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Wagner PM, Salgado MA, Turani O, Fornasier SJ, Salvador GA, Smania AM, Bouzat C, Guido ME. Rhythms in lipid droplet content driven by a metabolic oscillator are conserved throughout evolution. Cell Mol Life Sci 2024; 81:348. [PMID: 39136766 PMCID: PMC11335272 DOI: 10.1007/s00018-024-05355-4] [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] [Received: 03/04/2024] [Revised: 07/02/2024] [Accepted: 07/08/2024] [Indexed: 08/22/2024]
Abstract
The biological clock in eukaryotes controls daily rhythms in physiology and behavior. It displays a complex organization that involves the molecular transcriptional clock and the redox oscillator which may coordinately work to control cellular rhythms. The redox oscillator has emerged very early in evolution in adaptation to the environmental changes in O2 levels and has been shown to regulate daily rhythms in glycerolipid (GL) metabolism in different eukaryotic cells. GLs are key components of lipid droplets (LDs), intracellular storage organelles, present in all living organisms, and essential for energy and lipid homeostasis regulation and survival; however, the cell bioenergetics status is not constant across time and depends on energy demands. Thus, the formation and degradation of LDs may reflect a time-dependent process following energy requirements. This work investigated the presence of metabolic rhythms in LD content along evolution by studying prokaryotic and eukaryotic cells and organisms. We found sustained temporal oscillations in LD content in Pseudomonas aeruginosa bacteria and Caenorhabditis elegans synchronized by temperature cycles, in serum-shock synchronized human embryonic kidney cells (HEK 293 cells) and brain tumor cells (T98G and GL26) after a dexamethasone pulse. Moreover, in synchronized T98G cells, LD oscillations were altered by glycogen synthase kinase-3 (GSK-3) inhibition that affects the cytosolic activity of the metabolic oscillator or by knocking down LIPIN-1, a key GL synthesizing enzyme. Overall, our findings reveal the existence of metabolic oscillations in terms of LD content highly conserved across evolutionary scales notwithstanding variations in complexity, regulation, and cell organization.
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Affiliation(s)
- Paula M Wagner
- CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre s/n, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Mauricio A Salgado
- CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre s/n, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Ornella Turani
- INIBIBB-CONICET, Universidad Nacional del Sur, Departamento de Biología, Bioquímica y Farmacia, Camino de la Carrindanga, km 7, 8000, Bahía Blanca, Argentina
| | - Santiago J Fornasier
- CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre s/n, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Gabriela A Salvador
- INIBIBB-CONICET, Universidad Nacional del Sur, Departamento de Biología, Bioquímica y Farmacia, Camino de la Carrindanga, km 7, 8000, Bahía Blanca, Argentina
| | - Andrea M Smania
- CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre s/n, Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Cecilia Bouzat
- INIBIBB-CONICET, Universidad Nacional del Sur, Departamento de Biología, Bioquímica y Farmacia, Camino de la Carrindanga, km 7, 8000, Bahía Blanca, Argentina
| | - Mario E Guido
- CIQUIBIC-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina.
- Departamento de Química Biológica Ranwel Caputto, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre s/n, Ciudad Universitaria, 5000, Córdoba, Argentina.
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Liang W, Yang B, Bin L, Hu Y, Fan D, Chen W, Li P, Tang B. Intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge-membrane bioreactor by Acinetobacter junii. BIORESOURCE TECHNOLOGY 2024; 397:130474. [PMID: 38395234 DOI: 10.1016/j.biortech.2024.130474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/17/2024] [Accepted: 02/18/2024] [Indexed: 02/25/2024]
Abstract
This work aims at intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge (AGS) - membrane bioreactor (MBR) by Acinetobacter junii. After acclimation and enrichment in a sequencing batch reactor (SBR), Acinetobacter junii, a kind of denitrifying phosphate accumulating organism (DPAO), was successfully screened in the used SBR. Then it was verified to be capable of effectively enhancing the performance in the simultaneous removal of nitrogen and phosphorus of AGS-MBR. In the system, DPAO (Acinetobacter junii) mainly occurred in AGS, and the highest ratio even reached 22.8%, but its competitive advantages highly depend on the size of AGS. The presented results can cultivate AGS and enrich DPAO simultaneously to improve the removal of nitrogen and phosphorus of an AGS-MBR, which provide an environmentally friendly approach to upgrade traditional wastewater treatment processes.
