Four amino acids play an important role in the allergenicity of hemocyanin allergen.

To identify the key amino acids (AAs) affecting the allergenicity of hemocyanin (HC) allergens from Chinese mitten crabs, in this study, two epitopes, P1-SHFTGSKSNPEQR and P2-LSPGANTITR were employed and four potential key AAs (P1: F3 and N9 and P2: N6 and R10) were predicted. Mast cell and mouse models revealed that four mutants induced lower levels of immunoglobulin E (IgE) and Th2 type cytokines (15.47-49.

Molecular and allergenic properties of natural hemocyanin from Chinese mitten crab (Eriocheir sinensis).

Hemocyanin in crustaceans is an allergen for humans. However, little information was available on its molecular, structural and allergenic properties. In this study, the purified natural protein was identified as Eriocheir sinensis HC by LC-MS/MS, which was allergenic because its reaction with the serum IgE of crustacean patients.

Simultaneous Identification and Species Differentiation of Major Allergen Tropomyosin in Crustacean and Shellfish by Infrared Spectroscopic Chemometrics.

To solve the lack of rapid and accurate methods for allergen identification and traceability, an infrared spectroscopic chemometric analytical model (IR-CAM) was established by combining infrared spectroscopy with principal component and cluster analysis. By comparing the second derivative infrared (SD-IR) spectra of 5 proteins and 14 crustaceans and shellfish tropomyosin (TM), 8 shared peaks and unique fingerprint peaks in the amide III region were found for crabs, shrimps, and shellfish. Based on the unique fingerprint peaks coexisting with shared peaks, allergen TM in crustaceans and shellfish could be identified within 10 min (cf.

Engineering yeast for high-level production of diterpenoid sclareol.

The diterpenoid sclareol is an industrially important precursor for alternative sustainable supply of ambergris. However, its current production from plant extraction is neither economical nor environmental-friendly, since it requires laborious and cost-intensive purification procedures and plants cultivation is susceptible to environmental factors. Engineering cell factories for bio-manufacturing can enable sustainable production of natural products.

Changes in protease activity during fermentation of fish sauce and their correlation with antioxidant activity.

Background: Antioxidant activity has been found in fermented fish sauce. In this experiment, the properties of endogenous protease and antioxidant activity were studied in anchovy sauce during fermentation. The correlation between protease activity and antioxidant activity in fermented anchovy sauce was analyzed using the partial least squares (PLS) method.

Changes in taste substances during fermentation of fish sauce and the correlation with protease activity.

Anchovy sauce shows different taste profiles under different fermentation time. The change rules of free amino acids was measured by amino acid analyzer, and other taste substances, such as nucleotides and organic acids in anchovy sauce under different fermentation time were also investigated. Moreover, the correlation between protease activity and taste substances in anchovy sauce fermentation was analyzed by orthogonal partial least squares.

Characterization and structure-activity relationship of novel umami peptides isolated from Thai fish sauce.

Fish sauce has a prominent umami flavor. In this study, umami peptides were isolated, purified and identified from Thai fish sauce, and their structure-activity relationships were analyzed. Six novel umami peptides were characterized and verified by using sensory evaluation and a electronic tongue.

Identification, taste characterization and molecular docking study of novel umami peptides from the Chinese anchovy sauce.

Background: Fish sauce has a subtle flavor with prominent umami and salty taste, and is accompanied by a certain sweetness and bitterness. In order to identify a wider range of umami peptides, Chinese southern and northern anchovy sauce were selected for the study.

Results: Seventeen peptides were obtained by separation and purification, and their taste activity was predicted.

Leaching and retention of dissolved metals in particulate loaded pervious concrete columns.

This study examined metal leaching and retention in pervious concrete with or without embedded particulate matter. Particulate matter was collected from an adjacent parking lot and from a nearby parking garage as examples of weathered and un-weathered particulate matter. Particle size distributions were similar, but metal content was 3-35-fold higher and organic matter content was 3-fold higher in the parking garage particulate matter compared to the parking lot particulate matter.

Functional and structural properties of a novel cellulosome-like multienzyme complex: efficient glycoside hydrolysis of water-insoluble 7-xylosyl-10-deacetylpaclitaxel.

Cellulosome is a kind of multienzyme complex that displays high activity, selectivity, and stability. Here, we report a novel, non-cellulolytic, cellulosome-like multienzyme complex that produced by the Cellulosimicrobium cellulans wild-type strain F16 isolated from soil microflora. This multienzyme complex, with excellent catalytic efficiency of kcat 13.

Self-sustained reduction of multiple metals in a microbial fuel cell-microbial electrolysis cell hybrid system.

A self-sustained hybrid bioelectrochemical system consisting of microbial fuel cell (MFC) and microbial electrolysis cell (MEC) was developed to reduce multiple metals simultaneously by utilizing different reaction potentials. Three heavy metals representing spontaneous reaction (chromium, Cr) and unspontaneous reaction (lead, Pb and nickel, Ni) were selected in this batch-mode study. The maximum power density of the MFC achieved 189.

Enzymatic hydrolysis of 7-xylosyltaxanes by an extracellular xylosidase from Cellulosimicrobium cellulans.

Objectives: To find extracellular biocatalysts that can specifically and efficiently remove the C-7 xylosyl group from 7-xylosyltaxanes.

Results: A Cellulosimicrobium cellulans strain F16 that can remove the C-7 xylosyl group from 7-xylosyltaxanes was isolated from the root soil of an old Taxus yunnanensis tree. Using corn cob as sole carbon source, the maximum 7-xylosyl-10-deacetylpaclitaxel β-xylosidase activity of 9.

