Sephadex LH-20 Column Chromatography Research Articles

Two new phenolic amides from Allium chinense

ObjectiveTo isolate the phenolic amides from the dried bulbs of Allium chinense and investigate their myocardium protective activities. MethodsThe chemical constituents were isolated and purified by combining with silica gel column, Sephadex LH-20 column, HPLC and other chromatography techniques. Their structures were elucidated by NMR techniques and mass spectrometry. The isolated compounds were evaluated to determine their protective effect for myocardium cells in vitro. ResultsTwo new phenolic amides, namely, alichinemide I (1) and alichinemide II (2), and six konwn amides were isolated from the dried bulbs of A. chinense. The structures of compounds 3–8 were identified as 3-indolcarbaldehyde (3), 1-(2-aminophenyl)urea (4), 2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole-3-carboxylic acid (5), N-trans-feruloyltyramine (6), N-trans-p-coumaroyltyramine (7), and N-(3,4-dimethoxyphenethyl) acetamide (8). Compound 3 (50 μmol/L) showed significant inhibitory effect on the damage of H9c2 myocardial cells induced by H2O2in vitro. ConclusionCompounds 1 and 2 were new phenolic amides. Compound 3 could be one of the potential myocardium protective constituents of A. chinense.

Bio-Fabrication of ZnONPs from Alkalescent Nucleoside Antibiotic to Control Rice Blast: Impact on Pathogen (Magnaporthe grisea) and Host (Rice).

In the traditional method of the bio-fabrication of zinc oxide nanoparticles (ZnONPs), bacterial strains face metal toxicity and antimicrobial action. In the current study, an alkalescent nucleoside antibiotic was mixed with zinc hexanitrate to fabricate the ZnONPs. An integrated approach of DIAION HP-20 macroporous resin and sephadex LH-20 column chromatography was adopted to separate and purify alkalescent nucleoside AN03 from Streptomyces koyanogensis. Alkalescent nucleoside was confirmed by the Doskochilova solvent system. The bio-fabricated ZnONPs were characterized by using Fourier transform infrared (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) analyses. The XRD spectrum and the TEM images confirmed the crystallinity and the spherical shape of the ZnONPs with an average size of 22 nm. FTIR analysis showed the presence of functional groups, which confirmed the bio-fabrication of ZnONPs from alkalescent nucleoside ANO3. In-vitro studies showed that 75 μg/mL of ZnONPs had a strong inhibitory zone (28.39 mm) against the Magnaporthe grisea and significantly suppressed the spore germination. SEM and TEM observations respectively revealed that ZnONPs caused breakage in hyphae and could damage the cells of M. grisea. Greenhouse experiments revealed that the foliar spray of ZnONPs could control the rice blast disease by 98%. Results also revealed that ZnONPs had positive effects on the growth of the rice plant. The present study suggested that ZnONPs could be fabricated from microbe-derived nucleoside antibiotics without facing the problems of metal toxicity and antimicrobial action, thus overcoming the problem of pathogen resistance. This could be a potent biocontrol agent in rice blast disease management.

A new bibenzyl derivative from stems of Dendrobium officinale

Eleven compounds were isolated from the 95% ethanol extract of the stems of Dendrobium officinale after water extraction by various modern chromatographic techniques, such as silica gel column chromatography(CC), octadecyl-silica(ODS) CC, Sephadex LH-20 CC, preparative thin layer chromatography(PTLC) and preparative high performance liquid chromatography(PHPLC). According to spectroscopic analyses(MS, 1D-NMR, 2D-NMR) combined with optical rotation data and calculated electronic circular dichroism(ECD), their structures were identified as dendrocandin Y(1), 4,4'-dihydroxybibenzyl(2), 3-hydroxy-4',5-dimethoxybibenzyl(3), 3,3'-dihydroxy-5-methoxybibenzyl(4), 3-hydroxy-3',4',5-trimethoxybibenzyl(5), crepidatin(6), alternariol(7), 4-hydroxy-3-methoxypropiophenone(8), 3-hydroxy-4,5-dimethoxypropiophenone(9), auriculatum A(10) and hyperalcohol(11). Among them, compound 1 was a new bibenzyl derivative; compounds 2 and 7-11 have not been previously reported from Dendrobium plants; compound 6 was reported from D.officinale for the first time. Compounds 3-6 exhibited potent antioxidant activity with IC_(50) values of 3.11-9.05 μmol·L~(-1) in ABTS radical scavenging assay. Compound 4 showed significant inhibitory effect on α-glucosidase, with IC_(50) value of 17.42 μmol·L~(-1), indicating that it boasted hypoglycemic activity.

