Semi-preparative High-performance Liquid Chromatography Research Articles

Identification and Characterisation of New Vardenafil Analogue Illegally Added to Pressed Candies

The illegal addition of a vardenafil analogue to pressed candies was identified using high-performance liquid chromatography (HPLC). Subsequently, the compound was extracted with acetonitrile under sonication, followed by separation and purification by semi-preparative HPLC. The structure of the compound was determined using high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. The results indicated that the compound was a vardenafil analogue with a molecular formula of C24H34N6O4S. In this compound, the ethoxy group attached to the benzene ring of vardenafil was replaced with a propoxy group. Therefore, the chemical name of this analogue is propoxyphenyl vardenafil. The illegal addition of this compound to functional foods has not been previously reported; therefore, this should be brought to the attention of regulatory authorities, and the compound should be considered in tests for illegal additives in functional and health foods.

Scaling analytical RP-HPLC to semi-preparative for fractionation and characterization of pegfilgrastim oxidized variants.

Scaling analytical RP-HPLC to semi-preparative for fractionation and characterization of pegfilgrastim oxidized variants.

5β-hydroxycostic acid from Laggera alata ameliorates sepsis-associated acute kidney injury through its anti-inflammatory and anti-ferroptosis effects via NF-κB and MAPK pathways.

5β-hydroxycostic acid from Laggera alata ameliorates sepsis-associated acute kidney injury through its anti-inflammatory and anti-ferroptosis effects via NF-κB and MAPK pathways.

A new tetralone glycoside in leaves of Cyclocarya paliurus

The chemical constituents from leaves of Cyclocarya paliurus were isolated and purified by chromatography on silica gel, C_(18) reverse-phase silica gel, and Sephadex LH-20 gel, as well as semi-preparative high-performance liquid chromatography. Six compounds were identified by UV, IR, NMR, MS, calculated ECD, and comparison with literature data as cyclopaloside D(1), boscialin(2),(5R,6S)-6-hydroxy-6-[(E)-3-hydroxybut-1-enyl]-1,1,5-trimethylcyclohexanone(3), 3S,5R-dihydroxy-6R,7-megastigmadien-9-one(4), 3S,5R-dihydroxy-6S,7-megastigmadien-9-one(5), and gingerglycolipid A(6), respectively. Among them, compound 1 was identified as a new tetralone glycoside, and compounds 2-6 were isolated from leaves of C. paliurus for the first time. Furthermore, compound 1 exhibited strong antioxidant activity, with the IC_(50) of(454.20±31.81)μmol·L~(-1) and(881.82±42.31)μmol·L~(-1) in scavenging DPPH and ABTS free radicals, respectively.

Chemical constituents from Alternaria alternata and their activity of down-regulating TMSB10 expression

This study investigated the secondary metabolites in the product of rice fermentation with Alternaria alternata and their activity of down-regulating thymosin beta 10(TMSB10) protein expression. The secondary metabolites of A. alternata were separated and purified by various chromatographic separation techniques, including silica gel column chromatography, Sephadex LH-20 column chromatography, and semi-preparative high-performance liquid chromatography. Their structures were identified by spectral techniques such as nuclear magnetic resonance spectroscopy(NMR), infrared spectroscopy(IR), and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS) and comparison with literature data. A total of 10 compounds were isolated and identified, including two new compounds(1S,3S)-2,3-dihydro-3,6-dihydroxy-8-methoxy-1-methylcyclopenta[c][2]benzopyran-5(1H)-one(1), 3,3a, 6-trihydroxy-8-methoxy-1-methyl-2,3,3a, 9b-tetrahydrocyclopenta[c]isochromen-5(1H)-one(2), and the eight known compounds are alternariol 9-methyl ether(3), 1-deoxyrubralactone(4),(3aR)-3,3a-dihydro-1,6-dihydroxy-8-methoxy-3a-methylcyclopenta[c][2]benzopyran-2,5-dione(5), altechromone A(6), alternariol(7), altenuene(8), altenusin(9), and 3'-hydroxyalternariol 5-O-methyl ether(10). The effects of these compounds on TMSB10 expression were tested. Compound 7 showed a significant down-regulation effect on TMSB10 expression with an inhibition rate of 40.5%. The results showed that benzopyrone compounds of A. alternata have the activity of down-regulating the expression of TMSB10 protein, providing theoretical basis and research value for the study of non-small cell lung cancer.

