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Iron deficiency is the most common nutritional disorder, affecting over 30% of the world’s human population. The primary method used to alleviate this problem is nutrient biofortification of crops so as to improve the iron content and its availability in food sources. The over-expression of ferritin is an effective method to increase iron concentration in transgenic crops. For the research reported herein, sickle alfalfa (Medicago falcata L.) ferritin was transformed into wheat driven by the seed-storage protein glutelin GluB-1 gene promoter. The integration of ferritin into the wheat was assessed by PCR, RT-PCR and Western blotting. The concentration of certain minerals in the transgenic wheat grain was determined by inductively coupled plasma-atomic emission spectrometry, the results showed that grain Fe and Zn concentration of transgenic wheat increased by 73% and 44% compared to nontransformed wheat, respectively. However, grain Cu and Cd concentration of transgenic wheat grain decreased significantly in comparison with non-transformed wheat. The results suggest that the over-expression of sickle alfalfa ferritin, controlled by the seed-storage protein glutelin GluB-1 gene promoter, increases the grain Fe and Zn concentration, but also affects the homeostasis of other minerals in transgenic wheat grain.
Red coleoptile is an easily observed agronomic trait of wheat and has been extensively studied. However, the molecular mechanism of this trait has not yet been revealed. In this study, the MYB gene TaMYB-D1 was isolated from the wheat cultivar ‘Gy115’, which possesses red coleoptiles. This gene resided at the short arm of the homoelogous group 7 chromosomes. TaMYB-D1 was the only gene expressed in the coleoptiles of ‘Gy115’ and was not expressed in ‘Opata’ and ‘CS’, which have uncoloured coleoptiles. Phylogenetic analysis placed TaMYB-D1 very close to ZmC1 and other MYB proteins regulating anthocyanin biosynthesis. The encoded protein of TaMYB-D1 had an integrated DNA binding domain of 102 amino acids and a transcription domain with 42 amino acids, similar to the structure of ZmC1. Transient expression analysis in onion epidermal cells showed that TaMYB-D1 was located at the plant nucleus, which suggested its role as a transcription factor. The expression of TaMYB-D1 was accompanied with the expression of TaDFR and anthocyanin biosynthesis in the development of the coleoptile of ‘Gy115’. Transient expression analysis showed that only TaMYB-D1 induced a few ‘Opata’ coleoptile cells to synthesize anthocyanin in light, and the gene also induced a colour change to red in many cells with the help of ZmR. All of these results suggested TaMYB-D1 as the candidate gene for the red coleoptile trait of ‘Gy115’.
High-yield common buckwheat ‘cv. Fengtian 1’ (FT1) and tartary buckwheat ‘cv. Jingqiao 2’ (JQ2) were selected to investigate the characteristics of the grain-filling process and starch accumulation of high-yield buckwheat. FT1 had an average yield that was 43.0% higher than that of the control ‘cv. Tongliaobendixiaoli’ (TLBDXL) in two growing seasons, while JQ2 had an average yield that was 27.3% higher than that of the control ‘cv. Chuanqiao 2’ (CQ2). The Richards equation was utilized to evaluate the grain-filling process of buckwheat. Both FT1 and JQ2 showed higher values of initial growth power and final grain weight and longer linear increase phase, compared with respective control. These values suggest that the higher initial increasing rate and the longer active growth period during grain filling play important roles to increase buckwheat yield. Similar patterns of starch, amylose and amylopectin accumulation were detected in common buckwheat, leading to similar concentration of each constituent at maturity in FT1 and TLBDXL. Tartary buckwheat showed an increasing accumulation pattern of amylose in developing seeds, which differed from that of starch and amylopectin. This pattern led to a significant difference of the concentrations of amylose and amylopectin at maturity between JQ2 and CQ2, the mechanisms of which remained unclear. Nevertheless, both FT1 and JQ2 showed increased starch, amylose, and amylopectin accumulation during the physiological maturity of grains. The results suggest that prolonging the active grain-filling period to increase carbohydrate partitioning from source to seed sink can be an effective strategy to improve buckwheat yield.
