High-performance Liquid Chromatography Analysis Research Articles

Optimising microalgal dyes extraction design for stable dye-sensitized solar cells: Chromatographic insights on bio-deterioration and longevity.

The demand for sustainable energy solutions has increased interest in natural microalgal dyes as photosensitizers in dye-sensitized solar cells (DSSCs). This study addresses the critical issue of maximizing dye integrity and yield during extraction, particularly the degradation that occurs at temperatures above 60°C. Our investigation of dye extraction from Asterarcys quadricellulare and Scenedesmus sp. using hot solvent methods revealed significant findings. High-Performance Liquid Chromatography (HPLC) analysis identified essential pigments, including Chlorophyllide a and β-carotene. Our research found that temperatures above 60°C reduce chlorophyll (Chl) stability and extraction efficiency. Using multiple wavelengths in a photodiode array (PDA) detector improves Chl identification by targeting distinct absorption peaks, resolving overlap with other compounds, and confirming purity. This approach also helps validate extraction methods and ensures accurate quantification. Since high temperatures are detrimental to Chl stability, this method is crucial for reliable analysis and longer dye storage. Ethanol outperformed methanol in extraction efficiency, while the stability of the dyes was tied to specific derivatives. Notably, Scenedesmus sp. showed better preservation of chlorophyll compounds, influenced by extraction temperature and solvent characteristics. This research underscores the potential for optimising natural dye extraction methods, offering a pathway to enhance the sustainability and cost-effectiveness of DSSC production, thus contributing to greener energy technologies.

A Low-cost and Rapid Method for Determination of Five Flavonoids in Herbal Medicines with Rutin by HPLC-UV at Equal Absorption Wavelength

Background: Flavonoid is a type of active constituent in herbs and always used as the quality control markers of herbal medicines. Owing to the extensive diversity of flavonoids, numerous reference compounds are necessitated for the analysis of flavonoids, and some are usually very expensive, which engenders challenges in the analysis of flavonoids in herbal medicines. Consequently, the development of a simple, rapid, and reference compounds saving method is important for the determination of flavonoids in herbal medicines. Objective: In order to develop a high-performance liquid chromatography (HPLC) method for the determination of 5 flavonoids (mangiferin, hesperidin, baicalin, buddleoside, and rutin) in five herbal medicines (Anemarrhenae rhizome, Sophorae flos, Citri reticulatae pericarpium, Scutellariae radix, and Chrysanthemi indici flos) with rutin. Methods: Five herbal medicine samples were prepared according to the Chinese Pharmacopoeia which includes ultrasound and reflux methods. The separation of the sample was performed on a PoroShell 120 EC-C18 (4.6 mm×100 mm, 2.7 μm) by gradient elution with 0.1% formic acid and acetonitrile at a flow rate of 1.0 mL/min. The wavelengths were set as follows: Anemarrhenae rhizome (363 nm), Sophorae flos (256 nm), Citri reticulatae pericarpium (236 nm), Scutellariae radix (263 nm), Chrysanthemi indici flos (354 nm). Results: The method validation showed that the established HPLC method was accurate and stable for quantitative analysis of flavonoids in five herbal medicines. The comparative analysis revealed that the determination results of the current HPLC method and Chinese Pharmacopoeia method are consistent, exhibiting less than 1% relative error. Remarkably, the developed HPLC method needs one cheapest reference compound (rutin) and costs 8 min for sample HPLC analysis. Conclusion: The developed HPLC method for quantitative analysis of five flavonoids in five herbal medicines is simple, rapid, and reference compound saving, which provides a good alternative method for quality control of flavonoids in herbal medicines.

Simultaneous site-directed mutagenesis for soybean ß-amyrin synthase genes via DNA-free CRISPR/Cas9 system using a single gRNA.

