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Two new steroidal saponins, 26

Aconitum carmichaelii Debx. is a medicinal plant that contains a variety of valuable medicinal substances, including flavonoids, alkaloids, and polysaccharides. Flavonoids are important substances because of their antioxidant, antiproliferative, and anticancer effects, but the flavonoid content in A. carmichaelii is low. Flavonoid 3′5′-hydroxylase (F3′5′H) is a key enzyme that catalyzes the final reactions in flavonoid biosynthesis in A. carmichaelii. Therefore, overexpressing the gene encoding of the F3′5′H enzyme to increase the flavonoid content in A. carmichaelii is a new direction in medicinal plant research strategies. In this work, the results of Agrobacterium tumefaciens–mediated genetic transformation of uidA and AcF3′5′H in A. carmichaelii plants, expression analysis of AcF3′5′H, and production of transgenic A. carmichaelii plants have been presented. Out of 180 transformed samples, 24 transgenic A. carmichaelii plants developed normally under greenhouse conditions. The results of PCR analysis of 15 transgenic A. carmichaelii plants showed that eight transgenic plants contained the AcF3′5′H transgene. Using electrophoresis SDS-PAGE, western blot, and ELISA techniques, we identified the expression of AcF3′5′H protein (rAcF3′5′H) in three transgenic plants. The rAcF3′5′H protein content of transgenic plants ranged from 0.2083 μg μL−1 (transgenic line T0-6) to 0.2507 μg μL−1 (T0-4). The highest concentrations of flavonoids, 773.50 ± 12.87, 661.73 ± 2.85, and 761.61 ± 9.10 μg g−1, were found in transgenic lines T0-4, T0-6, and T0-13, respectively. These values were higher than those of the non-transformed plants (wild-type). Our results demonstrate that compared with non-transgenic plants, overexpression of AcF3′5′H significantly increased the AcF3′5′H protein content in transgenic plants and the total flavonoid content in transgenic lines T0-4, T0-6, T0-13, from 39.13 to 63.63%. This is the first report of genetic transformation and an analysis of the expression enhancement of F3′5′H in the A. carmichaelii plant.

Dehydration responsive element binding proteins (DREB) are transcription factors linked to cis-acting elements of the promoter region, which regulate plant gene expression in response to abiotic stress. In this study, 69 DREB gene sequences of soybean from NCBI belonging to 18 GmDREB (Glycine max DREB) genes of 1 to 8 copies distributed on 17 chromosomes were identified in which GmDREB3 has 8 copies and the rest consisted of 1 to 4 ones. The motif PTPEMAARAYDVAALALKGPSARLNFPEL containing 11 points associated with the promoter of functional genes existed in 4 main types with the most popular one RGRRWKERRWT found in 13/18 DREB proteins was regarded as the popular AP2 domain of DREB protein. The phylogenetic tree based on the nucleotide sequences of GmDREB genes and the amino acid sequences of the AP2 domain expresses the evolution and relationship of the DREB subfamily in soybean. This study provides comprehensive information about the DREB subfamily, which formed the basis for experimental analyses to clarify the function of some members of this subfamily.

 Abstract. In Vietnam, experiential activities and experience-based learning models were first introduced in 2018 into the general education curriculum and they will be applied when implementing this program. Therefore, the teacher training program at university of education should meet the requirements of general education reform. In particular, it is essential to guide pedagogical students to design and organise experiential learning activities in the school. This study describes the design, implementation, and evaluation of a course of guiding to design and organise experience-based learning in schools for Vietnamese pedagogical students who will plan to implement experience-based learning activities into their teaching. A course in a 60-hour instructional process (including 30 hours of self-studying) with 5 activities designed to be experiential, enables our students to simultaneously explore and practice experience-based learning activities. The results of designing and organising 55 experience-based learning activity plans were obtained from one hundred and nine participants of the Faculty of Biology, Thai Nguyen University of Education, Vietnam who assessed the instructional process beneficially. The research group also proposed five effective measures to organise experiential learning in high school. This tutorial process will continue to be improved and implemented in subsequent courses to contribute to the renovation of higher education and meet the general educational improvement in Vietnam. https://doi.org/10.26803/ijlter.19.9.6

The dehydration responsive element binding (DREB) is a plant protein subfamily expressed when soybean plants face abiotic stresses. These DREB proteins are also considered to activate the transcription of drought-resistant genes. In this study, we present the determined results of relationships between overexpression of Glycine max DREB2 (GmDREB2) with the transcription level of Glycine max pyrroline-5-carboxylate synthetase (GmP5CS) gene, proline accumulation and drought tolerant ability transgenic soybean plants as the basis for selection of transgenic lines with high drought tolerance. GmDREB2 was inserted into a plant transgenic vector and the 35S-GmDREB2-cmyc construct was transferred into the soybean plants by Agrobacterium-mediated transformation. Recombinant GmDREB2 protein with a molecular weight of approximately 20 kDa was expressed in four transgenic soybean lines in the T1 generation. The GmP5CS gene was shown to have significantly (P

