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Flavonoid glycoside degradation can proceed through two alternative enzymatic pathways: one that is mediated by monoglycosidases, and the other catalyzed by a diglycosidase. β-Diglycosidase performs the flavonoid deglycosylation in a single reaction. The characterized β-diglycosidase activities recognize the following disaccharidic sugar moieties: β-primeverose, acuminose, vicianose, and β-rutinose. The present paper reviews the biochemical characteristics and potential industrial applications of microbial β-diglycosidases that break down plant diglycoconjugated flavonoids.

A new pyrrocidine A derivative, 19-epi-pyrrocidine A (1) was isolated from the insect–derived fungus Neonectria ramulariae In-2, together with known pyrrocidine A (2). The structure of 1 was determined by extensive 1D- and 2D-NMR, and MS spectral analyses. The absolute configuration of 2 was confirmed for the first time by X-ray crystallography. Compound 1 exhibited cytotoxicity against human acute promyelocytic leukemia HL60 cells (IC50 2.05 μM). In addition, semi-synthetic compounds 19-O-methyl-pyrrocidine A (3), 19-O-acetyl-pyrrocidine A (4), and 1,2-4,5-17,18-triepoxy-pyrrocidine A (5) were found to possess significant cytotoxicity, with IC50 values of 0.66 μM, 0.19 μM, and 2.00 μM, respectively.

Six flavonoid compounds, kaempferol (1), quercetin (2), acacetin (3), quercetin-3- O - β -D-glucopyranoside (4), kaempferol-3- O - β -D-glucopyranoside (5), and isorhamnetin-3- O - β -D-glucopyranoside (6), were isolated from the methanol extract of the Lygodium microphyllum herb. The chemical structures of compounds 1-6 were identified on the basis of spectroscopic evidence and comparison with previously reported spectral data. Compounds 1-6 were isolated for first time from this plant. Their antioxidant activity against DPPH (2,2-Diphenyl-1-picrylhydrazyl) was evaluated. Among the compounds, quercetin (2) showed high antioxidant activity with IC 50 values of 6.94 ± 0.03 μ g/mL.

Two dammarane-type triterpenoids, 20 S ,24 S -epoxy-3α,25-dihydroxydammarane ( 1 ) and 3α-acetyl-20 S ,24 S -epoxy-3α,25-dihydroxydammarane ( 2 ), have been isolated from the stembark of Aglaia argentea . The chemical structure of compounds ( 1 and 2 ) were identified by spectroscopic evidences including UV, IR, 1D-NMR, 2D-NMR and MS as well as by comparing with previously reported spectral data. Those compounds were isolated from this plant for first time. Compounds ( 1 and 2 ) showed cytotoxic activity against P-388 murine leukemia cells with IC 50 values of 23.96 and 8.14 mM, respectively. DOI: http://dx.doi.org/10.15408/jkv.v4i1.7065

Three previously undescribed oleanane-type saponins acylated with monoterpenic acid, kamerunosides A, B, and C were isolated from the stem liana of Acacia kamerunensis . Their structures were elucidated on the basis of extensive 1D and 2D NMR data and HRESIMS analyses. Their cytotoxicities were evaluated against HL60 cells. Kamerunoside B was the most cytotoxic.

Basella alba is a perennial plant of the Basellaceae and is known by various common names including Malabar spinach. There are few insects that cause damage to B. alba. In this study, we examined the effect of B. alba leaves on the growth of Spodoptera litura larvae. B. alba leaves and a methanolic extract of the leaves inhibited the growth of S. litura larvae. Half of the larvae reared on the leaves died within 1 week. We found that two flavonoids, vitexin, and vitexin-2″-O-arabinofuranoside, were abundant in the methanol extract of leaves. When larvae were reared on purified vitexin or vitexin-2″-O-arabinofuranoside, their growth was significantly impaired compared with larvae reared on control spinach leaves. These results suggested that the flavonoid glycosides in B. alba leaves act as deterrents to S. litura larvae.

