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Sun K, Tang M, Li S, Tong S. Mildew detection in rice grains based on computer vision and the YOLO convolutional neural network. Food Sci Nutr 2024; 12:860-868. [PMID: 38370089 PMCID: PMC10867476 DOI: 10.1002/fsn3.3798] [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: 08/01/2023] [Revised: 10/14/2023] [Accepted: 10/18/2023] [Indexed: 02/20/2024] Open
Abstract
At present, detection methods for rice microbial indicators are usually based on microbial culture or sensory detection methods, which are time-consuming or require expertise and thus cannot meet the needs of on-site rice testing when the rice is taken out of storage or traded. In order to develop a fast and non-destructive method for detecting rice mildew, in this paper, micro-computer vision technology is used to collect images of mildewed rice samples from 9 image locations. Then, a YOLO-V5 convolutional neural network model is used to detect moldy areas of rice, and the mold coverage area is estimated. The relationship between the moldy areas and the total number of bacterial colonies in the image is obtained. The results show that the precision and the recall of the established YOLO-v5 model in identifying the mildewed areas of rice in the validation set were 82.1% and 86.5%, respectively. Based on the mean mildewed area identified by the YOLO-v5 model, the precision and recall for light mold detection were 100% and 95.3%, respectively. The proposed method based on micro-computer vision and the YOLO convolutional neural network can be applied to the rapid detection of mildew in rice taken out of storage or traded.
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Affiliation(s)
- Ke Sun
- College of Life SciencesAnhui Normal UniversityWuhuChina
| | - Mengdi Tang
- College of Life SciencesAnhui Normal UniversityWuhuChina
| | - Shu Li
- College of Life SciencesAnhui Normal UniversityWuhuChina
| | - Siyuan Tong
- College of Life SciencesAnhui Normal UniversityWuhuChina
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Tambong JT, Xu R, Chi SI, Birugu I, Bachelet S, Hutter C, Duceppe MO, Brière S. Pseudomonas quebecensis sp. nov., a bacterium isolated from root-zone soil of a native legume, Amphicarpaea bracteata (L.) Fernald, in Quebec, Canada. Int J Syst Evol Microbiol 2023; 73. [PMID: 37326615 DOI: 10.1099/ijsem.0.005890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023] Open
Abstract
Four bacterial strains (S1Bt3, S1Bt7, S1Bt30 and S1Bt42T) isolated from soil collected from the rhizosphere of a native legume, Amphicarpaea bracteata, were investigated using a polyphasic approach. Colonies were fluorescent, white-yellowish, circular and convex with regular margins on King's B medium. Cells were Gram-reaction-negative, aerobic, non-spore-forming rods. Oxidase- and catalase-positive. The optimal growth temperature of the strains was 37 °C. Phylogenetic analysis of the 16S rRNA gene sequences placed the strains within the genus Pseudomonas. Analysis of the 16S rRNA-rpoD-gyrB concatenated sequences clustered the strains and well separated from Pseudomonas rhodesiae CIP 104664T and Pseudomonas grimontii CFM 97-514T with the type strains of the closest species. Phylogenomic analysis of 92 up-to-date bacterial core gene and matrix-assisted laser desorption/ionization-time-of-flight MS biotyper data confirmed the distinct clustering pattern of these four strains. Digital DNA-DNA hybridization (41.7 %-31.2 %) and average nucleotide identity (91.1 %-87.0 %) values relative to closest validly published Pseudomonas species were below the species delineation thresholds of 70 and 96 %, respectively. Fatty acid composition results validated the taxonomic position of the novel strains in the genus Pseudomonas. Phenotypic characteristics from carbon utilization tests differentiated the novel strains from closely related Pseudomonas species. In silico prediction of secondary metabolite biosynthesis gene clusters in the whole-genome sequences of the four strains revealed the presence of 11 clusters involved in the production of siderophore, redox-cofactor, betalactone, terpene, arylpolyene and nonribosomal peptides. Based on phenotypic and genotypic data, strains S1Bt3, S1Bt7, S1Bt30 and S1Bt42T represent a novel species for which the name Pseudomonas quebecensis sp. nov. is proposed. The type strain is S1Bt42T (=DOAB 746T=LMG 32141T=CECT 30251T). The genomic DNA G+C content is 60.95 mol%.
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Affiliation(s)
- James T Tambong
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
- Department of Plant Science, University of Manitoba, Winnipeg, MB, Canada
| | - Renlin Xu
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
| | - Sylvia I Chi
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
- Canadian Blood Services, Ottawa, Ontario, Canada
| | - Isabelle Birugu
- Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON, Canada
| | - Sylvia Bachelet
- Ottawa Plant Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Conrad Hutter
- Ottawa Plant Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Marc-Olivier Duceppe
- Ottawa Plant Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Stephan Brière
- Ottawa Plant Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
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Grahovac J, Pajčin I, Vlajkov V. Bacillus VOCs in the Context of Biological Control. Antibiotics (Basel) 2023; 12:antibiotics12030581. [PMID: 36978448 PMCID: PMC10044676 DOI: 10.3390/antibiotics12030581] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 03/17/2023] Open
Abstract
A contemporary agricultural production system relying on heavy usage of agrochemicals represents a questionable outlook for sustainable food supply in the future. The visible negative environmental impacts and unforeseen consequences to human and animal health have been requiring a shift towards the novel eco-friendly alternatives for chemical pesticides for a while now. Microbial-based biocontrol agents have shown a promising potential for plant disease management. The bacteria of the genus Bacillus have been among the most exploited microbial active components due to several highly efficient mechanisms of action against plant pathogens, as well as a palette of additional plant-beneficial mechanisms, together with their suitable properties for microbial biopesticide formulations. Among other bioactive metabolites, volatile organic compounds (VOCs) have been investigated for their biocontrol applications, exhibiting the main advantage of long-distance effect without the necessity for direct contact with plants or pathogens. The aim of this study is to give an overview of the state-of-the-art in the field of Bacillus-based VOCs, especially in terms of their antibacterial, antifungal, and nematicidal action as the main segments determining their potential for biocontrol applications in sustainable agriculture.