We generated soybean mutants related to two ß-amyrin synthase genes using DNA-free site-directed mutagenesis system. Our results suggested that one of the genes is predominant in the soyasaponin biosynthesis. Soyasaponins, which are triterpenoid saponins contained in soybean [Glycine max (L.) Merril], are responsible for the astringent aftertaste of soyfood, and their complete elimination from soybean seeds is a key challenge in the development of cultivars with improved taste. While the loss of function in the ß-amyrin synthase genes (GmBAS1 and GmBAS2) has proven effective in reducing soyasaponin content in soybean seeds, the specific functional roles of these genes remain unclear. In this study, site-directed mutagenesis was performed on two GmBAS loci using a DNA-free clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated endonuclease 9 (Cas9) system. A complex of sgRNA targeting sequences conserved in the two loci and Cas9 protein was introduced into the shoot apical meristems of soybean embryonic axes via bombardment. Cleaved amplified polymorphic sequences (CAPS) analysis conducted 1month post-bombardment revealed that 138 seedlings out of 1,467 screened exhibited mutations at one or both GmBAS loci. CAPS and sequencing analysis in the subsequent generation identified a total of 16 plants with inheritable mutations ranging from one to ten nucleotides. High-performance liquid chromatography (HPLC) analysis showed that site-directed mutagenesis in the GmBAS1 locus resulted in the absence of soyasaponins in mature seeds, as well as in young roots, stems, and leaves. These findings demonstrate that GmBAS1 is the predominant ß-amyrin synthase gene in soybean plants. In addition, the DNA-free CRISPR/Cas9 system was shown to be highly efficient in inducing simultaneous mutagenesis at two target loci using a single gRNA.

Banana rachis nanocellulose: a natural stabilizer for Pickering nanoemulsion and its potential as a carrier of β-carotene in food systems.

Incorporating β-carotene into food systems improves nutritional value by providing a natural source of vitamin A. However, maintaining its stability during processing and storage is a significant barrier for its bioavailability. This study investigated the utilization of banana rachis nanocellulose (BRNC) as a natural stabilizer in the formulation of Pickering nanoemulsion (PNE). Parameters were optimized for developing PNE using BNRC. A 20 g kg -1 concentration of BNRC was found to be suitable in terms of particle size and zeta potential. The PNE, with a particle size of 196 nm and a polydispersity index (PDI) of 0.463, remained stable for 35 days. β-Carotene (1 g kg-1) on encapsulation in PNE showed enhanced chemical stability with a retention rate of 0.81. The BRNC-based PNE demonstrated enhanced stability against phase separation. Additionally, β-carotene-infused PNE mayonnaise was developed and characterized. Hydroperoxide formation in developed mayonnaise increased in control sample up to day 14, while samples with β-carotene showed no significant increase (P > 0.05) throughout the analysis period. Furthermore, mayonnaise added with the BRNC-based PNE enriched with β-carotene exhibited improved functionality, including enhanced rheological (R2 = 0.99), textural, and colour attributes. High-performance liquid chromatography (HPLC) analysis showed 612.6 ± 0.8 μg β-carotene kg -1 of mayonnaise. The developed mayonnaise successfully reduces fat content while enhancing its overall functionality. The potential of BRNC as a promising bio-based stabilizer was thus elucidated for the development of functional food products with improved nutritional value and stability. © 2025 Society of Chemical Industry.

Investigation on Bowel Regulation and Constipation Relief Based on the Microbial Fermentation Solution of Cassia Seed.