A new pregnane-type steroid, 2α-hydroxy-3α-methoxy-5α-pregnane (1), together with three known dammarane-type triterpenoid, 3β-acetyl-20S,24S-epoxy-25-hydroxydammarane (2), 20S,24S-epoxy-3α,25-dihydroxydammarane (3), and eichlerianic acid (4) have been isolated from the stem bark of Aglaia elliptica. The structure s were determined by spectroscopic methods including the 2D-NMR techniques. Compound 1-4 showed moderate cytotoxic activity against P-388 murine leukemia cells .

Three new meroterpenoid derivatives, furanocochlioqiunol (1) and furanocochlioqiunone (2), as well as nectrianolin D (3), together with two known biogenetically related compounds 4 and 5 were isolated from a mixed culture of two mangrove-derived fungi, Clonostachys rosea B5–2 and Nectria pseudotrichia B69–1. The structures of 1–3 were deduced based on the interpretation of HRMS and NMR data. Compounds 1–5 exhibited cytotoxicity against human promyelocytic leukemia (HL60) cells with IC50 values ranging from 0.47 to 10.16 μM.

Limonoids (tetranortriterpenoids) are triterpenoid compounds that lose four terminals in their structural framework. These compounds have a wide variety of structures and interesting activities including anti-inflammatory, anti-cancer, anti-tumor and anti-malarial properties. The purpose of this study was to find limonoid compounds from the Indonesian Chisocheton plant, and one of which is Chisocheton macrophyllus . The dried and powdered seeds of C. macrophyllus (4.5 kg) were extracted with methanol and partitioned successively with n -hexane, ethyl acetate and n -butanol. Evaporation of each extract resulted in the crude extracts of n -hexane (346.6 g), ethyl acetate (60.8 g) and n -butanol (14.6 g). The n -hexane fraction was subjected to a silica gel vacuum-liquid chromatography (VLC) column packed with silica gel 60 using gradient of n -hexane, ethyl acetate and methanol (10% stepwise) to afford thirteen fractions (A-M). Fraction F (4.4 g) was subjected to silica gel column chromatography using gradient of n -hexane and ethyl acetate (5% stepwise). Subfraction F5 (1.2 g) was chromatographed on a column of silica gel eluted with n -hexane: CH 2 Cl 2 : EtOAc (2:7.5:0.5) to give compound 1 (19.7 mg) and fraction H (1.8 g) was subjected to silica gel column chromatography using gradient of n -hexane and ethyl acetate (5% stepwise) as eluting solvent to give 2 (12.0 mg). Chemical structures of 1 and 2 were elucidated by spectroscopic methods and determined as 6 α -acetoxyepoxyazadiradione ( 1 ) and Dysobinin( 2 ). Dysobinin ( 2 ) showed weak cytotoxic activity against MCF-7 breast cancer cells with an IC 50 value of 228.15 μ M

800x600 Two mixture s of flavanoid compounds ( 1 and 2 ), a mixture of catechin ( 1a ) and epicatechin ( 1b ) , and a mixture of gallocatechin ( 2a ) and epigallocatechin ( 2b ) , were isolated from the active fraction of the stem bark of Aglaia elliptica methanol extract. The chemical structure of the compounds w as identified with spectroscopic data , including UV, IR, NMR ( 1 H, 13 C, DEPT 135°, HMQC, HMBC, 1 H- 1 H COSY) , and MS, and additionally compared with previously reported spectral data. All compounds were evaluated for their cytotoxic effects against P-388 murine leukemia cells. Compound 2 showed cytotoxicity against the P-388 murine leukemia cell , with an IC 50 value of 7.79 µg/mL, but compound 1 wa s found not to be active ( more than 100 µg/mL ) . Normal 0 false false false EN-ID X-NONE X-NONE

