Diversity depends on scale in the forests of the Central Highlands of Vietnam

Ha Thi Thanh Do,John C. Grant,Bon Ngoc Trinh,Heidi C. Zimmer,J. Doland Nichols 국립중앙과학관 2017 Journal of Asia-Pacific Biodiversity Vol.10 No.4

Tropical forests are among the most diverse and threatened ecosystems. The montane forests in the Central Highlands of Vietnam have outstanding biodiversity and unique species, yet we know little about them. This study characterised the natural forest in Dam Rong, Ha Nung and Yok Don. We identified six discrete communities and their indicator species. The Highland Floodplain forest had tree species richness of up to 22 species/400 m2 and 70 species/ha. The lowland forests of Yok Don had three distinct communities, despite having the lowest mean species richness (5 species/400 m2), highlighting that biodiversity should be assessed at multiple scales. This study illustrates the high species richness of the forests of Vietnam, and provides an important record of tree species (including rare and threatened species). Our community determinations can be used in future conservation management planning.

Four New Compounds Isolated from the Aerial Part of <i>Belamcanda chinensis</i> (L.) and Their Effect on Vascular Smooth Muscle Cell (VSMC) Proliferation

Ha, Do Thi,Binh, Bui Thi,Thu, Nguyen Thi,Bich Thu, Nguyen Thi,Thanh Tung, Pham Ha,Oh, Won Keun Pharmaceutical Society of Japan 2019 Chemical & pharmaceutical bulletin Vol. No.

Isolation and Cytotoxic Potency of Endophytic Fungi Associated with Dysosma difformis, a Study for the Novel Resources of Podophyllotoxin

Hoa Thi Tran,Giang Thu Nguyen,Hong Ha Thi Nguyen,Huyen Thi Tran,Quang Hong Tran,Quang Ho Tran,Ngoc Thi Ninh,Phat Tien Do,Ha Hoang Chu,Ngoc Bich Pham 한국균학회 2022 Mycobiology Vol.50 No.5

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes asso- ciated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC50 value of lower than 10 mg/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anti- cancer compound.

Factors Affecting Tourists’ Satisfaction in Associated Tourism Chains

Ha NGUYEN VAN,Thi Kim Hao DO,Thi Viet Ha NGUYEN,Ngoc Tien NGUYEN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.6

Tourism is an interdisciplinary, inter-regional, inter-territory integrated economy; therefore, the construction of an associated tourism chain will help localities in the region take greater advantage of tourism resources and tourism products to meet the diverse needs of visitors (UNWTO, 2013). This research seeks to identify the factors affecting the satisfaction of tourists in the associated tourism chain in four central provinces of Vietnam – Binh Dinh, Phu Yen, Gia Lai, and Dak Lak. The study surveyed 1,361 tourists who have participated in an affiliated tour chain in these provinces during the March–April 2020 period. The survey was conducted online with the help of Google Form and the data collected were processed using descriptive statistics, exploratory factor analysis, and regression analysis. The research results show that two main factors are affecting the satisfaction of tourists in the associated tourism chain in the above regions, namely, (i) tourism resources (cultural beauty in localities in the associated tourism chain, local cuisine in the affiliated travel chain, natural landscapes/local attractions in the linked tourism chain, etc.); and (ii) tourism environment (the climate in localities in the associated tourism chain, the clean and fresh environment in localities in the associated tourism chain, etc.).

Impact of Vocational Training on Wages of Ethnic Minority Labors in Vietnam

DO, Ha Thi Hai,MAI, Cuong Ngoc,MAI, Anh Ngoc,NGUYEN, Nui Dang,PHAM, Toan Ngoc,LE, Huong Thi Thu,TRAN, Manh Dung,VU, Tri Tuan Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.6

