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Various bioactive polyketides have been found in Aloe barbadensis. However, the polyketide synthases (PKSs), which participate in biosynthesis of polyketides in A. barbadensis remain unknown. In this study, two type III PKSs (AbPKS1 and AbPKS2) were identified from A. barbadensis. AbPKS1 and AbPKS2 were able to utilize malonyl-CoA to yield heptaketides (TW93a and aloesone) and octaketides (SEK4 and SEK4b), respectively. AbPKS1 also exhibited catalytic promiscuity in recognizing CoA thioesters of aromatics to produce unusual polyketides. What Is more, a whole cell biocatalysis system with the capability of producing 26.4 mg/L of SEK4/SEK4b and 2.1 mg/L of aloesone was successfully established. [ABSTRACT FROM AUTHOR]

Glucuronidation is an important and popular metabolic reaction in vivo of drugs. The further evaluation of biological activity and toxicity of glucuronides is necessary in the course of the drug research and development. However, the synthesis of glucuronides is limited by the lack of efficient approach. Herein, we have developed a new glucuronide synthesis method using plant uridine diphosphate-dependent glucuronosyltransferases (UGTs), UGT88D4, UGT88D7, and EpGT8, enabling the convenient preparation for corresponding O-glucuronide metabolites (1a, 2a, 3a, and 3b) in milligram scale of two neurological active agents, IMM-H004 (1) and FLZ (2). Their structures were characterized by spectroscopic data analyses. [ABSTRACT FROM AUTHOR]

Anhydroicaritin (1a), baohuoside (1b) and icariin (1c) were recognized as major pharmacologically active ingredients of Epimedium plants. Their primary means of acquisition were chemical isolation from plants. However, it suffers from low yield, environmental pollution and shortage of plants. Herein, to remedy these problems, biosynthesis was explored to obtain the three active ingredients. Fortunately, with SfFPT as 8-prenyltransferase, EpPF3RT and Ep7GT as glycosyltransferases, kaempferide (1) was transferred to 1a, 1b and 1c enzymatically. Thus, we report the details of this method. This approach represents a promising environmental friendly alternative for the production of these compounds from an abundant analogue. [ABSTRACT FROM AUTHOR]

Cytochrome P450 enzymes are responsible for the biotransformation and elimination of numerous xenobiotics, while they can also metabolically activate potential toxicants. As such, proper modulation on CYP450s provides a possible way to block chemical-induced toxicity. The biological benefits of garlic have been extensively studied, and the chemoprotective effects have been disclosed by using different garlic preparations including intermixtures as well as single components, in which the regulation on CYP450s (especially the inhibition of CYP2E1) is believed to be, at least partially, responsible for the chemoprotection. However, a number of studies also indicate the activation of several CYP450s (CYP3A, 2B and 1A1/2). As such, the concomitant use of the garlic products with some clinical drugs is questioned. Since most of the current data are obtained from experimental studies and the doses used are quite high, it is important to investigate the potential effects of garlic ingredients at lower doses. In addition, the dose- and time- dependent responses as well as much more clinical studies are needed. Furthermore, as the organosulfur compounds may work synergistically, it is of significance to investigate the potential effects of the commercially available garlic products (garlic oil, garlic powder, etc). [ABSTRACT FROM AUTHOR]

The hydropyrolysis of light hydrocarbons were carried out in H2/Ar plasma jet at atmosphere pressure and average temperature between 1500K and 3000K. The raw material was Liquefied Petroleum Gas. The experimental results show that among all the pyrolysis products, major product is acetylene. Carbon black is the byproduct. The yield and selectivity of acetylene can reach 74%, 80%, respectively. Carbon black is characterized with XRD, TEM, and adsorption-and-desorption of liquid nitrogen, respectively. [ABSTRACT FROM AUTHOR]

Short-chain dehydrogenase/reductases (SDRs) belong to the NAD(P)(H)-dependent oxidoreductase superfamily, which have various functions of catalyzing oxidation/reduction reactions and have been generally used as powerful biocatalysts in the production of pharmaceuticals. In this study, ScSDR1 and ScSDR2, two new SDRs have been identified and characterized from Stachybotrys chartarum 3.5365. Substrate scope investigation revealed that both of the enzymes possessed the ability to oxidize β-OH to ketone specifically, and exhibited substrate promiscuity and high stereo-selectivity for efficiently catalyzing the structurally different prochiral ketones to chiral alcohols. These findings not only suggest that ScSDR1 and ScSDR2 might be potent synthetic tools in drug research and development, but also provide good examples for further engineered enzymes with higher efficiency and stereo-selectivity. [ABSTRACT FROM AUTHOR]

