Sephadex LH-20 Column Research Articles

A new sesquiterpene from stems of Buddleja lindleyana

The present study investigated the chemical constituents from the stems of Buddleja lindleyana. Ten compounds were isolated from the 95% EtOH extract of B. lindleyana stems by means of some techniques including polyamide, silica gel, MCI, Sephadex LH-20 column chromatography, and semi-preparative high-performance liquid chromatography(HPLC). Their structures were identified by spectral analysis and single-crystal X-ray diffraction as buddledin F(1), 6-O-4″-hydroxy-3″-methoxy-benzoyl ajugol(2), negundoin G(3),(+)-dihydrocubebin(4), 7-O-ethylguaiacylglycerol(5),(-)-jatrointelignan B(6), threo-1,2-bis-(4-hydroxy-3-methoxyphenyl)-propane-1,3-diol(7), vomifoliol(8), hinokinin(9), and isovanillic acid(10). Compound 1 was a new sesquiterpene named buddledin F. Compounds 3-8 were isolated from the Buddleja plant for the first time. The anti-inflammatory activities of compounds 1-10 in vitro were investigated, and the results failed to show the inhibitory activities of these compounds on the production of inflammatory factor NO.

A new xanthone from Hypericum lagarocladum

Repeated silica gel column chromatography, reversed-phase C_(18) column chromatography, Sephadex LH-20 column chromatography, high performance liquid chromatography and semi-preparative medium pressure liquid chromatography were performed to separate and purify the chemical constituents of Hypericum lagarocladum. Spectroscopic methods such as mass spectrometry(MS) and nuclear magnetic resonance(NMR) combined with physicochemical properties were adopted in identifying the structure of the isolated compounds. Ten compounds were isolated from the ethyl acetate fraction of H. lagarocladum and identified as lagarxanthone A(1), 1,7-dihydroxyxanthone(2), 3,4,5-trihydroxyxanthone(3), 2,7-dihydroxy-1-methoxyxanthone(4), 1,3-dihydroxy-7-methoxyxanthone(5), 1,5-dihydroxy-8-methoxyxanthone(6), 3,4-dihydroxy-2-methoxyxanthone(7), 3,4-dihydroxy-5-methoxyxanthone(8), 2,3-dimethoxyxanthone(9), and 2,3,4-trimethoxyxanthone(10). Among them, compound 1 was a new compound, and compounds 2-10 were isolated from this plant for the first time. These ten compounds were tested for glucose uptake in L6 cells, and the results showed that all the compounds had no significant effect on glucose uptake.

Insecticidal characteristics and structural identification of the potential active compounds from Streptomyces sp. KR0006: Strain improvement through mutagenesis.

Pest control by biological means is an effective, eco-friendly, and promising method that typically involves compounds naturally derived from actinomycetes. Thus, the present study aimed to screen, characterize, and identify the structure of insecticidal compounds from Streptomyces sp. KR0006 and increase the activity through mutagenesis. In the examination of the insecticidal activity level of the isolates, Streptomyces sp. KR0006 metabolite showed significant activity against larvae and moths of Plutella xylostella. Taxonomic analyses of the 16S rRNA gene sequences revealed that the isolated KR0006 strain tended to be 99% consistent with Streptomyces cinereoruber strain NBRC 12756. Three active compounds isolated from the culture filtrate of KR0006 were purified by solvent partition, mid-pressure liquid chromatography (MPLC), Sephadex LH20 column chromatography, and high-performance liquid chromatography (HPLC). By performing 1H-NMR, 13C-NMR, and 2D-NMR experiments, and high-resolution electrospray ionization mass spectrometry analysis, the 316-HP2, 316-HP3, and 316-HP5 compounds were inferred as antimycin A3a (MW, 519.; C26H36N2O9), antimycin A8a (MW, 534; C27H38N2O9), and antimycin A1a (MW, 548; C28H40N2O9) respectively. Mutant U67 obtained from exposure to ultraviolet (UV) irradiation (254 nm, height 17 cm) for 70 seconds resulted in a 70% more larval mortality than that of the initial wild culture. The second mutation of the culture broth enhanced insecticidal activity by 80 and 100% compared with the first mutation and initial medium, respectively. Our study found that Streptomyces sp. KR0006 strain produces insecticidal active compounds and could be used for practical pest management.

