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Aragno J, Fernandez-Valle P, Thiriet A, Grondin C, Legras JL, Camarasa C, Bloem A. Two-Stage Screening of Metschnikowia spp. Bioprotective Properties: From Grape Juice to Fermented Must by Saccharomyces cerevisiae. Microorganisms 2024; 12:1659. [PMID: 39203501 PMCID: PMC11356803 DOI: 10.3390/microorganisms12081659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Revised: 07/30/2024] [Accepted: 08/03/2024] [Indexed: 09/03/2024] Open
Abstract
Gluconobacter oxydans (Go) and Brettanomyces bruxellensis (Bb) are detrimental micro-organisms compromising wine quality through the production of acetic acid and undesirable aromas. Non-Saccharomyces yeasts, like Metschnikowia species, offer a bioprotective approach to control spoilage micro-organisms growth. Antagonist effects of forty-six Metschnikowia strains in a co-culture with Go or Bb in commercial grape juice were assessed. Three profiles were observed against Go: no effect, complete growth inhibition, and intermediate bioprotection. In contrast, Metschnikowia strains exhibited two profiles against Bb: no effect and moderate inhibition. These findings indicate a stronger antagonistic capacity against Go compared to Bb. Four promising Metschnikowia strains were selected and their bioprotective impact was investigated at lower temperatures in Chardonnay must. The antagonistic effect against Go was stronger at 16 °C compared to 20 °C, while no significant impact on Bb growth was observed. The bioprotection impact on Saccharomyces cerevisiae fermentation has been assessed. Metschnikowia strains' presence did not affect the fermentation time, but lowered the fermentation rate of S. cerevisiae. An analysis of central carbon metabolism and volatile organic compounds revealed a strain-dependent enhancement in the production of metabolites, including glycerol, acetate esters, medium-chain fatty acids, and ethyl esters. These findings suggest Metschnikowia species' potential for bioprotection in winemaking and wine quality through targeted strain selection.
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Affiliation(s)
- Julie Aragno
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
| | - Pascale Fernandez-Valle
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
| | - Angèle Thiriet
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
- Microbial Research Infrastructure, 4710-057 Braga, Portugal
| | - Cécile Grondin
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
- Microbial Research Infrastructure, 4710-057 Braga, Portugal
| | - Jean-Luc Legras
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
- Microbial Research Infrastructure, 4710-057 Braga, Portugal
| | - Carole Camarasa
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
| | - Audrey Bloem
- UMR SPO, INRAE, Institut Agro, Université Montpellier, 34060 Montpellier, France; (J.A.); (C.G.); (J.-L.L.); (C.C.)
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Shangpliang HNJ, Tamang JP. Metagenomics and metagenome-assembled genomes mining of health benefits in jalebi batter, a naturally fermented cereal-based food of India. Food Res Int 2023; 172:113130. [PMID: 37689895 DOI: 10.1016/j.foodres.2023.113130] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 06/08/2023] [Accepted: 06/09/2023] [Indexed: 09/11/2023]
Abstract
Jalebi is one of the oldest Indian traditional fermented wheat-based confectioneries. Since jalebi is prepared by natural fermentation, diverse microbial community is expected to play bio-functional activities. Due to limited studies, information on microbial community structure in jalebi is unknown. Hence, the present study is aimed to profile the microbial community in jalebi by shotgun metagenomics and also to predict putative probiotic and functional genes by metagenome-assembled genome (MAG). Bacteria were the most abundant domain (91.91%) under which Bacillota was the most abundant phylum (82%). The most abundant species was Lapidilactobacillus dextrinicus followed by several species of lactic acid bacteria, acetic acid bacteria including few yeasts. Lap. dextrinicus was also significantly abundant in jalebi when compared to similar fermented wheat-based sourdough. Additionally, Lap. bayanensis, Pediococcus stilesii, and yeast- Candida glabrata, Gluconobacter japonicus, Pichia kudriavzevii, Wickerhamomyces anomalus were only detected in jalebi, which are not detected in sourdough. Few viruses and archaea were detected with < 1 % abundance. In silico screening of genes from the abundant species was mined using both KEGG and EggNOG database for putative health beneficial attributes. Circular genomes of five high-quality MAGs, identified as Lapidilactobacillus dextrinicus, Enterococcus hirae, Pediococcus stilesii, Acetobacter indonesiensis and Acetobacter cibinongensis, were constructed separately and putative genes were mapped and annotated. The CRISPR/Cas gene clusters in the genomes of four MAGs except Acetobacter cibinongensis were detected. MAGs also showed several secondary metabolites. Since, the identified MAGs have different putative genes for bio-functional properties, this may pave the way to selectively culture the uncultivated putative microbes for jalebi production. We believe this is the first report on metagenomic and MAGs of jalebi.