An α- l -rhamnosidase-encoding gene from Aspergillus oryzae, which belongs to the glycoside hydrolase family 78, was cloned and expressed in Pichia pastoris. SDS-PAGE of the purified recombinant α- l -rhamnosidase protein revealed smeared bands with apparent molecular mass of 90–130 kDa. After N-deglycosylation, the recombinant enzyme showed a molecular mass of 70 kDa. The enzyme exhibited optimal activity at a pH of 5.0 and a temperature of 70 °C. Specific activity of the enzyme was higher toward hesperidin than toward naringin, which consist of α-1,6 and α-1,2 linkages, respectively. The activity was also higher toward hesperidin than toward rutin, which consist of 7-O- and 3-O-glycosyl linkages of flavonoids, respectively. Kinetic analysis of the enzyme showed that the Michaelis constant (Km) was lowest toward rutin, moderate toward naringin, and higher toward p-nitrophenyl-α- l -rhamnopyranoside and hesperidin. Its high catalytic efficiency (kcat/Km) toward rutin was results of its low Km value while its high catalytic efficiency toward hesperidin was results of a considerably high kcat value.

The novel compound, 11-O-methylpetasitol (1), was isolated from Penicillium sp. N-175-1, and two new compounds, cosmochlorins D (5) and E (6), were isolated from Phomopsis sp. N-125. In addition, three known eremophilane sesquiterpenes, sporogen-AO1 (2), petasol (3) and 6-dehydropetasol (4), were isolated from Penicillium sp. N-175-1. The structures of 1, 5 and 6 were elucidated by a combination of extensive spectroscopic analyses, including 2D NMR, high-resolution electrospray ionization time-of-flight mass spectrometry (HRESITOFMS) and chemical reactions. Compounds 2, 3, 5 and 6 exhibited cytotoxicity to HL60 and 2 and 3 to HeLa cells. Furthermore, 2 and 3 showed robust growth-restoring activity of a Saccharomyces cerevisiae (cdc2-1 rad9Δ) mutant strain, whereas 5 and 6 exhibited minor growth-restoring activity in this strain. Thus, these compounds may inhibit the growth of HL60 and HeLa cells by blocking the cell cycle, and they may be utilized as new lead compounds that act as inhibitors of survival signal transduction pathways.

Two sesquiterpene-epoxycyclohexenone conjugates, nectrianolins A ( 1 ) and B ( 2 ), together with a sesquiterpene, nectrianolin C ( 3 ), were isolated from the brown rice culture of Nectria pseudotrichia 120-1NP, an endophytic fungus isolated from Gliricidia sepium . Their structures were determined on the basis of 1D-/2D-NMR spectroscopy and HRESIMS data analyses in combination with chemical means. Nectrianolins A–C ( 1 – 3 ) exhibited cytotoxic activity against both HL60 and HeLa cells.

Two new triterpene saponins, albidosides H (1) and I (2), along with the three known saponins were isolated from the barks of Acacia albida. Their structures were elucidated on the basis of extensive 1D- and 2D-NMR studies and mass spectrometry. Albidosides H (1) and I (2) were assayed for their cytotoxicity against HeLa and HL60 cells using MTT method.

Allantopyrone A is a fungal metabolite that uniquely possesses two α,β-unsaturated carbonyl moieties. We recently reported that allantopyrone A inhibited the nuclear factor-κB (NF-κB) signaling pathway induced by tumor necrosis factor (TNF)-α in human lung carcinoma A549 cells. In the present study, the mechanism by which allantopyrone A inhibits the TNF-α-induced signaling pathway was investigated in more detail. Allantopyrone A blocked extensive modifications to receptor-interacting protein 1 (RIP1) in the TNF receptor 1 (TNF-R1) complex. Allantopyrone A augmented the high-MW bands of TNF-R1, TNF receptor-associated factor 2, RIP1, the NF-κB subunit RelA and inhibitor of NF-κB kinase β in A549 cells, suggesting that it binds to and promotes the crosslinking of these proteins. The extracellular cysteine-rich domains of TNF-R1 were crosslinked by allantopyrone A more preferentially than its intracellular portion. The present results demonstrate that allantopyrone A interferes with multiple components of the TNF-R1 complex and blocks RIP1 modifications in the TNF-α-induced NF-κB signaling pathway.