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Antagonistic Activity of Volatile Organic Compounds Produced by Acid-Tolerant Pseudomonas protegens CLP-6 as Biological Fumigants To Control Tobacco Bacterial Wilt Caused by Ralstonia solanacearum. Appl Environ Microbiol 2023; 89:e0189222. [PMID: 36722969 PMCID: PMC9972909 DOI: 10.1128/aem.01892-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Tobacco bacterial wilt, which is caused by Ralstonia solanacearum, is a devastating soilborne disease of tobacco worldwide and is widespread in the continuously acidic fields of southern China. Here, the fumigation activity under different pH conditions, component identification, and bioactivity of the volatile organic compounds (VOCs) produced by an acid-tolerant strain, Pseudomonas protegens CLP-6, were investigated. There was a wide antimicrobial spectrum of the VOCs against phytopathogens, including four bacteria, eight fungi, and two oomycetes. The antagonistic activity of the VOCs against R. solanacearum was proportionally correlated with the concentration of the inoculum, amount, culture time, and culture pH for CLP-6. The number of gene copies of R. solanacearum was significantly inhibited by VOCs produced at pH 5.5 in vivo. The control effect of VOCs emitted at pH 5.5 was 78.91% for tobacco bacterial wilt, which was >3-fold greater than that at pH 7.0. Finally, the main volatile compounds were identified by solid-phase microextraction (SPME)-gas chromatography-mass spectroscopy (GC-MS) as S-methyl thioacetate, methyl thiocyanate, methyl disulfide, 1-decene, 2-ethylhexanol, 1,4-undecadiene, 1-undecene, 1,3-benzothiazole, and 2,5-dimethylpyrazine, and the inhibition rates of 1,3-benzothiazole, 2-ethylhexanolmethyl thiocyanate, dimethyl disulfide, and S-methyl thioacetate were 100%, 100%, 88.91%, 67.64%, and 53.29%, respectively. S-Methyl thioacetate was detected only at pH 5.5. In summary, VOCs produced by P. protegens CLP-6 had strong antagonistic activities against phytopathogens, especially R. solanacearum, under acidic conditions and could be used to develop a safe and additive fumigant against R. solanacearum on tobacco and even other Solanaceae crop bacterial wilt diseases in acidic fields. IMPORTANCE VOCs produced by beneficial bacteria penetrate the rhizosphere to inhibit the growth of plant-pathogenic microorganisms; thus, they have the potential to be used as biological agents in controlling plant diseases. Tobacco bacterial wilt, which is caused by the acidophilic pathogen R. solanacearum, is a major bacterial disease in southern China and is prevalent in acidic soil. In this study, we discovered that the VOCs produced by P. protegens CLP-6 had excellent inhibitory effects on important plant pathogens. Moreover, two of the VOCs, namely, 1,3-benzothiazole and 2-ethylhexanol, had excellent inhibitory effect on R. solanacearum, and another VOC substance, methyl thiocyanate, was produced only at pH 5.5. The VOCs produced by the acid-tolerant strain P. protegens CLP-6 may have potential as environment-friendly microbial fumigant agents for bacterial wilt of tobacco or even other Solanaceae crops in acidic soils in China.
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Volynchikova E, Kim KD. Anti-Oomycete Activity and Pepper Root Colonization of Pseudomonas plecoglossicida YJR13 and Pseudomonas putida YJR92 against Phytophthora capsici. THE PLANT PATHOLOGY JOURNAL 2023; 39:123-135. [PMID: 36760054 PMCID: PMC9929162 DOI: 10.5423/ppj.oa.01.2023.0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 01/17/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Previously, Pseudomonas plecoglossicida YJR13 and Pseudomonas putida YJR92 from a sequential screening procedure were proven to effectively control Phytophthora blight caused by Phytophthora capsici. In this study, we further investigated the anti-oomycete activities of these strains against mycelial growth, zoospore germination, and germ tube elongation of P. capsici. We also investigated root colonization ability of the bacterial strains in square dishes, including cell motility (swimming and swarming motilities) and biofilm formation. Both strains significantly inhibited mycelial growth in liquid and solid V8 juice media and M9 minimal media, zoospore germination, and germ tube elongation compared with Bacillus vallismortis EXTN-1 (positive biocontrol strain), Sphingomonas aquatilis KU408 (negative biocontrol strain), and MgSO4 solution (untreated control). In diluted (nutrient-deficient) V8 juice broth, the tested strain populations were maintained at >108 cells/ml, simultaneously providing mycelial inhibitory activity. Additionally, these strains colonized pepper roots at a 106 cells/ml concentration for 7 days. The root colonization of the strains was supported by strong swimming and swarming activities, biofilm formation, and chemotactic activity towards exudate components (amino acids, organic acids, and sugars) of pepper roots. Collectively, these results suggest that strains YJR13 and YJR92 can effectively suppress Phytophthora blight of pepper through direct anti-oomycete activities against mycelial growth, zoospore germination and germ tube elongation. Bacterial colonization of pepper roots may be mediated by cell motility and biofilm formation together with chemotaxis to root exudates.
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Affiliation(s)
| | - Ki Deok Kim
- Corresponding author: Phone) +82-2-3290-3065, FAX) +82-2-925-1970, E-mail)
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The Inhibitory Effect of Pseudomonas stutzeri YM6 on Aspergillus flavus Growth and Aflatoxins Production by the Production of Volatile Dimethyl Trisulfide. Toxins (Basel) 2022; 14:toxins14110788. [PMID: 36422962 PMCID: PMC9698575 DOI: 10.3390/toxins14110788] [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: 10/13/2022] [Revised: 10/30/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Aspergillus flavus and the produced aflatoxins cause great hazards to food security and human health across all countries. The control of A. flavus and aflatoxins in grains during storage is of great significance to humans. In the current study, bacteria strain YM6 isolated from sea sediment was demonstrated effective in controlling A. flavus by the production of anti-fungal volatiles. According to morphological characteristics and phylogenetic analysis, strain YM6 was identified as Pseudomonas stutzeri. YM6 can produce abundant volatile compounds which could inhibit mycelial growth and conidial germination of A. flavus. Moreover, it greatly prevented fungal infection and aflatoxin production on maize and peanuts during storage. The inhibition rate was 100%. Scanning electron microscopy further supported that the volatiles could destroy the cell structure of A. flavus and prevent conidia germination on the grain surface. Gas chromatography/mass spectrometry revealed that dimethyl trisulfide (DMTS) with a relative abundance of 13% is the most abundant fraction in the volatiles from strain YM6. The minimal inhibitory concentration of DMTS to A. flavus conidia is 200 µL/L (compound volume/airspace volume). Thus, we concluded that Pseudomonas stutzeri YM6 and the produced DMTS showed great inhibition to A. flavus, which could be considered as effective biocontrol agents in further application.
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Kumar P, Gupta A, Mahato DK, Pandhi S, Pandey AK, Kargwal R, Mishra S, Suhag R, Sharma N, Saurabh V, Paul V, Kumar M, Selvakumar R, Gamlath S, Kamle M, Enshasy HAE, Mokhtar JA, Harakeh S. Aflatoxins in Cereals and Cereal-Based Products: Occurrence, Toxicity, Impact on Human Health, and Their Detoxification and Management Strategies. Toxins (Basel) 2022; 14:toxins14100687. [PMID: 36287956 PMCID: PMC9609140 DOI: 10.3390/toxins14100687] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 11/08/2022] Open
Abstract
Cereals and cereal-based products are primary sources of nutrition across the world. However, contamination of these foods with aflatoxins (AFs), secondary metabolites produced by several fungal species, has raised serious concerns. AF generation in innate substrates is influenced by several parameters, including the substrate type, fungus species, moisture content, minerals, humidity, temperature, and physical injury to the kernels. Consumption of AF-contaminated cereals and cereal-based products can lead to both acute and chronic health issues related to physical and mental maturity, reproduction, and the nervous system. Therefore, the precise detection methods, detoxification, and management strategies of AFs in cereal and cereal-based products are crucial for food safety as well as consumer health. Hence, this review provides a brief overview of the occurrence, chemical characteristics, biosynthetic processes, health hazards, and detection techniques of AFs, along with a focus on detoxification and management strategies that could be implemented for food safety and security.