Chemical constituents from Artocarpus incisus and their inhibitory effects on proliferation of synoviocytes in vitro

The chemical constituents from the branches and leaves of Artocarpus incisus were isolated and purified via silica gel, ODS, and Sephadex LH-20 column chromatography as well as preparative HPLC. The chemical structures of all isolated compounds were identified in the light of their physicochemical properties, spectroscopic analyses, and comparisons of their physicochemical and spectroscopic data with the reported data in literature. As a result, 20 compounds were isolated and characterized from the 90% ethanol extract of the branches and leaves of A. incisus, which were identified as tephrosin(1), 6-hydroxy-6 a, 12 a-dehydrodeguelin(2), sarcolobin(3), lupiwighteone(4), 12-deoxo-12α-methoxyelliptone(5), 6 aα,12 aα-12 a-hydroxyelliptone(6), homopterocarpin(7), 3-hydroxy-8,9-dimethoxypterocarpan(8), pterocarpin(9), maackiain(10), medicarpin(11), calycosin(12), genistein(13), formononetin(14), 5-hydroxy-4',7-dimethoxy isoflavone(15), liquiritigenin(16), 4(15)-eudesmene-1β,7α-diol(17), ent-4(15)-eudesmene-1β,6α-diol(18), 1α-hydroxyisodauc-4-en-15-al(19), and guaianediol(20). Except compounds 13 and 16, all other compounds were isolated from the Artocarpus plants for the first time. Additionally, using MTS assay, compounds 1-20 were eva-luated for their anti-rheumatoid arthritis activities by measuring their anti-proliferative effects on synoviocytes in vitro. As a consequence, compounds 1-16 showed notable anti-rheumatoid arthritis activities, which displayed inhibitory effects on the proliferation of MH7 A synovial fibroblast cells, with the IC_(50) values in range of(9.86±0.09)-(218.07±1.96) μmol·L~(-1).

Bioactive secondary metabolites from two sponge-derived actinomycetes

Actinomycetes residing in marine habitat are an excellent treasure house of structurally novel and bioactive natural products with potent medicinal values. To exploit chemically diverse and bioactive natural products from actinomycetes living in underexplored ecological niche, we isolate a large number of marine actinomycetes from marine sponges, corals, algae, mollusks, sea grasses, and sediments collected from the South China Sea. In order to assess the values of these special marine actinomycetes in the green development of tropical agriculture, we screen the activity of marine actinomycetes against phytopathogenic fungi and bacteria. As a result, we identify two strains of sponge-derived actinobacteria <italic>Streptomyces</italic> sp. HMH1 and HML1 possessing antagonism effect against tested phytopathogenic microbes. The secondary metabolites produced by these two actinomycete strains and their anti-phytopathogenic fungi activity are investigated. The secondary metabolites from the fermentation extract of <italic>Streptomyces</italic> sp. HMH1 and HML1 are isolated and purified using various chromatography methods including silica gel column, reverse gel column and Sephadex LH-20 column chromatography. The structures of the isolated compounds are characterized by NMR, HR-ESI-MS spectroscopic data analyses and comparison with previously reported data. Three major compounds belonging to the family of actinomycin are purified from the solid fermentation extract of the sponge-derived actinobacterium <italic>Streptomyces</italic> sp. HMH1. They actinomycin D, actinomycin X₂, and actinomycin X_oβ. A compound identified as K-252d belonging to the family of indolocarbazole alkaloid is isolated from the solid fermentation extract of another sponge-derived actinobacterium <italic>Streptomyces</italic> sp. HML1. The anti-phytopathogenic fungi and bacteria activities of these compounds are evaluated against ten species of plant pathogenic fungi including <italic>Fusarium oxysporum</italic> FOC4, <italic>Lasiodiplodia theobromae, Phomopsis caricae-papayae</italic> Fetrak&amp;Cif., <italic>Corynespora cassiicola, Phytophthora capsica, Pythium aphanidermatum</italic> (Edson) Fitzp, <italic>Corynespora</italic> sp., <italic>Fusarium graminearum, Verticillium dahlia, Pestalotiopsis microspora</italic>, and two species of plant pathogenic bacteria including <italic>Xanthomonas oryzae</italic> pv. <italic>oryzae</italic> and <italic>Ralstonia solanacearum</italic>. The bioactivity test results of the compound against agricultural pathogens show that actinomycin D possesses inhibitory activity against the growth of these tested phytopathogenic fungi and bacteria. among which, actinomycin D has the most potent inhibitory activity against the plant pathogenic fungi <italic>Lasiodiplodia theobromae, Phomopsis caricae-papayae</italic> Fetrak&amp;Cif., <italic>Fusarium graminearum</italic> and <italic>Phytophthora capsica</italic>, with inhibitory rate of (60.09 ± 0.66)%, (48.82 ± 0.66)%, (46.47 ± 1.14)% and (44.13 ± 0.66)%, respectively. In addition, actinomycin D displays strong antibacterial activity on the plant pathogenic bacteria <italic>Xanthomonas oryzae</italic> pv. <italic>oryzae</italic> and <italic>Ralstonia solanacearum</italic> with bacteriostatic diameter at (36.00 ± 0.82) mm and (15.00 ± 0.47) mm, respectively. These results provide new compounds and bacteria resources for the development of high-efficiency biocontrol agents for agricultural disease control.

