Vietnam Academy of Science and Technology: Journals Online
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High-mannose type N-glycan binding specificity of a novel lectin from the red alga (Betaphycus gelatinus)
No full textThe red alga, Betaphycus gelatinus is one of carrageenan sources in the world. The lectin from the red alga B. gelatinus was isolated by a combination of aqueous ethanol extraction, ethanol precipitation, ion-exchange chromatography and gel filtration chromatography and was designated as BGL after the specific name of alga. Lectin gave a single band with molecular mass of about 19,000 Da in both non-reducing and reducing SDS-PAGE conditions, therefore lectin exists in monomer form. The hemagglutination activities of BGL were stable over a wide range of pH from 3 to 10, temperature up 60 oC and not affected by either the presence of EDTA or addition of divalent cations, indicating that lectin requires no metal for biological activity. The hemagglutination activities of BGL were not inhibited by monosaccharides and glycoproteins, D-glucose, D-mannose, D-galactose, D-xylose, N-acetyl-galactosamine, N-acetyl-glucosamine, N-acetyl-neuraminic acid, N-acety-D-mannosamine, transferrin and fetuin, but strongly inhibited by glycoproteins bearing high-mannose type N-glycan, such as yeast mannan and porcine thyroglobulin. Lectin BGL is specific for N-glycans and may recognize terminal (α1–3) or (α1–6)-linked mannose residues in structure Man(α1-6)[Man(α1-3)]Man(α1-6)[Man(α1-3)]Man(β1-4)GlcNAc(β1-4)GlcNAc of N-glycans. High-mannose type N-glycan binding specificities of this lectin highly resemble with those of the anti-cancer, anti-virus and anti-bacteria lectins from the red algae, carrageenophytes, including Eucheuma serra (ESA-2), Eucheuma denticulatum (EDA-2), Kappaphycus striatum (KSA-2), Kappaphycus alvarezii (KAA-1 and KAA-2) and Solieria filiformis (SfL1 and SfL2). The red alga B. gelatinus could promise to be a good source of valuable lectins for application in biochemistry and biomedicine
The anticancer activities of stichoposide D isolated from the sea cucumber Stichopus chloronotus on NTERA-2 cancer stem cells
No full textAs reported, cancer stem cells (CSCs) are in charge of dangerous characteristics including drug resistance, metastasis, recurrence and therapeutic effectiveness. Therefore, CSCs are an important target for discovering of novel effective and specific anticancer drugs. In Vietnam, the Stichopus chloronotus sea cucumber is found as a potential biological source with various active ingredients. Particularly, the active triterpene saponin stichoposide D, which was isolated from S. chloronotus, showed strong cytotoxic activity in leukemias. Herein, stichoposide D was further studied its potential anti-CSCs activities on pluripotent human embryonic carcinomas NTERA-2 cells. The compound exhibited its promising and specific cytotoxic activities in NTERA-2 cells with the IC50 = 0.26 ± 0.02 µM, in comparison with that ranging from 0.35 ± 0.02 µM to 0.53 ± 0.03 µM (P0.05), tested on non-CSCs cancer cell lines, which were breast carcinoma (MCF-7) and lung adenocarcinoma (SK-LU-1), respectively. The working fashion of the compound on NTERA-2 cells could be apoptotic induction. Significantly, treatment of stichoposide D at 1 µM induced 76.4% of apoptotic cells as well as 1.72 relatively fold change of caspase-3 activation in comparision with the control (P0.05). Meanwhile, stichoposide D was the first time recorgnized its positive efficacy on reducing the number of highly expressed CD44+/CD24+ cells, which were reported as typically CSCs characterized population. The compound also exhibited some effects on NTERA-2 cell cycle of which it arrested cells at sub-G1 phase (15.03%) and prevented those CSCs to enter the S-phase for DNA synthesis. In conclusion, stichoposide D presents potential anti-CSCs activities and should be further studied for future applications
STUDY ON ADVANCED TREATMENT OF WASTEWATER BY ULTRA FILTRATION FOR REUSING PURPOSE – ON-SITE PILOTS
