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1.
Int J Food Microbiol ; 358: 109404, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34563882

RESUMO

The objectives of this research were to study the effect of DMDC (0-250 ppm) on quality and shelf life of mango and passion fruit smoothie during cold storage. The correlation between microbial population (total microorganisms, yeast and mold, E. coli and S. aureus) and DMDC concentration using zero-order kinetic and first-order kinetic was also determined. In addition, the effect of DMDC compared with pasteurization (90 °C, 100 s) on quality of mixed mango and passion fruit smoothie during the cold storage (4 °C) was studied. The results showed that microbial inactivation was best-described by first-order kinetic model due to a higher coefficient of determination (R2). In addition, DMDC did not affect the decreasing trend of total soluble solid, color difference (∆E*) and total phenolic compound as compared to control during the cold storage. DMDC also hindered the increasing trend in microbial population and prevented the loss of antioxidant activity (DPPH and FRAP assays) and total flavonoid content and decreased the PPO activity as compared with the control during the cold storage. In summary, DMDC showed the potential to maintain the quality and to extend the shelf life of mango and passion fruit smoothie during cold storage.


Assuntos
Contaminação de Alimentos/análise , Armazenamento de Alimentos , Frutas/microbiologia , Mangifera , Passiflora , Temperatura Baixa , Dietil Pirocarbonato/análogos & derivados , Escherichia coli , Microbiologia de Alimentos , Mangifera/microbiologia , Passiflora/microbiologia , Staphylococcus aureus
2.
BMC Plant Biol ; 21(1): 397, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433413

RESUMO

BACKGROUND: Mandarin 'Shatangju' is susceptible to Huanglongbing (HLB) and the HLB-infected fruits are small, off-flavor, and stay-green at the maturity period. To understand the relationship between pericarp color and HLB pathogen and the effect mechanism of HLB on fruit pericarp coloration, quantitative analyses of HLB bacterial pathogens and carotenoids and also the integrative analysis of metabolome and transcriptome profiles were performed in the mandarin 'Shatangju' variety with four different color fruits, whole green fruits (WGF), top-yellow and base-green fruits (TYBGF), whole light-yellow fruits (WLYF), and whole dark-yellow fruits (WDYF) that were infected with HLB. RESULTS: the HLB bacterial population followed the order WGF > TYBGF > WLYF > WDYF. And there were significant differences between each group of samples. Regarding the accumulation of chlorophyll and carotenoid, the chlorophyll-a content in WGF was the highest and in WDYF was the lowest. The content of chlorophyll-b in WGF was significantly higher than that in other three pericarps. There were significant differences in the total content of carotenoid between each group. WGF and TYBGF pericarps were low in phytoene, γ-carotene, ß-cryptoxanthin and apocarotenal, while other kinds of carotenoids were significantly higher than those in WDYF. And WLYF was only short of apocarotenal. We comprehensively compared the transcriptome and metabolite profiles of abnormal (WGF, TYBGF and WLYF) and normal (WDYF, control) pericarps. In total, 2,880, 2,782 and 1,053 differentially expressed genes (DEGs), including 121, 117 and 43 transcription factors were identified in the three comparisons, respectively. The qRT-PCR confirmed the expression levels of genes selected from transcriptome. Additionally, a total of 77 flavonoids and other phenylpropanoid-derived metabolites were identified in the three comparisons. Most (76.65 %) showed markedly lower abundances in the three comparisons. The phenylpropanoid biosynthesis pathway was the major enrichment pathway in the integrative analysis of metabolome and transcriptome profiles. CONCLUSIONS: Synthesizing the above analytical results, this study indicated that different color pericarps were associated with the reduced levels of some carotenoids and phenylpropanoids derivatives products and the down-regulation of proteins in flavonoids, phenylpropanoids derivatives biosynthesis pathway and the photosynthesis-antenna proteins.