This research investigates the impact of vocational training on wages of ethnic minority labors in emerging countries; Vietnam is the case study. The study uses secondary data from 2014 to 2018 collected through Vietnam Household Living Standards Surveys (VHLSS) conducted by the General Statistics Office. In order to analyze the impact of vocational training on wages of ethnic minority areas in Vietnam, this research creates ethnic area variables. According to Vietnamese regulations, ethnic areas are communes of 51 different provinces, inhabited by ethnic minority people. The statistics from VHLSS in 2018, show that the proportion of labors of working age with a certificate was 22.5%. The research employs Heckman Sample Selection Model to estimate the impact of vocation training on wage of labors in ethnic minority areas. The results show that vocational training plays a crucial role in improving the wages of ethnic minorities and has a positive impact. However, apart from the achieved outcomes, vocational training and job creation for ethnic minorities are not without limitations and shortcomings. Based on the findings, some recommendations to ethnic minority labors, enterprises and the Government are proposed to encourage participation in vocational training for the purpose of promoting the efficiency of the labor market.

Functions of ABC transporters in plant growth and development

Do, Thanh Ha Thi,Martinoia, Enrico,Lee, Youngsook Elsevier 2018 Current opinion in plant biology Vol.41 No.-

<P>ABC transporters are essential for plant development, playing roles in processes such as gametogenesis, seed development, seed germination, organ formation, and secondary growth. ABC transporters are directly energized by ATP and can transport complex organic materials against concentration gradients; thus, they are uniquely suited to provide the complex building blocks required for the development of specialized plant cells. We review recent progress in our understanding of the contribution ABC transporters make to the growth and development of plants, including their roles in protective layer formation and in transporting phytohormones.</P> <P><B>Highlights</B></P> <P> <UL> <LI> ABC transporters are critical for plant growth and development. </LI> <LI> New alleles of known ABC transporters have revealed novel physiological roles. </LI> <LI> Studies of ABC transporters with substrate biosynthesis enzymes were fruitful. </LI> </UL> </P>

Stilbenes and Oligostilbenes from Leaf and Stem of Vitis amurensis and Their Cytotoxic Activity

Do Thi Ha,Quan Cheng Chen,Tran Manh Hung,Tran Minh Ngoc,Phuong Thien Thuong,김홍진,성연희,민병선,배기환,윤의중 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.2

Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-ε -viniferin (3), gnetinH (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)- ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC50 values ranging from 15.7 ± 2.1 to 30.9 ± 1.8 μM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC50 values of 30.6 ± 4.1 and 28.7 ± 2.81μM, respectively) and K562 (IC50 values of 38.6 ± 0.82 and 24.6 ± 0.76 μM, respectively). Gnetin H (4)showed only weak cytotoxic activity against L1210 with an IC50 value of 40.1 ± 4.23 μM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-ε -viniferin (3), (+)-ampelopsin F (7), and piceatannol(9) exhibited no activity on three cancer cell lines.

Adlay Seed Extract (Coix lachryma-jobi L.) Decreased Adipocyte Differentiation and Increased Glucose Uptake in 3T3-L1 Cells

Do Thi Ha,Trinh Nam Trung,Nguyen Hai Nam,Chu Van Men,Nguyen Bich Thu,Tran Thi Phuong,KiHwan Bae 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.6

The aim of the present study was to investigate effects of the ethyl acetate fraction of an ethanol extract of Coix lachryma-jobi (ECLJ) on glucose uptake and adipocyte differentiation in 3T3-L1 cells. ECLJ phosphorylated AMP-activated protein kinase (AMPK) and its downstream substrate acetyl-coenzymeA carboxylase in 3T3-L1 cells in a time- and dosedependent manner. Moreover, we discovered that compound C inhibits ECLJ-stimulated ACC phosphorylation. In addition,ECLJ exhibited a dose-dependent stimulation of glucose uptake in 3T3-L1 cells, and this increase was obviously attenuated by compound C. ECLJ also caused a decrease in the expression levels of adipogenesis factors such as fatty acid synthase, sterolregulatory-element-binding protein-1c, peroxisome proliferator-activated receptor g, and CAATT=enhancer binding protein a in a dose-dependent manner. Differentiation was examined by Oil red O staining activity after ECLJ treatment for 6 days. ECLJ decreased mean droplet size. These results suggest a possible role for AMPK in the process of adipose differentiation and that ECLJ targeted for adipocyte functions could be effective in improving the symptoms of metabolic syndrome.