No full textReclaimed water has been greatly applied worldwide recently to augment water supply for non-potable domestic purpose. The present study put an effect on assessing the application of ultra-filtration (UF) on advanced treatment following conventional domestic wastewater treatment and coal mining wastewater for reusing purpose. On-site advanced treatment pilots using UF membrane with the capacity of 1 – 1.5 m3/h were built to treat decentralized domestic wastewater which has a low concentration of organic matters and coal mining wastewater which is abated by chemical-physical process and advanced treatment train. Dissolved oxygen (DO), pH, Chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS), volatile suspended solids (VSS), Total Nitrogen (TN) and ammonium-nitrogen (NH4-N) in domestic wastewater and TSS, iron (Fe), manganese (Mn), and hardness of coal mining wastewater were analyzed. The pollutants in domestic wastewater were reduced significantly as of 82% TSS, 86% BOD5, 82% COD, and 96% NH4-N. The removal efficiency in coal mining wastewater reached 93.5% TSS, 67% iron, 68% manganese, and 52% hardness. The analyzed parameters in permeate of both pilots met legislation thresholds of Vietnam technical regulation on domestic water quality, proving that reclaimed water treated by UF can be used for non-potable domestic purposes
HIGH PHOTOCATALYTIC ACTIVITY OF MAGNETIC COMPOSITE PHOTOCATALYST NiFe2O4/BiVO4 FOR RHODAMINE B DEGRADATION UNDER VISIBLE LED LIGHT IRRADIATION
No full textTo improve the photocatalytic activity of BiVO4 semiconductor, the design of composite photocatalyst containing BiVO4 with surpassing the recombination of photoinduced electron and hole is highly required. In this study, magnetic composite photocatalyst with NiFe2O4 and BiVO4 has developed through two-steps hydrothermal method. The results show that the morphology of the bare BiVO4 had a decahedral shape with smooth surfaces along with particles, while the morphology of the bare NiFeO4 had nanoparticles with the diameter in a range of 10-20 nm. In the case of 20% NiFe2O4/ BiVO4 samples, a large of nanoparticles were deposited into large bulk, implying the incorporation of NiFe2O4 nanoparticles on the surface of BiVO4 catalyst. Compared with the bare BiVO4, the NiFe2O4/BiVO4 composites had a higher photocatalytic efficiency for photodecomposition of rhodamine B (RhB) under visible LED light irradiation. The improvement of photocatalytic degradation RhB activity should be attributed to a direct Z‐scheme system. Therefore, the fabrication of semiconductors with a combination of magnetic materials provides new insight for the enhancement of their photocatalytic performance
SYNTHESIS OF ZEOLITE-ACTIVATED CARBON COMPOSITE FOR REMOVAL OF AMMONIUM FROM AQUEOUS SOLUTION
No full textIn this study, zeolite-activated carbon composite (Z/AC) was synthesized by hydrothermal reaction using kaolin as a source of silica and alumina. The synthesized materials were characterized by Brunner-Emmet-Teller (BET) surface area to calculate surface area, X-ray diffraction (XRD) to study the crystal structure of materials, Infrared spectroscopy (IR) to indicate the presence of functional groups on the surface and scanning electron microscopy (SEM) to determine the morphology of the composites. In this paper, adsorption equilibrium and kinetics for the removal of ammonium by prepared Z/AC materials were evaluated
Database construction for Vietnamese catfish genome
No full textMolecular biological research plays an important role in aquaculture, contributes to the improvement ofbroodstocks efficiently. Recently, with the development of next-generation sequencing (NGS) technology,genomic studies have been rapidly increased, in which data organisation and management hold a crucialposition. After obtaining NGS sequencing data of Vietnamese catfish (Pangasianodon hypophthalmus), wehave analysed and annotated the catfish genome, from which we have constructed a database for efficientusage. The database is built upon open source software following a three-layer model (interface, Web serviceand database) with a convenient interface through Web browsers. Users can look up sequence and annotationdata as well as visualize sequences through the Jbrowse genome browser. This database is important resourcefor functional genome and genetic improvement of the catfish
The functional response and predatory ability of the reduviid Coranus fuscipennis Reuter (Heteroptera: Reduviidae)) fed on the rice meal moth Corcyra cephalonica (Stainton)
