Synergistic action of novel maltohexaose-forming amylase and branching enzyme improves the enzymatic conversion of starch to specific maltooligosaccharide.

As attractive functional ingredients, maltooligosaccharides (MOS) are typically prepared by controlled enzymatic hydrolysis of starch. However, the random attack mode of amylase often leads to discrete product distribution, thereby reducing yields and purities. In this study, a novel glycoside hydrolase family 13 amylase AmyEs from marine myxobacteria Enhygromyxa salina was identified efficient maltohexaose (G6)-forming ability (40 %, w/w).

Dynamic changes and correlation analysis of microorganisms and flavonoids/ amino acids during white tea storage.

White tea stored for various times have different flavors. However, the mechanism of flavor conversion remains elusive. Flavonoids and amino acids are two typical flavor components in tea.

Characterization of a multi-domain exo-β-1,3-galactanase from Paenibacillus xylanexedens.

β-1,3-Galactanases selectively degrade β-1,3-galactan, thus it is an attractive enzyme technique to map high-galactan structure and prepare galactooligosaccharides. In this work, a gene encoding exo-β-1,3-galactanase (PxGal43) was screened form Paenibacillus xylanexedens, consisting of a GH43 domain, a CBM32 domain and α-L-arabinofuranosidase B (AbfB) domain. Using β-1,3-galactan (AG-II-P) as substrate, the recombined enzyme expressed in Escherichia coli BL21 (DE3) exhibited an optimal activity at pH 7.

Overexpression of PvBiP2 improved biomass yield and cadmium tolerance in switchgrass (Panicum virgatum L.).

Switchgrass (Panicum virgatum L.), the prime bioenergy feedstock crop, is one ideal candidate for phytoremediation of cadmium (Cd). The absorption of Cd imposes severe endoplasmic reticulum (ER)-stress in plants.

Yeast phospholipase D, Spo14, is not required for macroautophagy.

Autophagy-related gene (Atg) proteins are key players in autophagy. Some proteins that function in vesicle trafficking and lipid metabolism are also involved in autophagy. The SPO14 in yeast, which encodes phospholipase D (PLD), is involved in membrane trafficking and plays a vital role in sporulation during meiosis.

Highly Chemoselective [2+1] Annulation of α-Alkylidene Pyrazolones with α-Bromonitroalkenes: Synthesis of Pyrazolone-Based Vinylcyclopropanes and Computational Studies.

A highly chemoselective [2+1] annulation of α-alkylidene pyrazolones with α-bromonitroalkenes has been achieved under mild conditions. α-Alkylidene pyrazolones were unprecedentedly used as a C1 synthon to participate in annulation reactions, providing access to diverse vinylcyclopropane-based pyrazolone products. In addition, a spectrum of pharmaceutically interesting pyrazole-fused pyranone oximes could be rapidly obtained through a [2+1] annulation/rearrangement sequential process.

Enantio- and diastereoselective synthesis of spiropyrazolones via an organocatalytic [1 + 2 + 3] multicomponent reaction.

An asymmetric catalytic multicomponent reaction of malononitrile, benzaldehyde, and α-arylidene pyrazolinones to produce spiropyrazolones has been reported. The [1 + 2 + 3] multicomponent reaction was catalyzed by chiral cinchona alkaloids to provide spiropyrazolones in high yields, with excellent enantioselectivities and good diastereoselectivities. We also performed control experiments and proposed a plausible catalytic cycle based on the observed experimental results to explain the reaction process and stereoselectivity of the asymmetric multicomponent reaction.

Recent advances in the synthesis of C2-spiropseudoindoxyls.

Compared with the numerous reviews on the construction of C3 spirooxindoles, few reviews have examined the synthesis of structurally analogous C2-spiropseudoindoxyl derivatives. This scaffold has attracted substantial attention from synthetic chemists because of its relevance to medicinal chemistry. This review summarizes the recent progress in the synthesis of many heterocycle and carbocycle fused spiropseudoindoxyl compounds.