The endophytic fungus

Two new naphthoquinone derivatives, 6-hydroxy-astropaquinone B (

A new antimalarial sterol, kaimanol (

A new antimalarial sterol, kaimanol (1), along with a known sterol, saringosterol (2) was isolated from the Indonesian Marine sponge, Xestospongia sp. The chemical structure of the new compound was determined on the basis of spectroscopic evidences and by comparison to those related compounds previously reported. Isolated compounds, 1 and 2 were evaluated for their antiplasmodial effect against Plasmodium falciparum 3D7 strains. Compounds 1 and 2 exhibited antiplasmodial activity with IC50 values of 359 and 0.250 nM, respectively.

Six new triterpenoid saponins, named senegalosides A–F (1–6) were isolated from the seedpods and roots of Acacia senegal (Mimosaceae). Their structures were elucidated using 1D and 2D-NMR spectroscopic analysis and mass spectrometry. Compound 1 possesses an unusual sapogenin, 3β-hydroxy-21-oxo-olean-12-en-28-oic acid (machaeric acid), and was reported here in its natural form for the first time within the genus Acacia. Senegaloside A is the first example of a machaeric-type triterpenoid glycoside in the plant kingdom. The cytotoxic effect of isolated saponins was evaluated on the H4IIE rat hepatoma cell line. As a result, compounds 1, 3–6 were not significantly cytotoxic to H4IIE cells even at 200 μM. Compound 2 was suppressed cell viability at 50–200 μM.

A pair of new diastereomeric isoindolinone alkaloids, spirocollequins A and B, were isolated from an endophytic fungus, Colletotrichum boninense AM-12-2. Their structures are featuring a 4,5-dihydro-spiro[furan-2,1′-isoindolin]-3′-one core. Their structures were determined by 1D/2D NMR, the Mosher’s ester method, and DFT-GIAO NMR chemical shift calculations, coupled with advanced statistical procedures. Spirocollequins A and B exhibited in vitro antiplasmodial activity at the IC50 (μM) values of 9.72 ± 0.61 and 4.71 ± 0.77, respectively.

Cosmochlorins A (1), B (2), and C (3) were isolated from the endophytic fungus Cosmospora vilior IM2-155. The structures of 1, 2, and 3 were elucidated by a combination of extensive spectroscopic analyses, including extensive 2D NMR, HRESITOFMS, and chemical reactions. Compounds 1, 2, and 3 were evaluated for their biological activity. Compounds 1 and 2 partially restored the growth inhibition caused by hyperactivated Ca2+-signaling in mutant yeast and showed glycogen synthase kinase (GSK)-3β inhibition activity at IC50 values of 62.5 and 60.6 μM, respectively. Further, compound 2 significantly increased osteoclast formation by more than 1.5-fold in RAW264.7 cells compared to receptor activator of nuclear factor-κB ligand (RANKL) alone.

The genome of Aspergillus oryzae encodes a hypothetical protein (annotated as AO090701000884), designated AoFaeD, which exhibits sequence identity to feruloyl esterases from Aspergillus clavatus, Coprinopsis cinerea, Neurospora crassa , and Pseudomonas fluorescens subsp. cellulosa . In this study, we cloned the AofaeD coding sequence into Pichia pastoris and demonstrated heterologous expression and secretion of active recombinant enzyme (rAoFaeD) as a 30-kDa protein in the culture medium. Purified rAoFaeD exhibited optimal activity at pH 7.0 and at 45 °C, but was stable at a pH range of 7.0–10.0 and a temperature of 40 °C. While wild-type rAoFaeD failed to cleave the methyl esters of ferulic acid (MFA), p -coumaric acid (M p CA), caffeic acid (MCA), and sinapic acid (MSA) and ethyl ester of ferulic acid (EFA), enzyme exhibited esterase activity when wheat arabinoxylan was used as a substrate, and this reaction was enhanced synergistically by the addition of xylanase. Notably, rAoFaeD variants in which one of the tryptophan residues (Trp142 or Trp144) located adjacent to the putative catalytic serine residue at position 143 (Ser143) was replaced with phenylalanine and tyrosine (W142F and W144Y), respectively, exhibited hydrolytic activity toward MFA, M p CA, MCA, MSA, and EFA. Moreover, these variants exhibited enhanced production of ferulic acid from wheat arabinoxylan compared to the wild-type protein, and the activity of these proteins was enhanced by the addition of xylanase.