Size characterization of dissolved metals and organic matter in source waters to streams in developed landscapes.

Individual and mixed water samples from wastewater treatment plant effluents, stormwater runoff, streams from developed areas were characterized with respect to organic matter concentration and spectral properties and metal concentration and size distribution. In addition, asymmetric flow-field flow fractionation coupled to inductively coupled plasma mass spectrometry was used to measure concentration, size distribution and association of metals in the colloidal size range. Results reveal that Fe, Cu, Zn and Pb in the colloidal size range were mainly associated with the less than 5 nm, or less than 10 kDa size range.

[Industrial preparative chromatography purification of 10-deacetylpaclitaxel, the enzymatic product of 7-xylosyl-10-deacetylpaclitaxel].

A scheme for industrial preparative chromatography purification of 10-deacetylpaclitaxel (10-DAP), the semi-synthesized precursor of anticancer drug paclitaxel was developed. 7-Xylosyl-10-deacetylpaclitaxel (10-DAXP) is the most abundant constitute in the needles of Taxus Chinensis, a specific yew species distributed in China. 10-DAXP has been recognized as a good material to convert into 10-DAP, the most ideal precursor of paclitaxel.

Rapid qualitative and quantitative determination of seven valuable taxanes from various Taxus species by UFLC-ESI-MS and UFLC-DAD.

The distribution and level of yew constituents vary with species and tissues. In this study, a rapid and valid method incorporating ultra-fast liquid chromatography (UFLC) with MS and UV detection was developed for simultaneous determination of paclitaxel and its six semisynthesis precursors in needles and hair roots from various Taxus species. All target analytes could be identified by comparing their retention times as well as UV and MS spectra with authentic standards, while seven valuable taxanes in botanical samples can be rapidly determined by UFLC-DAD with excellent sensitivity.

Effective dechlorination of HCB by nanoscale Cu/Fe particles.

We previously reported that microscale Cu/Fe bimetal could be used for the dechlorination of hexachlorobenzene (HCB), a representative polychlorinated persistent organic pollutant (POPs). But slow reduction rate and rather incomplete dechlorination were reached. In this study, HCB dechlorination by nanoscale Fe and Cu/Fe was evaluated.

Quantitative structure-retention relationship studies for taxanes including epimers and isomeric metabolites in ultra fast liquid chromatography.

Seven pairs of epimers and one pair of isomeric metabolites of taxanes, each pair of which have similar structures but different retention behaviors, together with additional 13 taxanes with different substitutions were chosen to investigate the quantitative structure-retention relationship (QSRR) of taxanes in ultra fast liquid chromatography (UFLC). Monte Carlo variable selection (MCVS) method was adopted to choose descriptors. The selected four descriptors were used to build QSRR model with multi-linear regression (MLR) and artificial neural network (ANN) modeling techniques.

Acceptor specificity and transfer efficiency of a beta-glycosidase from the Chinese white jade snail.

The acceptor specificity and transfer potential of a beta-D-glycosidase (G I), which had been purified from the China white jade snail, were further investigated by using various sugars as acceptors. G I had broad monosaccharide acceptor specificity for its transglycosylation activity. More specifically, it efficiently catalyzed the transfer of the beta-D-fucosyl, beta-D-glucosyl or beta-D-galactosyl moiety from the corresponding p-nitrophenyl-beta-D-glycopyranosides to various monosaccharides.

Deoxynojirimycin enhanced the transglycosylation activity of a glycosidase from the China white jade snail.

A beta-D-glycosidase (G I) from the China white jade snail showed non-Michaelis-Menten mode in catalyzing the reaction using pNPGlu and pNPFuc as the substrate and monitoring the released pNP. We determined quantitatively both the transglycosidic and hydrolytic products of pNPGlu and pNPFuc solvolysis for the detailed kinetic analysis on G I-catalyzed hydrolysis and transglycosylation reaction. The inhibition kinetic studies using deoxynojirimycin (DNJ) and butanol as inhibitors were preceded.

[Purification and characterization of a beta-D-xylosidase from Leifsonia shinshuensis DICP 16].

A beta-D-xylosidase from Leifsonia shinshuensis DICP 16 was purified to apparent homogeneity using a combination of ammonium sulfate precipitation, DE 52 anion-exchange, Q-Sepharose Fast Flow anion-exchange, Toyopearl Butyl 650C hydrophobic-interaction and Sephacryl S-300 HR gel-permeation chromatography. The purified xylosidase consisted of two same subunits and had the relative molecular weight of 180 kD as determined by SDS-PAGE and gel-permeation chromatography. The maximal beta-D-xylosidase activity occurred at 55 degrees C and pH 7.

Profiling of yew hair roots from various species using ultra-performance liquid chromatography/electrospray ionization mass spectrometry.

An efficient and sensitive profiling approach to complex yew samples was developed using ultra-performance liquid chromatography/electrospray ionization mass spectrometry (UPLC/ESI-MS). The UPLC-based method displayed short analytical time and improved peak capability, as well as high sensitivity. The appropriate in-source collision-induced dissociation (CID) energy was employed to produce informative characteristic ions which could be used for stereochemical and sub-structural assignment of yew constituents.

Chemotaxonomic study of medicinal Taxus species with fingerprint and multivariate analysis.

Species delimitation in Taxus has been controversial and it is very difficult to distinguish yew materials by their morphological characters. In this paper, a valid HPLC fingerprinting method coupled with multivariate analysis was used to define a framework for Taxus species identification and classification. Fingerprint-based similarity was employed for a chemotaxonomic study by hierarchical clustering analysis (HCA) and principal component analysis (PCA).