Facile green spectrophotometric approaches for the determination of three natural edible antioxidant polyphenols in different matrices

The combination of Curcumin (CRN), resveratrol (RSV), and quercetin (QRN) has significant antioxidant effects and is found to be more effective than a single polyphenol. Spectrophotometric methods are considered one of the most common analytical techniques for the determination of the drugs due to their sensitivity, rapidness, low cost, and reproducibility. Therefore, the presence of new, and simple methods for the determination of such compounds will be highly valuable, specially in the presence of spectral overlap. In this research, five different facile spectrophotometric methods were investigated for the simultaneous determination of that ternary mixture for the first time, including zero order (I), first derivative (II), ratio difference double divisor (III), first derivative ratio spectra (IV), and mean centering (V) methods. The designed approaches were linear over the concentration ranges of (1.0-10.0), (0.5-8.0), and (1.0-14.0) μg/mL, respectively for curcumin, resveratrol, and quercetin. The different methods were then validated as stated by the International Council of Harmonization. The accuracy and precision have been evaluated by statistical analysis including student t-test, variance ratio F-test, and ANOVA. Moreover, the greenness and whiteness of the proposed methods were assessed to ensure the adherence to the greenness characters.

Development of a fluorescent scaffold by utilizing quercetin template for selective detection of Hg2+: Experimental and theoretical studies along with live cell imaging

Quercetin is an important antioxidant with high bioactivity and it has been used as SARS-CoV-2 inhibitor significantly. Quercetin, one of the most abundant flavonoids in nature, has been in the spot of numerous experimental and theoretical studies in the past decade due to its great biological and medicinal importance. But there have been limited instances of employing quercetin and its derivatives as a fluorescent framework for specific detection of various cations and anions in the chemosensing field. Therefore, we have developed a novel chemosensor based on quercetin coupled benzyl ethers (QBE) for selective detection of Hg2+ with "naked-eye" colorimetric and "turn-on" fluorometric response. Initially QBE itself exhibited very weak fluorescence with low quantum yield (Φ = 0.009) due to operating photoinduced electron transfer (PET) and inhibition of excited state intramolecular proton transfer (ESIPT) as well as intramolecular charge transfer (ICT) within the molecule. But in presence of Hg2+, QBE showed a sharp increase in fluorescence intensity by 18-fold at wavelength 444 nm with high quantum yield (Φ = 0.159) for the chelation-enhanced fluorescence (CHEF) with coordination of Hg2+, which hampers PET within the molecule. The strong binding affinity of QBE towards Hg2+ has been proved by lower detection limit at 8.47 µM and high binding constant value as 2 × 104 M-1. The binding mechanism has been verified by DFT study, Cyclic voltammograms and Jobs plot analysis. For the practical application, the binding selectivity of QBE with Hg2+ has been capitalized in physiological medium to detect intracellular Hg2+ levels in living plant tissue by using green gram seeds. Thus, employing QBE as a fluorescent chemosensor for the specific identification of Hg2+ will pave the way for a novel approach to simplifying the creation of various chemosensors based on quercetin backbone for the precise detection of various biologically significant analytes.

In silico and in vivo study of anti-inflammatory activity of Morinda longissima (Rubiaceae) extract and phytochemicals for treatment of inflammation-mediated diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Traditionally, the plant Morinda longissima Y.Z.Ruan (Rubiaceae) is used by ethnic people in Vietnam for the treatment of liver diseases and hepatitis.

AIM OF THE STUDY

The study was designed to assess the efficacy of the 95% ethanolic extract of Morinda longissima roots (MLE) in experimental immune inflammation. The phytochemical variation of root extract and the chemical structures of natural compounds were also investigated using HPLC-DAD-HR-MS analysis.

MATERIALS AND METHODS

Three different doses (100, 200, and 300 mg/kg b.w.) of MLE were chosen to determine anti-inflammatory activity. The mice were given orally extracts and monitored their behavior and mortality for 14 days to evaluate acute toxicity. The volume of the paw and the histopathological evaluation were carried out. The polyphenolic phytoconstituents of MLE extract were identified using LC/MS analysis. The anti-inflammatory efficacy in silico and molecular docking simulations of these natural products were evaluated based on their cyclooxygenase (COX)-1 and 2 inhibitory effects.

