VNUHCM Journal of Natural Sciences <p><span id="result_box" class="" lang="en"><span title="Tạp chí đã được phát hành tại các thư viện của các đơn vị thành viên của ĐHQG-HCM, các Sở Khoa học Công nghệ của các tỉnh thành trên cả nước và được Hội đồng học hàm Giáo sư Nhà nước đánh giá cao."><strong>Science and Technology Development Journal</strong> - <strong>Natural Science</strong> <strong>(STDJNS)</strong> (<strong>2588-106X</strong>) is the official journal of Viet Nam National University Ho Chi Minh City, Viet Nam, published by Viet Nam National University Ho Chi Minh City, Viet Nam. STDNS has been developed and separated from section of <strong>Nature Sciences</strong> of <strong>Science &amp; Technology Development Journal</strong> (<strong>STDJ</strong>) (<strong>1859-0128</strong>). From 2017, this section became a dependent journal with title <strong>Science and Technology Development Journal</strong> - <strong>Natural Science.&nbsp;</strong>STDJNS is a multiple discipline science journal covering from all fields of natural sciences included mathematics., computer science, chemistry science, physic, biology, environment, information technology...</span></span></p> <p><span id="result_box" class="" lang="en"><span title="Tạp chí Phát triển Khoa học và Công nghệ (PTKH&amp;CN) của Đại học Quốc gia thành phố Hồ Chí Minh (ĐHQG-HCM) được thành lập từ năm 1997, ra số đầu tiên vào tháng 1 năm 1998. Từ năm 2006 Tạp chí đã"><strong>Science and Technology Development Journal</strong> (STDJ), Vietnam National University - Ho Chi Minh City (VNU-HCM) was established in 1997. And the first issue was published in January 1998 with </span><span title="đăng ký mã số chuẩn quốc tế ISSN 1859-0128.">ISSN 1859-0128. </span><span title="Từ đó cho đến nay, Tạp chí PTKH&amp;CN đã trở thành diễn đàn khoa học quan trọng nhất của đội ngũ cán bộ nghiên cứu, giảng viên, nghiên cứu sinh của ĐHQG-HCM và cũng là diễn đàn khoa học công nghệ đáng tin cậy của">Since then, STDJ has become the most important scientific forum of scientists from VNU-HCM as well as</span><span title="nhiều nhà nghiên cứu, giảng viên các trường đại học khác tại Việt Nam."> other universities. </span><span title="Tạp chí đã trải qua 20 năm phát triển và đã trở thành nhịp cầu giao lưu khoa học, cũng như làm phong phú tài liệu tham khảo cho đội ngũ giảng viên, nghiên cứu sinh, sinh viên ĐHQG-HCM nói riêng và các Trường đại">The magazine has undergone 20 years of development and has become a bridge for scientific exchanges, as well as enriching reference materials for the faculty, doctoral students, students of VNU-HCM in particular and other universities, institutes...</span></span></p> <p><span id="result_box" class="" lang="en"><span title="Tạp chí đã được phát hành tại các thư viện của các đơn vị thành viên của ĐHQG-HCM, các Sở Khoa học Công nghệ của các tỉnh thành trên cả nước và được Hội đồng học hàm Giáo sư Nhà nước đánh giá cao.">STDJNS is a multiple discipline science journal covering from all fields of natural sciences included mathematics., computer science, chemistry science, physic, biology, environment, information technology... </span><br></span></p> <p><span class="" lang="en"><span title="• Khoa học Trái đất và Môi trường"><span id="result_box" class="" lang="en">&nbsp;</span></span></span></p> Viet Nam National University Ho Chi Minh City en-US VNUHCM Journal of Natural Sciences 2588-106X <p>Copyright The Author(s) 2018. This article is published with open access by Vietnam National University, Ho Chi Minh city, Vietnam. This article is distributed under the terms of the&nbsp;<a href="" target="_blank" rel="noopener">Creative Commons Attribution License (CC-BY 4.0)</a> which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.&nbsp;</p> Chemical constituents from aerial parts of Mussaenda saigonensis <p>The genus Mussaenda, belonging to the family Rubiaceae, comprising approximately 160 species, widely distributed in tropical and subtropical regions including Africa, Asia and Southeast Asia. 27 species were found in Viet Nam and several of them are used in folk medicine. An extensive survey of literature on phytochemicals and biological activities of Mussaenda indicated that most of the studies were on M. pubescens, M. macrophylla, M. frondosa, M. hirsutissima, M. arcuata. There are no reports on the chemical and biological data of the Mussaenda saigonensis. This paper reported the results of the isolation of some compounds from aerial parts of M. saigonensis. The dried powder of M. saigonensis aerial parts was exhaustively extracted with ethanol at room temperature to give the crude extract after evaporation of the solvent. This extract was applied to liquid‒liquid partition procedure and successively afford different polar extracts. Compound isolation was performed using column chromatography on silica gel. Chemical structures were elucidated by 1D, 2D-NMR, MS spectra and compared with the literature published data. Six compounds were isolated, including two triterpenoids, 2,3-dihydroxyurs-12-en-28-oic acid (1), 3,23-dihydroxyurs-12-en-28-oic acid (2), two phenolics, coumaric acid (3), caffeic acid (4) and two anthraquinones, aloe-emodin (5) and 11-O--rhamnopyranosylaloe-emodin (6). All compounds were the first reported for Mussaenda saigonensis.