Evaluation of the phytochemicals and antioxidant activity of Lophatherum gracile Brongn based on chemical fingerprinting by HPLC with electrochemical detection

Diversity in Pyracantha fortuneana fruits maturity stages enables discrepancy in the phenolic compounds, antioxidant activity, and tyrosinase inhibitory activity

Pyracantha fortuneana (P. fortuneana) fruit is a wild fruit that is popular because of its delicious taste and numerous nutrients, and phenolic compounds are considered to be the main bioactive components in P. fortuneana fruits. However, the relationship between phenolic compounds and their antioxidant and tyrosinase (TYR) inhibitory activities during the ripening process is still unclear. The study compared the influence of the five developmental stages on the accumulation of phenolic compounds, antioxidant activity, and TYR inhibitory activity in the fruits of P. fortuneana. The compounds were identified by offline two-dimensional liquid chromatography-electrochemical detection (2D-LC-ECD) combined with liquid chromatography-tandem mass spectrometry, and the main active ingredients were quantified. The results showed that stage II had higher total phenolic and flavonoid content, as well as higher antioxidant and TYR inhibitory activity, but the total anthocyanin content was lowest at this stage. A total of 30 compounds were identified by 2D-LC-ECD. Orthogonal partial least squares discriminant analysis screened out six major potential markers, including phenolic acids, procyanidins, and flavonoids. In addition, it was found that caffeoylquinic acids, procyanidins, and flavonoids were higher in stage II than in stages I, III, IV, and V, whereas anthocyanins accumulated gradually from stages III to V. Therefore, this study suggests that the changes in antioxidant and TYR inhibitory activities of P. fortuneana during the five developmental stages may be due to the transformation of procyanidins, caffeoylquinic acids, and phenolic glycosides into other forms during the fruit maturation process. Practical Application: Differences in chemical constituents, antioxidant, and tyrosinase inhibitory activities in fruit maturity stages of P. fortuneana were elucidated to provide reference for rational harvesting and utilization of the fruits and their bioactive components. These findings are expected to provide a comprehensive assessment of the bioactive profile and guide the food industrial production.

Separation, identification, and fingerprinting of antioxidant components in persimmon (Diospyros kaki) leaves by offline two-dimensional liquid chromatography with electrochemical detection and tandem mass spectrometry

In this work, the antioxidant components in persimmon (Diospyros kaki) leaves were separated by offline two-dimensional liquid chromatography-electrochemical detection (LC×LC-ECD) and identified by LC-tandem mass spectrometry (LC-MS/MS). A total of 33 antioxidants, mainly proanthocyanidins, and glycosides of kaempferol and quercetin, were identified. The antioxidant assays demonstrated that the fractions collected from the first-dimension LC (1D-LC) possessed considerable radical scavenging capabilities, with correlation coefficients of peak area versus radical scavenging capability of 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) being 0.9335 and 0.9116, respectively. The fingerprinting showed that 37 peaks were present in all samples. The major antioxidant components of persimmon leaves were the glycosides of kaempferol and quercetin. Finally, fourteen antioxidants were quantitatively assessed. Offline LC×LC provided high peak capacity and separation; ECD enabled specific screening and detection of antioxidant components; and MS/MS provided excellent identification capability. In this study, the combination of the three approaches was utilized to screen for antioxidant components in persimmon leaves, with satisfactory findings. In conclusion, this technique is an effective means for rapid analysis of antioxidant components and quality control of medicinal plants, achieving rapid separation of congeners and facilitating more accurate qualitative and quantitative analyses.