RESULTS

This investigation showed the 95% ethanolic extract of Morinda longissima roots was found non-toxic up to 2000 mg/kg dose level in an acute study, neither showed mortality nor treatment-related signs of toxicity in mice. Eight anthraquinones and anthraquinone glycosides of Morinda longissima roots were identified by HPLC-DAD-HR-MS analysis. In the in vivo experiments, MLE was found to possess powerful anti-inflammatory activities in comparison with diclofenac sodium. The highest anti-inflammatory activity of MLE in mice was observed at a dose of 300 mg/kg body weight. The in silico analysis showed that seven out the eight anthraquinones and anthraquinone glycosides possess a selectivity index RCOX-2/COX-1 lower than 1, indicating that these compounds are selective against the COX-2 enzyme in the following the order: rubiadin-3-methyl ether < morindone morindone-6-methyl ether < morindone-5-methyl ether < damnacanthol < rubiadin < damnacanthol-3-O-β-primeveroside. The natural compounds with the best selectivity against the COX-2 enzyme are quercetin (9), rubiadin-3-methyl ether (7), and morindone (4), with RCOX2/COX1 ratios of 0.02, 0.03, and 0.19, respectively. When combined with the COX-2 protein in the MD research, quercetin and rubiadin-3-methyl ether greatly stabilized the backbone proteins and ligands.

CONCLUSION

In conclusion, the anthraquinones and ethanolic extract of Morinda longissima roots may help fight COX-2 inflammation. To develop novel treatments for inflammatory disorders linked to this one, these chemicals should be investigated more in the future.

Theoretical exploration of the phenolic compounds' inhibition mechanism of heterocyclic aromatic amines in roasted beef patties by density functional theory

The ability of spices (bay leaf, star anise, and red pepper) and their characteristic phenolic compounds (quercetin, kaempferol, and capsaicin) to inhibit Heterocyclic aromatic amines (HAAs) in roasted beef patties were compared. Density functional theory (DFT) was used to reveal phenolic compounds interacting with HAAs-related intermediates and free radicals to explore possible inhibitory mechanisms for HAAs. 3 % red chili and 0.03 % capsaicin reduced the total HAAs content by 57.09 % and 68.79 %, respectively. DFT demonstrated that this was due to the stronger interaction between capsaicin and the β-carboline HAAs intermediate (Ebind = -32.95 kcal/mol). The interaction between quercetin and phenylacetaldehyde was found to be the strongest (Ebind = -17.47 kcal/mol). Additionally, DFT indicated that capsaicin reduced the carbonyl content by transferring hydrogen atoms (HAT) to eliminate HO·, HOO·, and carbon-centered alkyl radicals. This study provided a reference for the development of DFT in the control of HAAs.

Chemical profiling of maceration and decoction of Tamarix gallica L. organs and in vitro biological properties

Tamarix gallica L. is a halophytic medicinal shrub traditionally used in the treatment of liver disorders. Leaf and flower infusions are widely used for anti-diarrheic and anti-inflammatory preparations. In this work, we have explored the combined effect of method (Maceration and Decoction) and solvent extraction (70% Methanol, 70% Ethanol, 70% Acetone, and Water) on phenolic composition and biological activities (antioxidant and anti-inflammatory) of different T. gallica organ extracts (Leaves, Flowers, Stems, and Fruits). Obtained results showed that Tamarix leaves reveal more potent antioxidant activity. Methanol (70%) was the best maceration solvent for the extraction of leaves and flowers with high total antioxidant and anti-radical capacities. HPLC analysis showed that catechin, isorhamnetin-3-O-glucoside, isoquercetin were the major phenolics in 70% methanolic extract. Furthermore, this extract showed considerable anti-inflammatory activity. This prospect could be of great importance in the valuation of this halophyte as a source of natural antioxidants and anti-inflammatory drugs.