Isoflavones, which are secondary metabolites synthesised through the phenylpropanoid pathway, play important roles in many essential physiological processes of the soybean plant. Isoflavones are well-known for their antioxidant, antimicrobial, anti-inflammatory and anticancer activities; however, soybean plants contain very low amount of isoflavone. Therefore, increasing isoflavone content is one of major concerns in soybean research. An effective approach to enhance isoflavone content in soybean is by overexpression of the Glycine max chalcone isomerase 1A (GmCHI1A) gene. In this study, the GmCHI1A gene was transformed into soybean plants and the T2 generation was selected for high isoflavone content (daidzein, genistein) in transgenic soybean germs. GmCHI1A gene expression was enhanced in T1 transgenic lines, which led to an increase in recombinant CHI1A (rCHI1A) protein content. In soybean germs of the T2 transgenic lines, the content of daidzein and genistein increased from 166.46 to 187.23% and from 329.77 to 463.93%, respectively. Four T2 transgenic soybean lines (T2-1, T2-4, T2-21 and T2-24) with high daidzein and genistein content were selected for future progeny evaluation.

Two new steroidal saponins, 26-O-β-D-glucopyranosyl-22α-methoxy-5α-furost-25(27)-ene-1β,3β,26-triol 1-O-β-D-glucopyranoside (1), and 26-O-β-D-glucopyranosyl-22α-methoxy-furosta-5,25(27)-diene-1β,3β,26-triol 1-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranoside (2) were isolated and elucidated from the roots of Cordyline fruticosa (L.) A. Chev. Their structures were established by interpretation of spectroscopic data (1 D and 2 D NMR) and mass spectrometry (HR-ESI-MS).

Catharanthus roseus contains vincristine and vinblastine, which are outstanding drugs for cancer. In the biosynthetic pathways of terpenoid indole alkaloids (TIAs) in C. roseus, deacetylvindoline 4...

Plant defensins are divided into 18 groups and are multifunctional proteins. The Zea mays defensin 1 (ZmDEF1) gene encodes the defensin 1 protein, which can inhibit alpha-amylase in the insect gut. In this study, the ZmDEF1 gene was transferred into two maize cultivars, LC1 and LVN99, to improve weevil resistance in maize. The recombinant ZmDEF1 protein was assessed for its ability to inhibit alpha-amylase in the gut of the larvae of the maize weevil (Sitophilus zeamais Motsch.). ZmDEF1 was cloned into a pBetaPhaso-dest vector, which harbours phaseolin, a seed-specific promoter, and the Agrobacterium tumefaciens strain C58 harbouring the pBetaPhaso-ZmDEF1 vector was used to transfer the ZmDEF1 gene into two maize cultivars using immature embryos. Transformed calluses were selected on selection media containing kanamycin. The stable integration of the ZmDEF1 transgene into the transgenic maize plant genome was confirmed using Southern blotting. The recombinant ZmDEF1 protein of approximately 10 kDa was expressed in three transgenic maize lines from the LC1 cultivar (C1, C3, and C5) and two transgenic maize lines from the LVN99 cultivar (L1 and L3). The ZmDEF1 transgenic efficiency based on the results of PCR, as well as Southern and Western blotting, was 1.32% and 0.82%, respectively, which depends on the genotypes of LC1 and LVN99. The recombinant ZmDEF1 protein inhibited the alpha-amylase activity of the maize weevil larvae, and its ability to inhibit alpha-amylase is 54.52-63.09% greater than the ZmDEF1 protein extracted from non-transgenic plants.

Chitinases play the key role in hydrolysis of chitin, a huge organic carbon reservoir on earth, into monomeric sugars and their eventual conversion into valuable chemicals and energy sources. The Lecanicillium lecanii strain 43H was used as the source for the Endochitinase gene without signal peptide (mchit1). This mchit1 gene was cloned and sequenced. The recombinant Endochitinase non signal peptide was overexpressed in Pichia pastoris X33 with a level of 2.048 U mL−1 culture supernatant. The molecular mass of the purified recombinant Endochitinase (rmchit1) without signal peptide was 43 kDa. Metal ions, detergents, and organic solvents tested indicated a significantly influence on rmchit1 activity. The obtained results demonstrated that signal peptides affect the yield expression, purification methods, recovery as well as the physicochemical properties of the enzyme.

