Optimization of a new method for extraction of cyanidin chloride and pelargonidin chloride anthocyanins with magnetic solid phase extraction and determination in fruit samples by HPLC with central composite design

Cloning of PmMYB6 in Pinus massoniana and an Analysis of Its Function

Phenylpropanoids are crucial for the growth and development of plants and their interaction with the environment. As key transcriptional regulators of plant growth and development, MYB-like transcription factors play a vital role in the biosynthesis of phenylpropanoid metabolites. In this study, we functionally characterized PmMYB6, a Pinus massoniana gene that encodes an R2R3-MYB transcription factor. It was confirmed by qPCR that PmMYB6 was highly expressed in the flowers, xylem, and phloem of P. massoniana. By overexpressing PmMYB6 in tobacco and poplar, we found that transgenic plants had enlarged xylem, increased content of lignin and flavonoids, and up-regulated expression of several enzyme genes of the phenylpropane metabolism pathway to different degrees. The above research results indicate that PmMYB6 is involved in the metabolic flux distribution of different branches of the phenylpropane metabolic pathway, and the results may provide clues for the regulation of metabolic fluxes between flavonoids and the lignin biosynthesis pathways of P. massoniana, as well as provide a basis for the molecular breeding of P. massoniana.

Analysis of Floral Color Differences between Different Ecological Conditions of Clematis tangutica (Maxim.) Korsh

The Clematis tangutica (Maxim.) Korsh. is a wild flowering plant that is most widely distributed on the Qinghai-Tibet Plateau, with beautiful, brightly colored flowers and good ornamental properties and adaptability. In diverse natural environments, the blossom color of C. tangutica (Maxim.) Korsh. varies greatly, although it is unclear what causes this diversity. It was examined using UPLC-MS/MS and transcriptome sequencing for the investigation of various compounds, differentially expressed genes (DEGs), and flavonoid biosynthesis-related pathways in two flowers in two ecological settings. The results showed that a total of 992 metabolites were detected, of which 425 were differential metabolites, mainly flavonoid metabolites associated with its floral color. The most abundant flavonoids, flavonols and anthocyanin metabolites in the G type were cynaroside, isoquercitrin and peonidin-3-O-glucoside, respectively. Flavonoids that differed in multiplicity in G type and N type were rhoifolin, naringin, delphinidin-3-O-rutinoside, chrysoeriol and catechin. Rhoifolin and chrysoeriol, produced in flavone and flavonol biosynthesis, two flavonoid compounds of C. tangutica (Maxim.) Korsh. with the largest difference in floral composition in two ecological environments. In two ecological environments of flower color components, combined transcriptome and metabolome analyses revealed that BZ1-1 and FG3-1 are key genes for delphinidin-3-O-rutinoside in anthocyanin biosynthesis, and HCT-5 and FG3-3 are key genes for rhoifolin and naringin in flavonoid biosynthesis and flavone and flavonol. Key genes for chlorogenic acid in flavonoid biosynthesis include HCT-6, CHS-1 and IF7MAT-1. In summary, differences in flavonoids and their content are the main factors responsible for the differences in the floral color composition of C. tangutica (Maxim.) Korsh. in the two ecological environments, and are associated with differential expression of genes related to flavonoid synthesis.

Anthocyanins in Different Food Matrices: Recent Updates on Extraction, Purification and Analysis Techniques

Anthocyanins (ANCs), a kind of natural pigments, are widely present in food substrates. Evidence has shown that ANCs can promote health in terms of anti-oxidation, anti-tumor, and anti-inflammation. However, the oxidative stability of ANCs limits accurate quantitation and analysis. Therefore, faster, more accurate, and highly sensitive extraction and determination methods are necessary for understanding the role of ANCs in medicine and food. This review presents an updated overview of pretreatment and detection techniques for ANCs in various food substrates since 2015. Liquid-liquid extraction and various green solvent extraction methods, such as accelerated solvents extraction, deep eutectic solvents extraction, ionic liquids extraction, and supercritical fluid extraction, are commonly used pretreatment methods for extraction and purification of ANCs. Liquid chromatography coupled with different detectors (tandem mass spectrometry and UV detectors) and spectrophotometry methods are some of the determination methods for ANC. This study has updated, compared, and discussed different pretreatment and analysis methods. Moreover, the advanced methods and development prospects in this field are comprehensively summarized, which can provide references for further utilization of ANCs.

Ultrasound assisted extraction of bioactive compounds from BRS Violet grape pomace followed by alginate-Ca2+ encapsulation

Objective of this study was to recover bioactive compounds from grape pomace, and to investigate the effect of thermosonication in the rate of aqueous extraction. The best extraction for phenolics and total anthocyanins, was at 55 °C, amplitude of 40% and 6 min of treatment. The ultrasound assisted extraction showed superior results when compared to conventional extraction, extraction averages were: 11% total phenolic compounds, 25% total anthocyanins. The extract obtained by ultrasound showed higher antioxidant capacity when compared to the one obtained by conventional extraction. The alginate-Ca²⁺ capsules were stable when stored in the presence or absence of light, with a reduced t1/2 (absence of light), indicating longer half-life in the absence of light. The use of thermosonication favored greater amounts of bioactive compounds in the grape pomace aqueous extract, and this encapsulated extract in alginate-Ca²⁺ shows good stability and less degradation in the light absence.

VERIFICATION AND OPTIMISATION OF PRESELECTED EXPOSURE PARAMETERS IN SCREENING MAMMOGRAPHY: A CENTRAL COMPOSITE DESIGN METHODOLOGY

In screening mammography, the automatic exposure control (AEC) device selects the optimum exposure parameters for each patient exposure. In practice, this device is calibrated to deliver an optimum figure of merit (FOM) for each set of exposure parameters. This study utilises the central composite design methodology to verify the operating level of the AEC performance for polymethyl methacrylate (PMMA) thicknesses of 4 and 5 cm. Quadratic surface plots reveal that the exposure parameters of the default AEC mode are optimised for the 4-cm thickness of the PMMA. However, the exposure parameters of the 5-cm thickness of PMMA need fine-tuning to obtain a maximum value for the FOM.