Several natural phytochemicals from Chinese traditional fermented food-pickled Raphanus sativus L.: Purification and characterization.

In this study, we aimed to isolate and identify the bioactive compounds from 5-year pickled radish. The pickled radish was extracted with methanol or ethyl acetate. Sephadex LH-20, normal phase and reverse phase silica gel column chromatography were used for separation and purification, combined with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), electrospray mass spectrometry (ESI-MS), nuclear magnetic resonance spectroscopy (NMR) technology for structural identification. The results showed that 6 compounds were separated and purified from methanol and ethyl acetate extracts of 5-year-old pickled radish. The structures were identified as 5-hydroxymethylfurfural, β-sitosterol, β-sitosterol-3-O-glucose glycosides, α-linolenic acid, 1-monopalmitin and chaenomic acid A. Using molecular docking, it was determined that β-sitosterol and its derivative β-sitosterol-3-O-glucose glycosides have high affinity for five antioxidant enzymes, and there were multiple hydrogen bonds between them. These results indicated that pickled radishes might be used as an important source of natural chemical substances.

Antioxidant Activity and Inhibitory Effects of Black Rice Leaf on the Proliferation of Human Carcinoma Cells.

The leaves of black rice, well-known as postharvest agricultural waste, contain a rich source of antioxidants with multiple benefits for human health. In the present study, the ethyl acetate fraction obtained from black rice leaf was separated into five subfractions using Sephadex LH-20 column chromatography, and their antioxidant and anticancer activities were investigated. The results revealed that among all the subfractions, subfraction 5 (Sub5) showed the highest total phenolic and flavonoid values. The antioxidant activity was also superior in Sub5 (the IC50 values are 3.23, 31.95, and 72.74 μg/mL, in the DPPH, ABTS, and reducing power assays, respectively) compared to the other subfractions. All subfractions, in a time-dependent manner, inhibited the proliferation of hepatoma (HepG2), breast (MCF-7), and colorectal (Caco-2) cancer cells, especially the Sub5. Thus, Sub5 was employed to conduct the cell cycle and cell apoptosis by flow cytometry. Sub5 significantly increased the accumulation of cells at the Sub-G1 phase in HepG2 cells (44.5%, at 48 h). Furthermore, it could trigger annexin V-detected apoptosis through mitochondrial and death receptor pathways accompanied by the suppression of PI3K/Akt and Erk signaling pathways. In addition, HPLC-DAD-MS/MS was conducted to characterize the bioactive constituents in the most potent antioxidant, cytotoxic, and apoptosis-inducing subfraction. Conclusively, Sub5 may have high potential as functional dietary supplements to inhibit the development of HepG2 liver cancer.

Development of Lepidium sativum Extracts/PVA Electrospun Nanofibers as Wound Healing Dressing.

