Ngoc Nguyen

• Doctor of Philosophy
• Researcher at Dalat University

ARTICLE INFO ABSTRACT Received: 04/6/2024 This study aim to examine the phylogenetic relationship between Panax species (Araliaceae) of Vietnam using MIG-seq method based on Next Generation Sequencing platform. A total of 29 Vietnamese Panax samples, including five species, two varieties, and one sample of Panax ginseng as an outgroup, were utilize...

Magnolia braianensis (Gagnep.) Figlar is an endemic species native to Vietnam. To date, its essential oil's chemical composition and biological activity have not been studied. This study aimed to investigate the chemical composition and biological activities of the leaf essential oil from M. braianensis. The chemical composition was analyzed using...

An analysis was conducted on the essential oil extracted from the leaves of Magnolia bidoupensis utilizing GC‐MS, revealing thirty‐three constituents that account for 98.9% of the essential oil. The main components included pogostol (22.4%), δ‐selinene (16.2%), and α‐amorphene (14.7%). Bioassays were then performed to evaluate the oil's biological...

The essential oil from the leaves of Blumea densiflora var. hookeri was analyzed using GC–MS, and bioassays were performed. GC‐MS identified thirty‐four constituents, representing 98.7% of the oil composition. The major compounds identified in the oil were (E)‐caryophyllene (15.3%), viridiflorol (5.5%), trans‐dauca‐4(11),7‐diene (4.6%), spathulenol...

The study aimed to evaluate the efficiency of high extraction from the leaves of Blumea densiflora var. hookeri, distributed in Lam Dong by using ethanol solvent. It also investigated the chemical composition and antioxidant activity of the ethanol extract obtained from this species. The results show that the efficiency of ethanol extraction by the...

Loài chàm muồng (Indigofera cassioides Rottl. ex Bl.) và chàm bụi (Indigofera suffruticosa Mill.) là hai loài thực vật cho bột chàm phân bố nhiều ở khu vực Lâm Đồng. Trong đó, bột chàm mang màu chàm có nguồn gốc tự nhiên đã được con người sử dụng từ rất lâu đời để làm chất nhuộm và làm thuốc điều trị một số bệnh v.v… Tuy nhiên, chưa có nghiên cứu n...

Thu hải đường langbiang (B. langbiangensis) thuộc chi Begonia, họ Begoniaceae, có nguồn gốc từ núi Langbiang tỉnh Lâm Đồng. Cho đến nay, chưa có nhiều nghiên cứu về loài này, đặc biệt là các nghiên cứu về thành phần hóa học và hoạt tính sinh học của nó. Nghiên cứu này được thực hiện nhằm đánh giá sơ bộ thành phần hóa học và hoạt tính kháng khuẩn củ...

Quercus is the largest genus of the family Fagaceae in the world and the second-largest in Vietnam, with approximately 50 species. However, the phylogeny study of the Quercus genus in Vietnam has yet to be thoroughly explored. In this study, we utilize the genome-wide single-nucleotide polymorphisms (SNPs) data obtained through Multiplexed Inter Si...

ARTICLE INFO ABSTRACT Received: 11/12/2023 The genus Quercus L. is the largest within the Fagaceae family, comprising over 500 species that are widely distributed across Europe, North America, the Mediterranean, temperate deciduous forests in East Asia, and tropical montane forests in Southeast Asia. This study aimed to investigate the phytochemica...

Trong nghiên cứu này, thành phần hóa học của tinh dầu chiết xuất từ lá loài Gaultheria sleumeri Smitinand & P.H.(Benth.) ở Việt Nam đã được phân tích và đánh giá hoạt tính sinh học của chúng. Tinh dầu lá loài G. sleumeri thu được thông qua quá trình chưng cất lôi cuốn hơi nước, sau đó phân tích thành phần bằng phương pháp sắc ký khí khối phổ (GC-MS...