As digestive health issues rise and interest in natural therapies grows, traditional herbs like Cassia Seed are gaining attention for their antioxidant, laxative, and digestive benefits. This study aimed to optimize the fermentation conditions of Cassia seed using microbial technology to enhance the content of anthraquinone compounds, thereby augmenting its pharmacological effects, particularly in promoting intestinal peristalsis and alleviating constipation. Fermentation of Cassia Seed was conducted under controlled microbial conditions. High-performance liquid chromatography (HPLC) was employed to analyze the anthraquinone profile of the fermented solution. Mouse model was utilized to evaluate biochemical markers and intestinal functions, while in the zebrafish constipation model, calcein was utilized as a marker to monitor intestinal function and excretion dynamics. Cassia Seed was fermented under controlled microbial conditions. HPLC was employed to analyze the anthraquinone profile of the fermented solution. Mouse models were utilized to evaluate biochemical markers and intestinal functions, while a zebrafish constipation model used calcein as a marker to monitor intestinal function and excretion dynamics. The optimized fermentation significantly increased the content of anthraquinone compounds, including substances like emodin, aloe-emodin, rhein, chrysophanol, and physcion, as confirmed by HPLC analysis. In a mouse constipation model, the fermented solution reduced nitric oxide (NO) levels while increasing acetylcholine (Ach) and gastrin (Gas) levels, thereby promoting intestinal peristalsis and accelerating bowel movements. Additionally, the fermented solution facilitated repair of the colonic mucosa in mice without significant pathological damage such as degeneration or fibrous tissue proliferation. In the zebrafish model, the fermented Cassia Seed solution reduced calcein fluorescence intensity, indicating enhanced intestinal peristalsis and accelerated bowel movements, thereby decreasing calcein retention time in the body. This study investigated the potential clinical applications of fermented Cassia seed ferment in digestive health, providing a theoretical basis and inspiration for further research and development. Additionally, it offers new insights and possibilities for the development of novel natural medicines or functional foods aimed at improving constipation and promoting intestinal health.

Occurrence of Alternaria Toxins, Ochratoxin A and Aflatoxins B1 in Green Arabic Coffee (Coffea arabica) in Saudi Arabia: Risk Assessment on HepG-2 Cell Line and Male Albino Rats

Arabica coffee (Coffee arabica L.) is among the most popular and widely consumed drinks globally today. The current study aimed to detect and quantify of potential mycotoxins in coffee beans and to investigate their potential risk on HepG-2 human liver cancer cells and male albino rats. Eighteen fully matured coffee beans samples were collected from different geographical locations in Saudi Arabia. Mycotoxins detected and quantified utilizing high-performance liquid chromatography (HPLC). Cytotoxicity of the detected toxins was investigated utilizing the MTT assay method toward HepG-2 cells and male albino rats. Cytotoxic properties of the detected mycotoxins were investigated at doses of 31.25, 62.50, 125, 250 and 500 µg/ml following exposure durations of 24 and 48 h in comparison with control. HPLC analysis revealed the detection of four Alternaria toxins (ALT-Ts) namely Altenuene (ALT), Tenuazonic acid (TA), Alternariol (AOH), and Altenuisol being AOH reported as the frequently detected mycotoxin in 18 coffee beans samples representing 75 % with quantity ranged 0.98 to 8.97 μg/g. OTA was frequently detected (10 samples, 55.5%) in concentrations varied from 0.75 to 9.87 μg/g. In addition, Aflatoxin B1 was also detected with low quantity ranged 0.89 to 3.22 μg/g. Treatment of HepG-2 cell line with combined Alternaria toxins (ALT, TeA, AOH, and Altenuisol), Aflatoxin B1 (AFB1) and Ochratoxin A (OTA) as well as their combination triggered a decline in cell viability that was proportional to the dose administered. The elevated doses (62.50, 125, 250 and 500 µg/ml) notably reduced cell viability and induced cellular damages when contrasted with the lowest dose (31.25 µg/ml) and control. The IC50 for the tested mycotoxins registered for ALT-Ts, AFB1 and OTA as well as their combination were 115.95, 56.68, 59.86 and 31.05 µg/ml after 48 h of exposure. Secreting inflammatory markers (Interleukin-6 (IL-6), interleukin-1β (IL-1β) and COX-2), and oxidative markers (total antioxidant capacity (TAC), glutathione (GSH) and nitrite (NO) were downregulated by all mycotoxins with the highest decrease induced by their mixture. Malonaldehydes (MDA) and TAC were significantly increased by all toxins in treated rats. Hematological results revealed that AFB1, OTA and ALT-Ts-treated rats exhibited a notable decline in hemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs), and packed cell volume % (PCV). However, single and double dose-treated rats with OTA, Mix1 and Mix2 exhibited a marked increase in WBCs. The results demonstrated a notable decline in liver and kidney functions in all mycotoxins-treated rats. The studied organs (liver, kidney and spleen) exhibited significant damage, with the most severe alterations observed in the Mix1 and Mix2-treated group in comparison with the groups receiving individual treatment. This indicates that the mixture of AFB1, ALT-Ts and OTA had an enhanced toxic consequence against treated HepG-2 cell line and rats. Our results indicated the synergistic effect of the combined different mycotoxins against HepG-2 human liver cancer cells and male albino rats. This work could help fill in data gaps and enhance risk assessment for human health by addressing some of the possible risks associated with Alternaria toxins