Cyclobrachycoumarin from Gerbera piloselloides Inhibits Colorectal Cancer In Vitro and In Vivo.

Gerbera piloselloides, a plant in the Asteraceae family, is a traditional Chinese medicinal herb known for its unique therapeutic properties, including reported anti-tumor and antioxidant effects. Recent studies suggest that the main constitute of G. piloselloides, coumarins, may have potential anti-tumor activity. Recent research suggests that coumarins, the active compounds in G. piloselloides, may hold potential anti-tumor activity. However, the pharmacodynamic constituents remain unidentified. This study aims to isolate and characterize the bioactive compounds of G. piloselloides and to assess its anti-tumor effects. Initially, seven compounds, including coumarins, a ketone, and a furanolide, were isolated and identified from G. piloselloides by semi-preparative high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) analysis. The anti-tumor effects of these compounds were evaluated across four different cancer cell lines. Among them, the compound cyclobrachycoumarin showed a significant inhibitory effect on colorectal cancer (CRC) cell proliferation and was selected for further investigation. Cyclobrachycoumarin was found to induce CRC cell apoptosis and cell cycle arrest in a dose-dependent manner. This treatment also led to increased levels of ROS and cleaved PARP, along with decreased expressions of survivin, cyclin D1, and CDK1. In vivo studies further demonstrated that cyclobrachycoumarin effectively reduced tumor growth in HT-29 xenograft models by promoting apoptosis and cell cycle arrest, with a favorable tolerability profile. In summary, this study suggests that cyclobrachycoumarin may be a promising candidate for safe and effective CRC therapy.

Antibacterial Polyketides from the Plant Endophytic Fungus Fusarium sp.

Background: Endophytic fungi have been recognized as new sources of natural products with a variety of biological activities, providing lead compounds for drug discovery and development. Objective: The objective of this study is to isolate and identify the secondary metabolites from the plant endophytic fungus Fusarium sp. HJY2 and evaluate their antibacterial activities. Methods: The compounds were isolated and purified by the methods of silica gel column chromatography, Sephadex LH-20 gel chromatography, and semi-preparative high performance liquid chromatography (HPLC). The structures of the isolated compounds were elucidated by comparing the NMR and MS spectroscopic data with those of pieces of literature. The antibacterial activities were evaluated by the broth microdilution method. Results: Seven polyketides were isolated from the fermented extracts of the fungus Fusarium sp. HJY2 and identified as sydowinol (1), dihydrolateropyrone (2), 13-oxo-9Z,11E-octadecadienoic acid (3), (E)-ferulic acid (4), 4-hydroxyphenylacetic acid (5), methyl 2-(2-hydroxyphenyl)acetate (6) and 4-hydroxy-3-methoxyacetophenone (7). Compound 3 exhibited moderate antibacterial activities against Bacillus subtilis, Mycobacterium smegmatis, Ralstonia solanacearum, and Xanthomonas campestris pv. campestris with MIC values of 40, 40, 80 and 40 μg/mL, respectively. Conclusion: Seven compounds were isolated from the plant endophytic fungus Fusarium sp. HJY2. Compound 1 was isolated from the Fusarium genus for the first time. Compound 3 showed moderate antibacterial activities.

