Science & Technology Development Journal: Natural Sciences

Latest Articles

1. Original Research

   Petrographical, petrogeochemical characteristics, and petrogenesis of the granitoid in the Que Tho area, Quang Nam province

   Phẳng T.,ần Hoàng N.,ễn Trí N.ễn

   Que Tho area is the southwest part of Que Son block in Que Tho commune, Hiep Duc district, Quang Nam province. The granitoid in this area had a relatively isometric block form. The main petrographic composition of this granitoid consists of biotite granodiorite and hornblende biotite granodiorite (phase 2), with diorite (phase 1) present as xenoliths in granodiorite. Its mineral composition mainly was quartz (20−30%), plagioclase (30−40%) and potassium feldspar (25−30%); Colored minerals consisted of biotite (5−10%), amphibole (~5%) and pyroxene (3−5%); typical minor minerals were sphene, apatite, zircon (few). Common post-magmatic metasomatic processes include albitization, microlinization, chloritization, sericitization, and zoisite−epidotization. The average characteristic chemical composition of this granodiorite (%) was SiO2 64.56, TiO2 0.75, Al2O3 15.85, FeO 4.0, Fe2O3 0.45, MnO 0.06, MgO 2.32, CaO 3.95, K2O 3.38, Na2O 3.89, P2O5 0.28; ratio of alkaline K2O/Na2O: 0.86 (<1), The ASI with corundum index was 0.93 (< 1), ratio Rb/Sr 0.19; Ba/Sr 6.63; Ba/Rb 8.4; Th/U 3.99; Zr/Hf 45.87 and Nb/Ta 16.25 and the negative anomaly value Eu was from moderate to strong. The granodiorite belongs to the high aluminum series, calc-alkali series, alkaline type K−Na, high K; I-granite type originated from mantle, formed in the tectonic setting of an intrusive−volcanic arc of an active continental margin and crystallized differently from the mafic magma and influenced by the composition of the crust. The crystallization age of the granodiorite, determined by the LA-ICP-MS U-Pb zircon method, was 279.1± 2.7 million years, corresponding to the Early Permian stage. Compared to the granitoid formations in South Vietnam, the granitoids in the Que Tho area belonged to phase 2 of the Ben Giang−Que Son complex, commonly found in the Kon Tum terrane.

   Published: 2024-10-04In press
2. Original Research

   Improving thermal properties and flame characteristics of aerogel from nanocellulose and graphene oxide by sodium bicarbonate

   Vy N., Duy K.,ổn., Hân Dươn., Phương Lý

   In this study, an environmentally friendly aerogel derived from nanocellulose fibers (CNF) combined with graphene oxide (GO), polyvinyl alcohol (PVA), and sodium bicarbonate (NaHCO3) was synthesized with the aim of improving the thermal properties and flame characteristics of aerogels made from nanocellulose and graphene oxide. Aerogel obtained by freeze-drying technique has a low density (0.2236 g/cm3), a high porosity of 85.92%, a specific surface area when adsorbing and desorbing nitrogen gas is approximately 44.6 m2/g and 67.05 m2/g, respectively. Additionally, the resulting aerogel was structurally analyzed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The research shows that the presence of NaHCO3, a green and low-cost flame retardant additive, has significantly improved the thermal stability and flammability of the nanocellulose-based aerogels. In addition, the presence of this flame retardant additive has almost no effect on the MB adsorption and removal ability of the resulting aerogel, with the removal efficiency remaining stable at over 95% after 5 reuse cycles. The results show that the CNF/GO/PVA/NaHCO3 aerogel is a lightweight material with low density and a large surface area, making it favorable for adsorption applications in environmental treatment. Additionally, the CNF/GO/PVA/NaHCO3 aerogel has significantly improved in thermal stability, which opens up new possibilities for the thermal recycling of this adsorbent.

   Published: 2024-10-04In press
3. Original Research

   A screening study on the urease inhibitory activity of plants collected in Central Highland and Southern Vietnam

   Le T., Nguyen H., X., Le K., M., Truong N., T., Do T., N., V., Nguyen N., T., Nguyen M. T. T.