Two-step isolation of the two major paraconic acids of Cetraria islandica.

The lichen Cetraria islandica is traditionally used as a demulcent for the symptomatic treatment of irritations of the mouth and throat and associated dry cough, as well as for the treatment of temporary loss of appetite. In addition to depsides and depsidones, thalli contain paraconic acids, a group of secondary metabolites commonly found in lichens and fungi. Among those, protolichesterinic acid has shown promising pharmacological activities. However, the efficient isolation of paraconic acids is quite complex due to their very similar chemical structures and their weak ultraviolet absorption. In the present work, a two-step isolation protocol of protolichesterinic acid and lichesterinic acid from a complex paraconic acid mixture is described using Sephadex LH20 column chromatography and fast centrifugal partition chromatography. Final purities higher than 95% and recoveries above 50% are achieved. Additionally, reliable qualitative techniques for detecting and differentiating paraconic acids are described. Finally, some data on compound stability and enantiomeric purity are shown.

Evaluating the phenolic composition and antioxidant properties of Georgia pecans after in vitro digestion

Acetonic crude extracts from raw and roasted Georgia pecans were prepared and subjected to in vitro gastrointestinal digestion. Digested and undigested extracts of raw pecan phenolics were then separated into low- and high-molecular-weight (LMW and HMW) fractions via Sephadex LH-20 column chromatography; afterwards, they were characterized by RP-HPLC-ESI-MS. The LMW fraction consisted primarily of flavan-3-ols and ellagic acid derivatives and following digestion there was an overall loss in phenolics from 16% to 100%. In the HMW fraction, procyanidins with degrees of polymerization ranging from dimers to hexamers were present. Following digestion, a loss in higher oligomeric procyanidins was observed, along with a significant increase in quantity of dimers. This increase was attributed to the dimerization of (+)-catechin/(−)-epicatechin and the scission of larger procyanidins, mainly tetramers to hexamers. The loss of phenolics following digestion, as seen by HPLC characterization, was reflected in reduced total phenolics content and antioxidant capacity, as determined by selected in vitro antioxidant assays.

Response surface methodology-optimized extraction of flavonoids from pomelo peels and isolation of naringin with antioxidant activities by Sephadex LH20 gel chromatography

In this study, flavonoids were extracted from pomelo peels and naringin was isolated from the flavonoid extract. The effects of extraction parameters, namely, ethanol concentration, solid-to-liquid ratio, and extraction time, on the yield of flavonoids extracted from pomelo peels were analyzed according to the Box-Behnken design of response surface methodology. The experimental conditions for flavonoid extraction were optimized, and naringin was separated from the extracted flavonoids using Sephadex LH-20 column chromatography. Experimental results showed that the influence of factors on the extraction rate of flavonoids from pomelo peels was in the order of ethanol concentration > solid-to-liquid ratio > extraction time, and the optimal extraction parameters were 85% ethanol concentration, 1:20 solid-to-liquid ratio, and 4-h extraction time for extracting flavonoids from pomelo peels. Under these conditions, the yield of flavonoids was 6.07 ± 0.06 mg/g. After three times of extraction, the flavonoid extraction rate reached 96.55%, and the residual naringin in the pomelo peels was 0.017 mg/g, at which point the bitterness in the pomelo peels disappeared. Two components, namely, PF1 and PF2, were separated from the crude flavonoid of pomelo peels through Sephadex LH20 column chromatography. PF2 was identified as naringin by high-performance liquid chromatography tandem mass spectrometry, with a purity of 95.7 ± 0.23%. Both flavonoids and PF2 exhibited good in vitro radicals scavenging activities on DPPH, ABTS, superoxide anion and hydroxyl.

The Chemical Composition and Antidiabetic, Neuroprotective and Cytotoxic Activities of Soft Hulls (Mesocarp) of Pistachio (Pistacia vera) Fruits

