With the aim to discuss the similarities and differences of phytochemicals in
leaves collected from China (CML) and India (IML) in mind, comparative ultra-performance liquid chromatography coupled ...with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS) analysis was performed in this study. A screening analysis based on a UNIFI platform was first carried out to discuss the similarities. Next, untargeted metabolomic analysis based on multivariate statistical analysis was performed to discover the differences. As a result, a total of 122 components, containing 118 shared constituents, were characterized from CML and IML. The structure types included flavonoids, alkaloids, glyosides, organic acids and organic acid esters, iridoids, lignans, and steroids, etc. For CML, 121 compounds were characterized; among these, 18 potential biomarkers with higher contents enabled differentiation from IML. For IML, 119 compounds were characterized; among these, 12 potential biomarkers with higher contents enabled differentiation from CML. It could be concluded that both CML and IML are rich in phytochemicals and that CML is similar to IML in the kinds of the compounds it contains, except for the significant differences in the contents of some compounds. This comprehensive phytochemical profile study provides a basis for explaining the effect of different growth environments on secondary metabolites and exists as a reference for further research into or applications of CML in China.
Boron is an essential trace element with roles in growth, development, and physiological functions; however, its mechanism of action is still unclear. In this study, the regulatory roles of the ...PI3K/Akt signaling pathway on boron-induced changes in barrier function, proliferation, and apoptosis in rat intestinal epithelial cells were evaluated. Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein expression levels of PCNA were higher, while the proportions of cells in the G0/G1 and S phases, apoptosis rate, and caspase-3 mRNA and protein expression levels were lower in cells treated with 0.8 mmol/L boron than in control IEC-6 cells (P < 0.01 or P < 0.05). However, 40 mmol/L boron decreased ZO-1 and Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein levels of PCNA and increased the apoptosis rate and caspase-3 mRNA expression (P < 0.01 or P < 0.05). After specifically blocking PI3K and Akt signals (using LY294002 and MK-2206 2HCL), 0.8 mmol/L boron had no effects on Occludin, PCNA level, apoptosis rates, and caspase-3 levels (P < 0.05); however, the proliferation rate and PCNA levels decreased significantly (P < 0.01 or P < 0.05). The addition of 40 mmol/L boron did not affect ZO-1 and Occludin levels and did not affect the apoptosis rate or PCNA and caspase-3 levels. These results suggested that the PI3K/Akt signaling pathway mediates the effects of low-dose boron on IEC-6 cells.
In this study, near-liquidus squeeze casting AZ91D alloy was used to prepare differential support, and the microstructure and mechanical behavior under different applied pressure were investigated. ...Under the preset temperature, speed, and other process parameters, the effect of applied pressure on the microstructure and properties of formed parts was analyzed, and relevant mechanism was also discussed. The results showed that the ultimate tensile strength (UTS) and elongation (EL) of differential support can be improved by controlling real-time precision of the forming pressure. The dislocation density in the primary phase increased obviously with the pressure increasing from 80 MPa to 170 MPa, and even tangles appeared. When the applied pressure increased from 80 MPa to 140 MPa, the α-Mg grains were gradually refined, and the microstructure changed from rosette to globular shape. With increasing the applied pressure to 170 MPa, the grain could not be further refined. Similarly, its UTS and EL gradually increased with the applied pressure increasing from 80 MPa to 140 MPa. With increasing to 170 MPa, the UTS tended to be constant, but the EL gradually decreased. In other words, the UTS (229.2 MPa) and EL (3.43%) of the alloy reached the maximum when the applied pressure was 140 MPa, and the comprehensive mechanical properties were the best.