Analysis of atorvastatin in environmental waters: Validation of an electrochemical molecularly imprinted polymer sensor with application of life cycle assessment

The widespread presence of pharmaceuticals in wastewater effluents after treatment stands as a significant challenge faced in the field of wastewater management and public health. Governments and the scientific community have worked to meet this urgent need for effective solutions. Nevertheless, the development of detection strategies for pharmaceutical monitorization capable of delivering rapid, on-site, and sensitive responses remains an ongoing necessity. In this work, the performance of a previously developed molecularly imprinted polymer (MIP) based electrochemical sensor for detecting atorvastatin (ATV) in wastewater effluents and surface waters is presented. A simple preconcentration method followed by electrochemical measurements by differential pulse voltammetry (DPV) in 0.1 M phosphate buffer (pH = 7), was implemented. The analytical results were validated with those obtained on a set of 16 water samples by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, a life cycle assessment (LCA) was conducted to compare the environmental impact of both methodologies. The results obtained demonstrated that ATV detection using MIP-sensor was reliable when compared to the results found by UHPLC-MS/MS presenting a robust linear correlation coefficient of 0.843. The LCA results show that the novel MIP-sensor technique has lower associated environmental impacts than UHPLC-MS/MS, when the current analytical protocol for pharmaceuticals detection is applied. These findings highlight the potential of the developed MIP-sensor as an eco-friendly analytical tool for routine analysis and point-of-care monitoring of ATV in WWTP wastewater and surface water samples.

In vitro digestibility and hepato-protective potential of Lophatherum gracile Brongn. leave extract

Lophatherum gracile Brongn. (L. gracile) is a traditional herb for both medicine and food use, but its digestibility and hepato-protective activity is unknown. Herein we investigated the digestibility and hepato-protective potential of L. gracile leave extract (LGE) using in vitro digestion and alcohol-induced oxidative damage models. Compared to the undigested group, the content of phenolics/flavonoids and the antioxidant activity in LGE generally decreased by 9.30-19.97% in the oral and small intestine phase after digestion, while that increased by 9.96-10.17% in the gastric phase. The main phenolics/flavonoids showed promising stability during digestion and their bio-accessiblity ranged from 67.64% to 84.47%. By reducing cellular reactive oxidative species and malonaldehyde levels, LGE (0.23-0.45 mg/mL) pretreatment significantly ameliorated alcohol-induced oxidative damage in HepG2 cells (P < 0.05), and their survival rate increased from 59.23% to 67.76%. These findings suggested that L. gracile could be used for the development of hepato-protective foods.

Metabolomic and transcriptomic analysis of cold plasma promoting biosynthesis of active substances in broccoli sprouts

INTRODUCTION

Broccoli sprouts have great health and commercial value because they are rich in sulforaphane, a special bioactive compound that helps to prevent chronic diseases, such as cancer and cardiovascular disease.

OBJECTIVE

The aim of this study was to increase the levels of active substances in broccoli sprouts and understand their metabolic mechanisms.

METHODOLOGY

Metabolomics based on liquid chromatography-tandem mass spectrometry and transcriptome analysis were combined to analyse the enrichment of metabolites in broccoli sprouts treated with cold plasma.

RESULTS

After 2 min of cold plasma treatment, the contents of sulforaphane, glucosinolates, total phenols, and flavonoids, as well as myrosinase activity, were greatly improved. Transcriptomics revealed 7460 differentially expressed genes in the untreated and treated sprouts. Metabolomics detected 6739 differential metabolites, including most amino acids, their derivatives, and organic acids. Enrichment analyses of metabolomics and transcriptomics identified the 20 most significantly differentially expressed metabolic pathways.

CONCLUSIONS

Overall, cold plasma treatment can induce changes in the expression and regulation of certain metabolites and genes encoding active substances in broccoli sprouts.

Anti-inflammatory and antiviral activities of flavone C-glycosides of Lophatherum gracile for COVID-19

Lophatherum gracile (L. gracile) has long been used as a functional food and herbal medicine. Previous studies have demonstrated that extracts of L. gracile attenuate inflammatory response and inhibit SARS-CoV-2 replication; however, the underlying active constituents have yet to be identified. This study investigated the bioactive components of L. gracile. Flavone C-glycosides of L. gracile were found to dominate both anti-inflammatory and antiviral effects. A simple chromatography-based method was developed to obtain flavone C-glycoside-enriched extract (FlavoLG) from L. gracile. FlavoLG and its major flavone C-glycoside isoorientin were shown to restrict respiratory bursts and the formation of neutrophil extracellular traps in activated human neutrophils. FlavoLG and isoorientin were also shown to inhibit SARS-CoV-2 pseudovirus infection by interfering with the binding of the SARS-CoV-2 spike on ACE2. These results provide scientific evidence indicating the efficacy of L. gracile as a potential supplement for treating neutrophil-associated COVID-19.