Lactobacillus acidophilus YL01 and its exopolysaccharides ameliorate obesity and insulin resistance in obese mice via modulating intestinal specific bacterial groups and AMPK/ACC signaling pathway.

Probiotics intervention by Lactobacillus acidophilus has potential effect on alleviating obesity and insulin resistance. However, the limited knowledge of functional substances and potential regulatory mechanisms hinder their widespread application. Herein, L. acidophilus YL01 was firstly isolated from Chinese traditional yogurt, demonstrating inhibitory activities on amylase and glucosidase that are comparable to those of L. rhamnosus LGG. Besides, the oral administration of L. acidophilus YL01 and its EPS significantly reduced body weight in high-fat mice (p < 0.05), as well as fat accumulation in liver and adipocytes. Moreover, they not only reduced fasting blood glucose and glucose/insulin resistance, but also improved dyslipidemia, liver function and inflammation. Further high-performance liquid chromatography analysis and Fourier transform infrared spectroscopy indicated that EPS is an acidic polysaccharide, characterized by a molecular weight of 952 kDa and predominantly composed of glucose. Additionally, the mechanism investigation revealed that the L. acidophilus YL01 and EPS demonstrated limited efficacy in restoring the composition of gut microbiota, but rather exerted an influence on the abundance of specific bacterial groups. The enrichment of the bacterial groups resulted in the increase of acetic acid and butyric acid, which further mediates the gut-liver crosstalk in regulating lipid metabolism by the activation of AMPK/ACC pathway.

Heterologous expression of a recombinant ACE inhibitory peptide LYPVK and its potential antihypertensive action mechanism.

Enzymatic hydrolysis approach is commonly employed for preparation of active peptides, while the limited purity and yield of produced peptides hinder further development of action mechanisms. This study presents the biotechnological approach for the efficient production of recombinant angiotensin converting enzyme (ACE) inhibitory peptide LYPVK and investigates its potential antihypertensive action mechanism. DNA encoding sequence of recombinant peptide was designed to form in tandem, which was expressed in Escherichia coli BL21 (DE3). The expressed tandem repeat protein with molecular weight of 13.4 kDa was verified by high performance liquid chromatography (HPLC) and amino acid composition. Subsequently, LYPVK was generated following His-tag removal and trypsin-mediated cleavage of the purified protein, which was performed HPLC and liquid chromatography-mass spectrometry (LC-MS) analysis. LYPVK exhibited an IC50 value of 10.6 ± 0.86 μg/mL, demonstrating a non-competitive mode of action and resistance to gastrointestinal enzyme hydrolysis and heat conditions. Molecular docking results showed that LYPVK interacted with ACE through conventional hydrogen bonds and hydrophobic interactions. Except for ACE, ALB, SRC, PPARG, and MMP9 are identified as potential key targets for its antihypertensive activity by network pharmacological analysis. This study provides a promising biotechnological approach for the preparation of active peptides with high purity and yield.

In vitro antischistosomal activity of Artemisia species.