Two new α-carbonylamides from Corydalis Rhizoma

Corydalis Rhizoma is a commonly used traditional Chinese medicine(TCM) for regulating Qi and relieving pain in clinical practice, with remarkable efficacy. However, its pharmacodynamic substances are not yet fully understood and require further research. In this study, 24 compounds were isolated and identified from the aqueous extracts of vinegar-processed Corydalis Rhizoma using techniques such as macroporous adsorption resin column chromatography, Sephadex LH-20 column chromatography, and semi-preparative high-performance liquid chromatography. Their structures were determined based on their physicochemical properties and spectroscopic methods, including UV, IR, HR-MS, 1D NMR, and 2D NMR. Among these, compounds 1 and 2 are two rare natural α-carbonamide alkaloids, named yanhuoxamide A(compound 1) and yanhuoxamide B(compound 2), respectively. Compounds 3-24 are known compounds, identified as xanthoplanine(3), stigmast-4-ene-3,6-dione(4), norchelerythrine(5), ethyl ferulate(6), 6-hydroxymethyl-3-pyridinol(7), 6-(\[1,3\]dioxolo\[4,5-g\]isoquinoline-5-carbonyl)-2,3-dimethoxy-benzoic acid methyl ester(8), 1H-indole-3-carbaldehyde(9), 4-hydroxy-3-methoxy ethyl cinnamate(10), berberal(11), oblongine trifluoroacetate(12), thalbaicalidine(13), cyclopiamide(14), nicotinamide(15), dehydrocorypalline trifluoroacetate(16), 6-acetonyldihydrochelerythrine(17), 6-acetonyldihydrosanguinarine(18), norsanguinarine(19), oxysanguinarine(20), bulbocapnine(21), corydine(22),(-)-(13aS)-stylopine(23), and(-)-(9S,13S)-pallidine(24). Among these, compounds 3-15 were isolated from the genus Corydalis for the first time, and compounds 16-24 were isolated from Corydalis Rhizoma for the first time. Additionally, the inhibitory activity of compounds 1 and 2 on acetylcholinesterase(AChE) was evaluated.

Assessment of loliolide extracted from Biserula pelecinus, present during in vitro oocyte maturation, on fertilisation and embryo development in sheep

Context As a ‘duty of care’, it is important to test whether new forage plants for ruminants contain secondary compounds (PSCs) that affect reproductive performance. We have previously observed, a posteriori, that the presence of a methanolic extract of Biserrula pelecinus during maturation of sheep oocytes increased fertilisation rate and blastocyst development. This result needed to be verified a priori and, if the outcome was repeated, we needed to identify the plant secondary metabolite responsible. Aims To test whether PSCs from B. pelecinus, when added to the oocyte maturation medium, improve fertilisation rate and blastocyst development; to test whether loliolide is the active molecule produced by B. pelecinus. Methods Methanol–chloroform extracts of B. pelecinus were fractionated using rapid silica filtration and solvents of increasing polarity. Fractions at final concentrations of 0, 100 or 200 μg mL−1 were added to the medium used to mature sheep cumulus–oocyte complexes (COCs) and effects were determined for maturation, subsequent cleavage rate, blastocyst rate, hatching rate, blastocyst efficiency and total blastocyst cell number (TCN). Results Fraction BP-6 at 100 μg mL−1 reduced blastocyst rate (P < 0.05), but had no effect when the dose was doubled to 200 μg mL−1. Further fractionation using semi-preparative high-performance liquid chromatography showed loliolide as the most abundant compound in BP-6. Supplementation of the in vitro maturation medium with loliolide (0, 2.5, 5, 10 and 25 μg mL−1) did not affect any measure of embryo development. All COCs treated with B. pelecinus fractions reached the final stage of embryo development, blastocyst hatching. Total blastocyst cell number was not affected. Conclusion The presence of fractions of B. pelecinus extract during in vitro oocyte maturation can reduce embryo development. Implications In vitro techniques can detect potential effects of forages on reproduction. Some fractions from an extract of B. pelecinus when present during oocyte maturation can reduce embryo development. The abundant PSC, loliolide, was not responsible. There was no indication that a PSC in B. pelecinus improves outcomes.

Exploring novel antioxidant cyclic peptides in corn protein hydrolysate: Preparation, identification and molecular docking analysis

Exploring novel antioxidant cyclic peptides in corn protein hydrolysate: Preparation, identification and molecular docking analysis

Evaluation of Echinacea purpurea Extracts as Immunostimulants: Impact on Macrophage Activation.

