Acylated anthocyanins from Dendrobium officinale Kimura & Migo: Structural characteristics, antioxidant and hypoglycemic activities.

Dendrobium officinale Kimura & Migo (D. officinale) has been widely used as Chinese medicine and functional food. In present study, the structural characteristics of anthocyanins in D. officinale were investigated by ultra-performance liquid chromatography with diode array detector (UPLC-DAD) and ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS/MS). Totally, 14 anthocyanins were detected and identified, and 13 of them were first reported in D. officinale. Results showed that the vast majority of anthocyanins had multi-glycosylated cyanidin core, with variable acylation pattern mainly comprising phenolic acids. The composition and content of anthocyanins in D. officinale stems with different cultivation modes and years have been compared. The anthocyanins showed potent antioxidant activity in terms of radicals scavenging capacity and reducing power, as well as superior α-amylase and α-glucosidase inhibitory activity. The results provided a complete profile of anthocyanins in D. officinale and laid a foundation for further utilizing them as functional foods.

Structural characteristics, functional properties, antioxidant and hypoglycemic activities of pectins from feijoa (Acca sellowiana) peel.

The structure characteristics, functional properties, antioxidant and hypoglycemic activities of pectins extracted from feijoa peel with water (FP-W), acid (FP-A) and alkali (FP-B) were investigated. Results showed that the feijoa peel pectins (FPs) were mainly composed of galacturonic acid, arabinose, galactose and rhamnose. FP-W and FP-A had higher proportion of homogalacturonan domain, degree of esterification and molecular weight (for main component) than FP-B; FP-B owned the highest yield, protein and polyphenol contents. FP-W had a compact and smooth surface morphology unlike FP-A and FP-B. FP-W and FP-A had better thermal stability than FP-B. The rheological analysis suggested that the FPs exhibited pseudoplastic fluid behavior, and the elastic characteristics were dominant. Results showed that FP-W and FP-B had superior antioxidant and hypoglycemic activities than FP-A. According to correlation analysis, monosaccharide composition, sugar ratios and degree of acetylation were chief factors affecting the functional properties, antioxidant and hypoglycemic activities of the FPs.

Determination of Biogenic Amines in Wine from Chinese Markets Using Ion Chromatography-Tandem Mass Spectrometry.

A method for the determination of nine biogenic amines (BAs) in wine was established using ion chromatography-tandem mass spectrometry (IC-MS/MS) without derivatization. BAs were separated by a cation exchange column (IonPac CG17, 50 mm × 4 mm, 7 µm) with a gradient aqueous formic acid elution. Good linearity was obtained for nine BAs with coefficients of determination (R2) > 0.9972 within the range of 0.01-50 mg/L. The limits of detection and quantification were within the ranges of 0.6-40 µg/L and 2.0-135 µg/L, respectively, with the exception of spermine (SPM). The recoveries were demonstrated within the range of 82.6-103.0%, with relative standard deviations (RSDs) of less than 4.2%. This simple method featuring excellent sensitivity and selectivity was suitable for the quantification of BAs in wines. The occurrence of BAs in 236 wine samples that are commercially available in China was determined. The BA levels in wines of different geographical origins varied significantly. The acute dietary exposure assessment of BAs was carried out by calculating the estimated short-term intake (ESTI) and comparing the acute reference dose (ARfD) specified by the European Food Safety Authority (EFSA). Results showed that the exposure to histamine (HIS) and tyramine (TYR) via the consumption of wines was much lower than the recommended ARfD level for healthy individuals. However, exposure could lead to symptoms in susceptible individuals. These results provided basic data regarding the occurrence and risk of BAs in wines for wine production, health guidance and consumer safety.

Can the apparent transverse relaxation rate (R2*) evaluate the efficacy of concurrent chemoradiotherapy in locally advanced nasopharyngeal carcinoma? a preliminary experience.