Praziquantel is currently the only effective treatment for schistosomiasis, but several limitations underscore the need for new therapeutic agents. Recent promising in vitro results with Artemisia species and the success of A. annua and its active compound artemisinin in treating parasitic infections warrant the need for further studies. Here we evaluate the in vitro activity of nine Artemisia species, including previously untested species, against newly transformed schistosomula (NTS) and adult Schistosoma mansoni. Three extracts were prepared: an aqueous infusion, a dichloromethane (DCM) fraction of the aqueous infusion, and a DCM extract. All samples were tested for activity at concentrations ranging from 1-25 µg/ml against NTS and the most promising against the adult S. mansoni. All aqueous infusions showed inferior activity against NTS as opposed to the DCM fractions of the infusions and DCM extracts of A. abrotanum, A. arborescens, A. afra, and A. scoparia which displayed superior activity as compared to the positive control praziquantel. The DCM fraction infusions of A. afra (BB) were the most active with IC50 values of 0.35 µg/ml against NTS and 4.5 µg/ml against adult worms. Chemical fingerprinting using High-performance liquid chromatography (HPLC) analysis of the samples revealed some phytochemical similarities and significant differences between the species tested. This study provides supporting evidence of the antischistosomal potential of Artemisia spp. and warrants more in-depth research to identify potential novel therapeutic agents for the treatment of schistosomiasis.

Interaction Analysis between Cationic Lipid and Oligonucleotide with a Lipid Membrane-Immobilized Monolith Silica Column: A High-Performance Liquid Chromatography Approach.

Understanding the interactions between lipid membranes and nucleotide drugs is crucial for nucleic acid therapy. Although several methods have been employed to evaluate nucleotide-lipid membrane interactions, these interactions can be complex; this complexity arises from how external factors, such as ionic strength or temperature, influence the lipid membrane's overall properties. In this study, we prepared a lipid membrane-immobilized monolithic silica (LMiMS) column for high-performance liquid chromatography (HPLC) analysis to understand interactions between the lipid membrane and nucleic acid. First, the Raman shift, zeta potential, fluidity, and polarity of the LMiMS-column membrane were analyzed and compared to dispersed liposomes (not immobilized) with the same lipid composition. The results indicated that the column can effectively imitate the temperature-dependent properties of the lipid membrane, suggesting that the immobilized lipid membrane can be used as a model of dispersed liposomal membranes. Subsequently, HPLC was performed to analyze the interaction between the lipid membrane and oligonucleotides. The retention factor k was determined as an interaction factor between the LMiMS column and nucleic acid models (poly 10, 25, and 50mer dC) at various temperatures and mobile phase salt concentrations. The results revealed that changes in membrane interaction were significant by the phase state and salt concentration. Further analysis of the retention factor k showed that the interaction is weak below the phase transition temperature but strong above the phase transition temperature. The results indicate that membrane properties (rigidity and polarity) are also related to membrane interaction, which can be evaluated with the LMiMS column. This analytical method can provide a new perspective on estimating the interactions between target molecules and the lipid membrane through their temperature-induced dynamics. From these results, our method could be useful for analyzing lipid membrane-oligonucleotide interactions.

Analysis of glipizide and pravastatin sodium drug molecules at trace level by using magnetic solid phase extraction and HPLC-DAD system.

An easy applicable and selective sample preparation technique has been developed for trace and simultaneously analysis of Glipizide (GLP) and Pravastatin (PST) molecules in biological matrices based on magnetic solid phase extraction (MSPE) and high-performance liquid chromatography (HPLC). A new magnetic adsorbent including Fe3O4@TEOS-Melamine has been synthetized and characterized for extraction studies. Experimental variables of MSPE were examined and optimized step by step such as pH, adsorption and desorption conditions, time effect, etc. Simultaneous HPLC analysis of GLP and PST molecules was performed by isocratic elution of a mixture of acetonitrile: phosphate buffer (pH:3.0, 0.02M) (35:65) with flow rate 1.0mLmin-1. Analytical signals obtained from DAD detector were recorder in 238 and 226nm for PST and GLP, respectively. The limit of detections (LOD) for proposed method were 3.17ngmL-1 for PST and 3.03ngmL-1 for GLP molecules. Consequently, accuracy and precision of developed method were tested by means of recovery tests in synthetic urine and saliva samples. RSD % values were lower than 6.1% and recovery values were in the range of 98.5-103.3% for both molecules.