Assuntos
Clorofila/análise , Citrus/genética , Citrus/microbiologia , Flavonoides/análise , Frutas/microbiologia , Interações Hospedeiro-Patógeno , Liberibacter/patogenicidade , Pigmentos Biológicos , Produtos Agrícolas/genética , Produtos Agrícolas/microbiologia , Produtos Agrícolas/fisiologia , Frutas/genética , Frutas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Metaboloma , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma
3.
Nutrients ; 13(7)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371928

RESUMO

The "drunken monkey" hypothesis posits that attraction to ethanol derives from an evolutionary linkage among the sugars of ripe fruit, associated alcoholic fermentation by yeast, and ensuing consumption by human ancestors. First proposed in 2000, this concept has received increasing attention from the fields of animal sensory biology, primate foraging behavior, and molecular evolution. We undertook a review of English language citations subsequent to publication of the original paper and assessed research trends and future directions relative to natural dietary ethanol exposure in primates and other animals. Two major empirical themes emerge: attraction to and consumption of fermenting fruits (and nectar) by numerous vertebrates and invertebrates (e.g., Drosophila flies), and genomic evidence for natural selection consistent with sustained exposure to dietary ethanol in diverse taxa (including hominids and the genus Homo) over tens of millions of years. We also describe our current field studies in Uganda of ethanol content within fruits consumed by free-ranging chimpanzees, which suggest chronic low-level exposure to this psychoactive molecule in our closest living relatives.


Assuntos
Consumo de Bebidas Alcoólicas , Evolução Biológica , Exposição Dietética , Etanol/metabolismo , Fermentação , Frutas/microbiologia , Leveduras/metabolismo , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/metabolismo , Consumo de Bebidas Alcoólicas/psicologia , Alcoolismo/metabolismo , Alcoolismo/psicologia , Animais , Exposição Dietética/efeitos adversos , Etanol/efeitos adversos , Comportamento Alimentar , Frutas/metabolismo , Humanos , Pan troglodytes
4.
J Food Sci ; 86(8): 3341-3348, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34272735

RESUMO

Contamination with a variety of filamentous fungi can cause deterioration of food and agricultural products. Fungal contaminations reduce the quality and the shelf life of fresh fruits and are one of the main causes of economic loss in the global fresh fruit industry. Although chemical fungicides are effective and traditionally used to control postharvest fungal diseases, they are harmful to human health. In this context, use of RNA interference (RNAi)-based fungicides is a promising alternative strategy. Spray-induced gene silencing (SIGS) is an innovative RNAi-based approach for silencing target genes in phytopathogens. This review aims to discuss the recent findings on the use of RNAi-based fungicides to control the postharvest spoilage of fresh fruits. PRACTICAL APPLICATION: Control of postharvest fungal diseases is one of the most important strategies to make food available to consumers longer. In this sense, the external application of RNAi seems to be technologically advantageous and efficient as it helps to maintain the characteristics of plant products. In this sense, this review discussed what is possible to find in the literature regarding this new technology.


Assuntos
Agricultura , Frutas , Fungos , Doenças das Plantas , Interferência de RNA , Agricultura/métodos , Frutas/microbiologia , Fungos/efeitos dos fármacos , Fungos/genética , Doenças das Plantas/prevenção & controle , RNA/farmacologia
5.
J Plant Physiol ; 264: 153472, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34315028

RESUMO

Citrus fruit are generally confronted with various fungal diseases that cause fruit deterioration and economic loss. Salicylic acid (SA), a plant hormone, is an important signal molecule required for stimulating the disease resistance of plants. However, there has been limited information about the molecular mechanism of SA biosynthesis involving biotic stress response in citrus fruit. In the present study, an R2R3 MYB transcription factor (CsMYB96) was identified to mediate SA signaling in response to fungal diseases. The transient overexpression assay revealed that CsMYB96 contributed to the strong tolerance of citrus fruit to Penicillium italicum along with an increase in SA content; meanwhile, CsMYB96 conferred resistance to Botrytis cinerea in Arabidopsis plants. Further metabolomic profiling of stable transgenic Arabidopsis revealed that CsMYB96 participated in the regulation of various metabolism pathways and enhanced the accumulation of phenolic acids. RNA-seq analysis confirmed that overexpression of CsMYB96 activated the expression of genes involved in plant-pathogen interaction, phenylpropanoid biosynthesis, and SA signaling. Besides, CsMBY96 directly activated the transcription of calmodulin binding protein 60g (CsCBP60g), a predominant transcription factor required for the activation of SA signaling. In summary, our results reveal that CsMYB96 promotes SA biosynthesis and the accumulation of defense metabolites to enhance the fungal pathogen resistance of citrus fruit and Arabidopsis and provide new insights into the regulation of disease response.