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Affiliation(s)
- Weifeng Liang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Biao Yang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Liying Bin
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yadong Hu
- Bio-Form Biotechnology (Guangdong) Co., Ltd., Foshan, 528000, PR China
| | - Depeng Fan
- Bio-Form Biotechnology (Guangdong) Co., Ltd., Foshan, 528000, PR China
| | - Weirui Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Ping Li
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
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Hasan SF, Abo Elsoud MM, Sidkey NM, Elhateir MM. Production and characterization of polyhydroxybutyrate bioplastic precursor from Parageobacillus toebii using low-cost substrates and its potential antiviral activity. Int J Biol Macromol 2024; 262:129915. [PMID: 38325682 DOI: 10.1016/j.ijbiomac.2024.129915] [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: 11/14/2023] [Revised: 01/26/2024] [Accepted: 01/31/2024] [Indexed: 02/09/2024]
Abstract
There is an increasing desire for bioplastics produced from renewable resources as an alternative to their petrochemical counterparts. These biopolymers have long-unnoticed antiviral properties. This study aimed to produce and characterize bioplastics by Parageobacillus toebii using low-cost substrates and determine their antiviral activity against coxsackievirus B4. Seven low-cost substrates (bagasse, water hyacinth, rice straw, rice water, sesame husks, molasses, and corn syrup) were compared with glucose for bioplastic precursor production. The highest bioplastic produced was from water hyacinth and glucose, followed by molasses, rice straw, rice water, sesame husks, and bagasse. Water hyacinth and glucose media were further optimized to increase the bioplastic precursor yield. The optimization of the media leads to increases in bioplastic precursor yields of 1.8-fold (3.456 g/L) and 1.496-fold (2.768 g/L), respectively. These bioplastics were further characterized by thermogravimetric analysis (TGA), Fourier-transformed infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR), and gas chromatography-mass spectrometry (GC-MS). They are thermostable, and their characterizations confirm the presence of polyhydroxybutyrate. The antiviral assay showed reasonable antiviral effects for bioplastics from water hyacinth (80.33 %) and glucose (55.47 %) media at 250 μg/mL maximum non-toxic concentrations (MNTC). The present investigation demonstrates a low-cost model for producing polyhydroxybutyrate bioplastic precursor for antiviral applications.
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Affiliation(s)
- Seham F Hasan
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University (Girls Branch), Yossuf Abbas St., P.O. 11754, Nasr City, Cairo, Egypt.
| | - Mostafa M Abo Elsoud
- Microbial Biotechnology Department, National Research Centre, 33 El-Buhouth St., Dokki, P.O. 12622, Giza, Egypt
| | - Nagwa M Sidkey
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University (Girls Branch), Yossuf Abbas St., P.O. 11754, Nasr City, Cairo, Egypt
| | - Mai M Elhateir
- Botany and Microbiology Department, Faculty of Science, Al-Azhar University (Girls Branch), Yossuf Abbas St., P.O. 11754, Nasr City, Cairo, Egypt
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Amer A, Kim Y. Modeling the growth of diverse microorganisms during feast-famine enrichment. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10803. [PMID: 36332660 DOI: 10.1002/wer.10803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/30/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
Polyhydroxyalkanoates (PHAs) are biodegradable polymers that can decrease the severe environmental pollution of petroleum plastics. PHA production by mixed microbial communities has been extensively studied to lower the high PHA prices. However, the competition between distinct microbial communities during the enrichment of PHA accumulators in mixed cultures has not been widely investigated. Thus, in this work, we developed a mathematical model for the competition between PHA accumulators and non-PHA accumulators in the feast-famine enrichment strategy. The developed model successfully simulated published lab-scale experimental data for Plasticicumulans acidivorans, a well-studied PHA accumulator that can store PHA up to 90% of the cell weight. The growth kinetics for both PHA and non-PHA accumulators were estimated and compared to the values in the literature. The uncertainties in the model kinetics were studied by expanding the model to include additional sub-biomass components for each heterotrophic group. As a result, the microbial diversity of microbial communities was observed to influence the enrichment of PHA accumulators in mixed cultures. Additionally, the calibrated model was applied to investigate the cultivation conditions, such as cycle lengths, carbon-to-nitrogen ratio, and solids retention time for successful P. acidivorans enrichment in mixed cultures. The developed model can be applied to control the cultivation and enrichment of PHA accumulators in large-scale PHA production systems. PRACTITIONER POINTS: A new model for the enrichment of PHA accumulators was developed. The model can simulate PHA accumulation by enriched cultures. The model was calibrated and validated for Plasticicumulans acidivorans. The impact of microbial diversity on enriching PHA accumulators was investigated. Short cycles (<12 h) and SRT (<10 d) are suggested for successful enrichment.