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Affiliation(s)
- Pradeep Kumar
- Department of Botany, University of Lucknow, Lucknow 226007, India
- Applied Microbiology Laboratory, Department of Forestry, North Eastern Regional Institute of Science and Technology, Nirjuli 791109, India
- Correspondence: (P.K.); (D.K.M.)
| | - Akansha Gupta
- Department of Dairy Science and Food Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India
- CASS Food Research Centre, School of Exercise and Nutrition Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - Dipendra Kumar Mahato
- CASS Food Research Centre, School of Exercise and Nutrition Sciences, Deakin University, Burwood, VIC 3125, Australia
- Correspondence: (P.K.); (D.K.M.)
| | - Shikha Pandhi
- Department of Dairy Science and Food Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Arun Kumar Pandey
- MMICT&BM(HM), Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala 133207, India
| | - Raveena Kargwal
- Department of Processing and Food Engineering, College of Agricultural Engineering and Technology, Chaudhary Charan Singh Haryana Agricultural University, Hisar 125004, India
| | - Sadhna Mishra
- Department of Dairy Science and Food Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India
- Faculty of Agricultural Sciences, GLA University, Mathura 281406, India
| | - Rajat Suhag
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100 Bolzano, Italy
| | - Nitya Sharma
- Food and Bioprocess Engineering Laboratory, Centre for Rural Development and Technology, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Vivek Saurabh
- Division of Food Science and Postharvest Technology, ICAR—Indian Agricultural Research Institute, New Delhi 110012, India
| | - Veena Paul
- Department of Dairy Science and Food Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India
| | - Manoj Kumar
- Chemical and Biochemical Processing Division, ICAR—Central Institute for Research on Cotton Technology, Mumbai 400019, India
| | - Raman Selvakumar
- Centre for Protected Cultivation Technology, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi 110012, India
| | - Shirani Gamlath
- CASS Food Research Centre, School of Exercise and Nutrition Sciences, Deakin University, Burwood, VIC 3125, Australia
| | - Madhu Kamle
- Applied Microbiology Laboratory, Department of Forestry, North Eastern Regional Institute of Science and Technology, Nirjuli 791109, India
| | - Hesham Ali El Enshasy
- Institute of Bioproduct Development, Universiti Teknologi Malaysia (UTM), Skudai 81310, Malaysia
- City of Scientific Research and Technology Applications, New Burg Al Arab, Alexandria 21934, Egypt
| | - Jawahir A. Mokhtar
- Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University Hospital, Jeddah 21589, Saudi Arabia
- Vaccines and Immunotherapy Unit, King Fahad Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Steve Harakeh
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Yousef Abdul Latif Jameel Scientific Chair of Prophetic Medicine Application, Faculty of Medicine (FM), King Abdulaziz University, Jeddah 21589, Saudi Arabia
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Draft Genome Sequence of Priestia sp. Strain TSO9, a Plant Growth-Promoting Bacterium Associated with Wheat (Triticum turgidum subsp. durum) in the Yaqui Valley, Mexico. PLANTS 2022; 11:plants11172231. [PMID: 36079613 PMCID: PMC9460074 DOI: 10.3390/plants11172231] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/11/2022] [Accepted: 08/26/2022] [Indexed: 11/16/2022]
Abstract
Strain TSO9 was isolated from a commercial field of wheat (Triticum turgidum L. subsp. durum) located in the Yaqui, Valley, Mexico. Here, the genome of this strain was sequenced, obtaining a total of 5,248,515 bp; 38.0% G + C content; 1,186,514 bp N50; and 2 L50. Based on the 16S rRNA gene sequencing, strain TSO9 was affiliated with the genus Priestia. The genome annotation of Priestia sp. TSO9 contains a total of 147 RNAs, 128 tRNAs, 1 tmRNA, and 5512 coding DNA sequences (CDS) distributed into 332 subsystems, where CDS associated with agricultural purposes were identified, such as (i) virulence, disease, and defense (57 CDS) (i.e., resistance to antibiotics and toxic compounds (34 CDS), invasion and intracellular resistance (12 CDS), and bacteriocins and ribosomally synthesized antibacterial peptides (10 CDS)), (ii) iron acquisition and metabolism (36 CDS), and (iii) secondary metabolism (4 CDS), i.e., auxin biosynthesis. In addition, subsystems related to the viability of an active ingredient for agricultural bioproducts were identified, such as (i) stress response (65 CDS). These genomic traits are correlated with the metabolic background of this strain, and its positive effects on wheat growth regulation reported in this work. Thus, further investigations of Priestia sp. TSO9 are necessary to complement findings regarding its application in agroecosystems to increase wheat yield sustainably.
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Chowdhury NN, Islam MN, Jafrin R, Rauf A, Khalil AA, Emran TB, Aljohani ASM, Alhumaydhi FA, Lorenzo JM, Shariati MA, Simal-Gandara J. Natural plant products as effective alternatives to synthetic chemicals for postharvest fruit storage management. Crit Rev Food Sci Nutr 2022; 63:10332-10350. [PMID: 35612470 DOI: 10.1080/10408398.2022.2079112] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Fruits contain enormous source of vitamins that provides energy to the human body. These are also affluent in essential and vital vitamins, minerals, fiber, and health-promoting components, which has led to an increase in fruit consumption in recent years. Though fruit consumption has expanded considerably in recent years, the use of synthetic chemicals to ripen or store fruits has been steadily increasing, resulting in postharvest deterioration. Alternatives to synthetic chemicals should be considered to control this problem. Instead of utilizing synthetic chemicals, this study suggests using natural plant products to control postharvest decay. The aim of this study indicates how natural plant products can be useful and effective to eliminate postharvest diseases rather than using synthetic chemicals. Several electronic databases were investigated as information sources, including Google Scholar, PubMed, Web of Science, Scopus, ScienceDirect, SpringerLink, Semantic Scholar, MEDLINE, and CNKI Scholar. The current review focused on the postharvest of fruits has become more and more necessary because of these vast demands of fruits. Pathogen-induced diseases are the main component and so the vast portion of fruits get wasted after harvest. Besides, it may occur harmful during harvesting and subsequent handling, storage, and marketing and after consumer purchasing and also causes for numerous endogenous and exogenous diseases via activating ROS, oxidative stress, lipid peroxidation, etc. However, pathogenicity can be halted by using postharvest originating natural fruits containing bioactive elements that may be responsible for the management of nutritional deficiency, inflammation, cancer, and so on. However, issues arising during the postharvest diseases must be controlled and resolved before releasing the horticultural commodities for commercialization. Therefore, the control of postharvest pathogens still depends on the use of synthetic fungicides; however, due to the problem of the development of the fungicide-resistant strains there is a good demand of public to eradicate the use of pesticides with the arrival of numerous diseases that are expanded in their intensity by the specific chemical product. By using of the organic or natural products for controlling postharvest diseases of fruits has become a mandatory step to take. In addition, antimicrobial packaging may have a greater impact on long-term food security by lowering the risk of pathogenicity and increasing the longevity of fruit shelf life. Taken together, natural chemicals as acetaldehyde, hexanal, eugenol, linalool, jasmonates, glucosinolates, essential oils, and many plant bioactive are reported for combating of the postharvest illnesses and guide to way of storage of fruits in this review.