Assuntos
Citrus sinensis/imunologia , Resistência à Doença , Frutas/microbiologia , Doenças das Plantas/imunologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis , Botrytis , Citrus sinensis/metabolismo , Citrus sinensis/microbiologia , Frutas/imunologia , Frutas/metabolismo , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas
6.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201359

RESUMO

Red pepper (Capsicum annuum, L.), is one of the most important spice plants in Korea. Overwintering pepper fruits are a reservoir of various microbial pepper diseases. Here, we conducted metagenomics (DNA sequencing) and metatranscriptomics (RNA sequencing) using samples collected from three different fields. We compared two different library types and three different analytical methods for the identification of microbiomes in overwintering pepper fruits. Our results demonstrated that DNA sequencing might be useful for the identification of bacteria and DNA viruses such as bacteriophages, while mRNA sequencing might be beneficial for the identification of fungi and RNA viruses. Among three analytical methods, KRAKEN2 with raw data reads (KRAKEN2_R) might be superior for the identification of microbial species to other analytical methods. However, some microbial species with a low number of reads were wrongly assigned at the species level by KRAKEN2_R. Moreover, we found that the databases for bacteria and viruses were better established as compared to the fungal database with limited genome data. In summary, we carefully suggest that different library types and analytical methods with proper databases should be applied for the purpose of microbiome study.


Assuntos
Bactérias/genética , Capsicum/genética , Vírus de DNA/genética , Frutas/crescimento & desenvolvimento , Metagenoma , Vírus de RNA/genética , Transcriptoma , Bactérias/classificação , Capsicum/microbiologia , Capsicum/virologia , Vírus de DNA/classificação , Frutas/microbiologia , Frutas/virologia , Vírus de RNA/classificação , Estações do Ano
7.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203436

RESUMO

The beneficial role of fungi from the Trichoderma genus and its secondary metabolites in promoting plant growth, uptake and use efficiency of macronutrients and oligo/micro-nutrients, activation of plant secondary metabolism and plant protection from diseases makes it interesting for application in environmentally friendly agriculture. However, the literature data on the effect of Trichoderma inoculation on tomato fruit quality is scarce. Commercially used tomato cultivars were chosen in combination with indigenous Trichodrema species previously characterized on molecular and biochemical level, to investigate the effect of Trichoderma on photosynthetic characteristics and fruit quality of plants grown in organic system of production. Examined cultivars differed in the majority of examined parameters. Response of cultivar Gruzanski zlatni to Trichoderma application was more significant. As a consequence of increased epidermal flavonols and decreased chlorophyll, the nitrogen balance index in leaves has decreased, indicating a shift from primary to secondary metabolism. The quality of its fruit was altered in the sense of increased total flavonoids content, decreased starch, increased Bioaccumulation Index (BI) for Fe and Cr, and decreased BI for heavy metals Ni and Pb. Higher expression of swolenin gene in tomato roots of more responsive tomato cultivar indicates better root colonization, which correlates with observed positive effects of Trichodrema.


Assuntos
Trichoderma/patogenicidade , Flavonoides/metabolismo , Frutas/microbiologia , Hypocreales/patogenicidade , Fotossíntese/fisiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/microbiologia
8.
Food Microbiol ; 99: 103797, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119092