Pistachio (Pistacia vera L.) is an important cultivated plant in the Southeastern Anatolia region and its fruits are widely used in the food industry. The previous studies mostly focused on the food minerals and components. However, there is no study on chemical components and biological activity of the soft hulls of the pistachio fruits. In this study, it was focused on the acetone and water extracts of the soft hulls of pistachio fruits. Hence, the acetone extract was subjected to sephadex LH-20 column chromatography and fractioned into five fractions (Frs. A-E) according to molecular weight of components. A triterpen compound isolated from the Fr. B by crystallation method and its chemical structure was characterized as masticadienonic acid by spectroscopic methods. The fractions contain a mixture of the anacardic acids 13:1, 15:2, 15:1 and 17:1 and their derivatives according to their spectroscopic data and GC-MS analysis. Shikimic acid used in the synthesis of the oseltamivir, antiviral agent was also purified at high yield (14.36%) from the water extract of the soft hulls of pistachio fruits. In order to explore the antidiabetic properties of the pure compounds, the extracts and the fractions, their inhibition effects were determined on the activities of digestive enzymes (α-glucosidase and α-amylase). All of the extracts, masticadienonic acid and the fractions containing the anacardic acids strongly inhibited the α-glucosidase activity much more than acarbose. However, all applications exhibited much weaker inhibitory properties againts α-amylase, as compaired to the inhibition effect of the acarbose. Furthermore, the treatments of mesocarps of Pistachio fruits acted as much weaker inhibitors against AChE, whereas the acetone extract and its fractions containing different rates of anacardic acids were powerful agents against BChE as strong as neostigmine and galantamine. The cytotoxic activities of the extracts and the compounds against HUVEC, A549 and H1299 cells were also determined using the MTT analysis method and it was determined that the acetone extract and the compounds, masticadienonic and shikimic acids showed cytotoxic effects on the cells

Chemical Components of the Fruits of Kigelia africana and their DPPH, Intracellular ROS, and Tyrosinase Inhibitory and Apoptotic Effects

The present study was performed to identify the major chemical constituents in the fruits of Kigelia Africana. Six chemicals were isolated by silica gel and Sephadex LH-20 column chromatography and identified by ESI-MS and 1D-NMR as β-sitosterol (1), ferulic acid (2), caffeic acid (3), gallic acid (4), luteolin (5), and luteolin-7-O-β-D-glycopyranoside (6). Compounds 3 and 4 exhibited DPPH (1,1-diphenyl-2-picrylhydrazyl radical) free radical scavenging activity with IC50 values of 19.17 ± 1.01 and 10.24 ± 0.18 μM, respectively. Compound 4 had a moderate antioxidant effect with an IC50 value of 29.17 ± 1.64 μM versus DCHF-DA (dichloro-dihydro-fluorescein diacetate)-induced intracellular ROS generation. Compound 3 inhibited mushroom tyrosinase with an IC50 value of 39.91 ± 1.82 μM, and compound 5 dose-dependently induced the apoptosis of HCT116 human colorectal cancer cells.

Purification, characterization and structural identification of a novel bacteriocin produced by marine original Enterococcus durans YQ-6, and its inhibition of Listeria monocytogenes

The bacteriocin CAMT6 is a novel bacteriocin produced by Enterococcus durans YQ-6 isolated from Larimichthys polyactis in the South China Sea. In this study, the bacteriocin CAMT6 was purified by extraction using ethyl acetate, Sephadex LH-20 column chromatography, cation exchange chromatography and reversed-phase high-performance liquid chromatography, in sequence. The Liquid Chromatograph Triple Quadrupole Mass Spectrometer (LC-MS/MS) analysis revealed that the relative molecular mass and amino acid sequence of the bacteriocin CAMT6 were 1254.63 Da and N-GAVHDVKDVLDS, respectively. Combined with the circular dichroism (CD) spectroscopy results, CAMT6 was determined to be a novel Class IId bacteriocin. CAMT6 exhibited broad-spectrum antibacterial activity, inhibiting both gram-negative and gram-positive bacteria, even fungi. CAMT6 exhibited strong temperature stability, was stable over pH 2–7, and was inactivated by proteases. CAMT6 also significantly removed L. monocytogenes biofilms and inhibited L. monocytogenes by disrupting the permeability of the cell membrane. Furthermore, CAMT6 can effectively inhibit the growth of L. monocytogenes in chicken breast. These results suggest that the bacteriocin CAMT6 could serve as a potential biological preservative for food.

Nematicidal Metabolites from the Actinomycete Micromonospora sp. WH06.

