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Novel enzyme source is essential in biomimetic synthesis. Use of peanut peroxidase in mediation of oxidative polymerization of phenolic compounds is meager. In this study, the 5 day-germinated peanut embryos were homogenized, centrifuged to collect supernatant and (NH4)2SO4 fractionated, the 40–75% saturated fraction exhibited most peroxidase activities. After UF-concentration between MWCO 300 and 10 kDa, Sephacryl S300 gel filtration and DEAE-Sephadex A25 ion-exchange, a 50.6-fold-purified peroxidase with 32 kDa in SDS-PAGE analysis was obtained. The freeze-dried and pulverized into powder (GPEP) bearing potent peroxidase activities was used in biomimetic resveratrol dimerization. In a semi-continuous system mediated by 0.5 g GPEP suspended in phosphate buffer (pH 7.4) with continuous feedings of resveratrol dissolved in acetone and aqueous H2O2 solution for 150 min, all added resveratrol reacted. After subjecting the reactant to SPE C18 cartridge clean-up, semi-HPLC purification and NMR 1- and 2D spectroscopic elucidation, a dimeric product was identified as δ-viniferin with ca. 60% of recovery. The δ-viniferin exhibited potent trolox equivalent antioxidant capacity as did BHT. It is of merit to demonstrate GPEP as a potential peroxidase source enabling scalable biomimetic production of δ-viniferin.

In this manuscript, reactions of γ-benzyloxy vinylogous urethanes under LDA deprotonation condition undergoing an [1,2]-Wittig rearrangement, followed by the lactonization to provide γ-benzyl vinylogous urethane lactones were studied. Those vinylogous urethane lactones can be facilely transformed into γ-benzyl butenolides. The easy operation of [1,2]-Wittig rearrangement/lactonization in our system, following the swift removal of pyrrolidine moiety in providing clear targets of various γ-benzyl butenolides demonstrated the true advantage of our studies, since previous [1,2]-Wittig rearrangement studies would normally provide products either lack of or not easy to foresee their synthetic applications. Applications of resulting γ-benzyl butenolides were concisely demonstrated in the formal synthesis of maculalactone A, synthesis of BCD ring of planchol C and the total synthesis of γ-lycorane.

The anti-selective aldol reaction of chiral alcohol-substituted γ-benzyloxy vinylogous urethanes is described. The use of (1S,2R,4R)-1-(hydroxydiphenylmethyl)-7,7-dimethylbicyclo[2,2,1]-heptan-2-ol as a chiral auxiliary in the aldol reaction of a vinylogous urethane enolate was found to provide anti-products in good yields with moderate to excellent enantioselectivities. The major anti-vinylogous urethane lactones were transformed into 3-benzyloxyl-4-hydroxylalkan-2-ones in good yields.

Along with clinical benign prostatic enlargement (BPE) management, searching for dietary supplements to relieve and/or prevent syndrome is needed. In this study, the orchiectomized Sprague-Dawley rats were fed with diets supplemented with bio-elicited peanut sprout powder (BPSP) and testosterone injected to mediate BPE. The mediated prostate/body ratio increase was significantly inhibited by diets supplemented with 3.2 g BPSP kg−1 bw. Prostatic catalase and superoxide dismutase activities of the rats fed with 3.2 and 6.4 g kg−1 bw were significantly higher than rats fed with 0 g kg−1 bw. As BPSP subjected to extraction, purification and instrumental elucidation, three new natural compounds were assigned and their antioxidative capacities at 100 µM were equivalent to 93.6, 83.9 and 84.7 µM of trolox, respectively. The new identified potent antioxidants along with the known antioxidative, anti-inflammatory and phytoestrogenic stilbenoids in BPSP-supplemented diets leading to the observed inhibitory effectiveness on testosterone-mediated BPE is of merit.

Biosynthesis of peanut stilbenes, including resveratrol as the secondary metabolites, could be enhanced by subjecting the kernels to germination and wound-stress. Investigations of the bio-elicited peanut sprout powder (BPSP) addressed on characterization of the comprising stilbenes and effectiveness in longevity extension deserves intensive research. In this study, peanut kernels were subjected to germination and wound-stress in preparation of BPSP. The methanol extracts of BPSP were medium pressure liquid chromatographic (MPLC) fractionated and semi-preparative HPLC recovered and followed by instrumental identification and biological activity determinations of the isolated stilbenes. In longevity experiments, 16 female 11-mon-old BALB/c mice and both genders of 12-mon-old ICR mice were daily fed with BPSP supplemented diets at doses of 0, 0.1 and 0.5 g BPSP/kg bw for 750 and 762 days, respectively. Based on chemical characterization, enriched quantity of stilbenes in the BPSP up to ca. 1% (w/w) was detected. Two new stilbene compounds, namely, 4, 5’-dihydroxy-6’’-hydroxymethyl, 6’’-methylpyrano [2’’, 3’’: 3’, 4’] stilbene and 3, 4, 5’-trihydroxy-6’’, 6’’-dimethylpyrano [2’’, 3’’: 3’, 4’]stilbene along with 5 known stilbenes were isolated. The 7 stilbenes exhibited potent antioxidative and antiglycative activities and varied with structure-activity nature. Based on the resultant survival curves and average lifespans of both mouse models, basal diets supplemented with BPSP are effective to extend mouse longevity by a dose dependent manner. It is of merit to demonstrate that peanut kernels as a potent producer could be bio-elicited to biosynthesize a broad spectrum of bioactive stilbenes to prepare BPSP which is effective to extend mouse longevity as science-evidenced by the two long-term animal experiments.