   In research on treating gastric ulcers induced by H. pylori bacteria, urease inhibition has proven to be a practical therapeutic approach. In this investigation, 44 medicinal plant species collected from Central Highlands and Southern Vietnam were meticulously selected through three distinct methods to screen their anti-urease activities. At a concentration of 250 µg/mL, fifteen plants exhibited more than 50% inhibition of the enzyme. Subsequently, further assessment of the urease inhibition capability was conducted at many different concentrations, revealing that rhizomes of C. aromatica, stems of C. quadrangulare and S. roxburghii, seeds of C. bonducella, and green tea leaves (C. sinensis) demonstrated the ability to potently inhibit urease with IC50 values of 22.5, 58.5, 80.8, 86.6, and 97.7 µg/mL, respectively, compared to the positive control, hydroxyurea (IC50 = 6.5 µg/mL). Among them, C. aromatica rhizomes exhibited the highest level of inhibition, suggesting a promising prospect for development into a pharmaceutical agent to support the treatment of H. pylori-induced stomach ulcers. The primary objective of this study is to contribute essential data on Vietnamese medicinal plants capable of treating gastric ulcer-related ailments by targeting H. pylori inhibition.

   Published: 2024-10-04In press
4. Review

   Recombinant antibodies and their applications in biomedicine

   Nguyen-Huynh P.,-T., Mai-Hoang T.,-D., Tran-Van H.

   Recombinant antibodies are increasingly showing potential in the treatment of severe human diseases. This paper aims to provide a general information about recombinant antibodies and some of their applications in biomedicine, especially in the cancer treatment. Recombinant antibodies maintain the antigen-specific binding ability in the same way as monoclonal and polyclonal antibodies, with several additional advantages. The first generation of recombinant antibodies “Fab antibodies” and more formats such as scFv showed high mobility and small structure, with tissue invasion and tumor targeting applications in the cancer immunotherapy and diagnostic imaging. Nanobody represented the smallest type of recombinant antibodies. With excellent tissue distribution, and the blood-brain barrier (BBB) crossing ability, nanobody became an effective tool in the treatment of cancer and neuroinflammatory diseases. Fcab was a recombinant antibody originating from the Fc fragment with antigen-specific binding and immune response stimulating ability and was highly stable in the body. In recent years, most recombinant antibodies have been studied for the application in the delivery and release of cytotoxic drugs by the antibody-drug complex (ADC). With the strong development of gene engineering and immunotherapies, recombinant antibodies are now a potential therapy in the treatment of deadly diseases in humans.

   Published: 2024-10-04In press
5. Original Research

   Survey of the Polyvinylidene Fluoride (PVDF) ratio and evaluation of electrochemical properties of Gel-Polymer PEO/PVDF/SiO2/LiTFSI membranes used for Li||LiFePO4 batteries

   Nguyen T., Phat V., Tran M., Le P.

   This paper presented the preparattion of a gel polymer electrolyte (GPE) based on poly(ethylene oxide) (PEO) as the host polymer, by blending with the additives polyvinylidene fluoride, PVDF, and a combination of nano silica (SiO2) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. The GPE membranes were prepared by dissolving the compounds in N,N-dimethylformamide (DMF) solvent and drying at 60 oC. The results showed that the addition of PVDF improved the thermal stability and enhanced the mechanical properties of the GPE membrane structure. Futhermore, the incorporation of SiO2 promoted the dissociation of the Li+ ion from the LiTFSI salt. The electrochemical properties of the GPE membranes were investigated within the range of PVDF mass concentrations at 0%, 5%, 10%, 15% and 20%, with a fixed 5 wt% SiO2 and 15 wt% LiTFSI relative to the total PEO mass. The Linear Sweep Voltammetry (LSV) measure showed that the sample with the composition of PEO – 5 wt% PVDF – 5 wt% SiO2 – 15 wt% LiTFSI being the best oxidation onset potential (3.9 V vs. Li+/Li). The Electrochemical Impedance Spectroscopy (EIS) results showed that the Li+ ion conductivity of this GPE membranes reached 2.32 × 10-4 S/cm at 60 oC, and the discharge capacity was 104 mAh/g at C/10 rate. The obtained results showed that the GPEs would be for applications in Li−ion batteries.

   Published: 2024-10-04In press
6. Original Research

   An artificial neural network model was developed to predict the density of polymer materials used in gamma scattering and gamma transmission measurements

   Trương S., Nguyễn K., Huỳnh C.,ươn., Lê T., Nguyễn L., Nguyễn Đạt Hoang T.