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Affiliation(s)
- Nahidun Nesa Chowdhury
- Department of Pharmacy, International Islamic University Chittagong, Chittagong, Bangladesh
| | - Mohammad Nazmul Islam
- Department of Pharmacy, International Islamic University Chittagong, Chittagong, Bangladesh
| | - Rifat Jafrin
- Department of Pharmacy, International Islamic University Chittagong, Chittagong, Bangladesh
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Anbar, Khyber Pakhtunkhwa, Pakistan
| | - Anees Ahmed Khalil
- University Institute of Diet and Nutritional Sciences, Faculty of Allied Health Sciences, The University of Lahore, Pakistan
| | - Talha Bin Emran
- Department of Pharmacy, BGC Trust University Bangladesh, Chittagong, Bangladesh
| | - Abdullah S M Aljohani
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University, Buraydah, Saudi Arabia
| | - Fahad A Alhumaydhi
- Department of Medical Laboratories, College of Applied Medical Sciences, Qassim University, Buraydah, Saudi Arabia
| | - Jose M Lorenzo
- Centro Tecnológico de la Carne de Galicia, Ourense, Spain
- Área de Tecnología de los Alimentos, Facultad de Ciencias de Ourense, Universidad de Vigo, Ourense, Spain
| | - Mohammad Ali Shariati
- K.G. Razumovsky Moscow State University of Technologies and Management, The First Cossack University), Moscow, Russia
| | - Jesus Simal-Gandara
- Universidade de Vigo, Nutrition and Bromatology Group, Analytical Chemistry and Food Science Department, Faculty of Science, Ourense, Spain
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Mutungi PM, Wekesa VW, Onguso J, Kanga E, Baleba SBS, Boga HI. Culturable Bacterial Endophytes Associated With Shrubs Growing Along the Draw-Down Zone of Lake Bogoria, Kenya: Assessment of Antifungal Potential Against Fusarium solani and Induction of Bean Root Rot Protection. FRONTIERS IN PLANT SCIENCE 2022; 12:796847. [PMID: 35222451 PMCID: PMC8864308 DOI: 10.3389/fpls.2021.796847] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Vascular shrubs growing along the draw-down zones of saline lakes must develop adaptive mechanisms to cope with high salinity, erratic environmental conditions, and other biotic and abiotic stresses. Microbial endophytes from plants growing in these unique environments harbor diverse metabolic and genetic profiles that play an important role in plant growth, health, and survival under stressful conditions. A variety of bacterial endophytes have been isolated from salt tolerant plants but their potential applications in agriculture have not been fully explored. To further address this gap, the present study sought to isolate culturable bacterial endophytes from shrubs growing along the draw-down zone of Lake Bogoria, a saline alkaline lake, and examined their functional characteristics and potential in the biocontrol of the bean root rot pathogen, Fusarium solani. We collected shrubs growing within 5 m distance from the shoreline of Lake Bogoria and isolated 69 bacterial endophytes. The endophytic bacteria were affiliated to three different phyla (Firmicutes, Proteobacteria, and Actinobacteria) with a bias in the genera, Bacillus, and they showed no tissue or plant specificity. All selected isolates were positive for catalase enzyme grown in 1.5 M NaCl; three isolates (B23, B19, and B53) produced indole acetic acid (IAA) and only one isolate, B23 did not solubilize phosphate on Pikovskaya agar. Isolates, B19 and B53 exhibited more than 50% of mycelial inhibition in the dual culture assay and completely inhibited the germination of F. solani spores in co-culture assays while two isolates, B07 and B39 had delayed fungal spore germination after an overnight incubation. All isolates were able to establish endophytic association in the roots, stems, and leaves of been seedlings in both seed soaking and drenching methods. Colonization of bean seedlings by the bacterial endophytes, B19 and B53 resulted in the biocontrol of F. solani in planta, reduced disease severity and incidence, and significantly increased both root and shoot biomass compared to the control. Taxonomic identification using 16S rRNA revealed that the two isolates belong to Enterobacter hormaechei subsp., Xiangfangensis and Bacillus megaterium. Our results demonstrate the potential use of these two isolates in the biocontrol of the bean root rot pathogen, F. solani and plant growth promotion.
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Affiliation(s)
- Priscillar Mumo Mutungi
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
- Ecological Monitoring Department, Kenya Wildlife Service, Nairobi, Kenya
| | | | - Justus Onguso
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Erustus Kanga
- State Department for Wildlife, Ministry of Tourism and Wildlife, Nairobi, Kenya
| | - Steve B. S. Baleba
- Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Hamadi Iddi Boga
- Botany Department, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
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Liu K, Zhang C, Xu J, Liu Q. Research advance in gas detection of volatile organic compounds released in rice quality deterioration process. Compr Rev Food Sci Food Saf 2021; 20:5802-5828. [PMID: 34668316 DOI: 10.1111/1541-4337.12846] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 08/04/2021] [Accepted: 08/24/2021] [Indexed: 11/30/2022]
Abstract
Rice quality deterioration will cause grievous waste of stored grain and various food safety problems. Gas detection of volatile organic compounds (VOCs) produced by deterioration is a nondestructive detection method to judge rice quality and alleviate rice spoilage. This review discussed the research advance of VOCs detection in terms of nondestructive detection methods of rice quality deterioration, applications of VOCs in grain detection, inspection of characteristic gas produced during rice spoilage, rice deterioration prevention and control, and detection of VOCs released by rice mildew and insect attack. According to the main causes of rice quality deterioration and major sources of VOCs with off-odor generated during rice storage, deterioration can be divided into mold and insect infection. The results of literature manifested that researches mainly focused on the infection of Aspergillus in the mildew process and the attack of certain pests in recent years, thus the research scope was limited. In this paper, the gas detection methods combined with the chemometrics to qualitatively analyze the VOCs, as well as the correlation with the number of colonies and insects were further studied based on the common dominant strains during rice mildew, that is, Aspergillus and Penicillium fungi, and the common pests during storage, that is, Sitophilus oryzae and Rhyzopertha dominica. Furthermore, this paper pointed out that the quantitative determination of characteristic VOCs, the numeration relationship between VOCs and the degree of mildew and insect infestation, the further expansion of detection range, and the application of degraded rice should be the spotlight of future research.
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Affiliation(s)
- Kewei Liu
- College of Mechanical Engineering, Yangzhou University, Yangzhou, People's Republic of China
| | - Chao Zhang
- College of Mechanical Engineering, Yangzhou University, Yangzhou, People's Republic of China
| | - Jinyong Xu
- College of Mechanical Engineering, Yangzhou University, Yangzhou, People's Republic of China
| | - Qiaoquan Liu
- Key Laboratories of Crop Genetics and Physiology of Jiangsu Province, Co-Innovation Center for Modern Production Technology of Grain Crops of Jiangsu, Yangzhou University, Yangzhou, People's Republic of China
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12
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The "beauty in the beast"-the multiple uses of Priestia megaterium in biotechnology. Appl Microbiol Biotechnol 2021; 105:5719-5737. [PMID: 34263356 PMCID: PMC8390425 DOI: 10.1007/s00253-021-11424-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 01/05/2023]
Abstract
Abstract Over 30 years, the Gram-positive bacterium Priestia megaterium (previously known as Bacillus megaterium) was systematically developed for biotechnological applications ranging from the production of small molecules like vitamin B12, over polymers like polyhydroxybutyrate (PHB) up to the in vivo and in vitro synthesis of multiple proteins and finally whole-cell applications. Here we describe the use of the natural vitamin B12 (cobalamin) producer P. megaterium for the elucidation of the biosynthetic pathway and the subsequent systematic knowledge-based development for production purposes. The formation of PHB, a natural product of P. megaterium and potential petro-plastic substitute, is covered and discussed. Further important biotechnological characteristics of P. megaterium for recombinant protein production including high protein secretion capacity and simple cultivation on value-added carbon sources are outlined. This includes the advanced system with almost 30 commercially available expression vectors for the intracellular and extracellular production of recombinant proteins at the g/L scale. We also revealed a novel P. megaterium transcription-translation system as a complementary and versatile biotechnological tool kit. As an impressive biotechnology application, the formation of various cytochrome P450 is also critically highlighted. Finally, whole cellular applications in plant protection are completing the overall picture of P. megaterium as a versatile giant cell factory. Key points • The use of Priestia megaterium for the biosynthesis of small molecules and recombinant proteins through to whole-cell applications is reviewed. • P. megaterium can act as a promising alternative host in biotechnological production processes.