Lepidium sativum L. (Garden cress/Hab El Rashad) (Ls), family Brassicaceae, has considerable importance in traditional medicine worldwide because of its antioxidant and anti-inflammatory activities. Ls fruits were used in Ayurvedic medicines as a useful drug for injuries, skin, and eye diseases. The aim of this study was to examine the effectiveness of the total ethanol extract (TEE) and polysaccharide (Poly) of Ls seeds loaded on poly(vinyl alcohol) (PVA) nanofibers (NFs) as a wound healing dressing and to correlate the activity with the constituents of each. TEE and Poly were phytochemically analyzed qualitatively and quantitatively. Qualitative analysis proved the presence of phenolic acids, flavonoids, tannins, sterols, triterpenes, and mucilage. Meanwhile, quantitative determinations were carried out spectrophotometrically for total phenolic and total flavonoid contents. High-performance liquid chromatography (HPLC) for TEE identified 15 phenolic acids and flavonoid compounds, with gallic acid and catechin as the majors. Separation, purification, and identification of the major compounds were achieved through a Puriflash system, column Sephadex LH20, and spectroscopic data (1H, 13C NMR, and UV). Eight compounds (gallic acid, catechin, rutin, kaempferol-3-O-rutinoside, quercetin-3-O-rhamnoside, kaempferol-3-O-rhamnoside, quercetin, and kaempferol) were obtained. Gas–liquid chromatography (GLC) analysis for Poly identified 11 compounds, with galactose being the main. The antioxidant activity for both extracts was measured by three different methods based on different mechanisms: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing ability of plasma (FRAP), and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS). TEE has the highest effectiveness as an antioxidant agent with IC50 82.6 ± 8.35 μg/mL for DPPH and 772.47 and 758.92 μM Trolox equivalent/mg extract for FRAP and ABTS, respectively. The PVA nanofibers (NFs) for each sample were fabricated by electrospinning. The fabricated NFs were characterized by SEM and Fourier transform infrared spectroscopy (FTIR); the results revealed successful encapsulation of TEE and Poly in the prepared NFs. Moreover, the swelling index of TEE in the prepared NFs shows that it is the most appropriate for use as a wound dressing. Cytotoxicity studies indicated a high cell viability with IC50 216 μg/mL and 1750 μg/mL for TEE and Poly, respectively. Moreover, the results revealed that nanofibers possess higher cell viability compared to solutions with the same sample quantities: 9-folds for TEE and 4-folds for Poly of amount 400 μg. The in vitro wound healing test showed that the TEE nanofibers performed better than Poly nanofibers in accelerating wound healing, with 90% for TEE, more than that for the Poly extract (82%), after 48 h. These findings implied that the incorporation of TEE in PVA nanofibers was more efficient than incorporation of Poly in improving the biological activity in wound healing. In conclusion, the TEE and polysaccharides of L. sativum L seed are ideal candidates for nanofibrous wound dressings. Furthermore, the contents of phenolic acids and flavonoids in TEE, which have potential antioxidant activity, make the TEE of L. sativum more favorable for wound healing dressing.

Indole Alkaloids and Chromones from the Stem Bark of Cassia alata and Their Antiviral Activities.

The Cassia (Leguminosae) genus has attracted a lot of attention as a prolific source of alkaloids and chromones with diverse structures and biological properties. The aim of this study is to screen the antiviral compounds from Cassia alata. The extract of the stem bark of this plant was separated using silica gel, MCI, ODS C18, and Sephadex LH-20 column chromatography, as well as semi-preparative HPLC. As a result, three new indole alkaloids, alataindoleins A–C (1–3); one new chromone, alatachromone A (4); and a new dimeric chromone-indole alkaloid, alataindolein D (5) were isolated. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Interestingly, alataindolein D (5) represents a new type of dimeric alkaloid with an unusual N-2−C-16’ linkage, which is biogenetically derived from a chromone and an indole alkaloid via an intermolecular nucleophilic substitution reaction. Compounds 1–5 were tested for their anti-tobacco mosaic virus (TMV) and anti-rotavirus activities, and the results showed that compounds 2–4 showed high anti-TMV activities with inhibition rates of 44.4%, 66.5%, and 52.3%, respectively. These rates were higher than those of the positive control (with inhibition rate of 32.8%). Compounds 1 and 5 also showed potential anti-TMV activities with inhibition rates of 26.5% and 31.8%, respectively. In addition, compounds 1–5 exhibited potential anti-rotavirus activities with therapeutic index (TI) values in the range of 9.75~15.3. The successful isolation and structure identification of the above new compounds provided materials for the screening of antivirus drugs, and contributed to the development and utilization of C. alata.

Isoquinoline alkaloids from two species of Thalictrum genus plants

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.