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Affiliation(s)
| | - Jyoti Prakash Tamang
- Department of Microbiology, School of Life Sciences, Sikkim University, Tadong, Gangtok 737102, Sikkim, India.
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New perspectives into Gluconobacter-catalysed biotransformations. Biotechnol Adv 2023; 65:108127. [PMID: 36924811 DOI: 10.1016/j.biotechadv.2023.108127] [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: 10/22/2022] [Revised: 03/02/2023] [Accepted: 03/08/2023] [Indexed: 03/17/2023]
Abstract
Different from other aerobic microorganisms that oxidise carbon sources to water and carbon dioxide, Gluconobacter catalyses the incomplete oxidation of various substrates with regio- and stereoselectivity. This ability, as well as its capacity to release the resulting products into the reaction media, place Gluconobacter as a privileged member of a non-model microorganism class that may boost industrial biotechnology. Knowledge of new technologies applied to Gluconobacter has been piling up in recent years. Advancements in its genetic modification, application of immobilisation tools and careful designs of the transformations, have improved productivities and stabilities of Gluconobacter strains or enabled new bioconversions for the production of valuable marketable chemicals. In this work, the latest advancements applied to Gluconobacter-catalysed biotransformations are summarised with a special focus on recent available tools to improve them. From genetic and metabolic engineering to bioreactor design, the most recent works on the topic are analysed in depth to provide a comprehensive resource not only for scientists and technologists working on/with Gluconobacter, but for the general biotechnologist.
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Thakur M, Modi VK. Biocolorants in food: Sources, extraction, applications and future prospects. Crit Rev Food Sci Nutr 2022; 64:4674-4713. [PMID: 36503345 DOI: 10.1080/10408398.2022.2144997] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Color of a food is one of the major factors influencing its acceptance by consumers. At presently synthetic dyes are the most commonly used food colorant in food industry by providing more esthetically appearance and as a means to quality control. However, the growing concern about health and environmental due to associated toxicity with synthetic food colorants has accelerated the global efforts to replace them with safer and healthy food colorants obtained from natural resources (plants, microorganisms, and animals). Further, many of these biocolorants not only provide myriad of colors to the food but also exert biological properties, thus they can be used as nutraceuticals in foods and beverages. In order to understand the importance of nature-derived pigments as food colorants, this review provides a thorough discussion on the natural origin of food colorants. Following this, different extraction methods for isolating biocolorants from plants and microbes were also discussed. Many of these biocolorants not only provide color, but also have many health promoting properties, for this reason their physicochemical and biological properties were also reviewed. Finally, current trends on the use of biocolorants in foods, and the challenges faced by the biocolorants in their effective utilization by food industry and possible solutions to these challenges were discussed.
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Affiliation(s)
- Monika Thakur
- Amity Institute of Food Technology, Amity University, Noida, Uttar Pradesh, India
| | - V K Modi
- Amity Institute of Food Technology, Amity University, Noida, Uttar Pradesh, India
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Characterization of Physicochemical Properties of Melanin Produced by Gluconobacter oxydans FBFS 97. FERMENTATION 2022. [DOI: 10.3390/fermentation8110574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The present study aimed to characterize melanin pigment extracted from Gluconobacter oxydans FBFS 97. After 14 days of culture at 28 °C in GY (glucose and yeast extract) liquid-state medium, G. oxydans FBFS97 produce the maximum melanin, up to about 12–15 mg/L. The physicochemical characteristics of the extracted melanin showed an ability to dissolve in 1 mol/L NaOH or 1 mol/L KOH, and insolubility in water and most organic solvents, such as chloroform and petroleum ether. The extracted melanin was confirmed to be exact melanin by ultraviolet-visible spectrophotometry, Fourier-transform infrared spectroscopy, thin-layer chromatography, elemental analysis, and scanning electron microscopy. The UV-visible spectrum of G. oxydans FBFS97 exhibited a maximum absorption peak at 230 nm. Extracted melanin demonstrated significant free radical-scavenging activity by DPPH and ABTS methods. The IC50 value of the extracted melanin for scavenging 50% DPPH radicals was 36.94 μg/mL, and the IC50 value of antioxidant activity for ABTS was 4.06 μg/mL. Hence, G. oxydans FBFS97 has the potential to be a new candidate for melanin production.
