ISOLATION AND STRUCTURAL CHARACTERIZATION OF TWO SAPONINS FROM THE ROOTS OF Sansevieria trifasciata ‘Laurentii’

Sansevieria is a genus consisting of about 60 species natively distributed in tropical and subtropical areas. Many Sansevieria species are used for ornamental purposes or in traditional medicine to treat human diseases. Sansevieria trifasciata ‘Laurentii,’ commonly known as snake plant, is an evergreen perennial plant used in traditional medicine. The phytochemical investigation of the roots of S. trifasciata ‘Laurentii’ resulted in the isolation and structural characterization of two previously reported saponins: (24S,25R)-1b-[(β-D-fucopyranosyl)oxy]-3b-hydroxyspirost-5-en-24-yl β-D-glucopyranoside (1) and 26-[(β-D-glucopyranosyl)oxy]-3β,22α-dihydroxyfurosta-5,25(27)-dien-1β-yl-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (2) by analysis of their 1D and 2D NMR spectra and HR-ESI-MS, together with the comparison to data published in the literature

Morphology and DNA marker for distinguishing Paphiopedilum hangianum and Paphiopedilum emersonii from Vietnam

Genus Paphiopedilum has species having lovely flowers which are incredibly attractive to everyone. Their ornamental and commercial value caused over-collection and illegal poaching and trade. Due to these reasons, nowadays, the Venus slipper orchids are facing to deplete in nature. Therefore, it is important to consider these species conservation. Mainly, it is necessary to prioritize the identification and phylogenetic analysis methods of the genus Paphiopedilum which includes many species with similar morphological characteristics. Consequently, it isn't easy to distinguish the identical species of this genus when the plants are young or not yet fully flowering. Therefore, this study aimed to distinguish two Paphiopedilum species, i.e. P. hangianum and P. emersonii, which have similar morphological characteristics, through comparative morphological analysis and differences in DNA barcoding sequences. To solve the problem associated with species identifications, a morphological comparison table was created with the four DNA sequence markers matK, rbcL, rpoC1 and trnH-psbA. The results of the morphological analysis showed that P. hangianum and P. emersonii are significantly different from each other in the flower's characteristics. While the difference in leaf morphology of both selected species is found very little, it is also distinguishable upon careful comparison. Moreover, the DNA barcoding indicator gave accurate and rapid distinctions between the two species, even when     the plants are young or without flowers. Furthermore, this DNA barcoding can establish an evolutionary relationship between the two selected species and the other species of the genus Paphiopedilum. The results of this study also suggested that the indicator trnH-psbA is a suitable marker for distinguishing these two species and can be applied for the phylogenetic analysis of the genus Paphiopedilum in Vietnam

Pollen and seed morphology of cleome species (Cleomaceae) in Vietnam

Cleomaceae is a family that includes 18 genera distributed worldwide in tropical and temperate regions. Cleome L. is the largest genus having 207 species, widely distributed in tropical and subtropical regions (POWO 2019). In Vietnam, the genus is represented by four species Cleome rutidosperma DC., C. houtteana Schltdl., C. viscosa L. and C. gynandra L. The present study documents the pollen and seed characteristics of all four species of Cleome in Vietnam, and the data obtained using light microscope and scanning electron microscope are analyzed considering their importance in taxonomic delimitation and understanding their phylogenetic relationship. The results indicated a close relationship between different pollen and aperture types. The striking differences between the pollen shapes among different species of Cleome could be useful in taxonomic and evolutionary studies. Similarly, seed shape and surface characters provided important clues for their delimitation. Based on the pollen and seed morphological characteristics, a taxonomic key has been provided for easy identification of the Cleome species in Vietnam

RNAi-mediated resistance to SMV and BYMV in transgenic tobacco

Abstract Soybean mosaic virus (SMV) and bean yellow mosaic virus (BYMV) are two typical types of viruses that cause mosaic in soybean plants. Multiple viral infections at the same site can lead to 66% to 80% yield reduction. We have aimed to improve SMV and BYMV resistance in Vietnamese soybeans using gene transfer techniques under the mechanism of RNAi. In this study, we present newly generated transgenic tobacco plants carrying RNAi [CPi (SMV-BYMV)] resistance to the two types of viruses; 73.08% of transgenic tobacco lines proved to be fully resistant to SMV and BYMV. In addition, the number of virus copies in transgenic tobacco plants was reduced on average by more than 51% compared to the control plants (wild type). This promising result shows the potential of transerring the CPi (SMV-BYMV) structure in soybean to increase resistance of soybean to SMV and BYMV and advance the aims of antiviral soybean breeding in Vietnam