RESUMO

Postharvest treatments with sanitizers and fungicides are applied to increase the quality, safety and shelf life of fresh produce including cantaloupes (also known as rockmelons). The primary role of sanitizers during cantaloupe washing is to prevent cross contamination of potentially pathogenic bacteria in washwater. Postharvest fungicide sprays or dips are employed to inhibit spoilage-causing fungi. While assessing the compatibility of these antimicrobials based on the measurement of active ingredients levels provides some indication of antimicrobial capacity, there is limited data on whether the interaction between these chemicals in wash water modifies their overall efficacy against relevant microorganisms. The aim of this research was to determine how chlorine- and peroxyacetic acid-based sanitizers interact with commercial guazatine- and imazalil-based fungicide formulations used on cantaloupes, and whether mixing these augments or suppresses anti-microbial activity against relevant human pathogens and spoilage fungi in wash water. The results were unpredictable: while most combinations were antimicrobial, the chlorine-based sanitizer when mixed with the guazatine-based fungicide had significantly reduced efficacy against pathogenic Salmonella spp. (~2.7 log) and the fungal spoilage organisms, Trichothecium roseum and Rhizopus stolonifera. Mixing the chlorine-based sanitizer with an imazalil-based fungicide produced a range of outcomes with antagonistic, indifferent and synergistic interactions observed for the fungal species tested. The peroxyacetic acid-based sanitizer led to indifferent interactions with the guazatine-based fungicide, while antagonism and synergy were observed when mixed with the imazalil-based fungicide. This study demonstrates that mixing postharvest agrichemicals used in the cantaloupe industry may increase the risk of microbial contamination and thereby potentially compromise food safety and quality.


Assuntos
Cucumis melo/microbiologia , Desinfetantes/farmacologia , Conservação de Alimentos/métodos , Fungicidas Industriais/farmacologia , Cloro/química , Cloro/farmacologia , Desinfetantes/química , Interações Medicamentosas , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/instrumentação , Frutas/microbiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Fungicidas Industriais/química , Guanidinas/química , Guanidinas/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Ácido Peracético/química , Ácido Peracético/farmacologia , Salmonella/efeitos dos fármacos , Salmonella/crescimento & desenvolvimento
9.
Food Microbiol ; 99: 103824, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119109

RESUMO

Rapid yeast identification is of particular importance in monitoring wine fermentation and assessing strain application in winemaking. We used MALDI-TOF MS analysis supported by 26 S rRNA gene sequence analysis and Saccharomyces-specific PCR testing to differentiate reference and field strains recovered from organic wine production facilities in Waipara, New Zealand, in which Pinot Noir wine was produced by spontaneous fermentations in the vineyard and in the winery. Strains were isolated from each of four key stages of each ferment to evaluate changes in taxonomic diversity. MALDI-TOF MS analysis was confirmed as an excellent yeast identification method, with even closely related Saccharomyces species readily distinguished. A total of 13 indigenous species belonging to eight genera were identified from Pinot Noir ferments, with taxonomic diversity generally reducing as fermentation progressed. However, differences between the taxa recovered were observed between the vineyard and winery ferments, despite the grapes used being from the same batch. Furthermore, some consistent proteomic differences between strains of S. cerevisiae, Hanseniasporum uvarum, Candida californica, Pichia membranifaciens and Starmerella bacillaris correlated with the different fermentation systems used. The high speed, low cost, taxonomic resolution and ability to characterise subtle changes in phenotype that may result from variations in environmental conditions makes MALDI-TOF analysis an attractive tool for further and wider applications in the wine industry. Such applications may include monitoring wine fermentation to actively support the consistency of high-quality wine products, and potentially for the development of such products too.


Assuntos
Técnicas de Tipagem Micológica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Vinho/microbiologia , Leveduras/isolamento & purificação , Leveduras/metabolismo , Fermentação , Frutas/microbiologia , Nova Zelândia , Vitis/microbiologia , Vinho/análise , Leveduras/química , Leveduras/classificação
10.
Food Microbiol ; 99: 103830, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119115

RESUMO

The occurrence of various foodborne disease outbreaks linked to the consumption of cucumbers worldwide in the last years raised concerns regarding the survival ability of foodborne pathogens on this food matrix. This work aimed at evaluating and quantifying the survival of Escherichia coli O157:H7 and Salmonella spp. on cucumber surfaces. Cucumbers were inoculated with a 5-strain cocktail of each microorganism and kept at 25 °C. The survival ability of two green fluorescent protein (GFP) labelled Salmonella strains inoculated individually on cucumbers was also evaluated. The inoculated areas were swabbed at different time intervals (maximum of 72 h) and cells were enumerated by plate count method (log CFU/cm2). The population of both pathogens decreased significantly on cucumber surfaces over time. E. coli O157:H7 could only be recovered up to 8 h while Salmonella spp. could be detected up to 24 h. The GFP-labelled Salmonella strains showed similar behaviour on cucumbers compared to the evaluated Salmonella cocktail. Survival kinetic parameters were estimated by fitting the Weibull model to the survival data. The data obtained in this study indicate that despite of the rapid decrease on concentrations of both pathogens evaluated on cucumbers surfaces, strategies to avoid their contamination during the supply chain as well as proper cleaning and disinfection protocols must be put forward to mitigate both E. coli O57:H7 and Salmonella on cucumbers and therefore, to decrease the exposure of consumers to microbial hazards and to avoid cross-contamination events during distribution, retail and in domestic environments.