Nine representative limonoids isolated fromTurraae pubescenswere investigated by electrospray ionization quadrupole time-of-flight tandem mass spectrometry in positive ion mode. Although the structures of these compounds are similar, the corresponding fragmentation patterns and mass spectrometry and tandem mass spectrometry (MS/MS) spectra are clearly different. For Turrapubin A–C, product ions can be detected in both low and high mass ranges. A McLafferty-type rearrangement is the only way for the cleavage of C9–C10. For 11-epi-toonacilin, Turrapubin E, Turraflorin A, 11-epi-23-hydroxytoonacilide, Turrapubin H and 11-epi-21-hydroxytoonacilide, the cleavage of C9–C10 goes through two different ways, including McLafferty-type rearrangement and homolytic cleavage. The relative abundances of product ions from McLafferty-type rearrangement for 11-epi-toonacilin, 11-epi-23-hydroxytoonacilide, and Turrapubin H are high, while those for Turrapubin E, Turraflorin A, and 11-epi-21-hydroxytoonacilide are low. A pair of epimers was distinguished unambiguously by MS/MS spectra. It was found that the substituent group at C-1, hydroxy group, O atom linked to C-14 and C-15, and the oxygenated furan ring were the important factors leading to the differences of their MS/MS spectra. [ABSTRACT FROM PUBLISHER]

Peridecalins C and D (1 and 2), one decalin and one oxygen-decalin containing polyketide-amino acid hybrids with 5/6/6 ring system, was isolated from a genetic mutant of Periconia sp. F-31. Their structures were elucidated through extensive spectroscopic data analysis, including 1 D/2D NMR and HR-MS spectra. Biosynthetically, two proposed Diels-Alder reactions are supposed to be involved in the skeleton construction of 1 and 2. [ABSTRACT FROM AUTHOR]

One new eremophilane sesquiterpene periconianone L (1), together with four known guaiane-type sesquiterpenes 4,10,11-trihydroxyguaiane (2), (−)-guai-1(10)-ene-4α,11-diolhydroxymecuration (3), guaidiol A (4), and epi-guaidiol A (5) were isolated from the endophytic fungus Periconia sp. F-31. The structure of the new compound was established by spectroscopic methods, including UV, IR, HRESIMS, and extensive NMR techniques. Compound 3 was isolated as natural product for the first time. [ABSTRACT FROM AUTHOR]

A novel hetero-hexanuclear [CuII4GdIII2] complex with a symmetrical bis(salamo)-like tetraoxime ligand (H4L), [{Cu2(L)(MeOH)Gd(NO3)2(μ2-NO3)}2]·2CH3OH was obtained after careful design and synthesis. The structure of the [CuII4GdIII2] complex was adequately characterized by elemental analysis, FTIR, and UV–vis spectroscopy. The [CuII4GdIII2] complex crystallized in the monoclinic system, space group C2/c embraces four CuII ions with two coordination geometries: tetragonal pyramid and octahedron, two GdIII ions with nine coordinated tricapped trigonal prism geometry, two completely deprotonated octadentate (L)4– units, two coordinated methanol molecules, two bidentate bridging nitrate groups (μ2-NO3–), four bidentate chelating nitrate groups and two crystallized methanol molecules. The [CuII4GdIII2] complex ultimately constructs infinite 2D and 3D supramolecular structures via the intermolecular hydrogen bond interactions. Meanwhile, the fluorescence properties of the ligand (H4L) and its [CuII4GdIII2] complex were studied. The electronic structure and stability of the [CuII4GdIII2] complex were proved by density functional theory calculation. [ABSTRACT FROM AUTHOR]

A new triterpenoid saponin acylated with monoterpenic acid, together with two known triterpenoid saponins, has been isolated from the fruit of Gymnocladus chinensis Baill. Their structures were elucidated as 2β,23-dihydroxy-3-O-α-L-rhamnopyranosyl-21-O-{(6S)-2-trans-2,6-dimethyl-6-O-[3-O-(β-D-glucopyranosyl)-4-O-((6S)-2-trans-2,6-dimethyl-6-hydroxy-2,7-octadienoyl)-β-L-arabinopyranosyl]-2,7-octadienoyl}-acacic acid 28-O-β-D-xylopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)-[α-L-rhamnopyranosyl-(1 → 6)]-β-D-glucopyranosyl ester (1), gymnocladus saponin E (2), and gymnocladus saponin F2 (3). [ABSTRACT FROM AUTHOR]

