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Applied Microbiology and Biotechnology Feb 2024Aureobasidium is omnipresent and can be isolated from air, water bodies, soil, wood, and other plant materials, as well as inorganic materials such as rocks and marble.... (Review)
Review
Aureobasidium is omnipresent and can be isolated from air, water bodies, soil, wood, and other plant materials, as well as inorganic materials such as rocks and marble. A total of 32 species of this fungal genus have been identified at the level of DNA, of which Aureobasidium pullulans is best known. Aureobasidium is of interest for a sustainable economy because it can be used to produce a wide variety of compounds, including enzymes, polysaccharides, and biosurfactants. Moreover, it can be used to promote plant growth and protect wood and crops. To this end, Aureobasidium cells adhere to wood or plants by producing extracellular polysaccharides, thereby forming a biofilm. This biofilm provides a sustainable alternative to petrol-based coatings and toxic chemicals. This and the fact that Aureobasidium biofilms have the potential of self-repair make them a potential engineered living material avant la lettre. KEY POINTS: •Aureobasidium produces products of interest to the industry •Aureobasidium can stimulate plant growth and protect crops •Biofinish of A. pullulans is a sustainable alternative to petrol-based coatings •Aureobasidium biofilms have the potential to function as engineered living materials.
Topics: Aureobasidium; Biofilms; Calcium Carbonate; Crops, Agricultural; Gasoline
PubMed: 38349550
DOI: 10.1007/s00253-024-13025-5 -
Bioresource Technology Oct 2023Pullulan is an exopolysaccharide produced by Aureobasidium pullulans, with interesting characteristics which lead to its application in industries such as... (Review)
Review
Pullulan is an exopolysaccharide produced by Aureobasidium pullulans, with interesting characteristics which lead to its application in industries such as pharmaceuticals, cosmetics, food, and others. To reduce production costs for industrial applications, cheaper raw materials such as lignocellulosic biomass can be utilized as a carbon and nutrient source for the microbial process. In this study, a comprehensive and critical review was conducted, encompassing the pullulan production process and the key influential variables. The main properties of the biopolymer were presented, and different applications were discussed. Subsequently, the utilization of lignocellulosics for pullulan production within the framework of a biorefinery concept was explored, considering the main published works that deal with materials such as sugarcane bagasse, rice husk, corn straw, and corn cob. Next, the main challenges and future prospects in this research area were highlighted, indicating the key strategies to favor the industrial production of pullulan from lignocellulosic biomasses.
Topics: Cellulose; Biomass; Fermentation; Saccharum
PubMed: 37423546
DOI: 10.1016/j.biortech.2023.129460 -
Life (Basel, Switzerland) Dec 2023Consumers today seek safe functional foods with proven health-promoting properties. Current evidence shows that a healthy diet can effectively alleviate oxidative stress...
Consumers today seek safe functional foods with proven health-promoting properties. Current evidence shows that a healthy diet can effectively alleviate oxidative stress levels and reduce inflammatory markers, thereby preventing the occurrence of many types of cancer, hypertension, and cardiovascular and neurological pathologies. Nevertheless, as fruits and vegetables are mainly consumed fresh, they can serve as vectors for the transmission of pathogenic microorganisms associated with various disease outbreaks. As a result, there has been a surge in interest in the microbiome of fruits and vegetables. Therefore, given the growing interest in sweet cherries, and since their microbial communities have been largely ignored, the primary purpose of this study is to investigate their culturome at various maturity stages for the first time. A total of 55 microorganisms were isolated from sweet cherry fruit, comprising 23 bacteria and 32 fungi species. Subsequently, the selected isolates were molecularly identified by amplifying the 16S rRNA gene and ITS region. Furthermore, it was observed that the communities became more diverse as the fruit matured. The most abundant taxa included and among the bacteria, and , , and among the fungi.
PubMed: 38137924
DOI: 10.3390/life13122323 -
Microorganisms Aug 2023is a tea leaf moth that is considered one of the most destructive pests of (tea plant). Several recent studies have shown that many insects acquire part of the...
is a tea leaf moth that is considered one of the most destructive pests of (tea plant). Several recent studies have shown that many insects acquire part of the microbiome from their host and soil, but the pattern and diversity of their microbiome have not been clearly demonstrated. The present study aimed to investigate the bacterial and fungal communities present in the rhizospheric soil and leaf of tea plant compared to the gut of tea moth at different developmental stages (larvae, pupae, adult female and male) using Illumina MiSeq technology. Alpha diversity (Shannon index) showed higher ( < 0.05) bacterial and fungal diversity in soil samples than in leaf and tea moth larvae, pupae, and adult gut samples. However, during different developmental stages of tea moth, bacterial and fungal diversity did not differ ( > 0.05) between larvae, pupae, female, and male guts. Beta diversity also revealed more distinct bacterial and fungal communities in soil and leaf samples compared with tea moth gut samples, which had a more similar microbiome. Furthermore, Proteobacteria, Firmicutes, and Tenericutes were detected as the dominant bacterial phyla, while Ascomycota, Basidiomycota, and Mortierellomycota were the most abundant fungal phyla among all groups, but their relative abundance was comparatively higher ( < 0.05) in soil and leaf samples compared to tea moth gut samples. Similarly, , , and were the top three bacterial genera, while , , and were the top three fungal genera, and their relative abundance varied significantly ( < 0.05) among all groups. The KEGG analysis also revealed significantly higher ( < 0.5) enrichment of the functional pathways of bacterial communities in soil and leaf samples than in tea moth gut samples. Our study concluded that the bacterial and fungal communities of soil and tea leaves were more diverse and were significantly different from the tea moth gut microbiome at different developmental stages. Our findings contribute to our understanding of the gut microbiota of the tea moth and its potential application in the development of pest management techniques.