   This paper presents a new approach using an artificial neural network (ANN) allows for the density of polymer materials based on input data obtained from gamma transmission and gamma scattering measurements. Besides the results of sample density, this approach also allows for the detection of any defects inside the sample. The conventional method for measuring material density involves determining the mass and volume of a sample, and the density measured in this way is the average density of the sample. This means that it is not possible to detect defects within the sample based on average density without destroying it. Unlike the conventional approach, this proposed method allows for the measurement of the detection of a material at a specified location of the sample, known as the local density. This allows for the detection of defects inside the sample without destroying it. To achieve this, the data used to train the ANN model, were generated using a Monte Carlo simulation. The parameters of the ANN model were investigated to find the optimal configuration for predicting the density of polymer materials. The experimental data was fed into the optimal ANN model to predict the density of 8 types of polymers, including polyoxymethylene (POM), Teflon (PTFE), polyvinylidene fluoride (PVDF), polyether ether ketone (PEEK), polybutylene terephthalate (PBT), acrylonitrile butadiene styrene (ABS), polyamide (PA) and polyurethane (PU). The results showed that the relative deviation between the reference density and the predicted value was less than 4%. Based on these results, the proposed method is reliable and highly feasible when applied to measuring the density for actual measurements, providing an additional solution besides previously available methods.

   Published: 2024-09-30In press
7. Original Research

   Analysis of the morphological characteristics, microstructural anatomy, and powdered herb Curcuma aromatica Salisb.

   Huỳnh N.,àn Lê T.,ấn Cao G., Lê Út Nguyễn N.,ệt Vũ T.,ảo Trịnh A., Nguyễn Hươn.

   Wild turmeric (Curcuma aromatica Salisb.) is a valuable medicinal species, commonly used in traditional medicine to treat infections, cancers, and wound healing. The correct identification of medicinal plants is most important in the context of developing raw material areas for pharmaceutical production. In this study, the characteristic morphological features of White turmeric were described. The results noted that the plant has pseudostems that can grow up to 1 meter tall. Young leaves exhibit a light burgundy area at the main vein. The cross-section of the rhizome and tuberous root had a yellow color and distinctive aroma. Inflorescences grow from the rhizome before leaves appear. Infertile bracts are pink. Fertile bracts are light green. Large labelums are white with yellow-orange midribs. One fertile stamen, anther connective generally elongated into a short crest; the base of the anthers extends into sharp awl-shaped spurs. The ovary is spherical with hairs, and the stigma has a funnel-shaped, flared knob. In addition, the anatomical characteristics of each plant’s organ and the microstructure of the herbal powder were also analyzed, with remarkable: tetracellular stomata, yellow secretory cells, dark yellow plastic mass, and cubic crystals. The results of the study contribute to completing the database to serve the needs of accurate identification and testing of medicinal herbs in wild turmeric species, a premise for the selection, breeding, conservation, and development of medicinal areas in Vietnam.

   Published: 2024-09-30In press
8. Original Research

   Five flavonoids from the stems of Mangifera reba and their -glucosidase inhibitory activity

   Duong T., T., Le T., Do N., T., Nguyen H., Tran T., Dang P., Nguyen N., Nguyen Thi-Thanh M.

   Mangifera reba (Mangifera), belonging to the Anacardiaceae family, grows mainly in tropical and subtropical countries such as India, Vietnam, Malaysia and Thailand. Its chemical constituents are triterpenoids, flavonoids, xanthones, benzophenones and polyphenols. Previous studies presented that Mangifera reba contained abundant biological activities such as antibacterial, antioxidant and cytotoxic activity against breast cancer cell line MCF-7. However, research and databases in Vietnam are little available for this species. This paper presented the chemical constituents from the stems of Mangifera reba to provide more information to the database on medical plants in Vietnam. By using silica gel column chromatography and preparative TLC, eluting with organic solvents of different polarity, the ethyl acetate extract from the stems of Mangifera reba, collected from Dong Nai province in 2014, five flavonoids (−)-naringenin (1), (−)-eriodictyol (2), (+)-taxifolin (3), kaempferol (4) and quercetin (5) were isolated. The chemical structures of these compounds were elucidated based on the MS, NMR spectroscopic analysis and comparison with the literature. All 5 isolated compounds with IC50 values of 4.3−84.9 μM showed more potential inhibitory activity than the positive control acarbose (IC50, 214.5 μM).

