Bioanalytical method validation for the quantification of the chlorogenic acid in Capsicum baccatum through High Performance Liquid Chromatography (HPLC-DAD)

Validation and screening of patulin in apple beverages marketed in Morocco

Patulin is one of the mycotoxins frequently detected in apples and derivatives, representing a major food safety risk. This study aimed to validate a high-performance liquid chromatography (HPLC) method with an ultraviolet (UV) detector for patulin quantification and assess its occurrence in apple beverages marketed in Morocco. The validation parameters showed satisfactory results with adequate linearity (R > 0.997), a relative standard deviation below 2.5%, repeatability between 3.6 and 7.1%, reproducibility between 3.9 and 11.5%, a limit of quantification (LOQ) of 4 μg/L, and recoveries close to 100% for three levels. Analysis of 30 samples revealed patulin levels ranging from 0 to 16.36 μg/L, with 50% of samples showing negative levels. All positive results remained below the regulatory maximum limit of 50 μg/L. These findings affirm the efficacy of the HPLC proposed method in ensuring compliance with patulin regulations in apple beverages, underlining its importance in safeguarding food safety.

Screening, isolation, and activity evaluation of potential xanthine oxidase inhibitors in Poria Cum Radix Pini and mechanism of action in the treatment of gout disease

Poria Cum Radix Pini is a rare medicinal fungus that contains several potential therapeutic ingredients. On this basis, a particle swarm mathematical model was used to optimize the extraction process of total triterpenes from P. Cum Radix Pini, and xanthine oxidase inhibitors were screened using affinity ultrafiltration mass spectrometry. Meanwhile, the accuracy of the ultrafiltration assay was verified by molecular docking experiments and molecular dynamics analysis, and the mechanism of action of the active compounds for the treatment of gout was analyzed by enzymatic reaction kinetics and network pharmacology. A high-speed countercurrent chromatography method combined with the consecutive injection and the economical two-phase solvent system preparation using functional activity coefficient of universal quasichemical model (UNIFAC) mathematical model was developed for increasing the yield of target compound. In addition, dehydropachymic acid and pachymic acid were used as competitive inhibitors, and 3-O-acetyl-16alpha-hydroxydehydrotrametenolic acid and dehydrotrametenolic acid were used as mixed inhibitors. Then, activity-oriented separation and purification were performed by high-speed countercurrent chromatography combined with semi-preparative high-performance liquid chromatography and the purity of the four compounds isolated was higher than 90%. It will help to provide more opportunities to discover and develop new potential therapeutic remedies from health care food resources.

A Rapid and Sensitive UHPLC-MS/MS Method for Determination of Chlorogenic Acid and Its Application to Distribution and Neuroprotection in Rat Brain

Chlorogenic acid (5-CQA) is a phenolic natural product that has been reported to improve neurobehavioral disorders and brain injury. However, its pharmacokinetics and distribution in the rat brain remain unclear. In this study, we established a rapid and sensitive UHPLC-MS/MS method for the determination of 5-CQA in rat plasma, cerebrospinal fluid (CSF), and brain tissue to investigate whether it could pass through the blood-brain barrier (BBB) and its distribution in the rat brain, and a Caenorhabditis elegans (C. elegans) strain paralysis assay was used to investigate the neuroprotective effect of 5-CQA in different brain tissues. Chromatographic separation of 5-CQA and glycyrrhetinic acid (GA, used as internal standard) was completed in 0.5 min, and the full run time was maintained at 4.0 min. Methodological validation results presented a high accuracy (95.69-106.81%) and precision (RSD ≤ 8%), with a lower limit of quantification of 1.0 ng/mL. Pharmacokinetic results revealed that 5-CQA can pass through the BBB into the CSF, but the permeability of BBB to 5-CQA (ratio of mean AUC0-∞ of CSF to plasma) was only approximately 0.29%. In addition, 5-CQA can penetrate into the rat brain extensively and is distributed with different intensities in different nuclei. A C. elegans strain paralysis assay indicated that the neuroprotective effect of 5-CQA is positively correlated with its content in different brain tissues. In conclusion, our study for the first time explored the BBB pass rate and brain tissue distribution of 5-CQA administered via the tail vein by the UHPLC-MS/MS method and investigated the potential main target area of 5-CQA for neuroprotection, which could provide a certain basis for the treatment of nervous system-related diseases of 5-CQA.

Evaluation of Lonicera etrusca var. etrusca Santi (Caprifoliaceae) Stem and Leaf in Terms of Anatomical Structures and Some Phenolic Compounds

Objectives

The genus Lonicera includes medicinally important plants. Two varieties of L. etrusca have been recorded in Türkiye. Anatomical structures and phytochemical contents are important in the diagnosis and identification of medicinal plants. This study included stem and leaf anatomy of L. etrusca var. etrusca and high performance liquid chromatography (HPLC) analysis of the methanol extracts obtained from these parts.