Electrochemical-based quantitative fingerprint evaluation strategy combined with multi-markers assay by monolinear method for quality control of herbal medicine

BACKGROUND

Improving the quality control (QC) criterion of herbal medicine (HM) is an ongoing challenge. A rapid and convenient electrochemical analysis technique is now emerging as a promising application for HM QC. So far, extraction and analysis of the overall electroactive components is a key issue need to be solved to improve its application in integral HM QC.

PURPOSE

In this work, using compound liquorice tablets (CLQTs) as an example, we like to put forward a more reliable and accurate quantification method of multi-components for the precise QC of HM. Furthermore, we propose an electrochemical fingerprint-based data mining, extract and synthesis strategy for in-depth and comprehensive QC of HM, qualitatively and quantitatively.

METHODS AND DESIGN

Firstly, the electrochemical quantitative fingerprint of 54 batches of CLQTs from nine manufacturers were developed using B-Z oscillatory system. Secondly, eight characteristic parameters were recorded and compared among samples using intuitive information and PCA. Then, t_und was used to establish the correlation with sample dosage for determination of the relative content of overall electroactive components (Rc). The quantitative determination of five quality markers (Q-markers) were also performed using the novel method, called multi-markers assay by monolinear method (MAML). Finally, after using area integral calculus for electrochemical fingerprint, average linear quantitative fingerprint method (ALQFM) was successfully proposed to extract all latent characteristics for integral quality evaluation of samples.

RESULTS

The t_und and dosage showed a good correlation, by which the obtained Rc displayed different fluctuation among nine manufacturers. Moreover, the contents of five Q-markers obtained by MAML displayed no significant difference with the traditional quantification method. Samples evaluated by ALQFM manifested the integral information and were divided into eight quality grades. The deduced results of correlation between P_l with P_5C, Rc and P_A were more persuasive for demonstrating the reliability and integrity of ALQFM in quality evaluation of HM electrochemical fingerprint.

CONCLUSION

The study confirmed the idea that quantification of Q-markers combined electrochemical-based quality evaluation strategy could be used as a reliable method for HM QC qualitatively and quantitatively from point (precise) to face (integral).

Evaluation of Antioxidants Using Electrochemical Sensors: A Bibliometric Analysis

The imbalance of oxidation and antioxidant systems in the biological system can lead to oxidative stress, which is closely related to the pathogenesis of many diseases. Substances with antioxidant capacity can effectively resist the harmful damage of oxidative stress. How to measure the antioxidant capacity of antioxidants has essential application value in medicine and food. Techniques such as DPPH radical scavenging have been developed to measure antioxidant capacity. However, these traditional analytical techniques take time and require large instruments. It is a more convenient method to evaluate the antioxidant capacity of antioxidants based on their electrochemical oxidation and reduction behaviors. This review summarizes the evaluation of antioxidants using electrochemical sensors by bibliometrics. The development of this topic was described, and the research priorities at different stages were discussed. The topic was investigated in 1999 and became popular after 2010 and has remained popular ever since. A total of 758 papers were published during this period. In the early stages, electrochemical techniques were used only as quantitative techniques and other analytical techniques. Subsequently, cyclic voltammetry was used to directly study the electrochemical behavior of different antioxidants and evaluate antioxidant capacity. With methodological innovations and assistance from materials science, advanced electrochemical sensors have been fabricated to serve this purpose. In this review, we also cluster the keywords to analyze different investigation directions under the topic. Through co-citation of papers, important papers were analyzed as were how they have influenced the topic. In addition, the author’s country distribution and category distribution were also interpreted in detail. In the end, we also proposed perspectives for the future development of this topic.