Molecular, Metabolic, and Physiological Responses to Progressive Biotic Stress Caused by Cucumber Mosaic Virus and Turnip Mosaic Virus in Saffron

The economic value of the saffron stigma is primarily due to three crucial apocarotenoids: crocin, picrocrocin, and safranal, which contribute to its color, flavor, and aroma. These compounds make saffron highly valuable in various industries. Plant viruses like the cucumber mosaic virus (CMV) and turnip mosaic virus (TuMV) are significant threats to agricultural crops worldwide, causing economic losses. To elucidate the influence of viral stress on the quality of saffron, morphological, physiological, biochemical, and molecular indexes were assessed. Under the stress of both viruses, typical viral symptoms appeared. The lowest contents of leaf pigments, flowering performance, petal anthocyanin, greenness, and photosynthesis properties were observed in plants infected with CMV and TuMV. According to high-performance liquid chromatography (HPLC) analysis, CMV inoculation led to the highest reduction in crocin and safranal content, while inducing the highest increase in picrocrocin compared to the mock treatment. Gene expression analysis involved in the biosynthesis of crucial secondary metabolites showed a high correlation with the content of each metabolite. CMV inoculation resulted in the lowest expression of CsALDH31l and the highest expression of CsUGT709G1 compared with the mock treatment. Our findings demonstrate the association between virus stress and changes in the metabolism of the saffron medicinal plant.

Methanolic Leaves Extract of Ziziphus spina-christi Inhibits Cell Proliferation and Migration of HER2-Positive Breast Cancer via p38 MAPK Signaling Pathway.

Human epidermal growth factor receptor 2 (HER2) is a subtype of breast cancer that is associated with poor prognosis and low survival rates. The discovery of novel anti-cancer agents to manage this subtype of cancer is still needed. Ziziphus spina-christi (ZSC) is a plant species that is native to Qatar. It exerts various biological activities, including cytotoxicity as it contains different essential bioactive constituents, mainly rutin and quercetin. To examine the outcome of ZSC on HER2-positive breast cancer, we standardized the ZSC methanolic leaves extracted by Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) analysis using the flavonoids rutin and quercetin as marker compounds. Here we used two HER2-positive breast cancer cell lines, ZR-75-1 and SK-BR-3, and the chorioallantoic membrane as an angiogenesis model. We found that ZSC extract significantly reduces viability, alters the normal morphological phenotype of HER2-positive breast cancer cells, and inhibits cell migration as well as colony formation; this is accompanied by deregulating different apoptotic markers such as Bax/Bcl-2 and NF-κB in both cell lines. Additionally, ZSC methanolic extract significantly represses the angiogenesis of the chorioallantoic membrane model. Moreover, the molecular pathway investigations pointed out that ZSC extract represses the activity of HER2 and p38 MAPK which could be the main pathways behind the effect of ZSC in HER2-positive cells. Collectively, our results support the potential role of ZSC in the management of HER2-positive breast cancer and form the basis for future investigations.

Improving Antioxidant Effect of Stemona tuberosa by Fermentation with Endophytic Fungus Penicillium expansum STRB13

Background: Stemona tuberosa Lour. is a plant belonging to the genus Stemona (Stemonaceae) that has been utilized in traditional Chinese medicine (TCM) for its antitussive and antiparasitic properties. Endophytic fungi have been shown to play an important role in the growth and metabolism of plants. Fermentation involving endophytic fungi tends to result in the production of new or more potent pharmacological compounds. Objective: The study aims to enhance the antioxidant activity of S. tuberosa by fermenting it with a symbiotic endophytic fungus. Methods: Seven symbiotic endophytic fungi were used to screen and ferment S. tuberosa to improve antioxidant activity estimated by 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric ion-reducing antioxidant power (FRAP). The chemical constituent changes were characterized by ultraviolet (UV) spectrum and high-performance liquid chromatography (HPLC) analysis. Results: Penicillium expansum STRB13, an endophytic fungus associated with S. tuberosa, was screened for its ability to enhance antioxidant capacity through fermentation. The fermentation of S. tuberosa using P. expansum STRB13 significantly improved its DPPH radical scavenging activity, achieving an IC50 value of 24.2 μg/mL. Additionally, the ferric reducing antioxidant power (FRAP) of the fermented sample was fourteen times greater, measuring 388.1 ± 32.6 μmol/L compared to 27.5 ± 1.0 μmol/L in the blank sample. Differences observed between the blank and P. expansum STRB13 fermented S. tuberosa (FST) in UV spectra and HPLC analysis indicated the production of new aromatic phenolic compounds through fermentation, which contributed to the enhanced antioxidant activity. Conclusion: This is the first time reporting on the fermentation processing of S. tuberosa with symbiotic endophytic fungus. This study revealed that P. expansum STRB13 FST will be an alternative natural antioxidant. Fermentation with symbiotic endophytic fungus is a new approach to processing TCM and discovering new compounds.