Cloning and sequencing of the genes encoding coat protein (CP) in Potato virus Y from Thai Nguyen province

Potato (Solanum tuberosum L.) is the most widely distributed crop in tropical and subtropical zones of the world. Among diseases potato viruses play major role in reducing the yield. PVX (Potato virus X), PVY (Potato virus Y), PLRV (Potato leaf roll virus), PVA (Potato virus A), PVM (Potato virus M), PVS (Potato virus S) are major viral diseases occurring in Vietnam. PVY (Potato virus Y) is the type member of the genus Potyvirus of the family Potyviridae. The virus has a long filamentous particle containing one single-stranded, positive sense RNA genome of approximately 9.7 kb. PVY is an important pathogen infecting potato, tobacco, tomato and other solanaceous plant species. Different potato PVY isolates occur that can be categorized in 5 groups: PVYO, PVYN, PVYNTN, PVYNWi and PVYC. In this paper we report cloning and sequencing of coat protein (CP) gene of PVY from Thai Nguyen potato. The CP gene of this isolate was found to be 801 nucleotides long, coding for 267 amino acids. Comparison amino acid of CP protein in potato from Thai Nguyen with ten sequences on NCBI showed that amino acid was 92.1-98.9% homology

BRAZILIAN ARCHIVES OF BIOLOGY AND TECHNOLOGY A N I N T E R N A T I O N A L J O U R N A L Cloning and Overexpression of GmDREB2 Gene from a Vietnamese Drought-resistant Soybean Variety

ABSTRACT This work studied the amplification, cloning and determination of the GmDREB2 gene from the soybean cultivar DT2008 and five Vietnamese local soybean cultivars (DT26, DT51, DVN5, CB, CBD) and designed the vector carrying the structure containing GmDREB2 gene from cultivar DT2008 (best drought tolerant). The coding region of GmDREB2 gene isolated from six soybean cultivars was 480 nucleotides in length, encoding 159 amino acids. The recombinant structure was designed as 35S-GmDREB2-c-myc and its expression was analysed in transgenic tobacco plants. Recombinant DREB2 protein was expressed in five transgenic tobacco lines with molecular weights close to 20 kDa. During the drought conditions, the proline accumulation of the transgenic tobacco lines was higher than on wild-type (WT) plant

Morphological characteristics of Talinum paniculatum, and nucleotide sequences of ITS region, rpoC1 and rpoB genes

Jewels of Opar (T. paniculatum) belongs to Talinum genus, Portulacaceae family which contains secondary metabolites such as phytosterols, saponins, flavonoids, tannins, steroids. These organic compounds have anti-viral effects and are very effective on Herpes’ disease and skin infections. Besides, Jewels of Opar can also be used as a supporting medicine for Parkinson’s disease, heart disease and for lowering blood cholesterols. Currently, the identification of T. paniculatum has been mainly based on morphological analysis. However, this method often encounters obstacles when T. paniculatum has been completely or partially processed. In this work, we present the results of morphological characteristics, taxonomy and sequences characterisation of ITS region and rpoC1, rpoB genes of T. paniculatum in Northern provinces of Vietnam. Tuberous roots of T. paniculatum are cylindrical with many small roots. The stems are upright and divided into several branches. The stems are upright and divided into several branches. The leaves are staggered, generally oval, ovate-oblong, or egg back shaped; thick, glossy with wavy veins, without hairs. The flowers of the plants have five reddish purple wings, two sepals, more than ten stamens, and a spherical ovary. The fruits are small, and the ripe fruit is ash gray in color. The seeds are very small, slightly flat, and black. Internal transcribed spacer (ITS) region and two partial sequences of rpoC1 and rpoB genes isolated from T. paniculatum plants are 643 bp, 595 bp and 518 bp in length, respectively. Based on the combination of the characteristics of morphology and nucleotide sequences of ITS region, rpoC1 and rpoB genes, the Jewels of Opar samples collected in some northern provinces of Vietnam were determined to belong to T. paniculatum species, Talinum genus, Portulacaceae family. Characteristics of sequences of ITS region and rpoC1, rpoB genes are valuable for exploiting DNA barcodes to identify T. paniculatum in Vietnam