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Affiliation(s)
- Abdelrahman Amer
- Department of Civil Engineering, McMaster University, Hamilton, Canada
- Civil Engineering Department, Menoufia University, Shebin ElKom, Egypt
| | - Younggy Kim
- Department of Civil Engineering, McMaster University, Hamilton, Canada
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Cao JS, Xu RZ, Luo JY, Feng Q, Fang F. Rapid quantification of intracellular polyhydroxyalkanoates via fluorescence techniques: A critical review. BIORESOURCE TECHNOLOGY 2022; 350:126906. [PMID: 35227918 DOI: 10.1016/j.biortech.2022.126906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/14/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
Polyhydroxyalkanoates (PHA) are promising bioplastics with excellent physicochemical properties and biodegradability, whereas PHA products suffer from high manufacturing costs. To reduce costs of PHA production, experiments with mixed microbial cultures and low-cost substrates have been conducted widely, where rapid and robust PHA quantification methods are necessary. Compared with traditional gas chromatography methods, PHA fluorescence quantification (PHA-FQ) methods may be quicker, safer and more suitable for modern experiments with high throughput requirements. However, practical applications of PHA-FQ methods are still limited. Therefore, this review provides a comprehensive understanding of PHA-FQ methods. Performance of PHA-staining fluorochromes, relevant spectral properties, and important staining procedures are summarized. Current developments of PHA-FQ protocols are critically reviewed. Main considerations needed to make PHA-FQ protocol reliable are comprehensively discussed. Finally, potential improvements in various aspects of PHA-FQ methods are highlighted. This review could help researchers develop more effective PHA-FQ methods and facilitate future experiments related to PHA.
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Affiliation(s)
- Jia-Shun Cao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Run-Ze Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Jing-Yang Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Qian Feng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Fang Fang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China.
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Mal N, Satpati G, Raghunathan S, Davoodbasha M. Current strategies on algae-based biopolymer production and scale-up. CHEMOSPHERE 2022; 289:133178. [PMID: 34890607 DOI: 10.1016/j.chemosphere.2021.133178] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/15/2021] [Accepted: 12/02/2021] [Indexed: 06/13/2023]
Abstract
The craving for an alternative to the existing plastic products gives rise to the concept of algae-based bioplastic production, which appears to be excellently biodegradable and cost-effective. The significant assortment of algal biopolymers draws great attention to stop the surge of plastic waste and to mitigate the burning problems of environmental pollution. The polyhydroxyalkanoates (PHA) are naturally-occurring biopolymers found in the form of esters accumulated within a number of microbes, which provides the pillar for several biomolecules. This review summarizes the global scenario as well as the precise technique of algae-based PHA extraction and bioplastic production. In addition, different techniques for valorisation of PHA production, its biodegradability and its commercial applications are also taken into consideration.
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Affiliation(s)
- Navonil Mal
- Department of Botany, University of Calcutta, Kolkata, 700019, West Bengal, India
| | - GourGopal Satpati
- Department of Botany, Bangabasi Evening College, University of Calcutta, Kolkata, 700009, West Bengal, India.
| | - Sathya Raghunathan
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India.
| | - MubarakAli Davoodbasha
- School of Life Sciences, B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India; Centre for Micro Algal and Nano Biotechnology (CeMANT), Crescent Innovation and Incubation Council (CIIC), B.S. Abdur Rahman Crescent Institute of Science and Technology, Chennai, India; Division of Bioengineering, Incheon National University, Republic of Korea.