Phytochemical investigation of the roots of Albizia chevalieri led to the isolation of two new 5-deoxyflavan-3,4-diol glucosides from roots of A. chevalieri, Chevalieriflavanosides A and B. Their structures were established by 2D NMR techniques, UV, IR, CD, and mass spectrometry. Cytotoxicity of the two compounds was evaluated against acute promyelocytic leukemia HL60 cells. The antibacterial activities of 1 and 2 also were evaluated against Pseudomonas aeruginosa and Staphylococcus aureus using the agar diffusion test. Copyright © 2016 John Wiley & Sons, Ltd.

Three novel benzenediol lactone derivatives, 7-hydroxy-14-de-O-methyl-lasiodiplodin (2), ethyl-3,5-dihydroxy-7-(6,8-dihydroxynonyl)benzoate (4), and 7-ethylbenzoate-7-heptanoic acid (5), together with known compounds, 14-de-O-methyl-lasiodiplodin (1) and ethyl-3,5-dihydroxy-7-(8-hydroxynonyl)benzoate (3), were isolated from the culture of Fusarium solani T-13, a fungus from a dead branch. Their structures were elucidated using 1D- and 2D-NMR spectroscopy. Compounds 1, 3 and 4 showed doughnut like phenotypes of growth restoring activity against the mutant yeast (zds1ο erg3ο pdr1/3ο) at the concentration of 0.16, 0.63 and 1.25 μg/spot, respectively.

Keap1-Nrf2 system is known as a sensor of electrophilic compounds, and protects cells from oxidative stress through induction of various antioxidant enzymes. We found by proteomic analysis that allantopyrone A, a metabolite isolated from an endophytic fungus, upregulates the expression of proteins that are regulated by the transcription factor Nrf2. Indeed, allantopyrone A increased the antioxidant enzyme heme oxygenase-1 in PC12 cells. Moreover, it induced localization of Nrf2 in the nucleus. Affinity purification of allantopyrone A-binding protein showed that this compound could bind directly to Keap1. Allantopyrone A suppressed intracellular reactive oxygen species level and cell death induced by H2O2 in PC12 cells. These results indicate that allantopyrone A protects PC12 cells from oxidative stress-induced cell death through direct binding with Keap1 and activation of the Keap1-Nrf2 pathway.

One new polyketide derivative, heptacyclosordarianone (1), together with 2 known compounds, heptacyclosordariolone (2) and sordariol (3), were isolated from an extract of Sordaria sp. AM-71, an endophytic fungus inhabiting Garcinia polyantha. The structures of these compounds were elucidated based on intensive nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry and by comparison with literature data. All compounds were assayed for their antimicrobial and cytotoxic properties. Only compound 2 showed antimicrobial activities against Bacillus subtilis DSMZ 704 , Pseudomonas agarici DSMZ 11810, and Micrococcus luteus DSMZ 1605 with minimum inhibitory concentration values of 9.3, 15.5, and 16.9 µg/mL respectively. None of the isolated compounds showed a significant cytotoxic property.

Three aromadendrane-type sesquiterpenoids, spathulenol ( 1 ), 4β,10α-dihydroxyaromadendrane ( 2 ), and 4α,10α-dihydroxyaromadendrane ( 3 ) were isolated from the stem bark of Aglaia harmsiana (Meliaceae). Compound 3 was isolated for the first time from Aglaia genus. The chemical structures of isolated compounds were elucidated by various spectroscopic methods, including one and two-dimensional NMR, as well as mass spectroscopy analysis. These sesquiterpenoids 1 - 3 were evaluated for their cytotoxic activity against MCF-7 breast cancer cell lines. The IC 50 value of compound 1 - 3 were 31.65 ± 0.1, 8.41 ± 0.04 and 2.80 ± 0.02 µM, respectively. Among the aromadendrane-type sesquiterpenoids, compounds 2 and 3 , which do not have a double bond, showed higher activity than compound 1 . Whereas, compound 3 showed the strongest activity indicate that α configuration of hydroxyl group increases the cytotoxic activity.

