FIRST RECORD OF CANTHARELLUS MINOR IN VIETNAM

This species of mushroom with orange fruiting bodies and yellow flesh grows in clumps on the forest land in the coordinates 11o56'34.45" N, 108o28'33.56" E in the pine (Pinus kesiya) forest, Da Lat City, Lam Dong Province, Vietnam. The results of analysis on the morphology, both macro- and micro-morphological characteristics of this mushroom showed that, pileus: 5-15 mm wide, infundibuliform; yellowish to orange; margin incurred, wavy-liked margin, non-striate; Pileus surface: smooth, scaleless, yellowish; Lamellae: distant, decurrent, not intervenose, concolorous to pileus; Context: concolourous to the pileus, slight sweetness, aromatic flavor; Stipe: cylindrical shape, surface smooth, concolourous to pileus, 1-2 mm diameter, 20-50 mm length; Basidiospores: 6-11.5 x 4-6.5 μm, ovoid-ellipsoid with smooth surface; Basidia: 65 x 10 μm, cornuted 4-6 spores per basidium. Phylogenetic analysis of nrLSU sequence yielded consistent topology in different taxa of Cantharellus. The phylogenetic position of XC02 was obtained and accepted at sub-generic level: subgenus Parvocantharellus. This clade was suggested to be monophyletic, and separated from other sub-generic levels. Morphologically phylogenetically distinct from the other species of clade 4, such as C. appalachiensis, C. tabernensis, C. aff. Congolensis. The highly supported monophyletic group with referent Cantharellus minor was obtained with the bootstrap value of 99, indicated that XC02 was significant closely to Cantharellus minor. Phylogenetic of nrLSU analysis revealed clades with statistical support corresponding to morphological observation, thus, XC2 was concluded as Cantharellus minor

Willingness to Pay for Improving Household Solid Waste Management in Vietnam

Management of solid waste is a major challenge in urban areas of most parts of the world, especially in developing countries. The study aimed to determine and estimate the willingness to pay (WTP) of the selected households for the improvement of solid waste management in Vietnam. The research evaluated WTP of household solid waste in case studies in Bien Hoa and My Tho cities using contingent valuation method (CVM). The data were collected through a closed-ended questionnaire survey and interviews with 200 households. The results showed that the most willingness to pay was equal to 10,000 and 15,000 VND per month. The respondents were willing to pay in Bien Hoa and My Tho with an average of 14,450 VND (0.63 USD) and 13,000 VND (0.56 USD) per month, respectively. Regression model identified influential factors on WTP of households in the two cities of Vietnam. The factors that significantly influence households’ WTP were monthly household income, education of respondents, age, occupation and solid waste volume (p<0.05). The results of this study can be used for the urban planning and implemented the sustainable development process in Bien Hoa and My Tho cities

On the Inhibitability of Natural Products Isolated from Tetradium ruticarpum towards Tyrosine Phosphatase 1B (PTP1B) and α-Glucosidase (3W37): An In Vitro and In Silico Study

Folk experiences suggest natural products in Tetradium ruticarpum can be effective inhibitors towards diabetes-related enzymes. The compounds were experimentally isolated, structurally elucidated, and tested in vitro for their inhibition effects on tyrosine phosphatase 1B (PTP1B) and α-glucosidase (3W37). Density functional theory and molecular docking techniques were utilized as computational methods to predict the stability of the ligands and simulate interaction between the studied inhibitory agents and the targeted proteins. Structural elucidation identifies two natural products: 2-heptyl-1-methylquinolin-4-one (1) and 3-[4-(4-methylhydroxy-2-butenyloxy)-phenyl]-2-propenol (2). In vitro study shows that the compounds (1 and 2) possess high potentiality for the inhibition of PTP1B (IC50 values of 24.3 ± 0.8, and 47.7 ± 1.1 μM) and α-glucosidase (IC50 values of 92.1 ± 0.8, and 167.4 ± 0.4 μM). DS values and the number of interactions obtained from docking simulation highly correlate with the experimental results yielded. Furthermore, in-depth analyses of the structure–activity relationship suggest significant contributions of amino acids Arg254 and Arg676 to the conformational distortion of PTP1B and 3W37 structures overall, thus leading to the deterioration of their enzymatic activity observed in assay-based experiments. This study encourages further investigations either to develop appropriate alternatives for diabetes treatment or to verify the role of amino acids Arg254 and Arg676

Investigating Visible-Photocatalytic Activity of MoS2/TiO2 Heterostructure Thin Films at Various MoS2 Deposition Times

MoS2/TiO2 heterostructure thin films were fabricated by sol-gel and chemical bath deposition methods. Crystal structure, surface morphology, chemical states of all elements, and optical property of the obtained thin films were characterized by using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis spectroscopy techniques, respectively. Photocatalytic activity of all thin films was evaluated by measuring decomposition rate of methylene blue solution under visible light irradiation. The results indicate that ultrathin MoS2 film on TiO2-glass substrate improves photocatalytic activity of TiO2 in the visible light due to the efficient absorption of visible photon of MoS2 few layers and the transfer of electrons from MoS2 to TiO2. All MoS2/TiO2 heterostructure thin films exhibit higher visible light photocatalytic activity than that of pure MoS2 and TiO2 counterparts. The best MoS2/TiO2 heterostructure thin film at MoS2 layer deposition time of 45 minutes can decompose about 60% MB solution after 150 minutes under visible light irradiation. The mechanism of the enhancement for visible-photocatalytic activity of MoS2/TiO2 heterostructure thin film was also discussed