A nematicidal actinomycete strain WH06 was isolated from soil samples and was identified using 16S rRNA as Micromonospora sp. Through medium screening and fermentation, 10 metabolites were isolated from the ethyl acetate extract of its fermentation broth using Sephadex LH-20 and silica gel column chromatography. These compounds were identified as N-acetyltyramine (1), N-acetyltryptamine (2), 1-methylhydantoin (3), benzenepropanoic acid (4), cyclo-(L-Pro-L-Tyr) (5), cyclo(L-Phe-Gly) (6), catechol (7), methyl (4-hydroxyphenyl)acetate (8), 3-hydroxybenzoic acid (9), and 4-hydroxybenzoic acid (10). In an in vitro assay against Meloidogyne incognita, a root-knot nematode, compounds 1, 4, 9, and 10 show nematicidal activity. Among them, benzenepropanoic acid (4) causes 99.02% mortality of nematode at 200 μg mL-1 after 72 h. Moreover, compound 4 also displays activity in inhibiting egg hatching of M. incognita. This suggests that Micromonospora sp. WH06 is a promising candidate for biocontrol of M. incognita.

P-Terphenyl glucosides from the culture broth of Phlebiopsis castanea.

A new p-terphenyl derivative, hydroxystrepantibin D (1), was isolated along with two known p-terphenyls (2 and 3) from the culture broth of Phlebiopsis castanea. These compounds were isolated using silica gel column chromatography, reversed-phase medium-pressure liquid chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. Their structures were determined based on spectroscopic methods. These compounds exhibited free radical scavenging activities with IC50 values in the range from 22.2 to 158.4 μM against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical and in the range from 161.1 to 356.1 μM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical.

One new triterpenoids from Momordica charantia L

Momordica charantia L. (M. charantia) is an annual climbing herb in Cucurbitaceae. It is not only a food, but also a drug with a long history of application. This study aims to isolate and identify the chemical constituents form M. charantia and evaluate their inhibiting effect on Hcy-induced proliferation of VSMCs. Silica column chromatography, ODS silica column chromatography, Sephadex LH-20 column chromatography and semi-preparative HPLC were used to obtain one new compound (1). The inhibition on Hcy-induced proliferation of VSMCs 1 was tested through MTT method. As a result, 1 could partially rescue Hcy-induced proliferation of VSMCs at both 5 and 25 μM.

Cytotoxic lanostane-type triterpenes from the fruiting bodies of Ganoderma lucidum

A new lanostane-type triterpene, namely 3-oxo-5α-lanosta-7,9(11)-dien-24-oic acid methyl ester (2), and three known compounds including ganoderal A (1), ganoderiol B (3) and ganodermenonol (4) were isolated from the fruiting bodies of Ganoderma lucidum by silica gel column chromatography and Sephadex LH-20 column chromatography. Their structures were determined by extensive NMR data and mass spectral analysis. The in vitro cytotoxic activity of the isolated compounds against SK-Hep-1, HepG2, Hela and Hela/VCR cancer cell lines was assessed by using MTT assay. The IC50 values of compound 1 were 43.09 ± 2.86, 42.31 ± 1.78 and 46.51 ± 1.95 μM in SK-Hep-1, HepG2 and Hela cells, respectively, after 48 h. The IC50 values of compound 4 were 44.70 ± 2.32 and 41.33 ± 2.15 μM in Hela and Hela/VCR cells, respectively, after 48 h.

Isolation and Identification of Secondary Metabolites Produced by Phytopathogenic Fungus Corynespora cassiicola from Hevea brasiliensis

The secondary metabolites of the phytopathogenic fungus Corynespora cassiicola CC01 from Hevea brasiliensis were investigated. As a result, two new compounds, 5-acetyl-7-hydroxy-6- methoxybenzofuran-2(3H)-one (1) and (S)-2-(2,3-dihydrofuro [3,2-c]pyridin-2-yl)propan-2-ol (2), together with seven known compounds, 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (3), 3,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (4), curvulin acid (5), 2-methyl-5-carboxymethyl- 7-hydroxychromone (6), tyrosol (7), p-hydroxybenzoic acid (8) and cerevisterol (9), were isolated from the fermentation extract by comprehensive silica gel, reverse phase silica gel, Sephadex-LH20 column chromatography and high-performance liquid chromatography (HPLC). The structures of these compounds were identified by using high-resolution electrospray mass spectrometry (HRESIMS), nuclear magnetic resonance spectroscopy (NMR), optical rotation, ultraviolet and infrared spectroscopy techniques and a comparison of NMR data with those reported in the literature. Compounds 1 and 2 were new compounds, and compounds 3-9 were discovered from this phytopathogenic fungus for the first time. Compounds 1-9 were tested for phytotoxicity against the fresh tender leaf of Hevea brasiliensis, and the results show that none of them were phytotoxic. Additionally, these compounds were subjected to an antimicrobial assay against three bacteria (E. coli, methicillin-resistant Staphylococcus aureus and Micrococcus luteus), but they showed no activity.

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.