No full textThe reduviid Coranus fuscipennis Reuter (Heteroptera: Reduviidae) is an important predator for biological control the pests of vegetables in Vietnam. The functional response of the 2nd, 3rd, 4th, 5th nymphal instars and adult male and female of the predator C. fuscipennis to the larvae of rice meal moth Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) was evaluated in laboratory conditions (temperature 30±2ºC; relative humidity 75±5%; and 14:10 h Light:Dark). The results show that the nymph and adult of C. fuscipennis responded to different densities of prey. They killed more number of prey at higher prey densities and less prey at lower prey densities that produced a curve linear type II functional response (Holling 1959). The maximum consumption was always found restricted when rearing the C. fuscipennis at high prey densities. The relationship between the predation rate of the C. fuscipennis and the prey densities was negative correlation (R is between 0.70 and 0.98), but between the number prey killed and the prey density is positive correlation. The searching time prey of the C. fuscipennis decreased when the prey densities increased that was confirmed by the negative correlation (R between 0.85 and 0.98). The reduviid C. fuscipennis bred by the C. cephalonica in laboratory and they can use for biological control some pests of vegetables (P rapae, S. litura and P. xylostella) in Vietnam
Evaluating the effects of simulated microgravity on mouse fibroblast
No full textThe present study investigated how mouse fibroblasts changed under microgravity (SMG) conditions ( 10-3 G) simulated by 3D clinostat. Results showed that SMG condition markedly reduced the proliferation of mouse fibroblasts, significantly reducing the nuclear area and intensity. Compared to the control group, the mouse fibroblasts ratio of the SMG group was higher in the G0/G1 phase but lower in the S phase and G2/M phase. The ratios of early and late apoptotic cells were also higher in the SMG group. The mouse fibroblasts under SMG conditions exhibited a reduction of β-Actin and α-Tubulin 3 expressions compared to the control group. These results suggested that the SMG condition diminished the proliferation and downregulated cytoskeletal protein expression of mouse fibroblasts.
Using Arachis pintoi leaf extracts in biosynthesis of silver nanoparticles for improving the vase life of cut carnation (Dianthus caryophyllus L.)
No full textA biological method for synthesizing silver nanoparticles (SNPs) using the leaf extracts of Arachis pintoi Krapov. W.C. Greg. was developed. The optimum conditions of input materials were found with leaf autoclaving in 15 min, 20 g fresh leave, and 4 mM of silver nitrate (AgNO3). To study the role of time, temperature, and solution pH of the reaction, varying time reaction (5, 30, 60, 90, 120, 150, and 180 min), temperature reaction (10, 20, 30, 40, and 50oC) and pH of the solution (1, 3, 5, 7, 9, and 11) were investigated. The optimal biosynthesis conditions were achieved in 180 min of reaction time at 50oC and pH 11. The obtained nanoparticles have spherical and oblong in shape with average size of 26.4 nm. The SNPs in 4 concentrationss (5, 15, 25, and 35 ppm) combined with and without 2% sucrose extended vase life, enlarged flower diameter, and maintained increase the relative fresh weight with vase solution uptake rate. SNPs inhibited significantly the bacterial growth in the stem end and vase solution, reduced the blockage in stems and therefore promoted the postharvest quality of carnation cut flowers. Out of the treatments, administration of 5 ppm SNPs with 2% sucrose of vase solution gave the best results for all parameters. The biosynthesis SNPs could be applied as a promising preservative solution for carnation cut flowers
DETERMINATION OF CYCLAMATE CONTENT IN SOME FOOD PRODUCTS USING UPLC-MS/MS
No full textAdditives used in food pose a risk to consumers' health, and cyclamate is one of the chemical sugars. In this study, cyclamate content in 38 food samples including beverage, cake, candy, milk, and juice was analyzed using Ultra-Performance Liquid Chromatography, Tandem Mass Spectrometry (UPLC-MS/MS). The optimal parameters of detector MS/MS for anion mode; the liquid chromatography column UPHR(R) BEH C18 2.1x100mm 1.7μm, waters, USA; mobile phase: MeOH:H2O (50:50) including 1% HCOOH, deionized water. The ultimate test sample which passed 0.2 μm membrane filter results in retention time: 4.05 minutes, and flow rate of 0.2 mL/min. The quantitative and confirmable ions are 79.7 and 177.9 m/z, respectively. Under the optimum conditions the calibration curve for cyclamate was linear in the range of 5-100 mg/L m with R2= 0.9955, LOD 2.92 mg/kg; LOQ 9.72 mg/kg, bias found 0.015 %, RSD 0.22; recovery ranged 83.38 to 93.40%. The results showed that 23/38 food product samples from markets and supermarkets in Hanoi city contained cyclamate, accounting for 62.53%, with concentrations ranging from 10.9 to 178.1 mg/kg. However, the content of cyclamate in all samples have met the standards as regulated in Circular No. 08/2015/TT-BYT. In addition, cake and candy samples used cyclamate more frequently compare to other analyzed food types