Occurrence analysis of alpha-mangostin from different organs of Garcinia mangostana L.

Alpha-mangostin (AM) is a naturally occurring xanthone with remarkable pharmacological properties, including anti-inflammatory, anti-bacterial, and antioxidant effects. The compound is commonly extracted from the pericarps of Garcinia mangostana L. fruits, but its seasonal availability is limited. Investigating the potential of using various organs of the tree for AM extraction can help mitigate limitations imposed by the seasonal availability of fruits. This study employs the Soxhlet extraction method and gravitational column chromatography for the preparation of AM from various plant organs. The purity of the compound in the extract was quantitatively determined using high-performance liquid chromatography analysis. The stem barks demonstrated the highest yield at 1.3%, with a concentration of 324.593 µg/mL and a purity of 95.215% for AM. The finding is expected to assist in uncovering alternative sources of AM and contribute to sustainable utilisation of the tree, as various plant organs could be employed in AM extraction.

Sensitive measurement of polycyclic aromatic hydrocarbons based on strong enrichment from magnetic covalent organic framework before high performance liquid chromatography analysis

Sensitive measurement of polycyclic aromatic hydrocarbons based on strong enrichment from magnetic covalent organic framework before high performance liquid chromatography analysis

Polycatechol coated cigarette filter as a sorbent for microextraction by packed sorbent of acidic non-steroidal anti-inflammatory drugs (NSAIDs) from wastewater samples

In this study, we employed microextraction by packed sorbent (MEPS) using polycatechol-coated cigarette filters (PCCFs) as a sorbent to extract acidic non-steroidal anti-inflammatory drugs (NSAIDs) from water samples, followed by high-performance liquid chromatographic analysis. The formation of coating on cigarette filter was confirmed by Fourier transform infrared (FT-IR) spectroscopy, UV–vis diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). The effect of coating parameters on extraction efficiency of acidic NASIDs were investigated and 106.0 mg of Na2CO3, 30.0 mg of catechol and 3 h coating time were selected as optimum conditions. Additionally, other factors affecting the analyte extraction efficiency were optimized including a sample solution pH of 2.0, 700.0 µL of methanol as the elution solvent, 3 sorption cycles, 2 desorption cycles, and a 1.5 ml sample volume. Under the optimum conditions the calibration curves for all three analytes were draw and the analytical performance parameters including linear dynamic range (50.0–1000.0 µg.L−1 for naproxen and diclofenac and 100.0–500.0 µg.L−1 for ibuprofen) with R2 > 0.9982, limit of detection (LOD < 45.3 µg.L−1), precision (RSD% < 6.5), accuracy (recovery% > 90.1) and enrichment factor (EF > 2.7) were evaluated. Finally, this method was successfully used to extract and determine the amount of selected acidic NSAIDs in wastewater samples. The sorbent was cheap, easily prepared, efficient, and even reusable.

Removable dialkoxybenzyl linker for enhanced HPLC purification of peptide hydrazides.

