Mycobiota in the Carposphere of Sour and Sweet Cherries and Antagonistic Features of Potential Biocontrol Yeasts

Abstract

Sour cherries (Prunus cerasus L.) and sweet cherries (P. avium L.) are economically important fruits with high potential in the food industry and medicine. In this study, we analyzed fungal communities associated with the carposphere of sour and sweet cherries that were freshly harvested from private plantations and purchased in a food store. Following DNA isolation, a DNA fragment of the ITS2 rRNA gene region of each sample was individually amplified and subjected to high-throughput NGS sequencing. Analysis of 168,933 high-quality reads showed the presence of 690 fungal taxa. Investigation of microbial ASVs diversity revealed plant-dependent and postharvest handling-affected fungal assemblages. Among the microorganisms inhabiting tested berries, potentially beneficial or pathogenic fungi were documented. Numerous cultivable yeasts were isolated from the surface of tested berries and characterized by their antagonistic activity. Some of the isolates, identified as Aureobasidium pullulans, Metschnikowia fructicola, and M. pulcherrima, displayed pronounced activity against potential fungal pathogens and showed attractiveness for disease control.

Volatiles Produced by Yeasts Related to Prunus avium and P. cerasus Fruits and Their Potentials to Modulate the Behaviour of the Pest Rhagoletis cerasi Fruit Flies

“…Yeast species have been isolated from sweet cherry (Prunus avium L.) and sour cherry (Prunus cerasus L.) (Rosales: Rosaceae) fruits collected during June-July of 2018-2020 from private plantations located in the Vilnius region (GPS coordinates: 54 • 45 08.2 N, 25 • [16]. Generally, cultivable yeasts are isolated by direct rinsing of fruits with MD medium (2% dextrose, 1% (NH4)2SO4, 0.09% KH2PO4, 0.05% MgSO4, 0.023% K2HPO4, 0.01% NaCl, 0.01% CaCl 2 ) or by applying fermentation-based enrichment.…”

“…After cultivation on YPD-agar plates (1% yeast extract, 1% peptone, 2% dextrose, 2% agar), morphologically distinct colonies proceeded molecular analysis. For taxonomic identification of the isolates, the ITS1-5.8S rDNA-ITS2 region or D1/D2 region of 26S rDNA were PCR-amplified as described in Stanevičien ė et al [16]. To assess their taxonomic position, the resolved sequences were compared with those available in the current version of the GenBank database at the National Centre for Biotechnology Information (NCBI) (Table A1).…”

“…Compounds indicated by star mark were excluded from multivariate analysis, 2 MHMP-methyl 2-hydroxy-4-methylpentanoate,3 CAS No-chemical abstract service number,4 RI-retention index (DB-Wax fused silica capillary column 30 m × 0.25 mm i.d., 0.25 µm film thickness),5 GR-group of a chemical compound,6 ES-ester,7 AL-aldehyde,8 OH-alcohol,9 KT-ketone,10 AR-aromatic,11 CN-isothiocyanoate,12 PY-pyrazine,13 FA-fatty acid,14 FU-furane,15 sulphide,16 TE-terpenoid,17 IM-imine,18 LA-lactone,19 mean ± standard error of the mean (means are the absolute amounts expressed as areas under the chromatographic peaks and have to be read as numbers times 1000),20 ns-not significantly different compare to control (Nonparametric Mann-Whitney U test, p < 0.05), three different isolates of each yeast species have been used; control samples were obtained by collecting background volatiles from YPD-agar plates without yeast.…”

Food Microbial Diversity

“…In these articles the microbial diversity of several foods including the plant-based foods (cherries and olives) [9][10][11], foods of animal origin (meat and dairy products) [12,13] and drinks/beverages (wine and kombucha) [14][15][16] was monitored and/or the microbial physiology and properties were exploited [11,14,16]. In these studies, the microbial characterization was performed through the application of molecular approaches to identify the isolated microbial species [12,13] and analyses of the massive sequences resulting from culture-independent approaches [9][10][11]13,15]. The mapping of microorganisms present in a particular type of food through this collection of articles revealed important information related to the quality and safety of the studied products.…”

“…In brief, the microbial consortium that comprises the starter cultures used for the production of Kombucha in several brewers located in North America was explored [15]. Moreover, the technological, spoilage and pathogenic mycobiota present on cherries was characterized [11]. Similarly, Madoroba et al [13] collected microbial quality and safety data from meat and meat products purchased from South Africa.…”