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Tarasov S, Plekhanova Y, Kashin V, Gotovtsev P, Signore MA, Francioso L, Kolesov V, Reshetilov A. Gluconobacter Oxydans-Based MFC with PEDOT:PSS/Graphene/Nafion Bioanode for Wastewater Treatment. BIOSENSORS 2022; 12:bios12090699. [PMID: 36140084 PMCID: PMC9496339 DOI: 10.3390/bios12090699] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/23/2022] [Accepted: 08/28/2022] [Indexed: 11/16/2022]
Abstract
Microbial fuel cells (MFCs) are a variety of bioelectrocatalytic devices that utilize the metabolism of microorganisms to generate electric energy from organic matter. This study investigates the possibility of using a novel PEDOT:PSS/graphene/Nafion composite in combination with acetic acid bacteria Gluconobacter oxydans to create a pure culture MFC capable of effective municipal wastewater treatment. The developed MFC was shown to maintain its activity for at least three weeks. The level of COD in municipal wastewater treatment was reduced by 32%; the generated power was up to 81 mW/m2 with a Coulomb efficiency of 40%. Combining the MFC with a DC/DC boost converter increased the voltage generated by two series-connected MFCs from 0.55 mV to 3.2 V. A maximum efficiency was achieved on day 8 of MFC operation and was maintained for a week; capacitors of 6800 µF capacity were fully charged in ~7 min. Thus, G. oxydans cells can become an important part of microbial consortia in MFCs used for treatment of wastewaters with reduced pH.
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Affiliation(s)
- Sergei Tarasov
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Center for Biological Research of the Russian Academy of Sciences, Moscow Region, 142290 Pushchino, Russia
- Correspondence:
| | - Yulia Plekhanova
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Center for Biological Research of the Russian Academy of Sciences, Moscow Region, 142290 Pushchino, Russia
| | - Vadim Kashin
- FSBIS V.A. Kotelnikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 125009 Moscow, Russia
| | - Pavel Gotovtsev
- Biotechnology and Bioenergy Department, National Research Centre “Kurchatov Institute”, 123182 Moscow, Russia
- Moscow Institute of Physics and Technology (National Research University), Moscow Region, 141701 Dolgoprudny, Russia
| | - Maria Assunta Signore
- CNR IMM, Institute for Microelectronics and Microsystems, Via Monteroni, I-73100 Lecce, Italy
| | - Luca Francioso
- CNR IMM, Institute for Microelectronics and Microsystems, Via Monteroni, I-73100 Lecce, Italy
| | - Vladimir Kolesov
- FSBIS V.A. Kotelnikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 125009 Moscow, Russia
| | - Anatoly Reshetilov
- G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Center for Biological Research of the Russian Academy of Sciences, Moscow Region, 142290 Pushchino, Russia
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Zhang H, You C. 16S ribosomal RNA-depletion PCR and its application in cause analysis of yogurt package shrinkage. J Dairy Sci 2022; 105:7288-7297. [PMID: 35931476 DOI: 10.3168/jds.2021-21575] [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: 11/18/2021] [Accepted: 05/12/2022] [Indexed: 11/19/2022]
Abstract
Fermentative bacteria, the main microbiota in yogurt, interfere with the detection of unintended bacterial contaminants. The removal of fermentative bacteria and enrichment of unintended bacterial contaminants is a challenging task in bacterial detection. The present study developed a new 16S rRNA-depletion PCR for such enrichment and detection. Specifically, a single-guide RNA was designed and synthesized based on the 16S rRNA sequence of Streptococcus thermophilus, with the highest DNA abundance in the yogurt. The CRISPR-Cas9 system was used to specifically cleave and remove the genomic DNA of the fermentative bacteria, followed by PCR amplification. This method improved the detection sensitivity, simplified the operation steps, and reduced the detection cost of PCR analysis. We also used the 16S rRNA-depletion PCR to amplify and detect the unintended bacterial contaminants in yogurts with shrunken packages and analyzed the underlying reasons to prevent this issue of product quality.