Stereoselective synthesis of 2,3,3,4-tetrasubstituted oxetanes via intramolecular allyl or benzyl anion four-membered ring cyclization of vinylogous urethane derivatives is presented. The resulting products featuring a β-pyrrolidinyl ester at C3 were readily transformed into the corresponding 3-α,β-unsaturated ester substituted oxetanes by Cope elimination reactions.

Highly stereocontrolled total synthesis of dart frog indolizidine alkaloids (–)-167B, (–)-209I, and (–)-223A was accomplished, with a common tricyclic lactone intermediate as the starting compound, in overall yields of 17 %, 14 %, and 17 %, respectively. The C7–C8 bond of the 167B, without a C8 chiral substituent, was formed through ring closure metathesis followed by hydrogenation. In 209I and 223A, which have a C8 chiral substituent, highly substrate-controlled asymmetric radical cyclization was used to form the C7–C8 bond, and the correct stereochemistry of the C8 substituents was obtained in both molecules. Ethyl substituent at the C6 position of 223A was obtained with correct stereochemistry through asymmetric alkylation/epimerization sequences of the tricyclic lactone. Cleavage of the excess carbon on the C5 position of all three indolizidines was performed by using a Barton decarboxylation protocol. Reduction of the corresponding indolizidin-3-ones by LAH completed the total synthesis of (–)-167B, (–)-209I and (–)-223A.

In China, there is an urgent need for an efficient anaerobic digester to sustainably treat rice straw. In this study, a downward plug-flow anaerobic digester (DPAD) was designed in which the total working core is separated into three sections: an upper liquid zone, a lower liquid zone, and a solid-state bed (SSB) in the middle. A solid/liquid separation mechanism was designed to recirculate liquor and the discharged solid residue after complete digestion. The 70-L DPAD was run indoors for 100 d, time in which chopped rice straw (30 to 50 mm in length) was fed every 20 d. The digestion performance and biogas production were analysed to assess the feasibility for practice application. The results showed that the DPAD can control scum formation and offers a methane yield of 162.60 L/kg volatile solids, 21.1% higher than that of the control test. It was also found that straw was continuously and efficiently digested by the DPAD in 3 experimental stages. Methane production rates increased by 76.30%, 57.37%, and 13.33% on the second day compared to the first day, respectively, and then, all decreased as the substrate was gradually exhausted. Based on the results, it is clear that the DPAD is a promising solution for chopped straw digestion.

Mg/Al dissimilar materials were welded successfully by GTAW with SAlMg-1 and SAlMg-2 welding wire of Mg-Al system. The nice weld shape and free defects of joints are obtained. The test results indicated that continuous lamellar intermetallic compounds is not found The structure of Mg side in the fusion zone is composed of α-Mg solid solution+ β-Al12Mg17eutectic structure and precipitates β-A112lMg17on the grain boundary. The structure in the weld zone is mainly α-Mg solid solution + β-A112lMg17solid solutions. Mg and Al content are stable in the fusion zone of Mg side. However, in the weld zone of Mg side the Mg content is decreased gradually, and the Al content is increased that reaches a stable level in the weld zone of Al side. As a result, when Mg content in the wire can hold a proper level, the intermetallic compounds will be controlled effectively, and the performance of AZ31/7005 welding joint can be improved.

The main purpose of this article is to propose a linear model-based approach for improving the tracking performance of linear motors. In particular, P- and PI-controllers, augmented with a linear-model-based feedforward controller and disturbance observer (DOB), were utilized in this research. Experimental results show that the feedforward controller can substantially reduce the phase-delay problem resulting from the limitation of closed-loop bandwidth. In addition, the DOB can reject nonlinear behaviors to keep a motor-system close to our nominal linear model. Compared with the results of using P- and PI-controllers only, tracking errors were reduced from 4.44% to 0.67% of the desired trajectory. Therefore, the proposed method provides a solution for improving the tracking performance of linear motors.