Echinacea purpurea has been traditionally used to strengthen the immune system. Therefore, herein, we investigated the potential of E. purpurea aqueous extracts (AEs) obtained from flowers (F), leaves (L), or roots (R) as an immune booster in human primary monocyte-derived macrophages (hMDMs). Additionally, to identify the main class of compounds (phenolic/carboxylic acids vs. alkylamides) responsible for the bioactivity, the three AEs were fractioned by semi-preparative high-performance liquid chromatography (HPLC). The AEs and the isolated phenolic/carboxylic acidic fractions were not cytotoxic for hMDMs for all tested concentrations, as confirmed by the metabolic activity and DNA content assays. Moreover, AE drastically induced the production of the interleukin (IL)-6 and tumor necrosis factor (TNF)-α, with a minimal effect on IL-1β and prostaglandin E2 (PGE2), supporting their potential for macrophage activation. Interestingly, in the presence of the phenolic/carboxylic acidic fractions, this efficacy considerably decreased, suggesting a complementary effect between compounds. AE also triggered the phosphorylation of the extracellular signal-regulated kinase (ERK) 1/2 and p38 signaling pathways and upregulated the cyclooxygenase (COX)-2 expression in hMDMs. Overall, AE-F was demonstrated to be the most powerful immunostimulant extract that can be related to their higher number in identified bioactive compounds compared to AE-L and AE-R. These results highlight the efficiency of E. purpurea AE to enhance the function of a key cell type of the immune system and their potential as immunostimulant formulations for patients with a compromised immune system due to certain diseases (e.g., acquired immunodeficiencies) and treatments (e.g., chemotherapy).

A new flavan-3-ol from Sargentodoxae Caulis

Sargentodoxae Caulis was extracted with 80% ethanol and separated by macroporous resin, MCI, and ODS column chromatography and semi-preparative high performance liquid chromatography. The structures of the compounds were identified based on the NMR and MS data. A total of 19 compounds were identified as parabaroside D(1),(R)-2-(3,4-dihydroxyphenyl)-2-hydroxyethyl-O-β-D-glucopyranoside(2),(S)-2-(3,4-dihydroxyphenyl)-2-hydroxyethyl-O-β-D-glucopyranoside(3), protocatechin-3-O-β-D-glucoside(4), p-hydroxybenzoate-β-D-glucopyranoside(5), gentisic-5-O-β-D-glucopyranoside(6), vanillic acid 4-O-β-D-glucoside(7), syringic acid glucoside(8), uracil(9), uridine(10), neochlorogenic acid(11), chlorogenic acid(12), cryptochlorogenic acid(13), 3,4-dihydroxyphenylethanol glucoside(14), cuneataside A(15), cuneataside C(16), 4-hydroxy-3-methoxyacetophenone-4-O-β-D-apiose-(1→6)-β-D-glucopyranoside(17), proanthocyanidin B2(18), and baimantuoluoamide B(19). Compound 1 was a new flavan-3-ol, and compounds 2, 3, 5, 6, 9, and 19 were isolated from this plant for the first time. Compounds 2 and 3 were a pair of epimers. Compound 14 had the highest anti-inflammatory activity.

Relay PHOS: Ligands with Fluxional Chirality in Asymmetric Palladium-Catalyzed Allylic Alkylation.

A modular route toward the synthesis of P,N ligands containing a fluxional group along the pyrazoline ring core is described. The racemic ligands were accessed in three steps from commercially available fluoroacetophenone in overall yields ranging from 18 to 76%. The enantiopure ligands were obtained using semi-preparative chiral high-performance liquid chromatography and chiral enantioselective phase-transfer catalysis. The effectiveness of the new ligands was assessed in palladium-catalyzed allylic alkylation with diphenylpropenyl acetate and dimethylpropenyl acetate. Under optimized conditions, diphenylpropenyl acetate underwent alkylation with dimethyl malonate in 98% yield and 94% ee. In general, the enantioselectivity for the product correlates with the size of the ligand fluxional group; the larger the fluxional group, the higher the selectivity.

In vitro analysis of quercetin-like compounds from mistletoe Dendrophthoe pentandra (L.) Miq as a potential antiviral agent for Newcastle disease

Background Recent evidence suggests that some flavonoid compounds obtained from crude methanol extract of mistletoe leaves (Dendrophthoe pentandra L. Miq), also known as Benalu Duku (BD), have antimicrobial effects. Thus, the plant has the potential to eliminate viruses that may cause outbreaks in chicken farms. This study aimed to prove the in vitro ability of flavonoid compounds, namely quercetin-like compounds (QLCs), to eliminate field viruses, specifically the Newcastle disease virus (NDV). Methods This research was performed in two stages. An in vitro test was used with a post-test of the control groups designed at a significance of 0.05. BD leaves (5 kg) were extracted using a maceration method with methanol and then separated into hexane, chloroform, ethyl acetate, and methanol fractions. The final extracted products were separated using semi-preparative high-performance liquid chromatography (HPLC) to obtain QLCs. The QLCs were identified and compared with quercetin using HPLC, proton and carbon nuclear magnetic resonance spectrometry, Fourier transform infrared spectrophotometry and ultra-performance liquid chromatography-mass spectrometry. The activity of QLCs was tested in vitro against the NDV at a virulence titter of 10−5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. Results Solutions of 0.05% (w/v) QLCs were discovered to have antiviral activity against NDVs, with an average cytopathogenic effect antigenicity at a 10−5 dilution (p<0.05). Conclusions QLCs from flavonoids from the leaves of BD have in vitro antiviral bioactivity against NDV at a virulence titter of 10-5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. QLCs may have the potential to be developed as medicinal compounds for the treatment of other human or animal viral infections.