Two dammarane-type triterpenoids, cabraleadiol (1) and cabraleahydroxylactone (2), have been isolated from n-hexane extract of the stembark of Chisocheton pentandrus (Meliaceae). The structure of compounds 1 and 2 were determined by spectroscopic data mainly NMR and mass as well as by comparing with previously reported spectral data. Compounds 1 and 2 were reported for the first time from Chisocheton pentandrus. Keywords: Cabraleadiol, Cabraleahydroxylactone, Chisocheton pentandrus, Meliaceae.

Lambertellin (1) and ergosta-5,7,22-trien-3-ol (2) were isolated from the solid rice fermentation of the plant pathogenic fungus Pycnoporus sanguineus MUCL 51321. Their structures were elucidated using comprehensive spectroscopic methods. The isolated compounds were tested on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Lambertellin (1) exhibited promising inhibitory activity against nitric oxide (NO) production with IC50 value of 3.19 µM, and it significantly inhibited the expression of inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2). Lambertellin (1) also decreased the expression of pro-inflammatory cytokines IL-6 and IL-1β. The study of the mechanistic pathways revealed that lambertellin (1) exerts its anti-inflammatory effect in LPS-stimulated RAW 264.7 macrophage cells by modulating the activation of the mitogen activated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling pathways. Therefore, lambertellin (1) could be a promising lead compound for the development of new anti-inflammatory drugs.

Four new compounds, namely, nectriapyrones A (2) and B (3), nectriaquinone B (5), and zythiostromic acid C (8), were isolated from the brown rice culture of Nectria pseudotrichia 120-1NP together with four known compounds (1, 4, 6, and 7). To the best of our knowledge, this is the first report of 4 from a natural source. Their structures were determined on the basis of 1D/2D-NMR spectroscopy and HRESITOFMS data. In addition, the absolute configuration of secondary alcohols in 8 were determined using modified Mosher's ester method. All isolated compounds were evaluated for their antimicrobials activity, phytotoxicity, and cytotoxicity.

One new depsidone, polyanthadepsidone A (1), together with four known compounds were isolated from the dichloromethane extract of the leaves of Garcinia polyantha. The structures of all compounds were determined by comprehensive analyses of their 1D and 2D NMR and EI mass spectral data. All the isolates exhibited suppressive effect on phagocytosis response upon activation with serum opsonised zymosan in the IC50 range of 4.5–23.80 μM, tested in vitro for oxidative burst studies of whole blood.

Four new compounds, phomadecalin F (1), 8α-monoacetoxyphomadecalin D (2), 3-epi-phomadecalin D (3), and 13-hydroxylmacrophorin A (4), were isolated from the endophyte, Microdiplodia sp. TT-12 together with two known compounds, phomadecalins C (5) and D (6). The structures of the compounds were elucidated by NMR spectroscopic and mass spectrometric analyses in combination with chemical means. The antibacterial activities of the isolated compounds were evaluated. Compound 4 was weakly active against Raffaelea quercivora.

Four novel compounds, cylindropyrone A (1), 10'-hydroxyilicicolinic acid D (3), cylindrolactones A (4) and B (5), together with known dihydroinfectopyrone (2) were isolated from the culture of Cylindrocarpon sp. SY-39 from a driftwood. Their structures were elucidated using 1D- and 2D-NMR spectroscopy. Compound 3 showed antimicrobial activity against Staphylococcus aureus with MIC value of 5.0 μg/mL.

