Phytochemical investigation of aerial parts of Woodsia ilvensis and its plasmin-inhibitory activity in vitro

The fern plant Woodsia ilvensis (L.) R. Br. belongs to the Woodsiaceae family and its leaves are used to treat diarrhea, soft-tissue injuries, and external injuries. Investigations of the compounds obtained from the plasmin-inhibitory-active extracts of W. ilvensis led to the isolation of two undescribed maleimide N-glycosides, an undescribed stilbenoid glycoside, and five undescribed acetylated flavonol bisdesmosides, together with 19 known compounds. The chemical structures of the isolated compounds were determined using spectroscopy. The absolute configurations of the sugar moieties were determined via HPLC after acid hydrolysis. Among the isolated compounds, some flavonoids and stilbenoid glycosides exhibited plasmin-inhibitory activity.

Phytochemical investigation of Scutellaria scordiifolia and its trypanocidal activity

Scutellaria scordiifolia Fisch. ex Schrank is used to treat various inflammatory diseases and other ailments in traditional and contemporary medicine. In this study, 10 undescribed compounds, including a flavanone (1), four chrysin C-glycosides (2-5), a phenanthrene glucoside (6), four iridoid glucosides (7-10) and 31 known compounds were identified from an extract of the aerial parts of S. scordiifolia. The absolute configurations of sugars in C-glycosides were determined by comparing electric circular dichroism spectra with calculated data. The flavanones (1 and 17), flavonols (11-13), flavone (14), and some of the flavone glucuronides (15, 16) exhibited trypanocidal activities against Trypanosoma congolense. The activity data and quantitative HPLC analysis of flavonoids from the aerial parts of S. scordiifolia suggest that they may effectively treat diseases caused by the aforementioned trypanosomes. Other compounds such as novel iridoids and phenanthrene glycosides, which may be useful for chemophenetic and chemoecological discussions, were also identified.

Methyl-β-D-glucopyranoside From Scabiosa comosa as a Quorum-Sensing Inhibitor

Quorum sensing (QS) is an important microbial signaling system that controls the expression of many virulence genes. Combination treatment with QS inhibitors and antibiotics may be the new treatment option for infectious diseases in the future. Therefore, there is an increasing need to discover anti-QS compounds to prevent antimicrobial resistance. We isolated methyl-β-D-glucopyranoside from Scabiosa comosa and found that it exerts an anti-QS activity against Chromobacterium violaceum CV026 without exhibiting any antimicrobial activity.

Actinocatenispora comari sp. nov., an endophytic actinomycete isolated from aerial parts of Comarum salesowianum

A novel actinomycete, designated NUM-2625^T, was isolated as an endophytic bacterium in aerial parts of Comarum salesowianum, an endemic species in the Altai, Himalaya mountain chain area, collected from Khasagt Khairkhan Mountain in Mongolia. The 16S rRNA gene sequence of strain NUM-2625^T showed the highest similarity to Actinocatenispora thailandica TT2-10^T (99.4 %), Actinocatenispora sera KV-744^T (99.3 %), and Actinocatenispora rupis CS5-AC17^T (97.7 %). Chemotaxonomic properties of strain NUM-2625^T were essentially consistent with those of the genus Actinocatenispora, such as the presence of meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan, MK-9(H₄) and MK-9(H₆) as the major menaquinones, and iso-C_16 : 0, iso-C_15 : 0, iso-C_14 : 0 3-OH, and anteiso-C_17 : 0 as the major fatty acids. Meanwhile, digital DNA-DNA hybridization and average nucleotide identity values revealed a low relatedness between strain NUM-2625^T and the other type strains of the genus Actinocatenispora. In addition, strain NUM-2625^T exhibited several phenotypic properties that could be used to distinguish it from its closest relatives. Based on the results of polyphasic analyses, strain NUM-2625^T represents a novel species in the genus Actinocatenispora, for which the name Actinocatenispora comari sp. nov. is proposed. The type strain is NUM-2625^T (=NBRC 114660^T=TBRC 13496^T).