PubMed: 37764032
DOI: 10.3390/microorganisms11092188 -
Microorganisms Aug 2023Airborne fungal spores constitute an important type of bioaerosol and are responsible for a number of negative effects on human health, including respiratory diseases...
Airborne fungal spores constitute an important type of bioaerosol and are responsible for a number of negative effects on human health, including respiratory diseases and allergies. We investigated the diversity and concentration of culturable airborne fungi on pedestrian bridges in Tianjin, China, using an HAS-100B air sampler. We compared the airborne fungal communities at the top central area of the selected pedestrian bridges and along the corresponding sidewalk, at ground level. A total of 228 fungal strains belonging to 96 species and 58 genera of Ascomycota (68.86%), Basidiomycota (30.26%), and Mucoromycota (0.88%) were isolated and identified using morphological and molecular analysis. was the dominant genus (20.61%), followed by (11.48%), (6.14%), (5.70%), and (4.82%). was the most frequently occurring fungal species (6.58%), followed by (5.26%), sp. (4.82%), (4.39%), and (3.95%). The recorded fungal concentration ranged from 10 to 180 CFU/m. Although there was no significant difference in the distribution and abundance of the dominant airborne fungal taxa between the two investigated bridges' sites, numerous species detected with a low percentage of abundance belonging to well-known pathogenic fungal genera, including , , , , , and , were exclusively present in one of the two sites. The relative humidity showed a stronger influence compared to the temperature on the diversity and concentration of airborne fungi in the investigated sites. Our results may provide valuable information for air quality monitoring and for assessing human health risks associated with microbial pollution.
PubMed: 37630657
DOI: 10.3390/microorganisms11082097 -
World Journal of Microbiology &... Jun 2024Liamocins, a group of high-density glycolipids, are only produced by certain strains of the yeast-like fungi in the genus Aureobasidium. Until now, few studies have...
Liamocins, a group of high-density glycolipids, are only produced by certain strains of the yeast-like fungi in the genus Aureobasidium. Until now, few studies have focused on the surfactant properties of liamocins produced from the highly diverse tropical strains of Aureobasidium. Therefore, the aims of this research were to screen the liamocin production from tropical strains of Aureobasidium spp. and to characterize their surfactant properties. A total of 41 strains of Thai Aureobasidium spp. were screened for their ability to produce liamocins, and the products were detected using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thin-layer chromatography. Of those strains, 30 strains of Aureobasidium spp. tested were found to produce liamocins with yields ranging from 0.53 to 10.60 g/l. The nature of all crude liamocins was heterogeneous, with different compositions and ratios depending on the yeast strain. These liamocins exhibited relatively high emulsifying activity against vegetable oils tested, with an emulsification index of around 40-50%; the emulsion stability of some liamocins was up to 30 days. The obtained critical micelle concentration values were varied, with those of liamocins produced from A. pullulans, A. melanogenum and A. thailandense falling in ranges from 7.70 to 119.78, 10.73 to > 1,000, and 68.56 to > 1,000 mg/l, respectively. The emulsification activity of liamocins was higher than that of the analytical grade rhamnolipids. These compounds showed strong surface tension reduction in a sodium chloride concentration range of 2-12% (w/v), pH values between 3 and 7, and temperatures between 4 and 121 °C. This is the first report of liamocins produced by A. thailandense.
Topics: Glycolipids; Aureobasidium; Surface-Active Agents; Thailand; Chromatography, Thin Layer; Plant Oils; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Emulsifying Agents; Emulsions
PubMed: 38914906
DOI: 10.1007/s11274-024-04058-z -
International Journal of Biological... Jul 2023Poly (β-L-malic acid) (PMLA) is attracting industrial interest for its potential application in medicine and other industries, whose functions primarily depend upon its...
Poly (β-L-malic acid) (PMLA) is attracting industrial interest for its potential application in medicine and other industries, whose functions primarily depend upon its molecular size and chemical structure. Up to now, the fractionation and characterization of PMLA produced by Aureobasidium spp. were still unclear. In this study, the product from A. melanogenum ipe-1 was effectively fractionated using 300 and 50 kDa membranes. During the filtration, the mechanisms of membrane fouling were illegible since the PMLA can both reject and permeate the membrane, while the main fouling mechanism varied between standard blocking and complete blocking during the diafiltration. After fractionation, 14.0, 8.4 and 77.6 % of the PMLAs with Ms of 75,134, 21,344 and 10,056 Da were distributed in the 300 kDa retentate after diafiltrating, 50 kDa retentate after diafiltrating, and the 50 kDa permeate, respectively. The M/Ms of the PMLAs were 4.12, 1.92, and 1.12 in the three fractions. Based on characteristic spectra of NMR, HPLC and FTIR, the product was not usual L-malic acid monomers, but glucose-terminated PMLA. The glucose was located at the terminal hydroxyl of PMLA. These results would serve as a valuable guide for process design and practical operation in subsequent industrial application.