Highly functionalized chiral furo-pyrrolizidinones containing contiguous quaternary centers were synthesized in moderate to good yields by treatment of various hexahydro-3,4-dioxa-8a-aza-as-indacen-2-ones with m-CPBA under basic conditions through a tandem Cope elimination/1,3-dipolar cycloaddition reaction sequence, followed by N-O cleavage and lactam ring cyclization.

This paper describes a convenient and efficient method for synthesizing chiral alcohol-substituted vinylogous urethanes, in which the double bond has E configuration was determined by single crystal X-ray analysis. In addition, we investigated the anti-aldol reactions of these chiral vinylogous urethane anions. The use of (1S,2R,4R)-1-(hydroxydiphenylmethyl)-7,7-dimethylbicyclo[2,2,1]-heptan-2-ol as a chiral auxiliary, provided the best enantioselectivities, and the resulting vinylogous urethane lactone could be used for the synthesis of (−)-prelactone B. A plausible mechanism for the generation of major enantiomeric isomer was discussed.

A new briarane-type diterpenoid, briaviolide Q (1), along with a known analogue, excavatolide Z (2), were obtained from a cultured octocoral Briareum violaceum. Details of the isolation and structure determination of briarane 1 from spectroscopic data are presented in this paper. In RAW264.7 cells, a macrophage-like murine cell line, briarane 1 was found to inhibit the protein expression of pro-inflammatory inducible nitric oxide synthase (iNOS) in cells stimulated by lipopolysaccharide (LPS).

The asymmetric [2,3]-Wittig rearrangement of the dienolates of various chiral β-pyrrolidinyl-γ-allyloxyl-α,β-unsaturated esters was investigated using different chiral secondary alcohol substitutions. When (1S,2R,4R)-2-hydroxy-7,7-dimethylbicyclo[2,2,1]heptane-1-carboxylic acid diisopropylamide was used as chiral auxiliary, it provided the best enantioselectivity in the rearrangement. When various γ-allyloxy substitutions underwent temperature and additive studies, 1,1-dimethylpropenoxy substitution was found to give the best enantioselectivity. The methodology was applied to the total synthesis of (+)-eldanolide.

Detection and surveillance of food commodities containing cyanide is a crucial issue of food safety. In this study, five strains of Pleurotus eryngii (P. eryngii) were grown in submerged culture of yeast malt broth (YMB) with the suspected production of HCN. A safety-warranted U-bent glass distilling collector with three enlarged bulbs on each arm was designed to recover the broth vapor. When AgNO(3) solution was used as an absorbent to interact with the vapor, a white precipitate was formed. The precipitate was isolated and identified as AgCN by FT-Raman spectroscopic analysis. When the absorbent was substituted by KOH, after evaporation to dryness, dissolved in D(2)O, and followed by (13)C-NMR analysis, a KCN spectrum was achieved. Formation of AgCN and KCN confirmed HCN production in the broth by P. eryngii. When a sodium picrate solution (1.4%) was used as an absorbent and various authentic KCN solutions were applied for distillation and followed by absorbance determination at 510 nm, a linear dose-dependent relationship was obtained and the procedure was applied for HCN quantification of the marketed P. eryngii mushrooms (fruiting body). As estimated, 67.3% of the products contained HCN less than 1.0 mg/kg, 17.3% between 1.0 and 2.0 mg/kg, and 15.4% higher than 2.0 mg/kg. When the mushrooms were sliced and cooked in water at 95 degrees C for 6 min, 89.1% of the original HCN was lost. When the P. eryngii strains were respectively grown by submerged cultivation in YMB or YMB supplemented with 2.5% glycine for 16 days, HCN content was slightly higher in the latter than in the former for each strain.

Dienolates of various γ-allyloxy substituted methyl β-pyrrolidinyl (E)-2-butenoate undergo a [2,3]-Wittig rearrangement to generate various 5-alkenyl-4-pyrrolidin-1-yl-5H-furan-2-one type compounds.

Zn-Al hydrotalcites were prepared by coprecipitation method with the Zn/Al molar ratio of 3:1, 2:1 and 1:1. Sodium dodecyl sulfate (SDS) and 2-carboxyethyl phenyl phosphinic acid (CEPPA) were adopted to modify hydrotalcite by coprecipitation method. The structure of Zn-Al hydrotalcites and the modified ones were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR) and scanning electron microscopy (SEM) coupled with energy dispersive spectrometer (EDS). XRD results indicated that the layered structure of Zn-Al hydrotalcites was influenced by the Zn/Al molar ratio. The Absorption peaks of Organic groups were observed in FT-IR Spectroscopy of SDS-LDH and CEPPA-LDH, which proved successfully synthesis of SDS modified LDH and CEPPA modified LDH. The SEM and EDS results confirmed the existence of SDS and CEPPA in the modified products, which are consistent with FT-IR results. The successful intercalation of SDS and CEPPA increased the interlayer space of LDH, which makes modified LDH promising and preferable as flame retardants in nanocomposites.