Assuntos
Cucumis sativus/microbiologia , Escherichia coli O157/crescimento & desenvolvimento , Salmonella/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Frutas/microbiologia , Viabilidade Microbiana
11.
Food Microbiol ; 99: 103833, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119117

RESUMO

Fruits and vegetables consumed fresh or as minimally-processed produce, have multiple benefits for our diet. Unfortunately, they bring a risk of food-borne diseases, for example salmonellosis. Interactions between Salmonella and crop plants are indeed a raising concern for the global health. Salmonella uses multiple strategies to manipulate the host defense system, including plant's defense responses. The main focus of this review are strategies used by this bacterium during the interaction with crop plants. Emphasis was put on how Salmonella avoids the plant defense responses and successfully colonizes plants. In addition, several factors were reviewed assessing their impact on Salmonella persistence and physiological adaptation to plants and plant-related environment. The understanding of those mechanisms, their regulation and use by the pathogen, while in contact with plants, has significant implication on the growth, harvest and processing steps in plant production system. Consequently, it requires both the authorities and science to advance and definite methods aiming at prevention of crop plants contamination. Thus, minimizing and/or eliminating the potential of human diseases.


Assuntos
Plantas/microbiologia , Salmonella/crescimento & desenvolvimento , Microbiologia de Alimentos , Frutas/microbiologia , Humanos , Plantas/genética , Plantas/imunologia , Salmonella/genética , Salmonella/isolamento & purificação , Infecções por Salmonella/microbiologia , Verduras/microbiologia
12.
Food Chem ; 362: 130150, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34082295

RESUMO

Colletotrichum has been identified as responsible for the "dried fruit" disease in açaí (Euterpe oleracea). Besides concern for açaí pulp quality control, the characterization of Colletotrichum has been difficult, which has motivated the search for chemical markers in the Volatile Organic Compounds (VOCs) profile for use as a tool in the identification of açaí pulp contaminated by the fungus. Extracted VOCs by Headspace - Solid Phase Micro Extraction (HS-SPME) were identified through gas chromatography mass spectrometry (GC-MS). From GC-MS analyzes 26 VOCs were identified, with a predominance of the terpenoids. Chemometrically, menthol and menthone were assigned as potential markers of the genus. The analysis of VOCs in açaí pulps contaminated by Colletotrichum under different cultivation conditions enabled the detection of menthone. This result illustrated the selectivity of the culture medium and the potential of this tool for use in the quality control of açaí pulp.


Assuntos
Colletotrichum/química , Euterpe/microbiologia , Compostos Orgânicos Voláteis/análise , Quimioinformática/métodos , Colletotrichum/isolamento & purificação , Colletotrichum/patogenicidade , Euterpe/química , Qualidade dos Alimentos , Frutas/química , Frutas/microbiologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Doenças das Plantas/microbiologia , Controle de Qualidade , Microextração em Fase Sólida/métodos
13.
BMC Plant Biol ; 21(1): 249, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059002