   Published: 2024-09-30In press
9. Original Research

   Studying the impact of autophagy inhibition by chloroquine to primary hepatic stellate cell activation in vitro

   Phạm T.,ân Phan N.,ân Lê T.,ìn., Đặng T.,àn., Hải Nhung T.ươn.

   This paper presented the isolation of primary hepatic stellate cell (HSC) to investigate the effects of chloroquine (CQ) on autophagy during the primary hepatic stellate cell activation in vitro. After isolation, HSC cells were evaluated for the isolation efficiency through the cell number and specific characteristics of HSC cells, such as cell size, lipid droplet storage capacity by Oil Reo O (ORO) staining, Desmin expression by Immunocytochemistry (ICC) staining, and morphological changes during HSC culture in vitro. The HSC after being isolated for 1 day were treated with CQ 10 μM for 24 h. The ability of CQ to inhibit the autophagy and prevent HSC activation in vitro was assessed through their morphology and the expression levels of LC3, P62, α-SMA, Collagen I (COL I) by ICC staining. The results showed that CQ 10 μM inhibited the autophagy via increasing the expression of LC3 (43.31 ± 1.61%) and P62 (61.28 ± 2.64%) compared with the control at day 2. CQ 10 μM also prevented HSC the activation in vitro through the incomplete transformation of myofibroblast-like cells and decreased expression of α-SMA (24.17 ± 7.40%) and COL I (18.05 ± 0.49%) at day 7 compared with the control. This result could be one step in determining the relationship between the autophagy and HSC activation, aiming to develop therapy targeting autophagy in the treatment of liver fibrosis.

   Published: 2024-09-30In press
10. Original Research

    The concentrations of toxic elements in tuna (Thunnus albacares) caught in Quy Nhon sea, Binh Dinh province analyzed by total relection X-ray fluorescence spectroscopy

    Van Hai N., Thi Minh Sang N., Quang Thi N., Sơn N.ễn A.

    Tuna (Thunnus albacares) contains omega-3 fatty acids that help improve heart health and reduce cholesterol. Yellowfin tuna also has high protein content and low calories. However, some harmful elements, if present in large quantities in tuna meat, could affect consumers’ health. According to the World Health Organization (WHO), four elements including arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) are classified as toxic elements in category A. This paper presents the use of total reflection X-ray fluorescence spectroscopy (TXRF) to analyze the concentration of these elements in the fresh muscle tissue of tuna collected at Dam Market, Quy Nhon City, Binh Dinh Province. The results showed that the concentration of toxic elements in the fresh tuna muscle samples were: As (inorganic arsenic compounds): 0.05 ± 0.02 mg.kg-1 , Cd: 0.03 ± 0.01 mg.kg-1 , Pb: 0.08 ± 0.02 mg.kg-1. As stated by the European Food Safety Authority (EFSA), the estimated daily intake (EDI) allowances for the above elements were as follows: As (inorganic arsenic compounds), Cd, Pb, and Hg should not exceed 0.3, 1.0, 0.4 and 0.3 µg.kg-1 body weight/day, respectively. The calculated EDIs in this observation were: i/ As inorganic arsenic compounds for adults: 0.037 µg.kg-1 body weight/day, children: 0.133 µg.kg-1 body weight/day ii/ Cd: adults: 0.022 µg.kg-1 body weight/day, children: 0.080 µg.kg-1 body weight/day. iii/ Pb for adults: 0.059 µg.kg-1 body weight/day, children: 0.21 µg.kg-1 body weight/day. Similarly, for Hg, the average concentration in this observation was below the lower limit of detection and permissible value. The EDI was lower than the reference value in most studied tuna samples (93%), specifically for adults: 0.081 µg.kg-1 body weight/day, children: 0.293 µg.kg-1 body weight/day. There were 2 samples that exceeded the European food safety standards, with levels of 0.523 µg.kg-1 body weight/day and 0.877 µg.kg-1 body weight/day. Therefore, the analysis results of the concentration of four toxic elements in tuna samples purchased at Dam Market, Quy Nhon City, Binh Dinh Province showed the safety for consumers and could meet the European food safety standards.

    Published: 2024-09-11In press