Anisotropic Aerogels with Excellent Mechanical Resilience and Thermal Insulation from Pleurotus eryngii Fungus

Biomass aerogels with superior sustainability, high compressibility, and resilience are highly attractive for diverse technological applications. Anisotropic fungus aerogels derived from natural Pleurotus eryngii with excellent compressibility and resilience are obtained through a facile and environmentally friendly top-down approach. The preserved alignment of polysaccharide fibers inside fungus aerogels leads to remarkable anisotropic mechanical and thermal insulation properties. The cross-links generated via facile chemical modification endow fungus aerogels with excellent compressibility and resilience (deformation recovery rate of ≥96% even when the compression strain is ≥90%). Moreover, via a facile hydrophobic silanization treatment, the elastic aerogels can be endowed with excellent superhydrophobicity and water resistance. It is anticipated that this facile and sustainable strategy will provide technical support for scalable production of fungus-based aerogels with excellent compressibility and resilience, unique thermal anisotropy, and superior renewability. Meanwhile, the newly developed fungus aerogels will have broad applications in durable thermal insulation and acoustic absorption materials.     

Association between Downstream Taste Signaling Genes,Oral Microbiome,and Severe Early Childhood Caries

Polymorphisms in taste receptor genes have been shown to play a role in early childhood caries (ECC), a multifactorial, biofilm-mediated disease. This study aimed to evaluate associations between severe-ECC (S-ECC), the oral microbiome, and variants in genes that encode components of the G protein-coupled receptor (GPCR) signaling cascade involved in taste sensation. A total of 176 children (88 caries-free; 88 with S-ECC) were recruited. Analyses of 16S and ITS1 rRNA microbial genes and seven (GNAQ, GNAS, GNAT3, GNAI2, RAC1, RALB, and PLCB2) human genes were pursued using next-generation sequencing. Regression analyses were performed to evaluate associations between genetic variants, S-ECC, and the supragingival plaque microbiome. Results suggest that PLCB2 rs2305645 (T), rs1869901 (G), and rs2305649 (G) alleles had a protective effect on S-ECC (rs2305645, odds ratio (OR) = 0.27 (95% confidence interval (CI): 0.14–0.51); rs1869901, OR = 0.34 (95% CI: 0.20–0.58); and rs2305649, OR = 0.43 (95% CI: 0.26–0.71)). Variants in GNAQ, GNAS, GNAT3, PLCB2, RALB, and RAC1 were associated with oral fungal and bacterial community composition. This study revealed that three loci at PLCB2 are significantly associated with S-ECC. Variants in multiple genes were associated with the composition of dental biofilm. These findings contribute to the current knowledge about the role of genetics in S-ECC.     

经亚氯酸钠和白腐菌处理后蔗渣半纤维素的分离

蔗渣经亚氯酸钠脱木素后,木素含量降到了3.4%,木素脱除率达到85.0%,抽提出的半纤维素纯度达到84.8%;将亚氯酸钠和白腐菌处理结合起来,能将蔗渣木素脱除92.1%,抽提的半纤维素纯度达到87.4%,聚戊糖抽提率也有较大提高。     

The Antifungal Compound Totarol of <Emphasis Type="Italic">Thujopsis dolabrata</Emphasis> var. <Emphasis Type="Italic">hondai</Emphasis> Seeds Selects for Fungi on Seedling Root Surfaces

Hinoki-asunaro (Thujopsis dolabrata Sieb. et Zucc. var. hondai Makino) is a tree endemic in Japan whose seeds produce several terpenoids. We hypothesized that antifungal compounds in seeds might select for fungi on the root surfaces of T. dolabrata var. hondai seedlings. We examined seed and soil fungi, their sensitivity to methanol extracts of the seeds, the fungi on root surfaces of seedlings grown in Kanuma pumice (a model mineral soil) and nursery soil, and the frequency at which each fungus was detected on the seedling root surface. We calculated correlation coefficients between fungal detection frequency on root surfaces and fungal sensitivity to seed extracts. We also isolated from the seeds the antifungal compound totarol that selected for fungi on root surfaces. Species of Alternaria, Cladosporium, Pestalotiopsis, and Phomopsis were the most frequently isolated fungi from seeds. Mortierella and Mucor were the dominant fungi isolated from Kanuma pumice, whereas Umbelopsis and Trichoderma were the main fungi isolated from nursery soil. Alternaria, Cladosporium, Mortierella, Pestalotiopsis, and Phomopsis were the dominant fungi isolated from root surfaces of seedlings grown in Kanuma pumice, and Alternaria, Cladosporium, Pestalotiopsis, Phomopsis, and Trichoderma were the main root-surface fungi isolated from seedlings grown in nursery soil. The fungal detection frequencies on root surfaces in both soils were significantly and negatively correlated with fungal sensitivity to the seed extract. A similar correlation was found between the fungal detection frequency on root surfaces and fungal sensitivity to totarol. We conclude that totarol is one factor that selects for fungi on root surfaces of T. dolabrata var. hondai in the early growth stage.     

Fungi Level Analysis of Cocoa Beans Based on Fermentation Box Type and Duration

In certain location, it is undeniable that there are qualities variations of fermented cocoa beans depend on processing techniques. In addition, its cocoa bean's production central at Yogyakarta have their specific characteristic own regarding the use of fermentation box (box type). The purpose of this research was to analyze the effects of three types of fermentation box and duration to fungi level of fermented cocoa beans. CRD (completely randomized design) with two factors and three replications is applied as assessment method. The first factor is the type of fermentation box (basket, storey box and single box with a hand crank) and the second factor is the length of fermentation time (3 and 5 days). The result of the research explained that the lowest levels of the fungi achieve within 5 days of fermentation processes. Meanwhile, a single box with a hand crank provide the lowest of fungi's level. Furthermore, the combination of those two results may give the most favorably expected condition of fungi level.     