BACKGROUND: The use of the apparent transverse relaxation rate (R2*) in nasopharyngeal carcinoma (NPC) has not been previously reported in the literature. The aim of this study was to investigate the role of the R2* value in evaluating response to concurrent chemoradiotherapy (CCRT) in patients with NPC. METHODS: Forty-one patients with locoregionally advanced NPC confirmed by pathology were examined by blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) before and after CCRT, and conventional MRI was performed 3 months after the completion of CCRT. All patients were divided into a responding group (RG) and a nonresponding group (NRG), according to MRI findings 3 months after the end of treatment. The R2* values before (R2*preT) and after (R2*postT) CCRT and the ΔR2* (ΔR2*=R2*postT - R2*preT) were calculated in the tumor. RESULTS: Among the 41 patients, 26 were in the RG and 15 were in the NRG. There was no statistical difference in the R2*preT between RG and NRG (P = 0.307); however, there were significant differences in R2*postT and ΔR2* (P < 0.001). The area under the curve of R2*postT and ΔR2* for predicting the therapeutic response of NPC was 0.897 and 0.954, respectively, with cutoff values of 40.95 and 5.50 Hz, respectively. CONCLUSION: The R2* value can be used as a potential imaging indicator to evaluate the therapeutic response of locoregionally advanced NPC.

Effects of Light Shading, Fertilization, and Cultivar Type on the Stable Isotope Distribution of Hybrid Rice.

The effect of fertilizer supply and light intensity on the distribution of elemental contents (%C and %N) and light stable isotopes (C, N, H, and O) in different rice fractions (rice husk, brown rice, and polished rice) of two hybrid rice cultivars (maintainer lines You-1B and Zhong-9B) were investigated. Significant variations were observed for δ13C (-31.3 to -28.3‱), δ15N (2.4 to 2.7‱), δ2H (-125.7 to -84.7‱), and δ18O (15.1‱ to 23.7‱) values in different rice fractions among different cultivars. Fertilizer treatments showed a strong association with %N, δ15N, δ2H, and δ18O values while it did not impart any significant variation for the %C and δ13C values. Light intensity levels also showed a significant influence on the isotopic values of different rice fractions. The δ13C values showed a positive correlation with irradiance. The δ2H and δ15N values decreased with an increase in the irradiance. The light intensity levels did not show any significant change for δ18O values in rice fractions. Multivariate ANOVA showed a significant interaction effect of different factors (light intensity, fertilizer concentration, and rice variety) on the isotopic composition of rice fractions. It is concluded that all environmental and cultivation factors mentioned above significantly influenced the isotopic values and should be considered when addressing the authenticity and origin of rice. Furthermore, care should be taken when selecting rice fractions for traceability and authenticity studies since isotopic signatures vary considerably among different rice fractions.

Chemical structure and antioxidant activity of a neutral polysaccharide from Asteris Radix et Rhizoma.

Asteris Radix et Rhizoma (AR) has been widely used as a herbal medicine for treating various symptoms and possesses a number of bioactivities. A neutral polysaccharide ARP-1 was isolated from AR with weight-average molecular weight of 214 kDa. The heteropolysaccharide ARP-1 was composed of fucose, arabinose, galactose, glucose and mannose with a molar ratio of 0.40:14.25:10.22:1.06:0.41. Linkage and NMR analysis showed that ARP-1 had a backbone containing →3,6)-ß-d-Galp-(1→ and →6)-ß-d-Galp-(1 â†’ residues, and oligosaccharide side chains containing Araf and Galp units were attached to the backbone at C-3 of →3,6)-ß-d-Galp-(1 â†’ residues. Antioxidant activity assays showed that ARP-1 exhibited potent antioxidant activities, including ABTS, hydroxy and DPPH radicals scavenging and reducing power. Besides, ARP-1 decreased the production of ROS and MDA, and improved the activities of SOD, which resulted in the protection of PC12 cells against H2O2-induced oxidative stress. The findings indicated that ARP-1 might be used as a potential natural antioxidant.

Changes in Physicochemical Properties, Volatile Profiles, and Antioxidant Activities of Black Apple During High-Temperature Fermentation Processing.