In vitro analysis of quercetin-like compounds from mistletoe Dendrophthoe pentandra (L.) Miq as a potential antiviral agent for Newcastle disease

Background Recent evidence suggests that some flavonoid compounds obtained from crude methanol extract of mistletoe leaves (Dendrophthoe pentandra L. Miq), also known as Benalu Duku (BD), have antimicrobial effects. Thus, the plant has the potential to eliminate viruses that may cause outbreaks in chicken farms. This study aimed to prove the in vitro ability of flavonoid compounds, namely quercetin-like compounds (QLCs), to eliminate field viruses, specifically the Newcastle disease virus (NDV). Methods This research was performed in two stages. An in vitro test was used with a post-test of the control groups designed at a significance of 0.05. BD leaves (5 kg) were extracted using a maceration method with methanol and then separated into hexane, chloroform, ethyl acetate, and methanol fractions. The final extracted products were separated using semi-preparative high-performance liquid chromatography (HPLC) to obtain QLCs. The QLCs were identified and compared with quercetin using HPLC, proton and carbon nuclear magnetic resonance spectrometry, Fourier transform infrared spectrophotometry and ultra-performance liquid chromatography-mass spectrometry. The activity of QLCs was tested in vitro against the NDV at a virulence titter of 10−5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. Results Solutions of 0.05% (w/v) QLCs were discovered to have antiviral activity against NDVs, with an average cytopathogenic effect antigenicity at a 10−5 dilution (p<0.05). Conclusions QLCs from flavonoids from the leaves of BD have in vitro antiviral bioactivity against NDV at a virulence titter of 10-5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. QLCs may have the potential to be developed as medicinal compounds for the treatment of other human or animal viral infections.

Two new pinophol derivatives from endophytic fungus Penicillium herquei JX4 hosted in Ceriops tagal

An OSMAC strategy was used to study secondary metabolites and anti-inflammatory activities of the endophytic fungus Penicillium herquei JX4 hosted in Ceriops tagal. The PDB ferment of fungus P. herquei JX4 was isolated, purified, and identified by using silica gel column chromatography, gel column chromatography, octadecylsilyl(ODS) column chromatography, and semi-preparative high-performance liquid chromatography. Two new pinophol derivatives, pinophol H(1) and pinophol I(2) were isolated and identified, and they were evaluated in terms of the inhibitory activities against the nitric oxide(NO) production induced by lipopolysaccharide(LPS) in mouse macrophage RAW264.7 cells. The results showed that compound 1 had significant inhibitory activity on NO production, with an IC_(50) value of 8.12 μmol·L~(-1).

In vitro analysis of quercetin-like compounds from mistletoe Dendrophthoe pentandra (L.) Miq as a potential antiviral agent for Newcastle disease

Background Recent evidence suggests that some flavonoid compounds obtained from crude methanol extract of mistletoe leaves (Dendrophthoe pentandra L. Miq), also known as Benalu Duku (BD), have antimicrobial effects. Thus, the plant has the potential to eliminate viruses that may cause outbreaks in chicken farms. This study aimed to prove the in vitro ability of flavonoid compounds, namely quercetin-like compounds (QLCs), to eliminate field viruses, specifically the Newcastle disease virus (NDV). Methods This research was performed in two stages. An in vitro test was used with a post-test of the control groups designed at a significance of 0.05. BD leaves (5 kg) were extracted using a maceration method with methanol and then separated into hexane, chloroform, ethyl acetate, and methanol fractions. The final extracted products were separated using semi-preparative high-performance liquid chromatography (HPLC) to obtain QLCs. The QLCs were identified and compared with quercetin using HPLC, proton and carbon nuclear magnetic resonance spectrometry, Fourier transform infrared spectrophotometry and ultra-performance liquid chromatography-mass spectrometry. The activity of QLCs was tested in vitro against the NDV at a virulence titter of 10−5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. Results Solutions of 0.05% (w/v) QLCs were discovered to have antiviral activity against NDVs, with an average cytopathogenic effect antigenicity at a 10−5 dilution (p<0.05). Conclusions QLCs from flavonoids from the leaves of BD have in vitro antiviral bioactivity against NDV at a virulence titter of 10-5 Tissue Culture Infectious Dose 50% (TCID50) in chicken kidney cell culture. QLCs may have the potential to be developed as medicinal compounds for the treatment of other human or animal viral infections.