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Xu RZ, Cao JS, Luo JY, Feng Q, Ni BJ, Fang F. Integrating mechanistic and deep learning models for accurately predicting the enrichment of polyhydroxyalkanoates accumulating bacteria in mixed microbial cultures. BIORESOURCE TECHNOLOGY 2022; 344:126276. [PMID: 34742815 DOI: 10.1016/j.biortech.2021.126276] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 06/13/2023]
Abstract
The enrichment of polyhydroxyalkanoates (PHA) accumulating bacteria (PAB) in mixed microbial cultures (MMC) is extremely difficult to be predicted and optimized. Here we demonstrate that mechanistic and deep learning models can be integrated innovatively to accurately predict the dynamic enrichment of PAB. Well-calibrated activated sludge models (ASM) of the PAB enrichment process provide time-dependent data under different operating conditions. Recurrent neural network (RNN) models are trained and tested based on the time-dependent dataset generated by ASM. The accurate prediction performance is achieved (R2 > 0.991) for three different PAB enrichment datasets by the optimized RNN model. The optimized RNN model can also predict the equilibrium concentration of PAB (R2 = 0.944) and corresponding time, which represents the end of the PAB enrichment process. This study demonstrates the strength of integrating mechanistic and deep learning models to predict long-term variations of specific microbes, helping to optimize their selection process for PHA production.
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Affiliation(s)
- Run-Ze Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Jia-Shun Cao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Jing-Yang Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Qian Feng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater (CTWW), School of Civil and Environmental Engineering, University of Technology Sydney (UTS), Sydney, NSW 2007, Australia
| | - Fang Fang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China.
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Rao A, Haque S, El-Enshasy HA, Singh V, Mishra BN. RSM-GA Based Optimization of Bacterial PHA Production and In Silico Modulation of Citrate Synthase for Enhancing PHA Production. Biomolecules 2019; 9:biom9120872. [PMID: 31842491 PMCID: PMC6995514 DOI: 10.3390/biom9120872] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/27/2019] [Accepted: 12/02/2019] [Indexed: 12/23/2022] Open
Abstract
The inexhaustible nature and biodegradability of bioplastics like polyhydroxyalkanoates (PHAs) make them suitable assets to replace synthetic plastics. The eventual fate of these eco-friendly and non-toxic bioplastics relies upon the endeavors towards satisfying cost and, in addition, execution necessity. In this study, we utilized and statistically optimized different food (kitchen-/agro-) waste as a sole carbon/nitrogen source for the production of PHA at a reduced cost, indicating a proficient waste administration procedure. Seven different types of kitchen-/agro-waste were used as unique carbon source and four different types of nitrogen source were used to study their impact on PHA production by Bacillus subtilis MTCC 144. Among four different studied production media, mineral salt medium (MSM) (biomass: 37.7 g/L; cell dry weight: 1.8 g/L; and PHA: 1.54 g/L) was found most suitable for PHA production. Further, carbon and nitrogen components of MSM were optimized using one-factor-at-a-time experiments, and found that watermelon rind (PHA = 12.97 g/L) and pulse peel (PHA = 13.5 g/L) were the most suitable carbon and nitrogen sources, respectively, in terms of PHA (78.60%) recovery. The concentrations of these factors (sources) were statistically optimized using response surface methodology coupled with the genetic algorithm approach. Additionally, in order to enhance microbial PHA production, the interaction of citrate synthase, a key enzyme in the TCA cycle, with different known inhibitors was studied using in silico molecular docking approach. The inhibition of citrate synthase induces the blockage of the tricarboxylic cycle (TCA), thereby increasing the concentration of acetyl-CoA that helps in enhanced PHA production. Molecular docking of citrate synthase with different inhibitors of PubChem database revealed that hesperidin (PubChem compound CID ID 10621), generally present in citrus fruits, is the most efficient inhibitor of the TCA cycle with the binding score of –11.4 and warrants experimental validation. Overall, this study provides an efficient food waste management approach by reducing the production cost and enhancing the production of PHA, thereby lessening our reliance on petroleum-based plastics.
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Affiliation(s)
- Apoorva Rao
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan 45142, Saudi Arabia;
| | - Hesham A. El-Enshasy
- Institute of Bioproduct Development (IBD), Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru 81310, Malaysia;
- School of Chemical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru 81310, Malaysia
- City of Scientific Research and Technological Applications, New Burg Al Arab 21934, Alexandria, Egypt
| | - Vineeta Singh
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
- Correspondence: (V.S.); (B.N.M.); Tel.: +91-522-2361692 (V.S.); +91-522-2361631 (B.N.M.)
| | - Bhartendu Nath Mishra
- Department of Biotechnology, Institute of Engineering and Technology, Dr. A.P.J. Abdul Kalam Technical University, Lucknow, Sitapur Road, Lucknow 226021, Uttar Pradesh, India;
- Correspondence: (V.S.); (B.N.M.); Tel.: +91-522-2361692 (V.S.); +91-522-2361631 (B.N.M.)
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