Black apple is a new elaborated product obtained from whole fresh apple through fermentation at controlled high temperature (60~90°C) and humidity (relative humidity of 50~90%). The appearance, color, texture, and taste of black apple changed dramatically compared with those of fresh apple. In this study, changes in the physicochemical and phytochemical properties, volatile profiles, and antioxidant capacity of apple during the fermentation process were investigated. Results showed that the browning intensity and color difference increased continuously during the whole 65-day fermentation process (p < 0.05). Sugars decreased in the whole fermentation process (p < 0.05), whereas the contents of organic acids increased first and then decreased with prolonged 35 days of fermentation (p < 0.05). Total polyphenol content of black apple showed an increase of 1.5-fold as that of fresh apple, whereas 12 common polyphenolic compounds present in fresh apple decreased dramatically in the whole fermentation process (p < 0.05). The analysis of flavor volatiles showed that high-temperature fermentation decreased the levels of alcohols and esters and resulted in the formation of furanic and pyranic compounds, which are the main products of Maillard reaction (MR). Antioxidant activities of black apple were enhanced compared with those of fresh apple, and results indicated that the enhancement of antioxidant activities was related to the polyphenols and products of MR.

Three genetic systems controlling growth, development and productivity of rice (Oryza sativa L.): a reevaluation of the 'Green Revolution'.

The Green Revolution (GR-I) included worldwide adoption of semi-dwarf rice cultivars (SRCs) with mutant alleles at GA20ox2 or SD1 encoding gibberellin 20-oxidase. Two series of experiments were conducted to characterize the pleiotropic effects of SD1 and its relationships with large numbers of QTLs affecting rice growth, development and productivity. The pleiotropic effects of SD1 in the IR64 genetic background for increased height, root length/mass and grain weight, and for reduced spikelet fertility and delayed heading were first demonstrated using large populations derived from near isogenic IR64 lines of SD1. In the second set of experiments, QTLs controlling nine growth and yield traits were characterized using a new molecular quantitative genetics model and the phenotypic data of the well-known IR64/Azucena DH population evaluated across 11 environments, which revealed three genetic systems: the SD1-mediated, SD1-repressed and SD1-independent pathways that control rice growth, development and productivity. The SD1-mediated system comprised 43 functional genetic units (FGUs) controlled by GA. The SD1-repressed system was the alternative one comprising 38 FGUs that were only expressed in the mutant sd1 backgrounds. The SD1-independent one comprised 64 FGUs that were independent of SD1. GR-I resulted from the overall differences between the former two systems in the three aspects: (1) trait/environment-specific contributions; (2) distribution of favorable alleles for increased productivity in the parents; and (3) different responses to (fertilizer) inputs. Our results suggest that at 71.4 % of the detected loci, a QTL resulted from the difference between a functional allele and a loss-of-function mutant, whereas at the remaining 28.6 % of loci, from two functional alleles with differentiated effects. Our results suggest two general strategies to achieve GR-II (1) by further exploiting the genetic potential of the SD1-repressed and SD1-independent pathways and (2) by restoring the SD1-mediated pathways, or 'back to the nature' to fully exploit the genetic diversity of those loci in the SD1-mediated pathways which are virtually inaccessible to most rice-breeding programs worldwide that are exclusively based on sd1.

Genome-wide introgression lines and their use in genetic and molecular dissection of complex phenotypes in rice (Oryza sativa L.).

Tremendous efforts have been taken worldwide to develop genome-wide genetic stocks for rice functional genomic (FG) research since the rice genome was completely sequenced. To facilitate FG research of complex polygenic phenotypes in rice, we report the development of over 20,000 introgression lines (ILs) in three elite rice genetic backgrounds for a wide range of complex traits, including resistances/tolerances to many biotic and abiotic stresses, morpho-agronomic traits, physiological traits, etc., by selective introgression. ILs within each genetic background are phenotypically similar to their recurrent parent but each carries one or a few traits introgressed from a known donor. Together, these ILs contain a significant portion of loci affecting the selected complex phenotypes at which allelic diversity exists in the primary gene pool of rice. A forward genetics strategy was proposed and demonstrated with examples on how to use these ILs for large-scale FG research. Complementary to the genome-wide insertional mutants, these ILs opens a new way for highly efficient discovery, candidate gene identification and cloning of important QTLs for specific phenotypes based on convergent evidence from QTL position, expression profiling, functional and molecular diversity analyses of candidate genes, highlights the importance of genetic networks underlying complex phenotypes in rice that may ultimately lead to more complete understanding of the genetic and molecular bases of quantitative trait variation in rice.