New high-molecular-weight glutenin (HMW glutenin) sequences isolated from six Psathyrostachys juncea accessions by thermal asymmetric interlaced PCR differ from previous sequences from this species. They showed novel modifications in all of the structural domains, with unique C-terminal residues, and their N-terminal lengths were the longest among the HMW glutenins reported to date. In their repetitive domains, there were three repeatable motif units: 13-residue [GYWH(/I/Y)YT(/Q)S(/T)VTSPQQ], hexapeptide (PGQGQQ), and tetrapeptide (ITVS). The 13-residue repeats were restricted to the current sequences, while the tetrapeptides were only shared by D-hordein and the current sequences. However, these sequences were not expressed as normal HMW glutenin proteins because an in-frame stop codon located in the C-termini interrupted the intact open reading frames. A phylogenetic analysis supported different origins of the P. juncea HMW glutenin sequences than that revealed by a previous study. The current sequences showed a close relationship with D-hordein but appeared to be more primitive.
Abstract
As research advances, it is generally acknowledged that non-Saccharomyces yeast contribute to the addition of aromatic compounds during mead fermentation. In this experiment, eight different non-Saccharomyces strains and Saccharomyces cerevisiae co-fermentation, their aroma composition, and basic physicochemical parameters were investigated. More than 30 compounds with favourable impact were discovered using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Co-fermentation of non-Saccharomyces spp. and S. cerevisiae can affect the concentration of volatile compounds, so that the mead presents different aroma characteristics. Co-fermented meads of Wickerhamomyces anomalus strains and S. cerevisiae (Wa 27-Sc and Wa 5-Sc) had higher alcohol, acids, aldehyde, and ester concentrations than those fermented with S. cerevisiae alone. In terms of taste, Wa 27-Sc was superior to Wa 5-Sc. Overall, the Wa 27-Sc received the highest score for its strong secondary aroma and good mouthfeel. The results show that the W. anomalus Wa 27 strain has a good potential to produce high quality mead.
A method was developed for the preparative separation of two alkaloids from the crude extract of the radix of Rauvolfia verticillata (Lour.) Baill. in a single run. The two-phase solvent system composed of petroleum ether–ethyl acetate–methanol–water (5:5:2:8, v/v), where triethylamine (40 mmol/L) was added to the upper organic phase as the stationary phase and hydrochloric acid (10 mmol/L) was added to the lower aqueous phase as the mobile phase, was selected for this separation by pH-zone-refining counter-current chromatography (PZRCCC). For the preparative separation, the apparatus was rotated at a speed 850 rpm, while the mobile phase was pumped into the column at 2 mL/min. As a result, 112 mg of reserpine and 21 mg of yohimbine were obtained from 3 g of crude extract in a single run. The analysis of the isolated compounds was determined by high-performance liquid chromatography (HPLC) at 230 nm with purities of over 91.0%, and the chemical identification was carried out by the data of electrospray ionization–mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) spectroscopy. The technique introduced in this paper is an efficient method for preparative separation of reserpine and yohimbine from devil pepper radix. It will be beneficial to utilize medicinal materials and also useful for the separation, purification, and pharmacological study of Chinese herbal ingredients.