RESUMO

BACKGROUND: Walnut anthracnose induced by Colletotrichum gloeosporioides is a disastrous disease affecting walnut production. The resistance of walnut fruit to C. gloeosporioides is a highly complicated and genetically programmed process. However, the underlying mechanisms have not yet been elucidated. RESULTS: To understand the molecular mechanism underlying the defense of walnut to C. gloeosporioides, we used RNA sequencing and label-free quantitation technologies to generate transcriptomic and proteomic profiles of tissues at various lifestyle transitions of C. gloeosporioides, including 0 hpi, pathological tissues at 24 hpi, 48 hpi, and 72 hpi, and distal uninoculated tissues at 120 hpi, in anthracnose-resistant F26 fruit bracts and anthracnose-susceptible F423 fruit bracts, which were defined through scanning electron microscopy. A total of 21,798 differentially expressed genes (DEGs) and 1929 differentially expressed proteins (DEPs) were identified in F26 vs. F423 at five time points, and the numbers of DEGs and DEPs were significantly higher in the early infection stage. Using pairwise comparisons and weighted gene co-expression network analysis of the transcriptome, we identified two modules significantly related to disease resistance and nine hub genes in the transcription expression gene networks. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of the DEGs and DEPs revealed that many genes were mainly related to immune response, plant hormone signal transduction, and secondary metabolites, and many DEPs were involved in carbon metabolism and photosynthesis. Correlation analysis between the transcriptome data and proteome data also showed that the consistency of the differential expression of the mRNA and corresponding proteins was relatively higher in the early stage of infection. CONCLUSIONS: Collectively, these results help elucidate the molecular response of walnut fruit to C. gloeosporioides and provide a basis for the genetic improvement of walnut disease resistance.


Assuntos
Colletotrichum , Juglans/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Frutas/genética , Frutas/microbiologia , Juglans/genética , Proteoma , Transcriptoma
14.
Int J Biol Macromol ; 183: 2100-2108, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34102235

RESUMO

Effect of edible coatings of gum Arabic, carrageenan and xanthan gum containing lemon grass essential oil 1% w/v on postharvest quality of strawberry was studied under refrigeration for a period of 12 days. Results showed all the three coatings maintained fruit quality parameters during storage compared to control. Among all the coatings, carrageenan coated fruits showed delayed weight loss (10.1 to 8%), decay percentage (78.42 to 14.29%), retained ascorbic acid (0.15 to 0.27 g kg-1), antioxidant activity (18.17 to 25.85%), firmness (9.07 to 12.43 N), L* (32.38 to 40.42), a* (16.08 to 17.22) and b* (27.36 to 33.54). Carrageenan gum also showed lowest cellulase activity (0.03 units h-1 mg protein-1), pectin methylesterase activity (1.13 A620 min-1 mg protein-1) and ß-galactosidase activity (0.51 µmol min-1 mg protein-1), while showed maximum reduction in polygalacturonase activity (0.07 units h-1 mg protein-1) at the end of storage. Carrageenan gum was found effective in retention of anthocyanins and phenolic compounds during storage. Coatings loaded with antimicrobial agent inhibited psychrophilic bacteria, yeast and mold growth. It is concluded that carrageenan gum could better retain strawberry quality up to 12 days under refrigeration.


Assuntos
Anti-Infecciosos/química , Carragenina/química , Filmes Comestíveis , Embalagem de Alimentos , Conservação de Alimentos , Fragaria/enzimologia , Frutas/enzimologia , Goma Arábica/química , Óleos Vegetais/química , Polissacarídeos Bacterianos/química , Antocianinas/metabolismo , Anti-Infecciosos/farmacologia , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Celulase/metabolismo , Cymbopogon , Microbiologia de Alimentos , Armazenamento de Alimentos , Fragaria/microbiologia , Frutas/microbiologia , Fenóis/química , Óleos Vegetais/isolamento & purificação , Óleos Vegetais/farmacologia , Poligalacturonase/metabolismo , Refrigeração , Fatores de Tempo , beta-Galactosidase/metabolismo
15.
Acta Biochim Pol ; 68(2): 301-307, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33969671

RESUMO

The genus Alicyclobacillus comprises a group of Gram-positive, thermo-acidophilic bacteria that are capable of producing highly resistant endospores during unfavorable environmental conditions. The members of this genus inhabit natural environments, including hot springs and soils. The main reason behind the spoilage of final commercial fruit products by Alicyclobacillus is the contamination of fruits with soil at the time of harvesting. Some of the Alicyclobacillus species, including Alicyclobacillus acidoterrestris, are categorized as spoilage bacteria due to their ability to produce off-flavor compounds (e.g., guaiacol and halophenols) that adversely affect the taste and aroma of beverages. In our study, Alicyclobacillus species were isolated from Polish orchard soils and fruits and were subjected to 16S rDNA sequencing. The results of the analysis showed that the isolated strains belonged to A. acidoterrestris and Alicyclobacillus fastidiosus species. All the three isolated strains of A. fastidiosus (f1, f2, f3) exhibited similar morphological and biochemical properties as the strain described in the literature. However, these isolated strains were able to produce guaiacol at temperatures of 20°C, 25°C, and 45°C. Thus, the strains of A. fastidiosus discovered in the present study can be included in the group of spoilage species as they possessed the gene responsible for the production of guaiacol.