EDX measurements and SEM examination of surface of some imported woods inoculated by three mold fungi

Wood samples of Pinus rigida, Juglans nigra, and Fagus sylvatica were superficially inoculated with three mold fungi (Penicillium selerotigenum, Paecilomyces variotii, and Aspergillus niger). The changes in wood surfaces and the elemental composition were observed by scan electron microscope (SEM) and the electron dispersive X-ray spectroscopy (EDX), respectively. Wood elemental composition was an indication of the growth of mold fungi, in which P. selerotigenum, and A. niger have consumed high amount of carbon (C) of F. sylvatica wood compared to control treatment. Also, P. selerotigenum consumed high amount of C of J. nigra wood compared to the control. While, the three mold fungi showed little changes in C content in P. rigida wood. The nitrogen element in the studied woods was completely consumed by the three mold fungi. Cl element increased in the three woods as inoculated by the three fungi compared to untreated woods. Other elements such as S, Si, Ca, Zn, Cu, and Fe varied in their content in accordance to the interaction among wood species and fungi. The growth of the three mold fungi showed distribution and structures of spores and hyphae covering deteriorated wood surfaces. The study suggests that the three mold fungi metabolize the carbon-rich constituents of the investigated wood species in a proportional manner and produce large fruiting structures that release vast numbers of spores in nature.     

Control of Foodborne Pathogenic and Spoilage Bacteria by Garcinol and Garcinia indicaextracts, and their Antioxidant Activity

ABSTRACT: Spent rinds of Garcinia indica were extracted with hexane and benzene using a Soxhlet extractor for 4 h. The major compound present in both extracts was found to be garcinol, as confirmed by fractionation and spectroscopic studies. The minimum inhibitory concentrations of hexane extract, benzene extract, and garcinol against a few Gram-positive and Gram-negative bacteria were in the range of 15 to 1000, 20 to 1250, and 1.5 to 500 ppm, respectively. The antioxidant activity of these fractions at 25 ppm was 63.2%, 61.7%, and 92.4%, respectively, as evaluated by the 1,1-diphenyl-2-picrylhydrazyl method. Hexane extract, benzene extract, and garcinol showed 1027, 985.5, and 1195.9 μmol/g of ascorbic acid equivalents, respectively, at 100 ppm concentration using the phosphomolybdenum method. These findings may be useful for possible application of the previously described fractions as biopreservatives.     

Biopreservation potential of lactic acid bacteria from Andean fermented food of vegetal origin

Microbial fermentations have long represented a way of natural biopreservation of raw materials, which frequently originated new food products. Among them, traditionally fermented products still manufactured by native populations all around the world are source of lactic acid bacteria (LAB) strains with high biotechnological potential. LAB are food grade microorganisms and therefore a good alternative to chemicals to be applied in food preservation. A total of 130 LAB isolates recovered from “chicha” and “tocosh”, traditional fermented Andean products of vegetal origin, were screened for antimicrobial activities against spoiler fungi Meyerozyma guilliermondii CECT 1021 (synonym Pichia guilliermondii), Penicillium roqueforti CECT 2905^NT, Aspergillus oryzae CECT 2094^NT and Aspergillus niger CECT 2807 as well as against foodborne pathogens Escherichia coli O157:H7 CECT 5947, Listeria innocua CECT 910^T and Salmonella enterica subsp. enterica serovar Typhi CECT 4138. LAB isolates represented nine species and four genera that exhibited a general inhibition of food pathogens and were also active against A. oryzae and M. guilliermondii while a poor inhibition of A. niger and P. roqueforti was produced. Antifungal activity of cell free supernatants (CFS) from seven selected strains grown in MRS was confirmed against toxigenic fungi Aspergillus parasiticus CECT 2681, Penicillium expansum CECT 2278 and Fusarium verticilloides CECT 2987 and also on the three foodborne bacteria included in the study. Phenyllactic and 3,5-Di-O-caffeoylquinic acids were identified as the predominant bioactive compounds in CFS by QuEChERS extraction with LC-MS-LIT detection approach. Four out of seven strains free of antibiotic resistances involving L. plantarum M5MA1 and M9MM1 from chicha and L. fermentum T3M3 and Lc. mesenteroides T1M3 from tocosh showed high potential to be used as biopreservatives in food applications.     

Authentic heterologous expression of the tenellin iterative polyketide synthase nonribosomal peptide synthetase requires coexpression with an enoyl reductase

The tenS gene encoding tenellin synthetase (TENS), a 4239-residue polyketide synthase nonribosomal-peptide synthetase (PKS-NRPS) from Beauveria bassiana, was expressed in Aspergillus oryzae M-2-3. This led to the production of three new compounds, identified as acyl tetramic acids, and numerous minor metabolites. Consideration of the structures of these compounds indicates that the putative C-terminal thiolester reductase (R) domain does not act as a reductase, but appears to act as a Dieckmann cyclase (DKC). Expression of tenS in the absence of a trans-acting ER component encoded by orf3 led to errors in assembly of the polyketide component, giving clues to the mode of programming of highly reducing fungal PKS. Coexpression of tenS with orf3 from the linked gene cluster led to the production of a correctly elaborated polyketide. The NRPS adenylation domain possibly shows the first identified fungal signature sequences for tyrosine selectivity.