The effect of Fe 3+ doping level on the surface properties and catalytic performance of a series of iron-doped titanium oxide catalysts (1–7 mol% Fe 3+ ) prepared using an acid-catalyzed sol-gel method was investigated in oxidative dehydrogenation of ethylbenzene with CO 2 . The characterization of catalysts was carried out by means of x-ray powder diffraction (XRD), temperature programmed reduction (TPR), and the method of Brunauer, Emmett, and Teller (BET). It was found that the capacity of isolated Fe 3+ centers in titania matrix is responsible for the catalytic performance; the catalysts exhibit the best activity at the loading level of Fe 3+ , about 3 mol%. In addition, it was shown that the appropriate pore size of the catalysts ranges from 5 nm to 25 nm; the selectivity to styrene increases with an increase in the specific surface area of the appropriate pores. [ABSTRACT FROM AUTHOR]

Bistachybotrysin K (1), one new phenylspirodrimane dimer with a central 6/7 oxygen heterocycle core, was isolated from the fungus Stachybotrys chartarum CGMCC 3.5365. Its structure was elucidated by extensive spectroscopic data and single-crystal X-ray diffraction. Compound 1 showed significant cytotoxicity against human tumor cell lines HCT116, NCI-H460, BGC823, Daoy, and HepG2 with IC50 values in the range of 1.1–4.7 µM. [ABSTRACT FROM AUTHOR]

Context: We previously reported a novel tumour associated antigen (TTA) with molecular weight around 48 kDa and identified the novel TTA as a fragment derived from human DNA-topoiomerase I (TOP1). We termed the novel TAA as TOPO48 and termed autoantibody against the TAA as anti-TOPO48 autoantibody. Objective: To explore the clinical significance of anti-TOPO48 autoantibody in patients with colorectal carcinoma (CRC). Materials and methods: Serum levels of the autoantibody in patients with CRC or benign tumours and healthy volunteers were measured with a specific ELISA. Results: CRC patients at early stage had higher frequency of positive levels of the autoantibody and CRC patients with positive autoantibody levels had higher overall survival rate than those with negative autoantibody levels. Conclusion: The autoantibody is a potential biomarker for early diagnosis and favourable prognosis of CRC. [ABSTRACT FROM AUTHOR]

Three new phenylspirodrimanes derivatives named stachybotrysins H and I (1 and 2) and stachybotrin E (3), together with one known compound stachybotrylactam (4), were isolated from Stachybotrys chartarum CGMCC 3.5365. Their structures were determined by extensive NMR data and mass spectroscopic analysis. Compounds 1 and 2 showed inhibitory effect towards potassium channel Kv1.3 with IC50 values of 13.4 and 10.9 μM, respectively. [ABSTRACT FROM AUTHOR]

A strategy developed for obtaining positive cellular responses remains to be focused in the filed of functional biomimetics. In this study, a hydrogel covered simvastatin-loaded polyetheretherketone (PEEK) bio-composites was constructed with the purpose of bone tissue regeneration therapy. Briefly, a three-dimensional (3D) porous structure was fabricated on PEEK surface; then the substrate was functionalized with the poly(L-lactic acid)/simvastatin porous film and hyaluronic acid hydrogel subsequently. In vitro cell attachment, proliferation, and cytoskeletal observation experiments reveal that our scaffolds show better bio-affinity due to the layer of hyaluronic acid hydrogel compared with control. Furthermore, the alkaline phosphatase activity, calcium mineral deposition evaluation, and gene expression for osteogenic potential all exhibit that the superior osteogenic differentiation of MC3T3-E1 pre-osteoblasts on our scaffolds. Therefore, our PEEK samples loaded with simvastatin and covered with hyaluronic acid hydrogel hold great potential in clinical applications for bone repair. [ABSTRACT FROM AUTHOR]

Two new lanostane triterpenoids (1 and 2), two new ergostane-type steroids (3 and 4) together with two known lanostane triterpenoids (5 and 6) and one known steroid (7) were isolated from the cultured mycelia of Ganoderma capense (CGMCC 5.71). Their structures were determined on the basis of extensive spectroscopic (HRESIMS, 1D NMR, 2D NMR) data analyses. Compound 1 exhibited moderate cytotoxic activity against the human cancer cell line NCI-H1650 with an IC50 value of 22.3 μM, and 7 displayed cytotoxic activity against the human cancer cell line HCT116 with an IC50 value of 17.4 μM. In addition, compounds 2, 3, 5, and 6 displayed weak anti-HIV activity with IC50 values of 23.5, 46.7, 21.6, and 30.1 μM, respectively. [ABSTRACT FROM AUTHOR]

A new steroid glucoside (1), along with nine known steroids (2–10) and four known sorbicillinoids (11–14), were isolated from the endophytic fungusTrichodermasp. Xy24. Their structures were elucidated on the basis of spectroscopic data analyses and by comparison with reported data. Compounds3,5–7,9,10, and13exhibited significant inhibitory effects on HIV-1 virus with IC50values ranging 1.9–9.3 μM; compounds10,13, and14showed potent inhibitory activity on LPS-induced NO production in BV2 microglia cells with inhibitory rates of 108.2, 100, and 75.1% at 10 μM, respectively. In addition, compound10displayed moderate cytotoxicity against BCG823 and HePG2 cell lines with IC50values of 11.1 and 17.7 μM, respectively. [ABSTRACT FROM AUTHOR]