Assuntos
Alicyclobacillus/genética , Alicyclobacillus/isolamento & purificação , Frutas/microbiologia , Guaiacol/isolamento & purificação , Microbiologia do Solo , Alicyclobacillus/classificação , Bebidas/microbiologia , DNA Bacteriano/genética , Microbiologia de Alimentos/métodos , Frutas/química , Sucos de Frutas e Vegetais/microbiologia , Guaiacol/metabolismo , Polônia , RNA Ribossômico 16S/genética , Esporos Bacterianos/isolamento & purificação , Temperatura
16.
Carbohydr Polym ; 266: 118176, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34044916

RESUMO

Bacterial nanocellulose production is gaining popularity owing to its applications in food, cosmetics and medical industry. Three Acetobacter strains isolated from organic waste and fermented tea were identified using 16S rDNA sequencing and their ability to produce nanocellulose was studied. Strain isolated from Kombucha has 99% homology with Komagataeibacter rhaeticus DSM 16663 T. This is the first report where nanocellulose productivity of this strain with different carbon sources such as glucose, glycerol, fructose and sucrose has been studied. 1% glycerol was found to be optimal concentration, with up to 69% of the utilized carbon converted to nanocellulose. Maximum productivity of 4.5 g/L of bacterial nanocellulose was obtained. Average nitrogen and phosphorus consumption rate was 45 mg/L/day each. Physical properties such as crystallinity, fibril dimensions, and glass transition temperature were studied. Bacterial cellulose was 80% crystalline when glycerol and glucose were used as carbon source and 73% for fructose and sucrose. Renewable materials such as bacterial cellulose with their unique properties are the future for applications in the field of cosmetics, composite and wound care.


Assuntos
Celulose/biossíntese , Frutas/microbiologia , Chá de Kombucha/microbiologia , Nanoestruturas/química , Acetobacteraceae/metabolismo , Separação Celular , Celulose/química , Glucose/metabolismo , Glicerol/metabolismo , Resíduos Sólidos
17.
Arch Microbiol ; 203(7): 4025-4032, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34041558

RESUMO

This study examined the antibacterial activity of the biological pesticide Liangguoan against Staphylococcus aureus and Escherichia coli as a potential replacement for chemical pesticide use in the fruit and vegetable industry. We measured the minimum inhibitory concentration and observed the changes in bacterial morphology, mortality, conductivity, nucleic acid content, and ATP content in response to the bactericide. The minimum inhibitory concentration of Liangguoan was 20 mg/mL for S. aureus and 40 mg/mL for E. coli. After treatment with Liangguoan, the mortality rates of S. aureus and E. coli reached 78.3% and 63.7%, respectively. We observed that the cells were scattered and that the cell morphology was altered in that the cells shortened. The interconnection effect and ATP content decreased, whereas cell conductivity and the nucleic acid content increased. In summary, Liangguoan inhibited S. aureus and E. coli by destroying their cell structure and disrupting their metabolism.


Assuntos
Escherichia coli , Extratos Vegetais , Staphylococcus aureus , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Frutas/microbiologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Verduras/microbiologia
18.
Arch Microbiol ; 203(7): 4033-4040, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34041559

RESUMO

Pitaya fruit canker is an important disease in pitaya production. Facilitating resistance through the application of biological control principles is a promising alternative to traditional control strategies. This study evaluated the induced resistance of Penicillium rolfsii, numbered Y17 isolated from papaya leaves in pitaya fruit, and evaluated the activity of the defense enzymes, total antioxidant capacity (T-AOC), and malondialdehyde (MDA) content of the treated fruit. The results demonstrate that treatment with Y17 effectively induced resistance of pitaya fruit to canker disease caused by Neoscytalidium dimidiatum, with an inhibition rate of 70.87%. In addition, Y17 notably improved the activities of peroxidase, catalase, and polyphenol oxidase as well as the T-AOC of the treated samples. Y17 treatment reduced the MDA content in these fruits. Taken together, our results suggest that Y17 treatment could trigger pitaya fruit defense responses and effectively induce resistance to fruit canker disease.