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13
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Saleh AE, Ul-Hassan Z, Zeidan R, Al-Shamary N, Al-Yafei T, Alnaimi H, Higazy NS, Migheli Q, Jaoua S. Biocontrol Activity of Bacillus megaterium BM344-1 against Toxigenic Fungi. ACS OMEGA 2021; 6:10984-10990. [PMID: 34056251 PMCID: PMC8153935 DOI: 10.1021/acsomega.1c00816] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
Mycotoxins are secondary metabolites of some fungal species and represent important contaminants of food and feed. This study aimed to explore the biological control activity of Bacillus megaterium BM344-1 volatile organic compounds (VOCs) on the growth and mycotoxin production of single representatives of the toxigenic species Aspergillus flavus, Aspergillus carbonarius, Penicillium verrucosum, and Fusarium verticillioides. In vitro co-incubation experiments indicated the P. verrucosum isolate as the most sensitive one, with a growth inhibition ratio of 66.7%, followed by A. flavus (29.4%) and F. verticillioides (18.2%). Exposure of A. flavus, P. verrucosum, and F. verticillioides to BM344-1 VOCs resulted in complete inhibition of aflatoxins (AFB1, AFG1, and AFG2), ochratoxin A, and fumonisin B1 (FB1) synthesis on artificial media, respectively. In vivo experiments on maize kernels showed 51% inhibition of fungal growth on ears simultaneously infected with A. flavus spores and exposed to BM344-1 volatiles. Likewise, AF synthesis by A. flavus was significantly (p < 0.05) inhibited (25.34 ± 6.72 μg/kg) by bacterial volatiles as compared to that in control maize ears (91.81 ± 29.10 μg/kg). Gas chromatography-tandem mass spectrometry-based analysis of headspace volatiles revealed hexadecanoic acid methyl ester (palmitic acid) and tetracosane as bioactive compounds in the BM344-1 volatilome. Bacterial volatiles have promising potential to control the growth and mycotoxin synthesis of toxigenic fungi and may present valuable aid in the efforts to warrant food and feed safety.
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Affiliation(s)
- Aya Ehab Saleh
- Department
of Biological and Environmental Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Zahoor Ul-Hassan
- Department
of Biological and Environmental Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Randa Zeidan
- Department
of Biological and Environmental Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Noora Al-Shamary
- Environmental
Science Center, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Thoraya Al-Yafei
- Environmental
Science Center, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Hajer Alnaimi
- Environmental
Science Center, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Nayla Salah Higazy
- Department
of Biological and Environmental Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha 2713, Qatar
| | - Quirico Migheli
- Dipartimento
di Agraria and Desertification Research Centre (NRD), Università degli Studi di Sassari, Viale Italia 39, Sassari I-07100, Italy
| | - Samir Jaoua
- Department
of Biological and Environmental Sciences, College of Arts and Science, Qatar University, P.O. Box 2713, Doha 2713, Qatar
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14
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Rodrigues AI, Gudiña EJ, Abrunhosa L, Malheiro AR, Fernandes R, Teixeira JA, Rodrigues LR. Rhamnolipids inhibit aflatoxins production in Aspergillus flavus by causing structural damages in the fungal hyphae and down-regulating the expression of their biosynthetic genes. Int J Food Microbiol 2021; 348:109207. [PMID: 33930837 DOI: 10.1016/j.ijfoodmicro.2021.109207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 04/05/2021] [Accepted: 04/16/2021] [Indexed: 11/28/2022]
Abstract
Aflatoxins are hepatotoxic and carcinogenic fungal secondary metabolites that usually contaminate crops and represent a serious health hazard for humans and animals worldwide. In this work, the effect of rhamnolipids (RLs) produced by Pseudomonas aeruginosa #112 on the growth and aflatoxins production by Aspergillus flavus MUM 17.14 was studied in vitro. At concentrations between 45 and 1500 mg/L, RLs reduced the mycelial growth of A. flavus by 23-40% and the production of aflatoxins by 93.9-99.5%. Purified mono-RLs and di-RLs exhibited a similar inhibitory activity on fungal growth. However, the RL mixture had a stronger inhibitory effect on aflatoxins production at concentrations up to 190 mg/L, probably due to a synergistic effect resulting from the combination of both congeners. Using transmission electron microscopy, it was demonstrated that RLs damaged the cell wall and the cytoplasmic membrane of the fungus, leading to the loss of intracellular content. This disruptive phenomenon explains the growth inhibition observed. Furthermore, RLs down-regulated the expression of genes aflC, aflE, aflP and aflQ involved in the aflatoxins biosynthetic pathway (6.4, 44.3, 38.1 and 2.0-fold, respectively), which is in agreement with the almost complete inhibition of aflatoxins production. Overall, the results herein gathered demonstrate for the first time that RLs could be used against aflatoxigenic fungi to attenuate the production of aflatoxins, and unraveled some of their mechanisms of action.
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Affiliation(s)
- Ana I Rodrigues
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal
| | - Eduardo J Gudiña
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
| | - Luís Abrunhosa
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal
| | - Ana R Malheiro
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, 4200-135 Porto, Portugal
| | - Rui Fernandes
- Instituto de Investigação e Inovação em Saúde (I3S), Universidade do Porto, 4200-135 Porto, Portugal
| | - José A Teixeira
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal
| | - Lígia R Rodrigues
- CEB - Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal
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15
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Noskov YA, Kabilov MR, Polenogova OV, Yurchenko YA, Belevich OE, Yaroslavtseva ON, Alikina TY, Byvaltsev AM, Rotskaya UN, Morozova VV, Glupov VV, Kryukov VY. A Neurotoxic Insecticide Promotes Fungal Infection in Aedes aegypti Larvae by Altering the Bacterial Community. MICROBIAL ECOLOGY 2021; 81:493-505. [PMID: 32839879 DOI: 10.1007/s00248-020-01567-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Symbiotic bacteria have a significant impact on the formation of defensive mechanisms against fungal pathogens and insecticides. The microbiome of the mosquito Aedes aegypti has been well studied; however, there are no data on the influence of insecticides and pathogenic fungi on its structure. The fungus Metarhizium robertsii and a neurotoxic insecticide (avermectin complex) interact synergistically, and the colonization of larvae with hyphal bodies is observed after fungal and combined (conidia + avermectins) treatments. The changes in the bacterial communities (16S rRNA) of Ae. aegypti larvae under the influence of fungal infection, avermectin toxicosis, and their combination were studied. In addition, we studied the interactions between the fungus and the predominant cultivable bacteria in vitro and in vivo after the coinfection of the larvae. Avermectins increased the total bacterial load and diversity. The fungus decreased the diversity and insignificantly increased the bacterial load. Importantly, avermectins reduced the relative abundance of Microbacterium (Actinobacteria), which exhibited a strong antagonistic effect towards the fungus in in vitro and in vivo assays. The avermectin treatment led to an increased abundance of Chryseobacterium (Flavobacteria), which exerted a neutral effect on mycosis development. In addition, avermectin treatment led to an elevation of some subdominant bacteria (Pseudomonas) that interacted synergistically with the fungus. We suggest that avermectins change the bacterial community to favor the development of fungal infection.