Gentiopicroside PLGA Nanospheres: Fabrication, in vitro Characterization, Antimicrobial Action, and in vivo Effect for Enhancing Wound Healing in Diabetic Rats

PurposeGentiopicroside (GPS), an adequate bioactive candidate, has a promising approach for enhancing wound healing due to its antioxidant and antimicrobial properties. Its poor aqueous solubility negatively affects oral absorption accompanied by low bioavailability due to intestinal/hepatic first-pass metabolism. Our aim in this study is to fabricate GPS into appropriate nanocarriers (PLGA nanospheres, NSs) to enhance its solubility and hence its oral absorption would be improved.MethodsNormal and ODS silica gel together with Sephadex LH20 column used for isolation of GPS from Gentiana lutea roots. Crude GPS would be further processed for nanospheres fabrication using a single o/w emulsion solvent evaporation technique followed by in vitro optimization study to examine the effect of two formulation variables: polymer (PLGA) and stabilizer (PVA) concentrations on the physical characterizations of prepared NSs. Possible GPS-PLGA chemical and physical interactions have been analyzed using Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The optimum GPS-PLGA NSs have been chosen for antimicrobial study to investigate its inhibitory action on Staphylococcus aureus compared with unloaded GPS NSs. Also, a well-designed in vivo study on streptozotocin-induced diabetic rats has been performed to examine the wound healing effect of GPS-PLGA NSs followed by histological examination of wound incisions at different day intervals throughout the study.ResultsThe optimum GPS PLGA NSs (F5) with well-controlled particle size (250.10±07.86 nm), relative high entrapment efficiency (83.35±5.71), and the highest % cumulative release (85.79±8.74) have increased the antimicrobial activity as it exhibited a higher inhibitory effect on bacterial growth than free GPS. F5 showed a greater enhancing impact on wound healing and a significant stimulating effect on the synthesis of collagen fibers compared with free GPS.ConclusionThese findings demonstrate that loading GPS into PLGA NSs is considered a promising strategy ensuring optimum GPS delivery for potential management of wounds.

Phenolic acids and flavonoids from Salvia plebeia and HPLC-UV profiling of four Salvia species

We isolated and purified phenolic acids and flavonoids from the ethanolic extract of Salvia plebeia using silica gel and a Sephadex LH-20 column chromatography. Spectroscopy revealed the isolated compounds were caffeic acid, rosmarinic acid, hispidulin, luteolin, jaceosidin, nepitrin, homoplantaginin, 6-hydroxyluteolin 7-O-glucoside, 6-methoxynaringenin 7-O-glucoside, naasanone, and cosmosiin. Quantitative analyses, using high-performance liquid chromatography coupled with UV (HPLC-UV), revealed that the major flavonoid from S. plebeia was 6-hydroxyluteolin 7-O-glucoside (100.63 mg/g) and the most abundant phenolic acid was rosmarinic acid (47.73 mg/g). Furthermore, among four other Salvia species, S. officinalis contained the highest overall phenolic acid and flavonoid level but these were still lower than S. plebeia. These results can help assess the potential of phenolic acids and flavonoids as potent sources of pharmacological ingredients from different Salvia species extracts.

Structural Characterization and Assessment of Anti-Inflammatory Activities of Polyphenols and Depsidone Derivatives from Melastoma malabathricum subsp. normale.

The roots of Melastoma malabathricum subsp. normale (D. Don) Karst. Mey have been used in traditional ethnic medicine systems in China to treat inflammation-triggered ailments, such as trauma, toothache, and fever. Therefore, the aim of this study is to screen for compounds with anti-inflammatory activity in the title plant. The extract of M. malabathricum subsp. normale roots was separated using various chromatographic methods, such as silica gel, ODS C18, MCI gel, and Sephadex LH-20 column chromatography, as well as semi-preparative HPLC. One new complex tannin, named whiskey tannin D (1), and an undescribed tetracyclic depsidone derivative, named guanxidone B (2), along with nine known polyphenols (2–10) and three known depsidone derivatives (12–14) were obtained from this plant. The structures of all compounds were elucidated by extensive NMR and CD experiments in conjunction with HR-ESI-MS data. All these compounds were isolated from this plant for the first time. Moreover, compounds 1–4, 8, and 10–14 were obtained for the first time from the genus Melastoma, and compounds 1, 2, and 11–14 have not been reported from the family Melastomataceae. This is the first report of complex tannin and depsidone derivatives from M. malabathricum subsp. normale, indicating their chemotaxonomic significance to this plant. Compounds 1–12 were investigated for their anti-inflammatory activities on the production of the nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and compounds 1, 11, and 12 showed anti-inflammatory activities with IC50 values of 6.46 ± 0.23 µM, 8.02 ± 0.35 µM, and 9.82 ± 0.43 µM, respectively. The structure–activity relationship showed that the catechin at glucose C-1 in ellagitannin was the key to its anti-inflammatory activity, while CH3O- at C-16 of aromatic ring A in depsidone derivatives had little effect on its anti-inflammatory activity. The study of structure–activity relationships is helpful to quickly discover new anti-inflammatory drugs. The successful isolation and structure identification of these compounds, especially complex tannin 1, not only provide materials for the screening of anti-inflammatory compounds, but also provide a basis for the study of chemical taxonomy of the genus Melastoma.