Effects of Coumarins from Roots of Paramignya scandens (Griff.) Craib on LPS-induced IL-1β and IL-10 Cytokine Production in RAW 264.7 Macrophages

Thi Ha Do 한국생약학회 2024 Natural Product Sciences Vol.30 No.1

Based on our previous study, we evaluated the modulatory effects on LPS-induced IL-1β and IL-10 cytokine production in RAW 264.7 macrophages of several medicinal herbs, including P. scandens. The results showed that P. scandens extract showed significant effects on LPS-induced IL-1β and IL-10 cytokine production in RAW 264.7 macrophages. Therefore, in the current research, we focused on the P. scandens sample. Cytokine production effects bioassay-guided isolation of ethyl acetate fraction of 70% ethanol extract from roots of Paramignya scandens (XL) obtained seven coumarins (1–7). Their chemical structures were identified using spectroscopic methods (NMR and MS) and compared with those previously published data to be xanthyletin (1), luvangetin (2), clausenidin (3), nordentatin (4), dentatin (5), clausarin (6), and anisocoumarin E (7). This study represents the first report on the presence of compounds 3, 6, and 7 in the Paramignya genus and compounds 1 and 2 in XL. All isolates (1–7) exhibited significant inhibition of LPS-induced interleukin (IL)-1β production compared to the LPS 5 ng/mL control group, with IL-1β concentrations ranging from 42.77 to 69.76 pg/mL. Additionally, the IL-10 production induced by compounds 1‒7 in LPS-stimulated RAW 264.7 macrophages ranged from 175.98 to 321.56 pg/mL, demonstrating a marked increase as compared to the LPS 5 ng/mL control group. The stimulatory effect on IL-10 production and inhibitory effect on IL-1β production of compounds 1, 2, and 6 gradually increased with the test concentration in both RAW 264.7 macrophages and LPS-induced RAW 264.7 macrophages. Compounds 1, 2, and 6 inhibited IL-1β production in LPS-induced RAW 264.7 macro- phages with IC50 values of 10.70 ± 1.18 µM, 8.57 ± 1.05 µM, and 17.43 ± 1.05 µM, respectively. These findings highlight the potential of all the compounds derived from P. scandens roots in inducing IL-1β and IL-10 cytokines activity in LPS-stimulated RAW 264.7 macrophages. The results contributed to expanding the knowledge of the chemistry and bioactivities of P. scandens and provided valuable data for future investigations on this species.

Lipoxygenase Inhibitory and Antioxidant Activities of Isolated Compounds from Moutan Cortex

Do Thi Ha,Trinh Nam Trung,Nguyen Duy Thuan,NamHui Yim,민병선,배기환 한국생약학회 2010 Natural Product Sciences Vol.16 No.2

Phytochemical investigation on the ethyl acetate and n-butanol fractions of Moutan Cortex resulted in the isolation and characterization of a new monoterpene glycoside (3) and twenty known monoterpene glycosides (1, 2, 4 - 21). The structure of 3 was determined by spectroscopic data interpretation and physico-chemical properties. Compounds 1 and 8 presented a remarkable inhibitory activity against lipoxygenase-1 (LOX-1) with IC50 values of 45.2 and 37.5 mM, respectively. Compounds 9, 10, 13, 18, 19, and 21 showed significant 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect with IC50 values of 9.8, 25.5, 6.4, 15.2, 18.7, and 23.7 ?M, respectively. Benzoylpaeoniflorin (8), which exhibited the highest inhibitory effect with an IC50 value of 37.5 ? 0.7 mM, was further analyzed the inhibition kinetics by Lineweaver-Burk plots. Results indicated that 8 is a non-competitive inhibitor, and the kinetic parameter values were estimated to be (31.04 mM, Ki), (0.29 mM/min, Vm), and (48.50 mM, Km).