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Affiliation(s)
- Y A Noskov
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091.
- National Research Tomsk State University, Tomsk, Russia, 634050.
| | - M R Kabilov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630090
| | - O V Polenogova
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - Y A Yurchenko
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - O E Belevich
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - O N Yaroslavtseva
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - T Y Alikina
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630090
| | - A M Byvaltsev
- Novosibirsk State University, Novosibirsk, Russia, 630090
| | - U N Rotskaya
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - V V Morozova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630090
| | - V V Glupov
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
| | - V Y Kryukov
- Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, 630091
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16
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Wang Z, Zhu Y, Jing R, Wu X, Li N, Liu H, Zhang X, Wang W, Liu Y. High-throughput sequencing-based analysis of the composition and diversity of endophytic bacterial community in seeds of upland rice. Arch Microbiol 2020; 203:609-620. [PMID: 32995980 DOI: 10.1007/s00203-020-02058-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/17/2020] [Accepted: 09/19/2020] [Indexed: 01/07/2023]
Abstract
Upland rice is an ecotype crop resulting from the long-term domestication and evolution of rice in dry land without a water layer. Generally, the stems and leaves are thick and luxuriant, while the leaves also typically broad and light. The root system is developed with abundant root hair, and the osmotic pressure of the root and cell juice concentration in the leaves is high, while this plant is drought-resistant, heat-resistant, and water absorbent. This study aims to reveal the "core flora" of the endophytes in upland rice seeds by examining their diversity and community structures. It further intends to reveal the impact of the soil environment on the formation of endophyte community structures in upland rice seeds by comparing the environmental soil microorganisms in upland rice habitats. In this study, high-throughput sequencing technology based on the Illumina Hiseq 2500 platform was used to investigate the structure and diversity of endophytic bacterial communities using upland rice varieties collected from different locations and soil samples from unified planting sites as materials. Here, 42 endophytic OTUs were found to coexist in the 14 samples. At the phylum level, the first dominant phyla in all the samples were Proteobacteria (93.81-99.99%). At the genus level, Pantoea (8.77-87.77%), Pseudomonas (1.15-61.58%), Methylobacterium (0.40-4.64%), Sphingomonas (0.26-3.85%), Microbacterium (0.01-4.67%) and Aurantimonas (0.04-4.34%), which represent the core microflora in upland rice seeds, served as the dominant genera that coexisted in all the upland rice seeds tested. This study significant for the isolation, screening, functional evaluation, and re-action of various functional microorganisms in upland rice to improve its agronomic traits. It also provides a specific reference for the interaction between microorganisms and plants.
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Affiliation(s)
- Zhishan Wang
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yongqiang Zhu
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center At Shanghai, Shanghai, 201203, China
| | - Ruixue Jing
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xianyu Wu
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Ni Li
- State Key Laboratory of Hybrid Rice (Hunan Hybrid Rice Research Center), Changsha, 410125, China
| | - Hai Liu
- State Key Laboratory of Hybrid Rice (Hunan Hybrid Rice Research Center), Changsha, 410125, China
| | - Xiaoxia Zhang
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Weiping Wang
- State Key Laboratory of Hybrid Rice (Hunan Hybrid Rice Research Center), Changsha, 410125, China.
| | - Yang Liu
- School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
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17
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Ren X, Zhang Q, Zhang W, Mao J, Li P. Control of Aflatoxigenic Molds by Antagonistic Microorganisms: Inhibitory Behaviors, Bioactive Compounds, Related Mechanisms, and Influencing Factors. Toxins (Basel) 2020; 12:E24. [PMID: 31906282 PMCID: PMC7020460 DOI: 10.3390/toxins12010024] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/29/2019] [Accepted: 12/11/2019] [Indexed: 12/21/2022] Open
Abstract
Aflatoxin contamination has been causing great concern worldwide due to the major economic impact on crop production and their toxicological effects to human and animals. Contamination can occur in the field, during transportation, and also in storage. Post-harvest contamination usually derives from the pre-harvest infection of aflatoxigenic molds, especially aflatoxin-producing Aspergilli such as Aspergillusflavus and A. parasiticus. Many strategies preventing aflatoxigenic molds from entering food and feed chains have been reported, among which biological control is becoming one of the most praised strategies. The objective of this article is to review the biocontrol strategy for inhibiting the growth of and aflatoxin production by aflatoxigenic fungi. This review focuses on comparing inhibitory behaviors of different antagonistic microorganisms including various bacteria, fungi and yeasts. We also reviewed the bioactive compounds produced by microorganisms and the mechanisms leading to inhibition. The key factors influencing antifungal activities of antagonists are also discussed in this review.
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Affiliation(s)
- Xianfeng Ren
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (X.R.); (W.Z.); (J.M.)
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
| | - Qi Zhang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (X.R.); (W.Z.); (J.M.)
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
| | - Wen Zhang
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (X.R.); (W.Z.); (J.M.)
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
| | - Jin Mao
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (X.R.); (W.Z.); (J.M.)
- Laboratory of Risk Assessment for Oilseeds Products, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
| | - Peiwu Li
- Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China; (X.R.); (W.Z.); (J.M.)
- Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
- Key Laboratory of Detection for Mycotoxins, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
- Laboratory of Risk Assessment for Oilseeds Products, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
- Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture and Rural Affairs, Wuhan 430062, China
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18
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In-vitro Application of a Qatari Burkholderia cepacia strain (QBC03) in the Biocontrol of Mycotoxigenic Fungi and in the Reduction of Ochratoxin A biosynthesis by Aspergillus carbonarius. Toxins (Basel) 2019; 11:toxins11120700. [PMID: 31810315 PMCID: PMC6950548 DOI: 10.3390/toxins11120700] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 11/17/2019] [Accepted: 11/26/2019] [Indexed: 01/12/2023] Open
Abstract
Mycotoxins are secondary metabolites produced by certain filamentous fungi, causing human and animal health issues upon the ingestion of contaminated food and feed. Among the safest approaches to the control of mycotoxigenic fungi and mycotoxin detoxification is the application of microbial biocontrol agents. Burkholderiacepacia is known for producing metabolites active against a broad number of pathogenic fungi. In this study, the antifungal potential of a Qatari strain of Burkholderia cepacia (QBC03) was explored. QBC03 exhibited antifungal activity against a wide range of mycotoxigenic, as well as phytopathogenic, fungal genera and species. The QBC03 culture supernatant significantly inhibited the growth of Aspergillus carbonarius, Fusarium culmorum and Penicillium verrucosum in PDA medium, as well as A. carbonarius and P. verrucosum biomass in PDB medium. The QBC03 culture supernatant was found to dramatically reduce the synthesis of ochratoxin A (OTA) by A. carbonarius, in addition to inducing mycelia malformation. The antifungal activity of QBC03’s culture extract was retained following thermal treatment at 100 °C for 30 min. The findings of the present study advocate that QBC03 is a suitable biocontrol agent against toxigenic fungi, due to the inhibitory activity of its thermostable metabolites.