Transcriptome Analysis of Chloris virgata, Which Shows the Fastest Germination and Growth in the Major Mongolian Grassland Plant

Plants in Mongolian grasslands are exposed to short, dry summers and long, cold winters. These plants should be prepared for fast germination and growth activity in response to the limited summer rainfall. The wild plant species adapted to the Mongolian grassland environment may allow us to explore useful genes, as a source of unique genetic codes for crop improvement. Here, we identified the Chloris virgata Dornogovi accession as the fastest germinating plant in major Mongolian grassland plants. It germinated just 5 h after treatment for germination initiation and showed rapid growth, especially in its early and young development stages. This indicates its high growth potential compared to grass crops such as rice and wheat. By assessing growth recovery after animal bite treatment (mimicked by cutting the leaves with scissors), we found that C. virgata could rapidly regenerate leaves after being damaged, suggesting high regeneration potential against grazing. To analyze the regulatory mechanism involved in the high growth potential of C. virgata, we performed RNA-seq-based transcriptome analysis and illustrated a comprehensive gene expression map of the species. Through de novo transcriptome assembly with the RNA-seq reads from whole organ samples of C. virgata at the germination stage (2 days after germination, DAG), early young development stage (8 DAG), young development stage (17 DAG), and adult development stage (28 DAG), we identified 21,589 unified transcripts (contigs) and found that 19,346 and 18,156 protein-coding transcripts were homologous to those in rice and Arabidopsis, respectively. The best-aligned sequences were annotated with gene ontology groups. When comparing the transcriptomes across developmental stages, we found an over-representation of genes involved in growth regulation in the early development stage in C. virgata. Plant development is tightly regulated by phytohormones such as brassinosteroids, gibberellic acid, abscisic acid, and strigolactones. Moreover, our transcriptome map demonstrated the expression profiles of orthologs involved in the biosynthesis of these phytohormones and their signaling networks. We discuss the possibility that C. virgata phytohormone signaling and biosynthesis genes regulate early germination and growth advantages. Comprehensive transcriptome information will provide a useful resource for gene discovery and facilitate a deeper understanding of the diversity of the regulatory systems that have evolved in C. virgata while adapting to severe environmental conditions.

Isolation and evaluation of trypanocidal activity of sesquiterpenoids, flavonoids, and lignans in Artemisia sieversiana collected in Mongolia

Artemisia sieversiana is an annual herbaceous plant distributed throughout Central and East Eurasia and is regarded as an undesirable forage plant in Mongolia. It affects livestock, so information about its chemical composition is needed. We isolated three new sesquiterpenoids (1-3) and known compounds from A. sieversiana and investigated their activities. The absolute configuration of 1 was established using single-crystal X-ray diffraction crystallography, and its configuration differed from those of reported compounds with similar structures. Two additional new sesquiterpenoids (2 and 3) with similar structures were identified, and their configurations were determined. The trypanocidal activities of the isolated compounds (1-18) against Trypanosoma congolense and the pathogen responsible for fatal trypanosomosis in animals were estimated. Flavonoids and lignans were identified as active compounds with IC₅₀ values ranging from 2.9 to 90.2 µM.

Flavonoids isolated from the flowers of Pulsatilla flavescens and their anti-piroplasm activity

Pulsatilla species are known as "Yargui", and their flowers are traditionally used in Mongolia as a tonic and for the treatment of inflammatory diseases. By chemical investigation of P. flavescens flowers, 21 flavonoids, including a new chalcone C-glucoside, chalconaringenin 2'-O-β-D-glucopyranosyl-5'-β-D-glucopyranoside, and two new flavanone C-glucosides, (2R)- and (2S)-naringenin 8-β-D-glucopyranosyl-4'-O-β-D-glucopyranoside, were isolated. The absolute configurations of the seven flavanone glucosides were elucidated by ECD spectra. For the isolated compounds, inhibitory activity against Babesia caballi and Theileria equi, which cause fatal diseases in horses, was estimated. Although most of the isolated chalcone and flavanone derivatives did not show any anti-piroplasm activity, all the isolated flavone and flavonol derivatives showed moderate effects against B. caballi and/or T. equi.

Trypanocidal Activity of 2,5-Diphenyloxazoles Isolated from the Roots of Oxytropis lanata

Eleven 2,5-diphenyloxazole derivatives (1-11), together with six known isoflavonoid derivatives, were isolated from the roots of Oxytropis lanata. The 2,5-diphenyloxazole (1) obtained proved to be identical to a standard sample used as a scintillator and liquid laser dye. The other oxazole derivatives isolated were found to have one to four hydroxy and/or O-methyl groups in their phenyl rings. Seven of the oxazole derivatives obtained are new (3-9). The inhibitory activity of the isolated compounds was evaluated against Trypanosoma congolense, the causative agent of African trypanosomosis in animals. Oxazoles with di- and trihydroxy groups showed trypanocidal activity, and 2-(2',3'-dihydroxyphenyl)-5-(2″-hydroxyphenyl)oxazole (4) exhibited the most potent inhibitory activity (IC₅₀ 1.0 μM).