Cloning and Overexpression of GmDREB2 Gene from a Vietnamese Drought-resistant Soybean Variety

ABSTRACTThis work studied the amplification, cloning and determination of the GmDREB2 gene from the soybean cultivar DT2008 and five Vietnamese local soybean cultivars (DT26, DT51, DVN5, CB, CBD) and designed the vector carrying the structure containing GmDREB2 gene from cultivar DT2008 (best drought tolerant). The coding region of GmDREB2 gene isolated from six soybean cultivars was 480 nucleotides in length, encoding 159 amino acids. The recombinant structure was designed as 35S- GmDREB2- c-myc and its expression was analysed in transgenic tobacco plants. Recombinant DREB2 protein was expressed in five transgenic tobacco lines with molecular weights close to 20 kDa. During the drought conditions, the proline accumulation of the transgenic tobacco lines was higher than on wild-type (WT) plants, with the rate from 211.17 to 332.44% after five days of drought stress, and from 262.79 to 466.04% after nine days of drought stress. The two lines, TG2 and TG12 had the highest increase rate. These results provided the basis to generate drought-tolerant soybean plants by GmDREB2 overexpression

Analysis of the Chloroplast Genome of Ficus simplicissima Lour Collected in Vietnam and Proposed Barcodes for Identifying Ficus Plants

Ficus simplicissima Lour. is an Asian species of fig tree in the family Moraceae. The chloroplast (cp) genome of F. simplicissima m3 was sequenced using the Pacbio sequel platform. The F. simplicissima cpDNA has a size of 160,321 bp in length, of which GC content accounts for 36.13%. The cp genome of F. simplicissima consists of a single large copy (LSC) with a size of 91,346 bp, a single small copy (SSC) with a size of 20,131 bp, and a pair of inverted repeats with a size of 24,421 to 24,423 bp. The cp genome of F. simplicissima has 127 genes, including 85 protein-coding genes, eight rRNA genes, and 34 tRNA genes; 92 simple sequence repeats and 39 long repeats were detected in the cpDNA of F. simplicissim. A comparative cp genome analysis among six species in the Ficus genus indicated that the genome structure and gene content were highly conserved. The non-coding regions show more differentiation than the coding regions, and the LSC and SSC regions show more differences than the inverted repeat regions. Phylogenetic analysis supported that F. simplicissima m3 had a close relationship with F. hirta. The complete cp genome of F. simplicissima was proposed as a chloroplast DNA barcoding for genus-level in the Moraceae family and the psbA-trnH gene region for species-level identification

Analysis of the Chloroplast Genome of <i>Ficus simplicissima</i> Lour Collected in Vietnam and Proposed Barcodes for Identifying <i>Ficus</i> Plants

Ficus simplicissima Lour. is an Asian species of fig tree in the family Moraceae. The chloroplast (cp) genome of F. simplicissima m3 was sequenced using the Pacbio sequel platform. The F. simplicissima cpDNA has a size of 160,321 bp in length, of which GC content accounts for 36.13%. The cp genome of F. simplicissima consists of a single large copy (LSC) with a size of 91,346 bp, a single small copy (SSC) with a size of 20,131 bp, and a pair of inverted repeats with a size of 24,421 to 24,423 bp. The cp genome of F. simplicissima has 127 genes, including 85 protein-coding genes, eight rRNA genes, and 34 tRNA genes; 92 simple sequence repeats and 39 long repeats were detected in the cpDNA of F. simplicissim. A comparative cp genome analysis among six species in the Ficus genus indicated that the genome structure and gene content were highly conserved. The non-coding regions show more differentiation than the coding regions, and the LSC and SSC regions show more differences than the inverted repeat regions. Phylogenetic analysis supported that F. simplicissima m3 had a close relationship with F. hirta. The complete cp genome of F. simplicissima was proposed as a chloroplast DNA barcoding for genus-level in the Moraceae family and the psbA-trnH gene region for species-level identification