In this work, 25# valves alloy steel was selected as the experimental material for the new generation of low temperature valves steel. Effect of deep cryogenic treatment (DCT) time and cycle number ...on the microstructure evolution and mechanical/physical properties of 25# alloys steel were investigated and analyzed. Experimental results show that the microstructure for the tiny lath martensite after quenching, also lamellar martensite and retained austenite were obtained after DCT. At the same time, the retained austenite transformed into tiny lath martensite microstructure. Also, the smaller dispersion of M6C carbides were precipitated and distributed in grain boundaries and thin film retained austenite with an increase of DCT time and cycles as well as formation of stacking faults. The cryogenic processing has an obvious impact on the mechanical properties of materials. The strength of the material increases firstly and then sharply decreases with DCT time and cycles number, but the strain exhibits the opposite trend. The maximum strength is 1390 MPa, which is triple the original sample with a value of 441 MPa. Also, the hardness of the materials increases remarkably with a value of 52.6 HRC, enhancement of ∼28.9% and then decreases slightly with an increase of DCT time and cycles number. The fracture mechanism is typical cup - cone - shaped ductile fracture. After DCT, the linear expansion coefficient of the material gradually decreases and then table, which is satisfied with the cryogenic valves steel at low temperature service conditions.
•M6C carbides were precipitated and distributed in thin film retained austenite as well as formation of stacking faults.•The maximum strength is 1390 MPa, which are triple the original sample.•Hardness of the materials increases remarkably with a value of 52.6 HRC, enhancement of ∼28.9%.•The fracture mechanism is typical of cup - cone - shaped ductile fracture.
ABSTRACT
In order to study the effect of Hericium erinaceus polysaccharide (HEP) on the immune and antioxidation functions of immunosuppressed mice. The control group received distilled water orally ...and the model and experimental groups I, II, and III received 0, 80, 160, and 320 mg/kg HEP respectively for a fortnight after re-molding with cyoclphosphnalide (CTX). Compared with the control group, the secretion of IL-2, IL-4, and IFN-γ, the activity or content of T-AOC, T-SOD, and GSH-PX, and the expression of PCNA mRNA in the thymus and spleen were reduced in immunosuppressed mice (P < .05 or P < .01). Compared with immunosuppressed mice, the levels of IL-2, IFN-γ, and GSH-PX and the PCNA mRNA expression of spleen and thymus were increased (P < .05 or P < .01), and the microstructure were also obviously improved in the experimental group III. Overall, 320 mg/kg of HEP significantly improved the immune and antioxidant functions.
Graphical Abstract
Graphical Abstract
HEP can improve cytokine secretion by regulating antioxidant function and expression of apoptosis-related genes, thereby ameliorating tissue microstructure of thymus and spleen.
The eating and cooking qualities (ECQs) of rice (Oryza sativa L.) are key characteristics affecting variety adoption and market value. Starch viscosity profiles tested by a rapid visco analyzer (RVA) ...offer a direct measure of ECQs and represent the changes in viscosity associated with starch gelatinization. RVA profiles of rice are controlled by a complex genetic system and are also affected by the environment. Although Waxy (Wx) is the major gene controlling amylose content (AC) and ECQs, there are still other unknown genetic factors that affect ECQs.
Quantitative trait loci (QTLs) for starch paste viscosity in rice were analyzed using chromosome segment substitution lines (CSSLs) developed from the two cultivars 9311 and Nipponbare, which have same Wx-b allele. Thus, the effect of the major locus Wx was eliminated and the other locus associated with the RVA profile could be identified. QTLs for seven parameters of the starch RVA profile were tested over four years in Nanjing, China. A total of 310 QTLs were identified (from 1 to 55 QTLs per trait) and 136 QTLs were identified in more than one year. Among them, 6 QTLs were stalely detected in four years and 26 QTLs were detected in at least three years including 13 pleiotropic loci, controlling 2 to 6 RVA properties simultaneously. These stable QTL hotspots were co-located with several known starch synthesis-related genes (SSRGs). Sequence alignments showed that nucleotide and amino acid sequences of most SSRGs were different between the two parents. Finally, we detected stable QTLs associated with multiple starch viscosity traits near Wx itself, supporting the notion that additional QTLs near Wx control multiple characteristic values of starch viscosity.
By eliminating the contribution from the major locus Wx, multiple QTLs associated with the RVA profile of rice were identified, several of which were stably detected over four years. The complexity of the genetic basis of rice starch viscosity traits might be due to their pleiotropic effects and the multiple QTL hot spots. Minor QTLs controlling starch viscosity traits were identified by using the chromosome segment substitution strategy. Allele polymorphism might be the reason that QTLs controlling RVA profile characteristics were detected in some known SSRG regions.