Jewels of Opar (Talinum paniculatum) is a herbaceous plant known for its highly medicinal value. This medicinal plant is listed in the Red List of Vietnam’s medicinal plants and in the handbook of Vietnam’s medicinal plants, both documents warranting its necessity for protection. Jewels of Opar contains bioactive substances such as phytosterols, saponins, flavonoids, tannins, steroids, and many other inorganic substances. Jewels of Opar plants collected in Thanh Hoa, Vietnam, are tree-like herbs, their green trunks grows straight up and then branch out. The shapes of the leaves vary; they are generally oval or ovate-oblong in shape, with wavy veins. The flowers of this tree have five reddish purple wings, two sepals, more than ten stamens, and a spherical ovary. Both the fruits and their seeds are small and black. Tuberous roots are cylindrical with many small roots, and the tubers themselves are sweet and spicy. Internal transcribed spacer (ITS) region isolated from T. paniculatum plants in Thanh Hoa, Vietnam is 643 bp in length. Based on the nucleotide sequences of the ITS region and using the basic local alignment search tool (BLAST) in theNational Center for Biotechnology Information (NCBI), the Jewels of Opar samples collected in Thanh Hoa, Vietnam were determined to belong to T. paniculatum species, Talinumgenus, Portulacaceae.

Talinum paniculatum plants contain flavonoids and saponins, which have strong antioxidant properties and are used in the treatment of numerous diseases, such as inflammation, allergies, and gastric ulcers. Currently, there is no published research on the flavonoid content of T. paniculatum plants; however, it has been determined that the species in the genus Talinum have very low flavonoid content, and therefore the effective approach to enhance the flavonoid content in T. paniculatum plants is overexpression of the Glycine max chalcone isomerase (GmCHI) gene. In this study, we analyzed GmCHI gene overexpression, which has increased total flavonoid content in transgenic T. paniculatum lines. We have successfully transformed T. paniculatum plants with the pCB301-GmCHI vector and created 2 lines in generation T1 (T1-2.2 and T1-10) with a transgenic frequency of 0.27%. Recombinant CHI protein expressed in transgenic lines has a molecular weight of approximately 25 kDa, and the concentration of this protein in the two transgenic lines T1-2.2 and T1-10 was 4.29 ?g mg?1 and 6.14 ?g mg?1, respectively. Total flavonoid contents of the two transgenic lines T1-2.2 and T1-10 were 4.24 mg g?1 and 2.74 mg g?1, respectively, which showed increases of 7.4-fold and 4.8-fold compared to that of the nontransgenic plants, respectively. Thus, overexpression of the GmCHI gene enabled T. paniculatum plants to improve their total flavonoid content. This work also confirmed the effectiveness of Agrobacterium-mediated plant transformation in enhancement of flavonoid accumulation in T. paniculatum plants.

Plant defensins are multifunctional small cysteine-rich proteins. They are active against fungi, bacteria, and many viruses, and they inhibit trypsin and α-amylase activities. In this study, we expressed the maize defensin gene (ZmDEF1) in tobacco seeds in order to establish the basis for generating transgenic maize plants resistant to weevils. The ZmDEF1 gene was isolated from Maison, a Vietnamese local maize cultivar, which is well known for having the highest resistance to weevils among other local cultivars. The ZmDEF1 gene was cloned into a binary vector, pBetaPhaso-dest, which carries phaseolin, a seed-specific promoter, to direct defensin expression in tobacco seeds. We obtained 13 transgenic tobacco lines from Agrobacterium-mediated transformation and regeneration, called the T0 generation. T0's seeds (called the T1 generation) were collected and analyzed for ZmDEF1 gene expression. Reverse-transcription polymerase chain reaction (RT-PCR) results showed that 4 out of 13 lines (T1-1, T1-3, T1-10, and T1-17) expressed the ZmDEF1 gene at the transcriptional level. These lines were further analyzed by real-time RT-PCR until their transcript expression could be identified. The results showed that the line T1-17 expressed it at the highest expression level. The western blot method also showed that ZmDEF1 was expressed in all four lines above. These transgenic seeds can inhibit maize weevils' α-amylase activity. Extracted protein from transgenic lines reduced weevil α-amylase activity by 67.9%-71.4% in comparison with protein extracted from nontransgenic plants. These results will hopefully provide a useful background to create transgenic maize plants with high resistance to weevils.

The EXP1 gene encodes expansin, which has the ability to loosen the plant cell wall. The soybean expansin gene GmEXP1 is activated specifically during the root elongation process, and thus it plays important roles in root development. During the drought period, changes in pressure within the cell and the fast development of the root allow plants to collect water from deep soil, which in turn helps plants grow and develop. In this study, we have successfully cloned and generated a GmEXP1 construct expressing recombinant expansin protein in tobacco plants. GmEXP1 is expressed in transgenic tobacco plants and passed on to the next generation. The transgenic tobacco plants have improved drought tolerance, which is demonstrated in both the length and volume of roots. From these promising results, we applied the same approach to generate drought-tolerant plants.