Nghiên cứu này nhằm đánh giá thành phần hoá học cũng như hoạt tính kháng vi sinh vật của tinh dầu loài dầu giun (Dysphania ambroisioides (L.) Mosyakin & Clemants) phân bố tại tỉnh Lâm Đồng. Phương pháp lôi cuốn hơi nước đã được sử dụng để tách chiết tinh dầu và phương pháp sắc ký khí - ghép khối phổ (GC-MS) để phân tích thành phần hoá học của tinh...

The oak trees of the genus Quercus have been a subject of study for centuries, and this book provides a comprehensive guide to the species of Quercus found in Vietnam. With its rich biodiversity and unique cultural heritage, Vietnam is home to many species of oak trees that are of great ecological and cultural significance. In this book, we introdu...

The premise of the study Though phenological studies in montane forests are important, particularly in tropical Asia where primitive angiosperms are found, the phenology in these forests is still poorly understood. To characterize the phenological patterns and reveal the relationships between meteorological factors and phenology, we observed the le...

DNA barcoding is a tool for species discrimination and identification which helps overcome the problem of identification that cannot be covered by morphological identification. Quercus is the second biggest genus of Fagaceae in Vietnam as well as Lam Dong province after Lithocarpus. However, the species discrimination study of the Quercus species i...

Quercus mangdenensis Binh & Ngoc, sp. nov. (Fagaceae) is newly described from Mang Den Town in the central highland of Vietnam. The new species is characterized by lanceolate to oblong-lanceolate leaves with entire margin, 1–5-fruited infructescence, larger fruit size 6–10.5 cm long, broadly bowl-shaped cupules enclosing 1/5 of the nut, bracts of c...

Lithocarpus pacoensis Ngoc & Son from Hoa Binh province, Northern Vietnam, was described and illustrated. The new species is similar to Lithocarpus komtumensis A. Camus and Lithocarpus laoticus (Hickel & A. Camus) A.Camus in having long petioles; big cupules, usually clustered in sets of three, flat apical, nearly completely enclosing the nut; nut...

In the present study, viscozyme L pre-treatment for aerial parts of Rosmarinus officinalis L. (rosemary), grown in Lam Dong province, was performed to evaluate the effective extraction of essential oils by hydro-distillation. Enzymatic pre-treatment with 1 g viscozyme L enzyme mixed with 5 mL sodium chloride 15% at 50 o C for 1 hour, followed by hy...

This study aimed to assess the chemical composition of essential oils of Elsholtzia blanda (Benth.) Benth. in Lam Dong Province, Viet Nam, and evaluate their biological activities. Essential oils obtained by hydro-distillation of the aerial parts of E. blanda were analyzed by gas chromatography-mass spectrometry (GC-MS). Thirty-one constituents wer...

A newly recorded Lithocarpus (Fagaceae) species for the flora of Vietnam, namely Lithocarpus encleisocarpus (Korth.) A.Camus was reported in this study. This species is most morphologically similar to L. dahuoaiensis Ngoc & L.V. Dung in having a completely entire leaf margin, solitary cupule, long stalks of fruits, deeply cup-shaped or turbinate cu...

Lithocarpus cadamensis Ngoc & Son, a new species of Fagaceae, is described and illustrated from Mt. Ca Dam, Tra Bong District, Quang Ngai Province, central Vietnam. The new species is characterized by its large leaf blades with long petioles, solitary and subsessile cupules which almost completely cover the nut, and spiny cupule scales, in a combin...

A new species, Quercus sontraensis Ngoc, Binh & Son is described from Son Tra Nature Reserve, Son Tra Peninsula, Central Vietnam. We examined the morphology and constructed a highly resolved phylogeny of Q. sontraensis and its relatives (including Q. langbianensis and Q. cambodiensis) using Multiplex ISSR genotyping by sequencing (MIG-seq). The mor...

Beilschmiedia bidoupensis (Lauraceae) is described from Bidoup-Nui Ba National Park in the southern highland of Vietnam. The new species is characterized by lanceolate terminal buds that are ca. 2.5 mm long without coriaceous scales and covered with whitish brown hairs, glabrous twigs, predominantly alternate leaves evenly arranged on branches, ell...