Chiral Hydroxy Metabolite of Mebendazole: Analytical and Semi-Preparative High-Performance Liquid Chromatography Resolution and Chiroptical Properties.

Mebendazole (MBZ) is a benzimidazole carbamate anthelmintic used worldwide for the treatment and prevention of parasitic disorders in animals and humans. A large number of in vivo and in vitro studies have demonstrated that MBZ also has anticancer activity in multiple types of cancers. After oral administration, the phenylketone moiety of MBZ is rapidly reduced to the hydroxyl group to form the chiral hydroxy metabolite (MBZ-OH). To the best of our knowledge, there is no information in the literature on the stereochemical course of transformation and the anthelmintic and antitumor activity of individual enantiomers of MBZ-OH. In the present study, we describe in detail the direct HPLC resolution of MBZ-OH on a 100 mm × 4.6 mm Chirapak IG-3 column packed with 3 μm silica particles containing amylose (3-chloro-5-methylphenylcarbamate) as a selector. At 25 °C and using pure methanol as the mobile phase, the enantioseparation and resolution factors were 2.38 and 6.13, respectively. These conditions were scaled up at a semi-preparative scale using a 250 mm × 10 mm Chiralpak IG column to isolate multi-milligram amounts of both enantiomeric forms of the chiral metabolite. The chiroptical properties of the collected enantiomers were determined and, through a theoretical study, were related to the more stable conformations of MBZ-OH. The first and second eluted enantiomers were dextrorotatory and levorotatory, respectively, in dimethylformamide solution. Finally, by recording the retention factors of the enantiomers as the water content in the water-acetonitrile mobile phases was progressively varied, U-shaped retention maps were generated, indicating a dual and competitive hydrophilic interaction liquid chromatography and reversed-phase liquid chromatography retention mechanism on the Chirapak IG-3 chiral stationary phase.

Secondary Metabolites from the Mangrove-derived Fungus Trichoderma sp.

Background:: Secondary metabolites from the mangrove-derived fungi have great potential to produce natural products with novel structures and significant biological activities. Objective:: The objective of this study was to isolate and identify the secondary metabolites from the mangrove-derived fungus Trichoderma sp. WHUF0342, and evaluate their antibacterial activities. Methods:: The compounds were isolated and purified by silica gel column chromatography, Sephadex LH-20 gel chromatography, and semi-preparative high-performance liquid chromatography (HPLC). Their structures were elucidated by comparing the NMR and MS spectroscopic data with those of literature. The antibacterial activity were evaluated by modified broth microdilution assay. Results:: Eight compounds were isolated from the fermented extracts of the fungus Trichoderma sp. WHUF0342 and identified as chaxine B (1), nafuredin (2), dichlorodiaportin (3), ferulaic acid (4), bis(2-ethylhexyl) benzene-1,2-dicarboxylate (5), methyl 4-hydroxyphenylacetate (6), 4- hydroxyphenyl acetate (7), and 4-hydroxyphenylethyl acetate (8). Chaxine B (1) showed antibacterial activity against the phytopathogenic bacterium Ralstonia solanacearum with a minimum inhibitory concentration (MIC) value of 16 μg/mL. The antibacterial activity against plant pathogen of compound 1 was reported for the first time in this study. Conclusion:: This study not only enriched the secondary metabolites of mangrove-derived fungi but also provided a valuable resource for the prevention of agricultural pathogen infections.

Identification of major degradation products of Clorsulon drug substance including its degradation pathways by high resolution mass spectrometry and NMR

Identification of major degradation products of Clorsulon drug substance including its degradation pathways by high resolution mass spectrometry and NMR