High-performance liquid chromatography (HPLC) plays a crucial role in purifying peptides and proteins and monitoring their reactions. Peptide hydrazides are widely employed intermediates in modern peptide/protein chemistry. However, they often exhibit peak tailing during HPLC purification and analysis. Herein, we describe a dialkoxybenzyl-linker approach to improve HPLC performance in the purification and analysis of peptide hydrazides. A dialkoxybenzyl linker is designed for the solid-phase synthesis of peptide hydrazides, enabling selective cleavage under controlled global deprotection conditions to afford alkylated or free hydrazides. The peptides with this linker exhibit superior HPLC peak shapes, even on degraded columns, compared with those of free hydrazides. In addition, the dialkoxybenzyl linker enhances the overall yield in solid-phase peptide synthesis compared with that achieved using a conventional trityl-based linker. The utility of this linker is validated by the successful synthesis of ubiquitin from three peptide segments using native chemical ligation, achieving higher isolated yields of the peptide segments because of the improved purification efficiency. Thus, this approach is a powerful tool for the synthesis and purification of peptide hydrazides. In conclusion, the dialkoxybenzyl linker enhances HPLC peak symmetry, separation, and solid-phase peptide synthesis yields for peptide hydrazides, providing a practical solution to key purification challenges in peptide chemistry.

Antibiofilm and Anticancer Activity of Multi-Walled Carbon Nanotubes Fabricated with Hot-Melt Extruded Astaxanthin-Mediated Synthesized Silver Nanoparticles.

Multi-walled carbon nanotubes (MWCNTs) were used as carriers for silver nanoparticles (AgNPs). In this process, MWCNTs were coated with mesoporous silica (MWCNT-Silica) for uniform and regular loading of AgNPs on the MWCNTs. In addition, astaxanthin (AST) extract was used as a reducing agent for silver ions to enhance the antioxidant, antibiofilm, and anticancer activities of AgNPs. In this process, AST was extracted from Haematococcus pluvialis (H. pluvialis) and processed by hot melt extrusion (HME) to enhance the AST content of H. pluvialis. AST has strong antioxidative properties, which leads to anticancer activity. In addition, AgNPs are well known for their strong antibacterial properties. The antibiofilm and anticancer effects were studied comprehensively by loading the AST AgNPs onto MWCNT-Silica. AgNPs-loaded MWCNT-silica (MWCNT-Ag) was prepared through the binding reaction of TSD and silanol groups and the aggregation interaction of Ag and TSD. To enhance the antioxidant, antibiofilm, and anticancer activities of AgNPs, HME-treated H. pluvialis extract (HME-AST) was used as a reducing solution of silver ions. The increased AST content of HME-AST was confirmed by high-performance liquid chromatography (HPLC) analysis, and the total phenol and flavonoid content analysis confirmed that HME enhanced the active components of H. pluvialis. The antibiofilm activity of MWCNT-AST was investigated by biofilm inhibition and destruction test, SEM, and CLSM analysis, and the anticancer activity was investigated by WST assay, fluorescent staining analysis, and flow cytometry analysis. MWCNT-AST showed higher antioxidant activity and antibiofilm activity than MWCNT-Ag against E. coli, S. aureus, and methicillin-resistant S. aureus (MRSA). MWCNT-AST showed higher anticancer activity against breast cancer cells (MDA-MB-231) than MWCNT-Ag, and lower toxicity in normal cells HaCaT and NIH3T3. MWCNT-AST exhibits higher antioxidant, antibiofilm, and anticancer activities than MWCNT-Ag, and exhibits lower toxicity to normal cells.

Evaluation of the application of wild yeasts in inhibiting germination of ochratoxin-producing Fungi during coffee fermentation process.

Specialty coffee, typically lightly roasted, is valued for its unique fruity aroma. However, the fermentation process poses a risk of contamination with ochratoxin-producing fungi. This study aimed to select wild yeast strains capable of contributing distinctive flavor profiles while inhibiting the growth of ochratoxin-producing fungi. Coffee pulp served as a substrate to simulate yeast growth during coffee fermentation, allowing for the evaluation of yeast metabolites potential to inhibit spore germination in ochratoxin-producing fungi (Aspergillus niger). The findings demonstrated that the Saccharomyces cerevisiae strain effectively inhibited spore germination in A. niger. High-performance liquid chromatography (HPLC) analysis indicated that citric acid is likely the primary organic acid responsible for inhibiting A. niger spore germination. These results suggested that S. cerevisiae has potential applications in enhancing the food safety of coffee.