Identifying and protecting refugia is a priority for conservation management under projected anthropogenic climate change. We have two main objectives: the first is to explore the spatial (East Asia) and temporal (Last Glacial Maximum to year 2070) distribution patterns of dominant Castanopsis species of evergreen broad-leaved forests, also the rel...

Three new species, Lithocarpus bidoupensis Ngoc & Tagane, L. congtroiensis Ngoc & Yahara, and L. hongiaoensis Ngoc & Binh are described from Bidoup-Nui Ba National Park, Central Highland of Vietnam. Morphological analyses and Maximum likelihood tree based on genome-wide SNPs support the distinction of those species from the previously known taxa in...

A new species of Quercus (Fagaceae), Q. ngochoaensis, from Ba Vi National Park, Ha Noi, northern Vietnam is described and illustrated. This species is morphologically similar to Q. glauca in having glabrous twigs, cuneate leaf base, two or three fruits per infructescence, almost entire margin of lamellate rings on cupule except the lowest three rin...

We are delighted to publish this book, “A Picture Guide for the Flora of Bidoup-Nui Ba National Park I: Mt. Langbian”. To enrich our knowledge of the fora of Bidoup-Nui Ba National Park, seven botanical surveys were conducted in the protected area in 2012–2018. Among these surveys, this book focusing on the fora of Mt. Langbian was resulted fro...

The most comprehensive phylogenetic tree showing relationships among the large tropical genus Ardisia and related genera of subfamily Myrsinoideae (Primulaceae), based on nucleotide sequences of the nuclear ribosomal internal transcribed spacer (nrITS) region from 177 samples predominantly from the Neotropics, East Asia, Indo-China and Malesia is p...

A new species of Claoxylon (Euphorbiaceae), C. langbiangense, from Bidoup-Nui Ba National Park, Lam Dong Province, southern Vietnam, is described and illustrated. It resembles C. longifolium of Cam- bodia, NE India, Indonesia, Laos, Malaysia, Papua New Guinea, Thailand and Vietnam, but is distin- guished by its serrate-dentate leaf margin, larger s...

The Red List of Oaks 2020 provides and analyzes IUCN Red List assessments for the estimated 430 species in the genus Quercus—the most complete and comprehensive global analysis of extinction risk for oaks. The only previous global assessment of oaks was published in 2007 and included just 175 species (~40% of the genus; Oldfield and Eastwood, 2007)...

Fifteen new species of angiosperms, Ilex bidoupensis, I. hongiaoensis (Aquifoliaceae), Mastixia hongiaoensis (Cornaceae), Daphniphyllum hongiaoense (Daphniphyllaceae), Platea hongiaoensis (Icacinaceae), Neolitsea bidoupensis, N. hongiaoensis (Lauraceae), Nyssa bidoupensis, N. hongiaoensis (Nyssaceae), Eriobotrya hongiaoensis, Prunus hongiaoensis (R...

In the present study, chemical composition and antibacterial properties of essential oil obtained from the aerial parts of the Melicope pteleifolia (Champ. ex Benth.) T.G Hartley in Dalat were evaluated. Essential oil was isolated through hydro-distillation. Twenty-nine constituents comprising 100% of the essential oil were characterized by gas chr...

Phenology of tropical montane forests has been less well studied than tropical lowland forests. To bridge this gap, five plots were installed along the elevation from 1460 m to 1920 m in Bidoup-Nui Ba National Park in southern Vietnam, where monthly average temperature fluctuated from 14.7 ºC to 18.0 ºC with the difference of only 3.3 ºC, and month...

Castanopsis dongnaiensis T.S. Hoang & V.N. Nguyen sp. nova (Fagaceae) from Dong Nai Culture and Nature Reserve, Dong Nai Province of Vietnam is described and illustrated. It is morphologically similar to C. ferox, but can be distinguished from it by its leaf margins which are serrate on 1/3 to the apex, a symmetric leaf base, cupule with decurved s...