α-L-Rhamnosyl-β-D-glucosidase (rutinosidase) hydrolyzes the glycosidic linkage between the disaccharide 6-O-α-L-rhamnosyl-β-D-glucoside (rutinose) and the aglycone. We identified a hypothetical protein (annotated as AO090012000917) encoded in the Aspergillus oryzae genome that exhibits sequence similarity with Aspergillus niger rutinosidase. The recombinant enzyme was expressed in Pichia pastoris GS115 and purified as a glyco-protein with apparent molecular mass of 65–75 kDa by SDS-PAGE. After N-deglycosylation, we observed a 42- and 40-kDa band, representing proteins before and after N-terminal signal peptide processing, respectively. Optimal enzymatic activity was observed at pH 4.0 and temperature of 45 °C. This enzyme is also significantly thermo-stable, with 90% activity retained after 1 h at 45 °C and 70% activity retained after 4 h, even at 50 °C. Biochemical characterization revealed that the enzyme has higher substrate specificity for 3-O-linked flavonoid β-rutinosides like rutin and kaempferol-3-O-rutinoside, than for 7-O-linked flavonoid β-rutinoside like hesperidin. However, no activity was found with naringin, diosmin, monoglycosylated chromogenic substrates, and polymeric laminarin substrate. Kinetic analyses showed that K m value toward rutin was higher than those toward hesperidin and kaempferol-3-O-rutinoside. Meanwhile, kcat value toward hesperidin was lower than those toward kaempferol-3-O-rutinoside and rutin. Overall, the catalytic efficiency (kcat/K m ) was highest for kaempferol-3-O-rutinoside.

Three new fusarielins, 3-epi-fusarielin H (1), 3-O-methyl-fusarielin H (2), and 3-O-methyl-epi-fusarielin H (3), were isolated from the fungus Fusarium sp. together with the known analogues, fusarielins F (4) and G (5). The structures of these compounds were elucidated by analysis of their ESI-HRTOFMS, 1D and 2D NMR spectroscopic data. The new compounds exhibited weak antibacterial effect against Staphylococcus aureus.

A new eremophilane sesquiterpene, 13,13-dimethoxyintegric acid (1), together with known compound integric acid (2) have been isolated from a fungus, Xylaria sp. V-27, obtained from a dead branch. The structure of 1 was established by means of spectroscopic analyses. 1 and 2 promoted growth restoring activity against the mutant yeast strain (Saccharomyces cerevisiae (zds1Δ erg3Δ pdr1Δ pdr3Δ)) and inhibited degranulation of rat basophilic leukemia RBL-2H3 cells stimulated by immnunoglobulin G + 2,4-dinitrophenylated-bovine serum albumin (IgE+DNP-BSA), thapsigargin and A23187.

Seven previously undescribed bidesmosidic triterpenoid saponins named albidosides A - G, were isolated from a methanol extract of the roots of Acacia albida. Their structures were elucidated using 1D and 2D NMR spectroscopy and mass spectrometry and determined to be bidesmosides of oleanolic acid and of 16 alpha-hydroxyoleanolic acid. Albidosides B - G were assayed for their cytotoxicity against HeLa and HL60 cells using MTT method and microscopic observation. (C) 2016 Elsevier Ltd. All rights reserved.

A new compound, (3aS,6aR)-4,5-dimethyl-3,3a,6,6a-tetrahydro-2H-cyclopenta [b]furan-2-one (2), along with two known metabolites, myrotheciumone A (1) and 4-oxo-4H-pyron-3-acetic acid (3) was isolated from the ethyl acetate extract of fermentation broth of Xylaria curta 92092022. The structures of these compounds were elucidated on the basis of spectroscopic methods (UV, IR, HRESITOFMS, 1D NMR, and 2D NMR). Compounds 1 and 2 showed moderate antibacterial and phytotoxic activities.

A new α-pyrone derivative, compound 2, and a known one, cladobotrin V, were isolated from the culture broth of the mangrove endophyte Fusarium sp. IM-37. Their structures were determined spectroscopically and compared with previously reported spectral data. Compound 2 restored the growth inhibition caused by hyperactivated Ca(2+)-signaling in mutant yeast.