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Affiliation(s)
- Hongfa Zhang
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Centre of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co. Ltd., Synergetic Innovation Centre of Food Safety and Nutrition, Shanghai 200436, China.
| | - Chunping You
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Centre of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co. Ltd., Synergetic Innovation Centre of Food Safety and Nutrition, Shanghai 200436, China
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Harirchi S, Wainaina S, Sar T, Nojoumi SA, Parchami M, Parchami M, Varjani S, Khanal SK, Wong J, Awasthi MK, Taherzadeh MJ. Microbiological insights into anaerobic digestion for biogas, hydrogen or volatile fatty acids (VFAs): a review. Bioengineered 2022; 13:6521-6557. [PMID: 35212604 PMCID: PMC8973982 DOI: 10.1080/21655979.2022.2035986] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/20/2021] [Accepted: 01/17/2022] [Indexed: 11/02/2022] Open
Abstract
In the past decades, considerable attention has been directed toward anaerobic digestion (AD), which is an effective biological process for converting diverse organic wastes into biogas, volatile fatty acids (VFAs), biohydrogen, etc. The microbial bioprocessing takes part during AD is of substantial significance, and one of the crucial approaches for the deep and adequate understanding and manipulating it toward different products is process microbiology. Due to highly complexity of AD microbiome, it is critically important to study the involved microorganisms in AD. In recent years, in addition to traditional methods, novel molecular techniques and meta-omics approaches have been developed which provide accurate details about microbial communities involved AD. Better understanding of process microbiomes could guide us in identifying and controlling various factors in both improving the AD process and diverting metabolic pathway toward production of selective bio-products. This review covers various platforms of AD process that results in different final products from microbiological point of view. The review also highlights distinctive interactions occurring among microbial communities. Furthermore, assessment of these communities existing in the anaerobic digesters is discussed to provide more insights into their structure, dynamics, and metabolic pathways. Moreover, the important factors affecting microbial communities in each platform of AD are highlighted. Finally, the review provides some recent applications of AD for the production of novel bio-products and deals with challenges and future perspectives of AD.
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Affiliation(s)
- Sharareh Harirchi
- Swedish Centre for Resource Recovery, University of Borås, 50190Borås, Sweden
| | - Steven Wainaina
- Swedish Centre for Resource Recovery, University of Borås, 50190Borås, Sweden
| | - Taner Sar
- Swedish Centre for Resource Recovery, University of Borås, 50190Borås, Sweden
| | - Seyed Ali Nojoumi
- Microbiology Research Center, Pasteur Institute of Iran, Tehran, Iran
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Milad Parchami
- Swedish Centre for Resource Recovery, University of Borås, 50190Borås, Sweden
| | - Mohsen Parchami
- Swedish Centre for Resource Recovery, University of Borås, 50190Borås, Sweden
| | - Sunita Varjani
- Paryavaran Bhavan, Gujarat Pollution Control Board, Gandhinagar, Gujarat, India
| | - Samir Kumar Khanal
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii, USA
| | - Jonathan Wong
- Department of Biology, Institute of Bioresource and Agriculture and, Hong Kong Baptist University, Hong Kong
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Taicheng Road 3#, Yangling, Shaanxi, 712100, China
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Mechanical properties of cellulose nanofibril papers and their bionanocomposites: A review. Carbohydr Polym 2021; 273:118507. [PMID: 34560938 DOI: 10.1016/j.carbpol.2021.118507] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/14/2021] [Accepted: 07/26/2021] [Indexed: 12/25/2022]
Abstract
Cellulose nanofibril (CNF) paper has various applications due to its unique advantages. Herein, we present the intrinsic mechanical properties of CNF papers, along with the preparation and properties of nanoparticle-reinforced CNF composite papers. The literature on CNF papers reveals a strong correlation between the intrafibrillar network structure and the resulting mechanical properties. This correlation is found to hold for all primary factors affecting mechanical properties, indicating that the performance of CNF materials depends directly on and can be tailored by controlling the intrafibrillar network of the system. The parameters that influence the mechanical properties of CNF papers were critically reviewed. Moreover, the effect on the mechanical properties by adding nanofillers to CNF papers to produce multifunctional composite products was discussed. We concluded this article with future perspectives and possible developments in CNFs and their bionanocomposite papers.