Chemo- and Stereoselective Cross Rauhut-Currier-Type Reaction of Tri-substituted Alkenes Containing Trifluoromethyl Groups.

A chemoselective cross Rauhut-Currier-type reaction has been developed involving a tri-substituted alkene (trifluoromethyl-containing acrylonitrile derivative) with a di- or tri-substituted alkene to yield tetra-substituted double bonds in RC-type products. This approach can support the synthesis of trifluoromethylated tetra-substituted olefins and synthetically important, structurally complex 3-allylic-type oxindole skeletons. The asymmetric version of this RC-type reaction can be realized by combining a Brønsted acid and Lewis base for bifunctional H-bonding-tertiary amine catalysis.

Efficient sample clean-up and online preconcentration for sensitive determination of melamine in milk samples by capillary electrophoresis with contactless conductivity detection.

Based on an efficient sample clean-up and field-amplified sample injection online preconcentration technique in capillary electrophoresis with contactless conductivity detection, a new analytical method for the sensitive determination of melamine in milk samples was established. In order to remove the complex matrix interference, which resulted in a serious problem during field-amplified sample injection, liquid-liquid extraction was utilized. As a result, liquid-liquid extraction provides excellent sample clean-up efficiency when ethyl acetate was used as organic extraction by adjusting the pH of the sample solution to 9.

A new Epichloe species with interspecific hybrid origins from Poa pratensis ssp. pratensis in Liyang, China.

We describe a new Epichloë species found in symbiosis with Poa pratensis ssp. pratensis in Liyang, China. Stromata characteristic of Epichloë spp.

[Characteristics of three spiroplasma isolates from honeybee (Apis mellifera)].

Objective: To investigate the kinds and characteristics of spiroplasma in honeybees, as well as to study the taxonomy and transmission of honeybee spiroplasma under natural conditions.

Methods: We examined the morphology of spiroplasma isolates by dark field and transmission electron microscopy and studied the biological characteristics by using conventional culture-dependent methods and molecular biology and serological methods.

Results: Three spiroplasma isolates were obtained from healthy Apis mellifera.

A new Neotyphodium species from Festuca parvigluma Steud. grown in China.

Neotyphodium species evolved from Epichloë species and are asexual, seedborne endophytes in many cool-season grasses. Here we propose a new species inhabiting Festuca parvigluma native to China. Morphology, host specificity and molecular phylogenetic evidence supported recognition of this new species.

Taxonomy of Neotyphodium endophytes of Chinese native Roegneria plants.

In this study we describe a new Neotyphodium species, Neotyphodium sinicum, found in natural symbiosis with asymptomatic Roegneria spp. (Elymus spp.) native to China.

A new stromata-producing Neotyphodium species symbiotic with clonal grass Calamagrostis epigeios (L.) Roth. grown in China.

We describe a new stromata-producing Neotyphodium species symbiotic with clonal Calamagrostis epigeios (L.) Roth. Stromata on the grass, 47.

[Isolation and biological characteristics of Spiroplasmas from flower surface].

Objective: To obtain the spiroplasma resources and investigate the characteristics of the spiroplasmas on the surface of flowers in China.

Methods: The spiroplasma morphology was examined by dark-field microscope and transmission electron microscopy. The biological characteristics of the spiroplasmas were investigated by using conventional culture-dependent method and phylogenetic analysis based on 16S rRNA gene and ITS (16-23S rDNA intergenic space) sequence comparisons.

A new species of Epichloë symbiotic with Chinese grasses.

Epichloë species are fungal symbionts (endophytes) of grasses, six European and four North American biological species in genus Epichloë have been described in previous researches. In this study we describe a new Epichloë species, Epichloë yangzii Li et Wang, found in natural symbioses with Roegneria kamoji native to China. We investigated the host specificity, morphology, interfertility tests and molecular phylogenetic evidences of this new species.