Materials and Methods

Plant materials were collected from Ankara. Methanol extracts were prepared from the stems and leaves by ultrasonic bath. The amounts of chlorogenic acid and caffeic acid that are major compounds in the stem and leaves, were determined by HPLC. For anatomical studies, specimens were preserved in 70% alcohol. Transverse and surface sections were prepared by hand. Detection of tissues was performed using Sartur reagent. Anatomical specimens were examined using a light microscope and microphotographed.

Results

In HPLC analysis, the highest amount of chlorogenic acid was determined in the leaf (1.148%), and the highest amount of caffeic acid (0.156%) was determined in the stem. In the anatomical analysis, it was observed that the stem was disc-shaped and hollow; pericycle is in a ring form, consists of fibre-like cells with thick walls and wide lumina; cork occurs adjoining pericyclic fibers; thin-walled pith cells containing dense druse crystals. The leaf lamina is bifacial in the transverse section; palisade and spongy parenchyma, both contain abundant starch grains; solitary druse crystals are sparse in the leaf mesophyll; the stomata were observed only on the lower surface with 3-5 subsidiary cells. With this study, L. etrusca var. etrusca has been clarified in terms of its anatomical structures and phenolic compounds.

Conclusion

The chemical contents and anatomical structures of the plant may contain important information that can be used in classification. This study may support in taxonomically classification for the L. etrusca var. etrusca.

Stability of Chlorogenic Acid from Artemisiae Scopariae Herba Enhanced by Natural Deep Eutectic Solvents as Green and Biodegradable Extraction Media

A green and inexpensive natural deep eutectic solvent (NADES) was screened and integrated with an ultrasonic technique for extracting chlorogenic acid (CGA) from artemisiae scopariae herba. Response surface methodology was employed to investigate significant factors and optimize their influence. Proline-malic acid exhibited an excellent extraction capacity with a yield of 28.23 mg/g under the optimal conditions of water content of 15% (wt), solid-liquid ratio of 1.0/10 (g/mL), ultrasonic power of 300 W, and extraction time of 25 min. Simultaneously, the stability and antioxidant activity analysis exhibited a better performance of CGA in NADES than that in water and ethanol. The hydrogen-bonding interaction between CGA and natural deep eutectic molecules enhanced the stability and meanwhile protected the antioxidant activity of CGA.

Wearable Analytical Platform with Enzyme-Modulated Dynamic Range for the Simultaneous Colorimetric Detection of Sweat Volume and Sweat Biomarkers

In this manuscript, we introduce a wearable analytical platform that simultaneously measures the concentration of sweat lactate and sample volume. It contains two sensors entirely made of filter paper that can be easily affixed on the skin with medical-grade tape. The lactate biosensor features a unique signal modulation mechanism that enables fine-tuning the dynamic range. It consists of adding a competitive enzyme inhibitor in different reservoirs. Thanks to this, it is possible to choose between a very low limit of detection (0.06 mM) and a linear response in the physiological concentration range (10-30 mM). The sweat volume sensor was obtained by adding a reservoir containing gold nanoparticles. As the wearer sweats, the nanoparticles are carried through a paper channel. This is used to gauge the volume of sample by measuring the distance traveled by the nanoprobes. Using fine-tuned lactate biosensors and combining them with the volume sensors allowed us to quantify variations in the levels of sweat lactate independently of the wearer's sweat rate during an exercise routine. The platform design can be customized to meet the end user's needs, which makes it ideal for developing a wide array of disposable wearable biosensors.

Arabica and Conilon coffee flowers: Bioactive compounds and antioxidant capacity under different processes

This study presents innovative research for comparison of the effect of the different dehydration techniques and methods of extraction on the antioxidant potential and bioactive compounds of Conilon and Arabica coffee flowers. The compounds were analyzed by high performance liquid chromatography and the antioxidant capacity evaluated by the 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide assays. Among the compounds evaluated, trigonelline, gallic acid, chlorogenic acid, and caffeine were identified, with trigonelline and caffeine being those with the highest concentration. The investigated factors significantly influenced the profile of the bioactive compounds identified, and the antioxidant capacity. The 92 °C infusion of freeze-dried Conilon coffee flowers, in general, showed greater antioxidant capacity by ABTS and DPPH assays, as well as total phenolic content. Lyophilization had a positive influence on maintaining the content of phenolic compounds and antioxidant capacity of the samples. Coffee flowers proved to be a potential raw material for making tea-like drinks.