Exploring Two Streptomyces Species to Control Rhizoctonia solani in Tomato

Streptomyces species are effective biocontrol agents toward many plant pathogens. These microorganisms are well known for producing secondary metabolites, promoting plant growth and inducing plant defense mechanisms. In this study, the ability of tomato root-colonizing Streptomyces strains to trigger the resistance against Rhizoctonia solani (J.G. Kühn) AG4 was investigated. For this goal, we evaluated the pattern of LOXB and PAL1 genes expression changes upon pathogen inoculation in primed tomato plants. The results revealed that Streptomyces globisporous (Krasil'nikov) strain F8 and S. praecox (Millard and Burr) strain R7 were able to enhance the expression of lipoxygenase and phenylalanine ammonia lyase in tomato plants. This finding suggests that Streptomyces strains F8 and R7 may trigger jasmonic acid and phenyl propanoid signaling pathways in plants, therefore, resulting an induced defense status in tomatoes against R. solani. Biochemical characterization of these Streptomyces strains showed that they were strong producers of siderophores. S. praecox strain R7 produced siderophores of hyderoxamate and catechol types and S. globisporous strain F8 produced a phenolic siderophore. Moreover, they also produced protease while only the S. praecox strain R7 was able to produce amylase. Taken together, these results indicate that S. globisporous strain F8 and S. praecox strain R7 promote plant growth and reduces disease and hence are suitable for future in depth and field studies with the aim to attain appropriate biocontrol agents to protect tomatoes against R. solani.

Molecular Programming of Drought-Challenged Trichoderma harzianum-Bioprimed Rice (Oryza sativa L.)

Trichoderma biopriming enhances rice growth in drought-stressed soils by triggering various plant metabolic pathways related to antioxidative defense, secondary metabolites, and hormonal upregulation. In the present study, transcriptomic analysis of rice cultivar IR64 bioprimed with Trichoderma harzianum under drought stress was carried out in comparison with drought-stressed samples using next-generation sequencing techniques. Out of the 2,506 significant (p < 0.05) differentially expressed genes (DEGs), 337 (15%) were exclusively expressed in drought-stressed plants, 382 (15%) were expressed in T. harzianum-treated drought-stressed plants, and 1,787 (70%) were commonly expressed. Furthermore, comparative analysis of upregulated and downregulated genes under stressed conditions showed that 1,053 genes (42%) were upregulated and 733 genes (29%) were downregulated in T. harzianum-treated drought-stressed rice plants. The genes exclusively expressed in T. harzianum-treated drought-stressed plants were mostly photosynthetic and antioxidative such as plastocyanin, small chain of Rubisco, PSI subunit Q, PSII subunit PSBY, osmoproteins, proline-rich protein, aquaporins, stress-enhanced proteins, and chaperonins. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis states that the most enriched pathways were metabolic (38%) followed by pathways involved in the synthesis of secondary metabolites (25%), carbon metabolism (6%), phenyl propanoid (7%), and glutathione metabolism (3%). Some of the genes were selected for validation using real-time PCR which showed consistent expression as RNA-Seq data. Furthermore, to establish host–T. harzianum interaction, transcriptome analysis of Trichoderma was also carried out. The Gene Ontology (GO) analysis of T. harzianum transcriptome suggested that the annotated genes are functionally related to carbohydrate binding module, glycoside hydrolase, GMC oxidoreductase, and trehalase and were mainly upregulated, playing an important role in establishing the mycelia colonization of rice roots and its growth. Overall, it can be concluded that T. harzianum biopriming delays drought stress in rice cultivars by a multitude of molecular programming.

Chemical constituents of the ethyl acetate extract from the leaf of mugwort (Artemisia vulgaris L.)