</p> Minh Nhat Phan Phat Tan Nguyen Khiem Huy Tran Dat Trong Bui Hau Van Tan Son Van Dang Tri Dinh Mai ##submission.copyrightStatement## 2023-11-12 2023-11-12 7 4 press press 10.32508/stdjns.v7i4.1276 title description none g A syntax‒aware deep‒learning model for biomedical semantic role labelling <p>A deep learning model for biomedical semantic role labeling was build. Semantic role labeling is a useful task that enables the computer to comprehend the key facts expressed in each sentence, and is a necessary first step in the resolution of several other semantic-related tasks, such as event extraction, entity extraction, and Q-A systems... Semantic role labeling is a domain-dependent task. In the biomedical field, semantics are transmitted via more intricate grammatical structures and dependencies in addition to being built on a predicate argument frameset that differs greatly from that of the general domain. To effectively account for these unique characteristics, three types of information were integrated into this deep learning model: Context knowledge obtained from a pre-trained language model trained on a substantial corpus of biomedical texts, dependencies derived from the dependency parse trees and sentence structure obtained from constituency parse trees. To handle grammatical information that is naturally represented as graphs, the Graph Attention Network which is well-known for its remarkable graph learning capabilities, was used. To further boost the model effectiveness, predicate indicator embedding was additionally included in the proposed model. According to experimental findings, the two above-indicated forms of syntactic information along with the predicate indicator embedding, could boost F1 by up to 20%.</p> Hoai Duc Tuan Nguyen Truong Duong Luu Quoc Duy Huynh ##submission.copyrightStatement## 2023-11-19 2023-11-19 7 4 press press 10.32508/stdjns.v7i4.1279 title description none g Electrochemical sensor for detection of uric acid using screen-printed electrodes modified with NiO/PANI-Graphene <p>Uric acid (UA) is a product of the catabolism of purine bases (adenine and guanidine) of nucleic acids that occurs naturally in the human body. The analysis of UA plays an important role in diagnosing and treating diseases such as gout, kidney stones, diabetes, heart disease, and Lesch-Nyhan syndrome. UA is analysed in the laboratory by the enzymatic colorimetric method with a time consuming of approximately one hour. Currently, electrochemical sensors are considered as a potential approach in the rapid quantification of UA due to the advantages of rapid analysis, low cost, few samples required for analysis, compact design and easy to use and do not require highly skilled technicians like traditional analytical methods. In this study, a commercial printed electrode (SPE) was surface-modified with a polyaniline-graphene (PANI-Graphene) composite coating and functionalize the surface of a PANI-Graphene film with a NiO electrochemical catalyst by cyclic voltammetry (CV) method. The fabricated electrode (designated NiO/PANI-Graphene/SPE) was used for UA analysis in a simulated human fluid medium (PBS, pH 7.4). The results show that the NiO/PANI-Graphene/SPE sensor electrode has good electrocatalytic activity for the oxidation of UA in the potential range of 0.3 to 0.5 V. Characteristically, the sensor has a wide linear range in the concentration range of 10 to 1750 μM with a high sensitivity of 29.5 μA mM1 cm2 and a low detection limit of 5.00 μM (S/N = 3). The NiO/PANI-Graphene/SPE sensor electrode has potential applications in the development of non-enzymatic electrochemical sensors for the rapid quantification of UA content in human body fluids.</p> Ngan Thi Kim Nguyen Y Ngoc Thi Dang Anh Hoang Nguyen Man Van Tran Hai Viet Le ##submission.copyrightStatement## 2023-11-19 2023-11-19 7 4 press press 10.32508/stdjns.v7i4.1286 title description none g Conversion of fructose to 5-hydroxymethylfurfural using 1,4-bis(4-sulfobutyl)-DABCO-1,4-diium tetrachloroaluminate ionic liquid in [CholineCl][Citric acid] deep eutectic solvent <p>In recent years, there has been a significant interest from both domestic and international researchers in ionic liquids as they are recognized as environmentally friendly solvents and catalysts. From 5-hydroxymethylfurfural (HMF), a substrate derived from carbohydrate, various important compounds particularly the 2,5-dimethylfuran can be synthesized because it could be used as a biofuel and valuable substance. Furan derivatives such as 5-alkoxymethylfurfural, 2,5-furandicarboxylic acid, 5-hydroxymethylfuroic acid, bis-hydroxymethylfuran and 2,5-dimethylfuran have significant applications in the fields of fuel and polymers. This paper presented the preparation of 8 ionic liquids containing Brønsted acid and Lewis acid site, intending to utilize them as catalysts for converting carbohydrates into 5-hydroxymethylfurfural (HMF). Several factors affecting the performance of HMF were investigated, including the type and catalyst loading, temperature, solvent, and reused. The results showed that 1,4-bis(4-sulfobutyl)-DABCO-1,4-diium tetrachloroaluminate (IL1) exhibited potential as a catalyst for the synthesis of HMF from fructose. This reaction was conducted at a temperature of 100℃ for 5 min with the yield of approximately 60% when using [CholineCl][Citric acid] deep eutectic solvent. This catalyst, IL1/[CholineCl][Citric acid], was successfully recovered and reused for four times. This demonstrated the efficacy of various ionic liquids as catalysts for the synthesis of HMF from fructose. Further study on this catalyst is needed for the application in the producing fuel precursors derived from carbohydrates on an larger scale.</p> Nguyễn Hào Trình Nguyễn Minh Nhật Nguyễn Phước Thiện Phan Bích Hà Phuong Hoang Tran ##submission.copyrightStatement## 2023-11-19 2023-11-19 7 4 press press 10.32508/stdjns.v7i4.1294 title description none g