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Liu S, Hu W, Wang Z, Chen T. Rational Engineering of Escherichia coli for High-Level Production of Riboflavin. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:12241-12249. [PMID: 34623820 DOI: 10.1021/acs.jafc.1c04471] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Riboflavin is widely used as a food additive. Here, multiple strategies were used to increase riboflavin production in Escherichia coli LS31T. First, purR deletion and co-overexpression of fbp, purF, prs, gmk, and ndk genes resulted in an increase of 18.6% in riboflavin titer (reaching 729.7 mg/L). Second, optimization of reduced nicotinamide adenine dinucleotide phosphate/nicotinamide adenine dinucleotide ratio and respiratory chain activity in LS31T increased the titer up to 1020.2 mg/L. Third, the expression level of the guaC gene in LS31T was downregulated by ribosome binding site replacement, and the riboflavin production was increased by 10.6% to 658.5 mg/L. Then, all the favorable modifications were integrated together, and the resulting strain LS72T produced 1339 mg/L of riboflavin. Moreover, the riboflavin titer of LS72T reached 21 g/L in fed-batch cultivation, with a yield of 110 mg riboflavin/g glucose. To our knowledge, both the riboflavin titer and yield obtained in fed-batch fermentation are the highest ones among all the rationally engineered strains.
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Affiliation(s)
- Shuang Liu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin 300072, China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Wenya Hu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin 300072, China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Zhiwen Wang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin 300072, China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
| | - Tao Chen
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin 300072, China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China
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Metagenome-Assembled Genomes Contribute to Unraveling of the Microbiome of Cocoa Fermentation. Appl Environ Microbiol 2021; 87:e0058421. [PMID: 34105982 DOI: 10.1128/aem.00584-21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Metagenomic studies about cocoa fermentation have mainly reported on the analysis of short reads for determination of operational taxonomic units. However, it is also important to determine metagenome-assembled genomes (MAGs), which are genomes deriving from the assembly of metagenomics. For this research, all the cocoa metagenomes from public databases were downloaded, resulting in five data sets: one from Ghana and four from Brazil. In addition, in silico approaches were used to describe putative phenotypes and the metabolic potential of MAGs. A total of 17 high-quality MAGs were recovered from these microbiomes, as follows: (i) for fungi, Yamadazyma tenuis (n = 1); (ii) lactic acid bacteria, Limosilactobacillus fermentum (n = 5), Liquorilactobacillus cacaonum (n = 1), Liquorilactobacillus nagelli (n = 1), Leuconostoc pseudomesenteroides (n = 1), and Lactiplantibacillus plantarum subsp. plantarum (n = 1); (iii) acetic acid bacteria, Acetobacter senegalensis (n = 2) and Kozakia baliensis (n = 1); and (iv) Bacillus subtilis (n = 1), Brevundimonas sp. (n = 2), and Pseudomonas sp. (n = 1). Medium-quality MAGs were also recovered from cocoa microbiomes, including some that, to our knowledge, were not previously detected in this environment (Liquorilactobacillus vini, Komagataeibacter saccharivorans, and Komagataeibacter maltaceti) and others previously described (Fructobacillus pseudoficulneus and Acetobacter pasteurianus). Taken together, the MAGs were useful for providing an additional description of the microbiome of cocoa fermentation, revealing previously overlooked microorganisms, with prediction of key phenotypes and biochemical pathways. IMPORTANCE The production of chocolate starts with the harvesting of cocoa fruits and the spontaneous fermentation of the seeds in a microbial succession that depends on yeasts, lactic acid bacteria, and acetic acid bacteria in order to eliminate bitter and astringent compounds present in the raw material, which will be further roasted and grinded to originate the cocoa powder that will enter the food processing industry. The microbiota of cocoa fermentation is not completely known, and yet it advanced from culture-based studies to the advent of next-generation DNA sequencing, with the generation of a myriad of data that need bioinformatic approaches to be properly analyzed. Although the majority of metagenomic studies have been based on short reads (operational taxonomic units), it is also important to analyze entire genomes to determine more precisely possible ecological roles of different species. Metagenome-assembled genomes (MAGs) are very useful for this purpose; here, MAGs from cocoa fermentation microbiomes are described, and the possible implications of their phenotypic and metabolic potentials are discussed.