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19
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Lagogianni CS, Tsitsigiannis DI. Effective Biopesticides and Biostimulants to Reduce Aflatoxins in Maize Fields. Front Microbiol 2019; 10:2645. [PMID: 31824451 PMCID: PMC6881375 DOI: 10.3389/fmicb.2019.02645] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 10/30/2019] [Indexed: 11/16/2022] Open
Abstract
The presence of ear rots in maize caused by Aspergillus flavus that are also associated with the production of aflatoxins has evolved into an increasing problem over the last few years. Since no commercial biological control products are still available to control A. flavus in maize in Europe, this study targets to the evaluation of six biopesticides/biostimulants (Botector®, Mycostop®, Serenade Max®, Trianum®, Vacciplant®, and zeolite) for the control of A. flavus and the derived aflatoxins in in vitro and maize field bioassays. Mycostop®, Serenade Max®, Vacciplant®, and zeolite reduced significantly A. flavus conidia production by 38.8–63.1%, and most of them were able to reduce aflatoxin B1 (AFB1) production in laboratory studies. Mycostop®, Trianum®, and Botector® were effective in reducing AFB1, in vitro. In the field, Mycostop® and Botector® treatments resulted in significant reduction of the disease severity (16.5 and 21.9%, respectively) and decreased significantly AFB1 content in maize kernels by 43.05 and 43.09%, respectively. For the first time, these results demonstrated the potential of commercial non-chemical products to suppress disease symptoms and aflatoxin content caused by A. flavus in maize under laboratory and field conditions.
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Affiliation(s)
- Christina S Lagogianni
- Laboratory of Plant Pathology, Department of Crop Science, School of Plant Sciences, Agricultural University of Athens, Athens, Greece
| | - Dimitrios I Tsitsigiannis
- Laboratory of Plant Pathology, Department of Crop Science, School of Plant Sciences, Agricultural University of Athens, Athens, Greece
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20
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Ul Hassan Z, Al Thani R, Alnaimi H, Migheli Q, Jaoua S. Investigation and Application of Bacillus licheniformis Volatile Compounds for the Biological Control of Toxigenic Aspergillus and Penicillium spp. ACS OMEGA 2019; 4:17186-17193. [PMID: 31656892 PMCID: PMC6811857 DOI: 10.1021/acsomega.9b01638] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 09/25/2019] [Indexed: 05/08/2023]
Abstract
The present study was designed to investigate the antagonistic activity of Bacillus licheniformis BL350-2 against mycotoxigenic strains of Aspergillus and Penicillium. In vitro coincubation for 5 days indicated Aspergillus westerdijkiae BA1 as the most sensitive strain, with a growth inhibition of 62%, followed by A. carbonarius MG7 (60%), Penicillium verrucosum MC12 (53%), A. niger MC05 (50%), A. flavus CM5 (49%), A. parasiticus SB01 (47%), and A. ochraceus MD1 (44%). Likewise, the majority of the tested strains on exposure to bacterial volatiles showed complete inhibition of mycotoxin synthesis. In vivo assays on maize ears resulted in 88% reduction in A. flavus CM5 growth and complete inhibition of fungal sporulation and aflatoxin accumulation. The GC-MS-based volatile profile showed 3-methyl-1-butanol as the most abundant compound. The findings of the present study advocate that B. licheniformis BL350-2 is suitable as a biocontrol agent against mycotoxigenic fungi, at least during storage of cereal grains.
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Affiliation(s)
- Zahoor Ul Hassan
- Department
of Biological and Environmental Sciences, College of Arts
and Science and Environmental Science Center, Qatar University, P. O. Box 2713, Doha, Qatar
| | - Roda Al Thani
- Department
of Biological and Environmental Sciences, College of Arts
and Science and Environmental Science Center, Qatar University, P. O. Box 2713, Doha, Qatar
| | - Hajer Alnaimi
- Department
of Biological and Environmental Sciences, College of Arts
and Science and Environmental Science Center, Qatar University, P. O. Box 2713, Doha, Qatar
| | - Quirico Migheli
- Dipartimento
di Agraria, Università degli Studi
di Sassari, Viale Italia 39, I-07100 Sassari, Italy
| | - Samir Jaoua
- Department
of Biological and Environmental Sciences, College of Arts
and Science and Environmental Science Center, Qatar University, P. O. Box 2713, Doha, Qatar
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21
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Pennerman KK, Scarsella JB, Yin GH, Hua SST, Hartman TG, Bennett JW. Volatile 1-octen-3-ol increases patulin production by Penicillium expansum on a patulin-suppressing medium. Mycotoxin Res 2019; 35:329-340. [PMID: 31025195 DOI: 10.1007/s12550-019-00348-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 02/26/2019] [Accepted: 02/27/2019] [Indexed: 12/21/2022]
Abstract
1-Octen-3-ol is one of the most abundant volatile compounds associated with fungi and functions as a germination and growth inhibitor in several species. By investigating its effect on the biosynthesis of patulin, a mycotoxin made by Penicillium expansum, it was found that a sub-inhibitory level of volatile 1-octen-3-ol increased accumulation of patulin on a medium that normally suppresses the mycotoxin. Transcriptomic sequencing and comparisons of control and treated P. expansum grown on potato dextrose agar (PDA; patulin permissive) or secondary medium agar (SMA; patulin suppressive) revealed that the expression of gox2, a gene encoding a glucose oxidase, was significantly affected, decreasing 10-fold on PDA and increasing 85-fold on SMA. Thirty other genes, mostly involved in transmembrane transport, oxidation-reduction, and carbohydrate metabolism were also differently expressed on the two media. Transcription factors previously found to be involved in regulation of patulin biosynthesis were not significantly affected despite 1-octen-3-ol increasing patulin production on SMA. Further study is needed to determine the relationship between the upregulation of patulin biosynthesis genes and gox2 on SMA, and to identify the molecular mechanism by which 1-octen-3-ol induced this effect.