Topics: Aureobasidium; Polymers; Fermentation; Malates; Poly A
PubMed: 37182630
DOI: 10.1016/j.ijbiomac.2023.124720 -
Natural Product Research Jul 2023Mannans has been attracted the interest in various sectors due to its promising applications. The low toxicity of mannans allows for their use in cosmetics,...
Mannans has been attracted the interest in various sectors due to its promising applications. The low toxicity of mannans allows for their use in cosmetics, pharmaceutical, and biomedical industries. In this study, the α-D-mannan extraction conditions from by alkaline extraction were optimized using a Box-Behnken design (BBD). The effect of temperature (°C), pH and extraction time (hours) on the yield of α-mannan was investigated. The conditions that produced the highest yield (26%) were a temperature of 92 °C, extraction time of 3 h and pH 13. In addition, the α-D-mannan structure was confirmed by methylation analysis, 1D and 2D NMR spectroscopic analysis, and GC-MS.
Topics: Mannans; Temperature; Magnetic Resonance Spectroscopy
PubMed: 35086400
DOI: 10.1080/14786419.2022.2029859 -
Food Research International (Ottawa,... Nov 2023The grapevine and vinification microbiota have a strong influence on the characteristics of the produced wine. Currently we have a good understanding of the role of...
Vineyard-mediated factors are still operative in spontaneous and commercial fermentations shaping the vinification microbial community and affecting the antioxidant and anticancer properties of wines.
The grapevine and vinification microbiota have a strong influence on the characteristics of the produced wine. Currently we have a good understanding of the role of vineyard-associated factors, like cultivar, vintage and terroir in shaping the grapevine microbiota. Notwithstanding, their endurance along the vinification process remains unknown. Thus, the main objective of our study was to determine how these factors influence (a) microbial succession during fermentation (i.e., bacterial and fungal) and (b) the antioxidant, antimutagenic and anticancer potential of the produced wines. These were evaluated under different vinification strategies (i.e., spontaneous V1, spontaneous with preservatives V2, commercial V3), employed at near full-scale level by local wineries, for two cultivars (Roditis and Sideritis), two terroir types, and two vintages. Cultivar and vintage were strong and persistent determinants of the vinification microbiota, unlike terroir whose effect became weaker from the vineyard, and early fermentation stages, where non-Saccharomyces yeasts, filamentous fungi (i.e., Aureobasidium, Cladosporium, Lachancea, Alternaria, Aspergillus, Torulaspora) and acetic acid bacteria (AAB) (Gluconobacter, Acetobacter, Komagataeibacter) dominated, to late fermentation stages where Saccharomyces and Oenococcus become prevalent. Besides vineyard-mediated factors, the vinification process employed was the strongest determinant of the fungal community compared to the bacterial community were effects varied per cultivar. Vintage and vinification type were the strongest determinants of the antioxidant, antimutagenic and anticancer potential of the produced wines. Further analysis identified significant positive correlations between members of the vinification microbiota like the yeasts Torulaspora debrueckii and Lachancea quebecensis with the anticancer and the antioxidant properties of wines in both cultivars. These findings could be exploited towards a microbiota-modulated vinification process to produce high-quality wines with desirable properties and enhanced regional identity.
Topics: Wine; Vitis; Antioxidants; Farms; Fermentation; Microbiota; Torulaspora; Acetic Acid
PubMed: 37803700
DOI: 10.1016/j.foodres.2023.113359 -
A critical review on valorization of food processing wastes and by-products for pullulan production.Journal of Food Science and Technology Aug 2023Pullulan is a commercially available exopolymer biosynthesized by supplemented with nitrogen, carbon and other vital components through submerged and solid-state... (Review)
Review
Pullulan is a commercially available exopolymer biosynthesized by supplemented with nitrogen, carbon and other vital components through submerged and solid-state fermentation. These nutrients are very expensive and it raises the cost for the production of pullulan. Hence, the need of alternative cost-effective raw materials for its production is a prerequisite. Owing to its unique physicochemical features, pullulan has various applications in the food, pharmacological, and biomedical domains. Food industrial wastes generate a considerable number of by-products which accumulates and has a negative influence on the environment. These by-products are made up of proteins, carbohydrates, and other components, can be employed as substrates for the production of pullulan. The present review briefs on the pullulan production using food processing waste and by-products and the elements that impact it. It provides an insight into versatile applications of pullulan in food industries. Various challenges and future prospects in the field of research on pullulan production have been uncovered.
PubMed: 37273573
DOI: 10.1007/s13197-022-05490-5