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Probiotic Potential of a Novel Vitamin B2-Overproducing Lactobacillus plantarum Strain, HY7715, Isolated from Kimchi. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11135765] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Vitamin B2, also known as riboflavin, is essential for maintaining human health. The purpose of this study was to isolate novel lactic acid bacteria that overproduce vitamin B2 and to validate their potential as probiotics. In this study, Lactobacillus plantarum HY7715 (HY7715) was selected among lactic acid bacteria isolated from Kimchi. HY7715 showed a very high riboflavin-producing ability compared to the control strain due to the high expression of ribA, ribB, ribC, ribH, and ribG genes. HY7715 produced 34.5 ± 2.41 mg/L of riboflavin for 24 h without consuming riboflavin in the medium under optimal growth conditions. It was able to produce riboflavin in an in vitro model of the intestinal environment. In addition, when riboflavin deficiency was induced in mice through nutritional restriction, higher levels of riboflavin were detected in plasma and urine in the HY7715 administration group than in the control group. HY7715 showed high survival rate in simulated gastrointestinal conditions and had antibiotic resistance below the cutoff MIC value suggested by the European Food Safety Authority; moreover, it did not cause hemolysis. In conclusion, HY7715 could be considered a beneficial probiotic strain for human and animal applications, suggesting that it could be a new alternative to address riboflavin deficiency.
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Yuan X, Chen X, Virk MS, Ma Y, Chen F. Effects of Various Rice-Based Raw Materials on Enhancement of Volatile Aromatic Compounds in Monascus Vinegar. Molecules 2021; 26:687. [PMID: 33525711 PMCID: PMC7866154 DOI: 10.3390/molecules26030687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 11/16/2022] Open
Abstract
Monascus vinegar (MV), during whose brewing process Monascus spp. and polished rice (PR) are normally used as the starter and the raw material, respectively, is one of the traditional vinegars in China. In this study, the effects of three raw materials, including PR, unhusked rice (UR), and germinated UR (GR), on MV volatile compounds have been investigated. The results revealed that MV of GR (GMV), and its intermediate Monascus wine (GMW), exhibited the highest amount of aroma, not only in the concentrations but also in the varieties of the aromatic compounds mainly contributing to the final fragrance. Especially after three years of aging, the contents of benzaldehyde and furfural in GMV could reach to 13.93% and 0.57%, respectively, both of which can coordinate synergistically on enhancing the aroma. We also found that the filtering efficiency was significantly improved when UR and GR were applied as the raw materials, respectively. Therefore, GR might be more suitable raw materials for MV.
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Affiliation(s)
- Xi Yuan
- Hubei International Scientific and Technological Cooperation Base of Traditional Fermented Foods, Huazhong Agricultural University, Wuhan 430070, China; (X.Y.); (M.S.V.)
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaoyuan Chen
- Nutrition & Health Research Institute, COFCO Corporation, Beijing 102209, China;
| | - Muhammad Safiullah Virk
- Hubei International Scientific and Technological Cooperation Base of Traditional Fermented Foods, Huazhong Agricultural University, Wuhan 430070, China; (X.Y.); (M.S.V.)
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yinglun Ma
- Fujian Yongchun Ageing Vinegar Vinegar Industry Co., Ltd., Quanzhou 362000, China;
| | - Fusheng Chen
- Hubei International Scientific and Technological Cooperation Base of Traditional Fermented Foods, Huazhong Agricultural University, Wuhan 430070, China; (X.Y.); (M.S.V.)
- College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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