Therefore, understanding the bacterial life cycle in the self-healing effect of cement-based materials and selecting the most important relationship between bacterial contribution, self-healing effect, and material characteristics through the process of microbiologically (bacterially) induced carbonate precipitation is just the initial phase for potential applications in real environmental conditions. The concept of this study offers the possibility to recognize the importance of the bacterial life cycle in terms of application in extreme conditions of cement-based materials and maintaining bacterial roles during the self-healing effect.
Collapse
|
8
|
Šovljanski O, Pezo L, Grahovac J, Tomić A, Ranitović A, Cvetković D, Markov S. Best-performing Bacillus strains for microbiologically induced CaCO3 precipitation: Screening of relative influence of operational and environmental factors. J Biotechnol 2022; 350:31-41. [DOI: 10.1016/j.jbiotec.2022.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 03/14/2022] [Accepted: 04/07/2022] [Indexed: 12/15/2022]
|
9
|
Modification of Surfaces with Vaterite CaCO3 Particles. MICROMACHINES 2022; 13:mi13030473. [PMID: 35334765 PMCID: PMC8954061 DOI: 10.3390/mi13030473] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 02/07/2023]
Abstract
Former studies have demonstrated a strong interest toward the crystallization of CaCO3 polymorphs in solution. Nowadays, CaCO3 crystallization on solid surfaces is extensively being studied using biomolecules as substrates for the control of the growth aiming at various applications of CaCO3. Calcium carbonate exists in an amorphous state, as three anhydrous polymorphs (aragonite, calcite and vaterite), and as two hydrated polymorphs (monohydrocalcite and ikaite). The vaterite polymorph is considered as one of the most attractive forms due to its large surface area, biocompatibility, mesoporous nature, and other features. Based on physical or chemical immobilization approaches, vaterite can be grown directly on solid surfaces using various (bio)molecules, including synthetic polymers, biomacromolecules such as proteins and peptides, carbohydrates, fibers, extracellular matrix components, and even biological cells such as bacteria. Herein, the progress on the modification of solid surfaces by vaterite CaCO3 crystals is reviewed, focusing on main findings and the mechanism of vaterite growth initiated by various substances mentioned above, as well as the discussion of the applications of such modified surfaces.
Collapse
|
10
|
Abstract
The growing need for industrial production of bio-based acetoin and 2,3-butanediol (2,3-BD) is due to both environmental concerns, and their widespread use in the food, pharmaceutical, and chemical industries. Acetoin is a common spice added to many foods, but also a valuable reagent in many chemical syntheses. Similarly, 2,3-BD is an indispensable chemical on the platform in the production of synthetic rubber, printing inks, perfumes, antifreeze, and fuel additives. This state-of-the-art review focuses on representatives of the genus Bacillus as prospective producers of acetoin and 2,3-BD. They have the following important advantages: non-pathogenic nature, unpretentiousness to growing conditions, and the ability to utilize a huge number of substrates (glucose, sucrose, starch, cellulose, and inulin hydrolysates), sugars from the composition of lignocellulose (cellobiose, mannose, galactose, xylose, and arabinose), as well as waste glycerol. In addition, these strains can be improved by genetic engineering, and are amenable to process optimization. Bacillus spp. are among the best acetoin producers. They also synthesize 2,3-BD in titer and yield comparable to those of the pathogenic producers. However, Bacillus spp. show relatively lower productivity, which can be increased in the course of challenging future research.
Collapse
|
11
|
Petrova P, Arsov A, Ivanov I, Tsigoriyna L, Petrov K. New Exopolysaccharides Produced by Bacillus licheniformis 24 Display Substrate-Dependent Content and Antioxidant Activity. Microorganisms 2021; 9:microorganisms9102127. [PMID: 34683448 PMCID: PMC8540526 DOI: 10.3390/microorganisms9102127] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/01/2021] [Accepted: 10/08/2021] [Indexed: 01/18/2023] Open
Abstract
Bacillus licheniformis is a soil bacterium with many industrial applications. In addition to enzymes, platform chemicals, antibiotics and phytohormones, the species produces exopolysaccharides (EPSs) of various biological activities. This study revealed that Bulgarian isolate B. licheniformis 24 produced EPSs consisting of galactose, glucose and mannose with substrate-dependent ratio. From glucose, B. licheniformis 24 secreted EPS1, consisting of 54% galactose, 39% glucose and 7% mannose. From fructose, the strain formed EPS2, containing 51% glucose, 30% mannose and 19% galactose. Batch cultivation in flasks yielded 2.2–2.6 g/L EPS1 and 1.90–2.11 g/L EPS2. Four to five times higher yields of EPS were obtained from both substrates during batch and fed-batch processes in a fermenter at 37.8 °C, pH 6.2 and aeration 3.68 vvm. The batch process with 200 g/L of starting substrates received 9.64 g/L EPS1 and 6.29 g/L EPS2, reaching maximum values at the 33rd and 24th h, respectively. Fed-batch fermentation resulted in the highest yields, 12.61 g/L EPS1 and 7.03 g/L EPS2. In all processes, EPSs were produced only in the exponential growth phase. Both EPSs exhibited antioxidant activity, but EPS2 was much more potent in this regard, reaching 811 μM Vitamin C Equivalent Antioxidant Capacity (versus 135 μM for EPS1). EPS1 displayed antibacterial activity against a non-O1 strain of Vibrio cholerae.
Collapse
Affiliation(s)
- Penka Petrova
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (A.A.); (I.I.)
- Correspondence: (P.P.); (K.P.)
| | - Alexander Arsov
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (A.A.); (I.I.)
| | - Ivan Ivanov
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (A.A.); (I.I.)
| | - Lidia Tsigoriyna
- Institute of Chemical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria;
| | - Kaloyan Petrov
- Institute of Chemical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria;
- Correspondence: (P.P.); (K.P.)
| |
Collapse
|