Assuntos
Cactaceae , Carica , Frutas , Interações Microbianas , Penicillium , Ascomicetos , Cactaceae/microbiologia , Carica/microbiologia , Endófitos/fisiologia , Microbiologia de Alimentos , Frutas/microbiologia , Interações Microbianas/fisiologia , Penicillium/fisiologia , Controle Biológico de Vetores
19.
Artigo em Inglês | MEDLINE | ID: mdl-34043492

RESUMO

Rhodotorula mucilaginosa is an antagonistic yeast for which our research team has recently reported interesting biocontrol activities against blue mould decay of apples and a strong ability to decrease the patulin concentration in vivo. However, the possible mechanisms of patulin degradation by R. mucilaginosa and the toxicity of patulin degradation products remain unclear. In this study, the effect of R. mucilaginosa on patulin degradation and toxicity of degradation products were investigated, the results showed that viable cells of R. mucilaginosa are essential to patulin degradation. Also, R. mucilaginosa eliminated patulin without adsorbing it through its cell wall. The extracellular metabolites of R. mucilaginosa stimulated by patulin showed little degradation activity for patulin. Cycloheximide addition into the medium significantly decreased the patulin degradation capacity of R. mucilaginosa cells. The main patulin degradation product by R. mucilaginosa was ascladiol, which was proved non-toxic to human hepatoma (HepG2) cells at 0.625-10 g/mL. Furthermore, toxicological analysis using a confocal laser scanning microscope revealed that the degradation product induced cellular apoptosis to a lesser extent than patulin itself. This result offers an innovative method to detoxify patulin and limit the risks of patulin in fruits and vegetables using R. mucilaginosa.


Assuntos
Fungos/metabolismo , Furanos/toxicidade , Patulina/metabolismo , Rhodotorula/metabolismo , Cicloeximida/metabolismo , Aditivos Alimentares/metabolismo , Contaminação de Alimentos , Frutas/microbiologia , Fungos/crescimento & desenvolvimento , Células Hep G2 , Humanos , Malus/microbiologia , Metaboloma , Medição de Risco
20.
Int J Food Microbiol ; 348: 109224, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-33965694

RESUMO

ε-Poly-l-lysine (ε-PL) is a natural antimicrobial poly-cationic peptide widely applied as a natural preservative in the food industry, whereas its application in preventing postharvest loss of fruit was largely absent. This study investigated the antifungal activity of ε-PL and determined the possible mechanisms involved. The in vivo results indicated that 500 mg L-1 exogenous ε-PL treatment significantly inhibited black spot rot in apple, jujube, and tomato. The lesion diameter inhibition rate was range from 20.11% to 29.09% by 500 mg L-1 ε-PL treatment. ε-PL exerts antifungal activity against A. alternata in vitro, the half-inhibition concentration is 160.1 mg L-1. ε-PL induced morphology and ultrastructure change on the pathogen, which resulted in the inhibition of A. alternata. This was accomplished by disturbing pathogen membrane integrity and functionality. The fluorometric assay confirmed that ε-PL induced endogenous reactive oxygen species formation and accumulation in A. alternata and the elicited severe lipid peroxidation that caused membrane lesions. Further, ε-PL treatment enhanced the expression of genes involved in antioxidant metabolism and pathogenesis-related responses in apple fruit. These findings illustrated that ε-PL exhibits multifaceted antifungal activity by the direct effect on the pathogen as well as induce host defense responses. ε-PL may be conducive as a promising alternative for Alternaria rot management.


Assuntos
Alternaria/efeitos dos fármacos , Antifúngicos/farmacologia , Membrana Celular/efeitos dos fármacos , Frutas/microbiologia , Polilisina/farmacologia , Antioxidantes/metabolismo , Lycopersicon esculentum/microbiologia , Malus/microbiologia , Testes de Sensibilidade Microbiana , Ziziphus/microbiologia
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