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Affiliation(s)
- Kayla K Pennerman
- Department of Plant Biology, Rutgers University, The State University of New Jersey, New Brunswick, NJ, 08901, USA.
| | - Joseph B Scarsella
- Department of Food Science, Rutgers University, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Guo-Hua Yin
- Department of Plant Biology, Rutgers University, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Sui-Sheng T Hua
- Foodborne Toxin Detection and Prevention Research, United States Department of Agriculture, Agricultural Research Service, Albany, CA, 94710, USA
| | - Thomas G Hartman
- Department of Food Science, Rutgers University, The State University of New Jersey, New Brunswick, NJ, 08901, USA
| | - Joan W Bennett
- Department of Plant Biology, Rutgers University, The State University of New Jersey, New Brunswick, NJ, 08901, USA
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22
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Tchagang CF, Xu R, Overy D, Blackwell B, Chabot D, Hubbard K, Doumbou CL, Bromfield ESP, Tambong JT. Diversity of bacteria associated with corn roots inoculated with Canadian woodland soils, and description of Pseudomonas aylmerense sp. nov. Heliyon 2018; 4:e00761. [PMID: 30186983 PMCID: PMC6120581 DOI: 10.1016/j.heliyon.2018.e00761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 08/24/2018] [Accepted: 08/24/2018] [Indexed: 11/15/2022] Open
Abstract
Bacteria associated with corn roots inoculated with soils collected from the Canadian woodlands were isolated and characterized. Genus-level identification based on 16S rRNA sequence analysis classified the 161 isolates in 19 genera. The majority (64%) of the isolates were affiliated with the genus Pseudomonas. Further analysis of the Pseudomonas isolates based on BLASTn and rpoD-rpoB-gyrB concatenated gene phylogeny revealed three unique clusters that could not be assigned to known species. This study reports the taxonomic description of one of the distinct lineages represented by two strains (S1E40T and S1E44) with P. lurida LMG 21995T, P. costantinii LMG 22119T, P. palleroniana LMG 23076T, P. simiae CCUG 50988T and P. extremorientalis LMG 19695T as the closest taxa. Both strains showed low ANIm (<90%) and genome-based DNA-DNA hybridization (<50%) values, which unequivocally delineated the new strains from the closest relatives. These findings were supported by multilocus sequence analysis (MLSA) and DNA fingerprinting. In addition, growth characteristics and biochemical tests revealed patterns that differed from the related species. Strains S1E40T and S1E44 are Gram-negative, aerobic, rod-shaped and motile by at least one flagellum; and grew optimally at 30 °C. The predominant polar lipid is phosphatidylethanolamine while the major respiratory quinone is ubiquinone-9. Based on phenotypic and genotypic data presented here, strains S1E40T and S1E44 represent a novel species for which the name Pseudomonas aylmerense sp. nov. is proposed. The type strain is S1E40T (= LMG 30784T = DOAB 703T = HAMI 3696T) with a G + C content of 61.6%.
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Affiliation(s)
- Caetanie F Tchagang
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada.,Institut des sciences de la santé et de la vie, Collège La Cité, 801 Aviation Parkway, Ottawa, Ontario, Canada
| | - Renlin Xu
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - David Overy
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Barbara Blackwell
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Denise Chabot
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Keith Hubbard
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - Cyr Lézin Doumbou
- Institut des sciences de la santé et de la vie, Collège La Cité, 801 Aviation Parkway, Ottawa, Ontario, Canada
| | - Eden S P Bromfield
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
| | - James T Tambong
- Ottawa Research and Development Centre, 960 Carling Avenue, Ottawa, Ontario K1A 0C6, Canada
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Mannaa M, Kim KD. Effect of Temperature and Relative Humidity on Growth of Aspergillus and Penicillium spp. and Biocontrol Activity of Pseudomonas protegens AS15 against Aflatoxigenic Aspergillus flavus in Stored Rice Grains. MYCOBIOLOGY 2018; 46:287-295. [PMID: 30294490 PMCID: PMC6171444 DOI: 10.1080/12298093.2018.1505247] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 07/18/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
In this study, we evaluated the effect of different temperatures (10, 20, 30, and 40 °C) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.
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Affiliation(s)
- Mohamed Mannaa
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul, South Korea
| | - Ki Deok Kim
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul, South Korea
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Draft Genome Sequences of Bacillus megaterium KU143, Microbacterium testaceum KU313, and Pseudomonas protegens AS15, Isolated from Stored Rice Grains. GENOME ANNOUNCEMENTS 2018; 6:6/22/e00468-18. [PMID: 29853508 PMCID: PMC5981034 DOI: 10.1128/genomea.00468-18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacillus megaterium KU143, Microbacterium testaceum KU313, and Pseudomonas protegens AS15 from stored rice grains exhibited antifungal activity against Aspergillus and Penicillium spp. predominant in stored rice. Here, we report their bacterial draft genomes, which contain genes related to biotic and abiotic stress management, as well as antimicrobial and insecticidal traits.
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Mannaa M, Kim KD. Biocontrol Activity of Volatile-Producing Bacillus megaterium and Pseudomonas protegens Against Aspergillus and Penicillium spp. Predominant in Stored Rice Grains: Study II. MYCOBIOLOGY 2018; 46:52-63. [PMID: 29998033 PMCID: PMC6037079 DOI: 10.1080/12298093.2018.1454015] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 02/28/2018] [Accepted: 03/05/2018] [Indexed: 05/13/2023]
Abstract
In our previous studies, Bacillus megaterium KU143, Microbacterium testaceum KU313, and Pseudomonas protegens AS15 have been shown to be antagonistic to Aspergillus flavus in stored rice grains. In this study, the biocontrol activities of these strains were evaluated against Aspergillus candidus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum, which are predominant in stored rice grains. In vitro and in vivo antifungal activities of the bacterial strains were evaluated against the fungi on media and rice grains, respectively. The antifungal activities of the volatiles produced by the strains against fungal development and population were also tested using I-plates. In in vitro tests, the strains produced secondary metabolites capable of reducing conidial germination, germ-tube elongation, and mycelial growth of all the tested fungi. In in vivo tests, the strains significantly inhibited the fungal growth in rice grains. Additionally, in I-plate tests, strains KU143 and AS15 produced volatiles that significantly inhibited not only mycelial growth, sporulation, and conidial germination of the fungi on media but also fungal populations on rice grains. GC-MS analysis of the volatiles by strains KU143 and AS15 identified 12 and 17 compounds, respectively. Among these, the antifungal compound, 5-methyl-2-phenyl-1H-indole, was produced by strain KU143 and the antimicrobial compounds, 2-butyl 1-octanal, dimethyl disulfide, 2-isopropyl-5-methyl-1-heptanol, and 4-trifluoroacetoxyhexadecane, were produced by strain AS15. These results suggest that the tested strains producing extracellular metabolites and/or volatiles may have a broad spectrum of antifungal activities against the grain fungi. In particular, B. megaterium KU143 and P. protegens AS15 may be potential biocontrol agents against Aspergillus and Penicillium spp. during rice grain storage.
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Affiliation(s)
- Mohamed Mannaa
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul, South Korea
| | - Ki Deok Kim
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul, South Korea
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26
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Mannaa M, Kim KD. Influence of Temperature and Water Activity on Deleterious Fungi and Mycotoxin Production during Grain Storage. MYCOBIOLOGY 2017; 45:240-254. [PMID: 29371792 PMCID: PMC5780356 DOI: 10.5941/myco.2017.45.4.240] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Accepted: 11/11/2017] [Indexed: 05/05/2023]
Abstract
Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity (aw) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and aw. This review discusses the effects of temperature and aw on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.
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Affiliation(s)
- Mohamed Mannaa
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul 02841, Korea
| | - Ki Deok Kim
- Laboratory of Plant Disease and Biocontrol, Department of Biosystems and Biotechnology, Korea University, Seoul 02841, Korea
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