Compound danshen preparations (CDPs) are used clinically for the treatment of cardiovascular and cerebrovascular diseases. By using the quantitative analysis of multi-components by single-marker (QAMS) method, sixteen compounds (danshensu, protocatechuic acid, protocatechuicaldehyde, caffeic acid, rosmarinic acid, lithospermic acid, notoginsenoside R1, salvianolic acid B, ginsenoside Rg1, ginsenoside Re, salvianolic acid A, salvianolic acid C, ginsenoside Rb1, ginsenoside Rd, cryptotanshinone, and tanshinone IIA were quantified on an ACQUITY ultraperformance liquid chromatography (UPLC) HSS T3 column (2.1 × 100 mm, 1.8 μm) with the mobile phase consisting of 0.1% formic acid aqueous solution (A) and acetonitrile (B) using a gradient elution at the flow rate of 0.30 mL/min in 30 min at 30°C, which was also validated by UPLC-diode array detection (DAD) and UPLC-electrospray ionization multistage/mass spectrometry (ESI-MS/MS) for assuring the feasibility and accuracy. Tested by robustness experiment under slightly changeable conditions, the stability of relative correction factor (RCF) proved to be stable, with RSDs below 5.69%, except for notoginsenoside R1 with relative standard deviation (RSD) 7.83%. This reliable and convenient QAMS method resolved the problem of standard substance insufficiency and improved the quality assessment of preparations consisting of complex compounds with different chemical structures, such as CDPs.
Abstract
The effect of mechanical alloying on Zn-Sb alloy system is investigated with X-ray diffraction (XRD), laser grain size analysis and differential scanning calorimetry (DSC) respectively. The results of laser particle size analysis shows that the particle size decreases with increasing of the grinding time between 0 and 24 h. XRD and DSC results indicate that longer the grinding time of Zn-Sb is, the more content of Zn4Sb3 become in the product in this process.
Abstract
Background and aims
Previous evidence has indicated that problematic social media use (PSMU) is characterized by an attentional bias to social media icons (such as Facebook icons), but not to social webpages (such as Facebook webpages). They suggest that there may be other factors influencing attentional bias like fear of missing out (FoMO). But it remains unclear how FoMO moderates attentional bias in PSMU. This study aims to investigate whether PSMU show attentional bias for stimuli associated with social media, and how FoMO moderates on attentional bias among PSMU through experimental methods.
Methods
Based on the Interaction of Person-Affect-Cognition-Execution (I-PACE) model, this study explored mechanisms of attentional bias to social media icons (such as WeChat) related to PSMU and further examined the role of FoMO in this relationship. Specifically, attentional bias patterns to social media icons of 62 participants (31 PSMU and 31 control group) were explored during a dot-probe paradigm combined with eye-tracking in Experiment 1, and attentional bias patterns to social media icons of another 61 individuals with PSMU with different FoMO levels was explored during a dot-probe paradigm combined with eye-tracking in Experiment 2.
Results
Results revealed that individuals with PSMU had an attentional bias toward social media icons, demonstrated by attentional maintenance, and such bias such bias was moderated by FoMO negatively, demonstrated by attentional vigilance and maintenance in PSMU/high FoMO.
Conclusion
These results suggest that attentional bias is a common mechanism associated with PSMU, and FoMO is a key factor on the development of PSMU.
Abstract
Soluble dietary fibre (SDF) is well recognised for its remarkable effectiveness in promoting human health. This study utilised response surface methodology to evaluate the optimal conditions required to extract SDF (U-SDF) from Lentinula edodes via the ultrasonic-assisted hot-water method, and evaluated the hypolipidemic effects and anti-inflammatory effects of U-SDF. The optimal extraction conditions for U-SDF were ultrasonic power of 182 W, extraction time of 2 h, extraction temperature of 81 °C, and solid-liquid ratio of 1:24 (g mL−1). Under these conditions, the extraction rate of U-SDF reached 8.08%. U-SDF treatment significantly improved liver and kidney indices in diabetic mice, markedly reduced the levels of plasma triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and significantly increased the level of high-density lipoprotein-cholesterol (HDL-C) in a dose-dependent manner. U-SDF also improved adipose tissue injury in diabetic mice, significantly decreased the levels of cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α), and alleviated inflammation of the abdominal aorta. In conclusion, U-SDF from L. edodes is an excellent source of dietary fibres, which exhibit good hypolipidemic and anti-inflammatory activities, suggesting potential applications as a functional additive in diverse food products.