Three new sesquiterpenoids trichoacorenols B–C and cyclonerodiol B (1–3), along with three known ones (4–6), were isolated from the mangrove plant endophytic fungusTrichodermasp. Xy24 using various column chromatography techniques. The structures of these compounds were determined on the basis of extensive spectroscopic data analyses. Compounds1,2,4, and5were four acorane sesquiterpenes,3and6were two monocyclic sesquiterpenediols. Compounds3and5exhibited significant neural anti-inflammatory activity by inhibiting LPS-induced NO production in BV2 cells with the inhibitory rates of 75.0% and 39.2% at 0.1 μM, respectively, which are more potent than curcumin, a positive control with the inhibitory rate of 21.1% at 0.1 μM. [ABSTRACT FROM PUBLISHER]

Five monoterpenoids were isolated from the endophytic fungusPericoniasp. F-31, including three new carene-type monoterpenoids, 2-carene-5,8-diol (1), 2-carene-8,10-diol (2), 2-carene-8-acetamide (3), one new menthene-type monoterpenoid 8-hydroxy-1,7-expoxy-2-menthene (4), and one known monoterpenoid anethofuran (5). The structures of all compounds were elucidated based on a comprehensive spectroscopic data analysis, electronic circular dichroism (ECD), and calculated ECD. [ABSTRACT FROM PUBLISHER]

Garlic has long been the focus of experimental and clinical attentions due to its promising lipid-lowering effects. Numerous animal studies as well as in vitro ones have demonstrated the hypolipidemic effects of garlic, while clinical trials are highly inconsistent. Based on some double-blind, randomized, placebo-controlled clinical trials which denied the hypolipidemic effects of garlic, some meta-analysis concluded that garlic did not possess beneficial effects for hyperlipidemia. However, we should not ignore the abundant supporting data in the literature. It should be noted that the doses of garlic used in clinical trials were usually far lower than those used in animal studies, which might cover its potential effects. The type of the garlic products may be another important factor responsible for the conflicting outcomes, as different garlic products are composed of different organosulfur compounds. In addition, the biological availability of garlic products is of importance, which was omitted in many studies. Moreover, some studies indicated that different people might have a different response to garlic, and thus garlic may be more beneficial for some specific groups. Collectively, it may be inappropriate to draw a conclusion that garlic does not benefit for hyperlipidemia. Future studies with larger samples are needed to further clarify the effects of garlic used at higher but non-toxic doses on specific groups. [ABSTRACT FROM PUBLISHER]

Garlic has long been the focus of experimental and clinical attentions due to its promising lipid-lowering effects. Numerous animal studies as well as in vitro ones have demonstrated the hypolipidemic effects of garlic, while clinical trials are highly inconsistent. Based on some double-blind, randomized, placebo-controlled clinical trials which denied the hypolipidemic effects of garlic, some meta-analysis concluded that garlic did not possess beneficial effects for hyperlipidemia. However, we should not ignore the abundant supporting data in the literature. It should be noted that the doses of garlic used in clinical trials were usually far lower than those used in animal studies, which might cover its potential effects. The type of the garlic products may be another important factor responsible for the conflicting outcomes, as different garlic products are composed of different organosulfur compounds. In addition, the biological availability of garlic products is of importance, which was omitted in many studies. Moreover, some studies indicated that different people might have a different response to garlic, and thus garlic may be more beneficial for some specific groups. Collectively, it may be inappropriate to draw a conclusion that garlic does not benefit for hyperlipidemia. Future studies with larger samples are needed to further clarify the effects of garlic used at higher but non-toxic doses on specific groups. [ABSTRACT FROM AUTHOR]

In this paper, the concentration scanning phase diagram and the fishlike phase diagrams for the quaternary system of alkyl polyglucoside (APG: C8G1.46 or C8/10G1.31)/alcohol/alkane/water mixtures have been studied. By a mass-balance the mass fractions of APG and alcohol at the interface in the microemulsion (CS and CA) were obtained.The mixing fraction of alcohol at the interface (AS) was also determined by the HLB plane equation based on the geometrical relation of the three-phase tie triangle in the composition tetrahedron. The net solubilizing power γE is larger for C8/10G1.31 than that for the C8G1.46 microemulsion system. The effect of alcohol on the three-phase behavior and maximum solubilization was also investigated, which shows that alcohols with short chains have high solubilizing power. [ABSTRACT FROM AUTHOR]