Isolation and characterization of some flavonoids from the leaf of Tapinanthus globiferus growing on Acacia nilotica

Tapinanthus globiferus is used ethnomedicinally for the treatment of bacterial infections, inflammation, stomach pain, ulcers among others. The aim of the study was to isolate bioactive compounds from the leaf of T. globiferus growing on Acacia nilotica. The powdered plant material was extracted with 90 % methanol using cold maceration and the resulting crude methanol leaf extract was partitioned into n-hexane, chloroform, ethylacetate and n-butanol fractions. The ethylacetate fraction was chromatographed on a silica gel, sephadex LH-20 column and preparative thin-layer chromatography. (-)-Epicatechin and Quercetin 3-O-β-D-glucopyranoside were isolated and characterized by means of physiochemical and spectroscopic (1D and 2D-NMR) analyses for the first time from T. globiferus growing on A. nilotica.&#x0D; Keywords: Tapinanthus globiferus; Flavonoids; Isolation; NMR&#x0D;

The chemical constituents of the n-hexane extract of Marchantia polymorpha L.

Introduction: Marchantia polymorpha belongs to the liverwort family. Marchantia species are known to possess diverse chemical constituents and bioactivities. As part of a chemically systematic study of liverworts, the isolation and structural elucidation of six compounds from Marchantia polymorpha were reported. Method: A dried powder of Marchantia polymorpha was macerated in methanol to prepare the crude extract. Then, the liquid–liquid partition method was applied to this extract to separate it into different polar extracts, including n-hexane, ethyl acetate extracts, and residue. The Sephadex LH-20 and silica gel column chromatography and recrystallization methods were used to isolate organic compounds. Their chemical structures were determined by usual techniques such as MS and NMR spectra interpretation in comparison with the experimentally spectroscopic data reported. Results: Six compounds consisting of marchantin G (1), quercetin (2), kaempferol (3), hexaconazole (4), indole-3-carboxylic acid (5), and sitosterol 3-O-β-D-glucopyranoside (6) were isolated. Conclusion: To the best of our knowledge, although all isolated compounds were known to be present in other species, they were reported from this species for the first time.

Chemical constituents of Scrophulariae Radix and their antitumor activities in vitro

The present study investigated the chemical constituents of Scrophulariae Radix and their antitumor activities in vitro. The compounds in the ethyl acetate extract were separated and purified by conventional column chromatographies(such as silica gel, Sephadex LH-20, and ODS column) and semi-preparative high-performance liquid chromatography(HPLC), and their structures were identified by various spectral techniques such as nuclear magnetic resonance(NMR) and mass spectrometry(MS). Twenty-three compounds were isolated and identified as benzyl-β-D-(3',6'-di-O-acetyl) glucoside(1), 5-O-p-methoxybenzoyl kojic acid(2), 5-O-methoxybenzoyl kojic acid(3), 7-O-methylbenzoyl kojic acid(4), 5-O-benzoyl kojic acid(5), methyl ferulate ethyl ether(6), trans-ferulic acid(7), trans-isoferulic acid(8), trans-caffeic acid(9), trans-caffeic acid methyl ester(10), caffeic acid ethyl ester(11), trans-cinnamic acid(12), trans-p-methoxycinnamic acid(13), trans-p-hydroxycinnamic acid(14), trans-p-hydroxycinnamic acid methyl ester(15), 2-(3,4-dihydroxyphenethyl) alcohol(16),(p-hydroxyphenyl) propanoic acid(17), coniferaldehyde(18), sinapaldehyde(19), benzyl β-primeveroside(20), 5-(hydroxymethyl) furfural(21), furan-2-carboxylic acid(22), and decanedioic acid(23). Among them, compound 1 is a new benzyl glucoside, compounds 2-4 are new pyranone compounds, compound 5 is a new natural product of pyranone. The NMR data of compounds 5 and 6 are reported for the first time. Compounds 6 and 20 were isolated from the Scrophularia plant for the first time. Compounds 8, 11, 14, 16, 18, 19, 22, and 23 were isolated from this plant for the first time. The in vitro cytotoxic activities of these compounds against three tumor cell lines(HepG2, A549, and 4 T1) were evaluated. The results showed that compounds 10 and 15 showed cytotoxic activities against HepG2 cells with IC_(50) values of(19.46±0.48) μmol·L~(-1) and(46.10±1.21) μmol·L~(-1).