Erythroxylum calyptratum, sp. nov. (Erythroxylaceae), from Mt. Fansipan, Hoang Lien National Park, Lao Cai Province, northern Vietnam, is newly described. The new species is characterized by thinly chartaceous leaves with 2–3 mm long petiole, 1–3 flowered inflorescences, downward facing white flowers, well-developed petal appendages (1/3–1/2 length...

Lasianthus cambodianus Pit. (Rubiaceae) is discovered from hill evergreen forest in Ngoc Linh Nature Reserve, Kon Tum province, Central Highland of Vietnam and reported here as a new record for the flora of Vietnam. Lasianthus cambodianus is morphologically similar to L. giganteus which is known from Bokor National Park, Kampot province, Cambodia;...

The taxonomy of Quercus langbianensis and its relatives in Vietnam and Cambodia have been revised based on evidence obtained from field observations, morphological comparison of herbarium specimens and molecular analyses using both classic and next generation DNA markers. Based on Bayesian inference using rbcL, matK and ITS regions and Neighbour-jo...

Lithocarpus vuquangensis Ngoc & Hung is described from Vu Quang National Park, North Central Vietnam. The morphological comparison and phylogenetic analysis based onrbcL,matKand ITS provided evidence that the new species was not assignable to any of the previously known taxa in Vietnam and its surrounding countries. The description, photographs, pr...

A new species, Quercus xuanlienensis Binh, Ngoc & Bon, is described from Xuan Lien Nature Reserve, Vietnam. The new species is morphologically similar to Q. edithiae Skan, in having 8–11 pairs of secondary veins, bowl-shaped cupules and ellipsoid to cylindrical-ellipsoid and basally convex nuts. It differs in having serrulate leaf margins only at a...

Macrosolenbidoupensis Tagane & V.S.Dang, sp. nov. (Loranthaceae) is newly described from Bidoup Nui Ba National Park in Lam Dong Province, southern Vietnam. The new species is characterized by small broadly elliptic to circular leaves, sessile to short petioles, slightly cordate to rounded leaf bases, 4–5 pairs of lateral veins and a basally green...

A new species, Garcinia hopii H.Toyama & V.S.Dang is described from Bidoup Nui Ba National Park, southern Vietnam. This species is similar to Garcinia hendersoniana Whitmore but differs from that species in having larger leaves, clustered pistillate flowers, a greater number of sterile anthers and a larger stigma of young fruits. A description, pre...

Lasianthus giganteus Naiki (Rubiaceae), first found in Cambodia, was recently discovered in central Vietnam and southern Thailand. We describe the floral morphology of this species for the first time.

Lithocarpus dahuoaiensis Ngoc & L. V. Dung, a new species from the Central highland of Vietnam, is described and illustrated. The new species is morphologically similar to Lithocarpus macphailii (M. R. Hend.) Barnett or Lithocarpus encleisocarpus (Korth.) A. Camus in having completely entire leaf margin, solitary cupule, long stalks of fruits, deep...

A new species, Popowia bachmaensis Ngoc, Tagane & Yahara, sp. nov. is described from Bach Ma National Park in ua ien Hue Province, Central Vietnam. is species is morphologically similar to Popowia pisocarpa (Blume) Endl. ex Walp., but can be readily distinguished from it by its lower stems, smaller leaves, shorter owering pedicels, shorter carpels,...

A new species, Callicarpa bachmaensis Soejima & Tagane, sp. nov., is described and illustrated from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species has a characteristic liana habit, white corolla, and narrowly elliptic to narrowly lanceolate, entire, occasionally subequal leaves, by which it is clearly distinguished...

Homalium glandulosum Tagane & V. H. Nguyen, from Vu Quang National Park in northern Vietnam, is newly described. This species is characterized by distinct glands, often stalked, at the base of the lamina and along the margin of the stipules and bracteoles. Illustrations, DNA barcodes of the two regions of rbcL and matK, and a key to the species of...