Introduction: Mugwort (Artemisia vulgaris L.) is a familiar herbal medicine and also a daily vegetable. It is one of the ingredients in the famous remedy "Cao ích mẫu" specializing in menstrual disorders or the omelet with mugwort that helps save blood flow to the brain to treat headaches. In both traditional medicine and the new drugs, diseases are usually treated by mugwort as diabetes, epilepsy combination for psychoneurosis, depression, irritability, insomnia, anxiety, and stress. To demonstrate the medicinal uses, the chemical constituents of this herbal were continually studied. Methods: The leaves of mugwort were collected in Ba Ria - Vung Tau province, Vietnam. The plant was identified by the late pharmacist and botanist Binh Duc Phan. A voucher specimen (AV001) was deposited in the herbarium of the Department of Organic Chemistry, VNUHCM–University of Science. Dried leaf powder of A. vulgaris (11 kg) was extracted with methanol and evaporated under reduced pressure to give a methanol extract (910 g), which was dissolved in methanol-water (1:9) and then successively partitioned with petroleum ether, chloroform, and ethyl acetate. From the previously researched ethyl acetate fraction, nine compounds were isolated: six known phenolic compounds (luteolin, 6-methoxyluteolin, eupatilin, o-coumaric acid, vanillic acid, and protocatechuic acid), sinapyl alcohol diisovalerate, vulgarin, and one new compound (artanoic acid). Results: In this research, ethyl acetate fraction was also studied. From subfraction EA4, six compounds were isolated by three skeletons: phenolic compounds (5,4′ -dihydroxyflavone and 4-hydroxyphenyl acetate), phenyl propanoid (methyl 2-O-b -D-glucopyranosylcoumarate and 2-O-b -D-glucopyranosylcoumaric acid) and uracil (5-methyluracil and uridine). The structure of the isolated compounds was determined to base on 1D, 2D NMR spectra, HR-ESI-MS, and comparison with published data. Conclusion: Particularly, four compounds (methyl 2-O-b -D-glucopyranosylcoumarate, 2-O-b -D-glucopyranosylcoumaric acid, 5-methyluracil, and uridine) were known for the first time from this species.

Expression Profiling of Candidate Genes for Insight to Pericarp Browning in Litchi (Litchi chinensis Sonn.)

Litchi (Litchi chinensis Sonn.), a subtropical fruit crop has high commercial value and consumer acceptance owing to its rich juicy aril and attractive bright red pericarp. Anthocyanin, the major pigment present in litchi pericarp reaches its maximum content in fully ripen fruit contributing to its bright red colour. Anthocyanin content in plants depends on the rate of biosynthesis, stability in the vacuoles and the rate at which it is degraded. The biosynthesis of anthocyanin occurs via an intricate phenyl propanoid pathway controlled by plethora of structural and regulatory genes. Several genes encoding enzymes responsible for anthocyanin synthesis have been isolated and characterised in different plants. Litchi fruit being highly perishable, exhibit relatively shorter postharvest shelf-life of 2–3 days at ambient conditions which in part can be attributed to the enzymatic and non-enzymatic degradation of anthocyanin. In contrast to the comprehensive understanding of molecular basis of anthocyanin synthesis, the studies on its catabolism or degradation are meagre. Polyphenols oxidases and peroxidases are the major enzymes responsible for anthocyanin degradation leading to the problem of pericarp browning. Laccase, an anthocyanin degradation enzyme expresses about thousand fold higher than the polyphenols oxidase in the pericarp with epicatechin as favourable substrate. A detailed study of the anthocyanin degradation pathway in litchi may be helpful in managing the problem of pericarp browning to preserve its bright red colour as well as to enhance the shelf life and marketability of this valuable fruit crop.

SKOPOLETIN SUATU SENYAWA FENILPROPANOID DARI EKSTRAK ETIL ASETAT UMBI UBI JALAR (Ipomoea batatas L.)

AbstrakTelah berhasil diisolasi senyawa golongan fenil propanoid dengan nama “skopoletin” dari ekstrak etil asetat umbi Ubi Jalar (Ipomoea batatas L.). Ekstraksi senyawa fenolik dilakukan dengan metode maserasi menggunakan pelarut metanol, dilanjutkan partisi menggunakan n-heksana dan etilasetat. Pemurnian dilakukan dengan kromatografi kolom gravitasi dan ktomatografi radial menghasilkan senyawa golongan fenil propanoid. Struktur skopoletin diidentifikasi berdasarkan data spektrum UV, 1D dan 2D NMR.Kata kunci : fenil propanoid, skopoletin, dan Ipomoea batatas L. AbstractPhenylpropanoid group compound has been isolated as “scopoletin” from ethylacetate extract of tuber flesh Sweet potatoes (Ipomoea batatas L.). Extraction of phenolic compound was done by maceration method using methanol solvent, then partition with n-hexana and ethylacetate, respectively. The process of purification using various chromatographic techniques yielded compound of phenylpropanoid group. Structure of scopoletin is identified based on UV, 1D, and 2D NMR spectra.Keyword : phenyl propanoid, scopoletin, dan Ipomoea batatas L.