Grain size in rice (
L.) shapes yield and quality, but the underlying molecular mechanism is not fully understood. We functionally characterized
(
), encoding a RING-type protein that localizes to ...the cytoplasm. The
mutant has fewer but enlarged grains compared to the wild type.
is mainly expressed in panicles and developing grains. Grain chalkiness was higher in the
mutant than in the wild type, short-chain amylopectin content was lower, middle-chain amylopectin content was higher, and appearance quality was worse. The amylose content and gel consistency of
were lower, and protein content was higher compared to the wild type. Rapid Visco Analyzer results showed that the texture of cooked
rice changed, and that the taste value of
was lower, making the eating and cooking quality of
worse than that of the wild type. We used
,
, and
monogenic and two-gene near-isogenic lines to study the effects of different combinations of genes affecting grain size on rice quality-related traits. Our results revealed additive effects for these three genes on grain quality. These findings enrich the genetic resources available for rice breeders.
Taxol is a rare secondary metabolite that accumulates considerably in
Taxus
species under salicylic acid (SA) and methyl jasmonate treatment. However, the molecular mechanism of its accumulation ...remains unclear. We investigated
TcWRKY33
, a nuclear-localized group I WRKY transcription factor, as an SA-responsive regulator of taxol biosynthesis. Overexpression and RNA interference of
TcWRKY33
confirmed that
TcWRKY33
regulates the expression of most taxol biosynthesis genes, especially
10-deacetylbaccatin III-10-O-acetyltransferase
(
DBAT
) and
taxadiene synthase
(
TASY
), which were considered as key enzymes in taxol biosynthesis. Transient overexpression of
TcWRKY33
in
Taxus chinensis
leaves resulted in increased taxol and 10-deacetylbaccatin accumulation by 1.20 and 2.16 times compared with the control, respectively. Furthermore,
TcWRKY33, DBAT
, and
TASY
were confirmed to respond positively to SA signals. These results suggested that
TcWRKY33
was the missing component of taxol biosynthesis that responds to SA. The sequence analysis identified two W-box motifs in the promoter of
DBAT
but not in the
TASY
. Yeast one-hybrid and dual-luciferase activity assays confirmed that
TcWRKY33
can bind to the two W-boxes in the promoter of
DBAT
, upregulating its expression level. Hence,
DBAT
is a direct target of
TcWRKY33
. Furthermore,
TcERF15
, encoding a
TASY
activator, also contains two W-boxes in its promoter. Yeast one-hybrid and dual-luciferase activity assays further confirmed that
TcWRKY33
can upregulate
TASY
expression through the activation of
TcERF15
. In summary,
TcWRKY33
transmits SA signals and positively regulates taxol biosynthesis genes in two ways: directly and through the activation of other activators. Therefore,
TcWRKY33
is an excellent candidate for genetically engineering regulation of taxol biosynthesis in
Taxus
plants.
Starch is the most important food energy source in cereals. Many of the known enzymes involved in starch biosynthesis are partially or entirely granule-associated in the endosperm. Studying the ...proteome of rice starch granules is critical for us to further understand the mechanisms underlying starch biosynthesis and packaging of starch granules in rice amyloplasts, consequently for the improvement of rice grain quality. In this article, we developed a protocol to purify starch granules from mature rice endosperm and verified the quality of purified starch granules by microscopy observations, I2 staining, and Western blot analyses. In addition, we found the phenol extraction method was superior to Tris-HCl buffer extraction method with respect to the efficiency in recovery of starch granule associated proteins. LC-MS/MS analysis showed identification of already known starch granule associated proteins with high confidence. Several proteins reported to be involved in starch synthesis in prior genetic studies in plants were also shown to be enriched with starch granules, either directly or indirectly, in our studies. In addition, our results suggested that a few additional candidate proteins may also be involved in starch synthesis. Furthermore, our results indicated that some starch synthesis pathway proteins are subject to protein acetylation modification. GO analysis and KEGG pathway enrichment analysis showed that the identified proteins were mainly located in plastids and involved in carbohydrate metabolism. This study substantially advances the understanding of the starch granule associated proteome in rice and post translational regulation of some starch granule associated proteins.
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