Chemical constituents of cyclic peptides from fibrous roots of Pseudostellaria heterophylla

Four cyclic peptides were isolated from the 75% ethanol extract of the fibrous roots of Pseudostellaria heterophylla by silica gel, Sephadex LH-20 column chromatography, and semi-preparative HPLC. Through mass spectrometry, NMR and other methods, they were identified as pseudostellarin L(1), heterophyllin B(2), pseudostellarin B(3), and pseudostellarin C(4). Among them, compound 1 was a new cyclic peptide, and compounds 2-4 were isolated from the fibrous roots of P. heterophylla for the first time. None of these compounds displayed cytotoxic activities against MCF-7, A549, HCT-116, and SGC-7901 cells.

Online extraction and enrichment coupling with high-speed counter-current chromatography for effective and target isolation of antitumor anthraquinones from seeds of Cassia obtusifolia.

Traditional bioassay-guided investigation of bioactive compounds from natural products comprises critical steps, such as extraction, repeated column separation, and activity assay. Thus, the development of facile, rapid, and efficient technology is critically important. Here, a HepG2 cell-based extraction method was first developed to rapidly screen potential antitumor compounds from the seeds ofCassiaobtusifolia. Then, an online extraction and enrichment-high-speed counter-current chromatography (HSCCC) strategy was fabricated to facilely and efficiently isolate target antitumor compounds, which included direct extraction from solid C.obtusifolia, removal of polar interferences, enrichment of target compounds, and preparative isolation by HSCCC using flow rate stepwise increasing mode. After further purification by Sephadex LH-20 column, five antitumor anthraquinones, aurantio-obtusin, 1-desmethylaurantio-obtusin, chryso-obtusin, obtusin, and questin, were obtained for structural characterization and bioassay verification. The results may not only provide new perspectives for facile and rapid investigation of bioactive compounds from complex natural products, but also offer a scientific basis for the potential applications of C.obtusifolia.

A new cembranoid diterpene from Olibanum

Five compounds were isolated from the alcohol extract of Olibanum by MCI, silica gel, ODS, and Sephadex LH-20 column chromatographies and preparative high-performance liquid chromatography(HPLC). On the basis of spectral data and literature data, the compounds were identified as:(1S,3R,4S,7R,11S,12R)-1:12,4:7-diepoxisonane-8(19)-ene-3,11-diol(1), boscartin A(2),(+)-resinolin(3),(+)-5-hydroxy-3,4-dimethyl-5-pentylfuran-2(5H)-one(4), and acerogenin A(5). Compound 1 is a new compound, and compounds 3-5 were isolated from Olibanum for the first time. The structure of compound 1 was determined by spectroscopic analysis and single-crystal X-ray diffraction. Compounds 1 and 2 were tested for PC12 neurotoxicity, and the results showed that they were both safe compounds.

Evaluation of Scopoletin from Penicillium janthinellum Snef1650 for the Control of Heterodera glycines in Soybean.

Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is responsible for causing a major soybean disease globally. The fungal strain Penicillium janthinellum Snef1650 was evaluated against H. glycines. However, the effective determinants of the P. janthinellum strain are unknown. By performing pot experiments, a functioning compound was isolated from P. janthinellum Snef1650 through organic solvent extraction, semi-preparative HPLC, Sephadex LH-20 column chromatography, and silica gel column chromatography, and the isolated compound was identified to be scopoletin through 1H NMR, 13C NMR, and HPLC–MS. The pot experiments indicated that the treatment of soybean seeds with scopoletin drastically reduced the SCN population. The field experiments performed in 2017 and 2018 revealed that scopoletin decreased over 43.7% juveniles in the roots and over 61.55% cysts in the soil. Scopoletin treatment also promoted soybean growth and improved its yield, with an increase in plot yield by >5.33%. Scopoletin obtained from P. janthinellum Snef1650 could be used as an anti-H. glycines biocontrol agent.