Recent Advances in Applications of Acidophilic Fungi to Produce Chemicals

Processing of fossil fuels is the major environmental issue today. Biomass utilization for the production of chemicals presents an alternative to simple energy generation by burning. Lignocellulosic biomass (cellulose, hemicellulose and lignin) is abundant and has been used for variety of purposes. Among them, lignin polymer having phenyl-propanoid subunits linked together either through C-C bonds or ether linkages can produce chemicals. It can be depolymerized by fungi using their enzyme machinery (laccases and peroxidases). Both acetic acid and formic acid production by certain fungi contribute significantly to lignin depolymerization. Fungal natural organic acids production is thought to have many key roles in nature depending upon the type of fungi producing them. Biological conversion of lignocellulosic biomass is beneficial over physiochemical processes. Laccases, copper containing proteins oxidize a broad spectrum of inorganic as well as organic compounds but most specifically phenolic compounds by radical catalyzed mechanism. Similarly, lignin peroxidases (LiP), heme containing proteins perform a vital part in oxidizing a wide variety of aromatic compounds with H2O2. Lignin depolymerization yields value-added compounds, the important ones are aromatics and phenols as well as certain polymers like polyurethane and carbon fibers. Thus, this review will provide a concept that biological modifications of lignin using acidophilic fungi can generate certain value added and environmentally friendly chemicals.

Effects of Modulation of Ion Channel Currents by Salidroside in H9C2 Myocardial Cells in Hypoxia and Reoxygenation

Salidroside, a phenyl-propanoid glycoside isolated from the medicinal plant Rhodiola rosea, has potent cardioprotective effects, especially against myocardial hypoxia and reoxygenation injury. However, the molecular mechanism underlying its action is still unclear. The aim of this study was to determine the effect of salidroside on sodium channel current (INa) and transient outward potassium channel current (Ito) in H9C2 cardiomyocytes. H9C2 cells were subcultured under anoxic conditions to mimic myocardial hypoxia and subsequently treated with salidroside. Whole cell patch clamp was performed to determine the effect of hypoxia/reoxygenation and salidroside on myocardial electrophysiological properties. In the differentiated H9C2 cells, hypoxia/reoxygenation reduced INa and Ito amplitude, while salidroside significantly restored both and altered the INa and Ito activation/inactivation kinetics in a dose-dependent manner. Our findings demonstrate that salidroside protects myocardial cells against hypoxia-reoxygenation by restoring the function of sodium and potassium channels.

Identificación del ácido Rosmarínico a partir de Cordia Sebestena (Boraginaceae)

El ácido rosmarínico es un éster del ácido cafeico y el ácido 3,4-dihidroxifenil láctico, un fenil propanoide natural, que se encuentra principalmente en las especies de la familia Boraginaceae, la subfamilia Nepetoideae de la familia lameaceae y en algunas plantas inferiores como los helechos. Se aisló e identificó por primera vez a partir de Rosmarinus officinalis por dos químicos italianos, Scarpati y Oriente en 1958. Se realizó fraccionamiento ácido-base sobre el extracto hidroalcoholico crudo (ECH), con el propósito de obtener únicamente fracción de ácidos fuertes (Af). La misma se separó por cromatografía de columna para obtener la subfracción Af-1, a partir de la cual se aisló un sólido amarillo con PF 170 °C, el cual se caracterizó química y espectroscópicamente por UV, IR y RMN 1H, 13C y se identificó como ácido rosmarínico. Palabras clave: Boraginaceae, Cordia sebestena, fenoles, ácido rosmarínico. Abstract Different investigations on the Boraginaceae family have focused on the search for substances of proven pharmacological activity. The Cordia sebestena species, has not been studied as much, in a chemical and pharmacological way, so it is interesting to study this endemic plant in the western Venezuelan region. The plant material was collected in the city of Maracaibo, Zulia state. Raw hydroalcoholic extract was obtained from the fresh leaves by maceration with isopropanol-water (7: 3). By means of acid-base extraction, the fraction of strong acids was obtained. It was separated by column chromatography to obtain Af-1 subfraction, from which a yellow solid was isolated with mp 170 ° C, which was characterized chemically and spectroscopically by UV, IR and 1H, 13C NMR and identified as rosmarinic acid. Rosmarinic acid is an ester of caffeic acid and 3,4-dihydroxyphenyl lactic acid, a natural phenyl propanoid, which is found mainly in the species of the family Boraginaceae, the subfamily Nepetoideae of the family Lameaceae and in some lower plants such as Ferns. Keywords: Boraginaceae, Cordia sebestena, phenols, rosmaric acid.