In this study, the biochemical properties of the recombinant tannase from Aspegillus oryzae were compared with those of the native enzyme. Extracellular native tannase was purified from a commercial enzyme source. Recombinant tannase highly expressed in Pichia pastoris was prepared as an active extracellular protein. Purified native and recombinant tannases produced smeared bands with apparent molecular masses of 45–80 kDa and 45–75 kDa, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After N -deglycosylation, the native enzyme yielded molecular masses of 33 kDa and 30 kDa, whereas the recombinant enzyme yielded molecular masses of 34 kDa and 30 kDa. Purified native and recombinant tannases had an optimum pH of 4.0–5.0 and 5.0, respectively, and were stable up to 40°C. After N -deglycosylation, both enzymes exhibited reduced thermostability. Catalytic efficiencies of both purified enzymes were greater with natural substrates, such as (−)-catechin, (−)-epicatechin, and (−)-epigallocatechin gallates, than those with synthetic substrates, such as methyl, ethyl, and propyl gallates. However, there were no activities against the methyl esters of ferulic, p -coumaric, caffeic, and sinapic acids, which indicate feruloyl esterase activity, or the ethyl, propyl, and butyl esters of 4-hydroxybenzoic acid, which indicate paraben hydrolase activity.

Four new polyketides, fusopoltides B–E, were isolated, along with four known compounds, from Fusarium solani B-18 cultured on brown-rice. Fusopoltide B is a diastereomer of its co-isolated known compound, fusopoltide A, featuring a pentaleno[1,2-c]pyran ring system. Fusopoltide C and fusopoltides D–E are incorporated the first natural polyketides featured decahydro-pentaleno[1,2-c]pyran and pentaleno[1,2-c]furan ring systems, respectively. The structural assignments were established using comprehensive spectroscopic techniques, the modified Mosher's ester method, and electronic circular dichroism (ECD) calculations.

Two new isopimarane-type diterpenes, spiropolin A (1) and myrocin E (3), were isolated from Xylaria polymorpha together with the known compound, myrocin D (2), in the course of a screening of the fruiting bodies of X. polymorpha. Their structures were determined on the basis of spectroscopic analysis, chemical conversion and X-ray analysis. Spiropolin A (1) restored the growth inhibition caused by the hyperactivated Ca2+-signaling in mutant yeast.

A new polyketide, fusaequisin A (1), was isolated from rice cultures of Fusarium equiseti SF-3-17, an endophytic fungus previously discovered during screening of medicinal plants in Cameroon. The structure of 1 was determined using spectroscopic methods. Fusaequisin A (1) exhibited moderate antimicrobial activity against Staphylococcus aureus NBRC 13276 and Pseudomonas aeruginosa ATCC 15442 at a concentration of 200 μg per disk.

Aspergillus oryzae tannase (AoTanA), which contains two Kex2 recognition sites at positions Arg311 and Arg316, consists of two subunits that are generated by the cleavage of tannase gene product by the Kex2 protease. Based on the crystal structure of feruloyl esterase from Aspergillus oryzae (AoFaeB), which has been classified as a member of the fungal tannase family, the catalytic triad residues of AoTanA are predicted to be Ser195, Asp455, and His501, with the serine and histidine residues brought together by a disulfide bond of the neighboring cysteines, Cys194 and Cys502. In this study, we investigated the functional role of the Kex2 recognition sites and disulfide bond between the neighboring cysteines in AoTanA. We constructed a double variant (R311A/R316A), a seven amino-acid deletion variant of region Lys310-Arg316 (ΔKR), and two single variants (C194A and C502A). While the R311A/R316A variant exhibited the two bands similar to wild type by SDS-PAGE after treatment with endoglycosidase H, the ΔKR variant exhibited only one band. R311A/R316A variation had no effect on tannase activity and stability. Meanwhile, the ΔKR variant exhibited higher activity compared to the wild-type. The activities of the C194A and C502A variants decreased considerably (

Phytochemical investigation of the roots of Albizia chevalieri led to the isolation of two new 5-deoxyflavan-3,4-diol glucosides from roots of A. chevalieri, Chevalieriflavanosides A and B. Their structures were established by 2D NMR techniques, UV, IR, CD, and mass spectrometry. Cytotoxicity of the two compounds was evaluated against acute promyelocytic leukemia HL60 cells. The antibacterial activities of 1 and 2 also were evaluated against Pseudomonas aeruginosa and Staphylococcus aureus using the agar diffusion test. Copyright © 2016 John WileySons, Ltd.