Development of machine learning models using multi-source data for geographical traceability and content prediction of Eucommia ulmoides leaves

Rapid and scientific quality evaluation is a hot topic in the research of food and medicinal plants. With the increasing popularity of derivative products from Eucommia ulmoides leaves, quality and safety have attracted public attention. The present study utilized multi-source data and traditional machine learning to conduct geographical traceability and content prediction research on Eucommia ulmoides leaves. Explored the impact of different preprocessing methods and low-level data fusion strategy on the performance of classification and regression models. The classification analysis results indicated that the partial least squares discriminant analysis (PLS-DA) established by low-level fusion of two infrared spectroscopy techniques based on first derivative (FD) preprocessing was most suitable for geographical traceability of Eucommia ulmoides leaves, with an accuracy rate of up to 100 %. Through regression analysis, it was found that the preprocessing methods and data blocks applicable to the four chemical components were inconsistent. The optimal partial least squares regression (PLSR) model based on aucubin (AU), geniposidic acid (GPA), and chlorogenic acid (CA) had a residual predictive deviation (RPD) value higher than 2.0, achieving satisfactory predictive performance. However, the PLSR model based on quercetin (QU) had poor performance (RPD = 1.541) and needed further improvement. Overall, the present study proposed a strategy that can effectively evaluate the quality of Eucommia ulmoides leaves, while also providing new ideas for the quality evaluation of food and medicinal plants.

Method development and validation for the quantitative determination of total flavonoids through the complexation of iron (III) and its application in real sample

BACKGROUND

The determination of flavonoids in real sample using UV-Vis spectrophotometer commonly uses quercetin and catechin with Al+3 complexing agent as reference materials for the calibration of the instrument. However, getting these standard materials is challenging due to its expense and unavailability in the chemical reserve of the country. Moreover, the Al+3 - quercetin complexation standard method demands high amount of quercetin in spite of its high cost. Hence, developing alternative method that can solve this problem is crucial for the determination of flavonoids in the real sample.

RESULTS

An iron-based complexation method for the determination of flavonoids in the real sample was developed that reduces the amount of quercetin by 200 times (1 mg/mL to 0.005 mg/mL) during the calibration of UV-Vis spectroscopy as an alternative method. The reaction parameters (incubation time, pH, and concentration of quercetin) were optimized using software Design Expert 11 and confirmed by the practical experiments. The kinetics of reaction between iron and quercetin was found to be pseudo first order with rate constant of kobs at 340 and 510 nm. The analysis window for the flavonoid complex was achieved with the kinetic discrimination of the interferences at its optimized time of complexation 20 min and absorbance maxima of 510 nm. The developed method was validated by evaluating its precision, accuracy, recovery test (84-117%), detection limit and quantification limit following the standard protocols. The calibration of the instrument has been developed for the new method and the linear regression coefficient (R2) of 0.998 was obtained.

SIGNIFICANCE

Applying the developed standard material (Fe3+ - quercetin complex) gives freedom for the analytical chemists to find the standard materials that is accessible and cheaper than the existing one (Al3+-quercetin complex). The developed method can also be easily applied for determination of flavonoid in the real samples without potential interferences coming from sample matrix.

Quantitative analysis of tiliroside and other flavonoid glycosides in Hippophae salicifolia D. Don leaves by HPLC-PDA

A new HPLC-PDA method was developed and validated for simultaneous determination of five phenolic compounds (trans-and cis- isomers of tiliroside, quercetin-3-O-β-D-glucoside, ellagic acid, kaempferol-3-O-β-D-glucoside and isorhamnetin-3-O-glucoside) in the leaves of Hippophae salicifolia D. Don. Of the five compounds, three (tiliroside, quercetin-3-O-β-D-glucoside and ellagic acid) were isolated and characterised by spectroscopy techniques. The developed HPLC method provided a selective, sensitive and rapid analysis with good linearity (r2> 0.999), accuracy and precision. Also, the leaves of H. salicifolia were extracted by three different extraction techniques viz. reflux, microwave and ultrasound. Methanolic extracts prepared by reflux method showed the highest content of all the five compounds.

Covalent conjugation with quercetin mitigates allergenicity of the bee pollen allergen Bra c p in a murine model

Profilin family members are highly conserved food allergens that can cause widespread cross-allergic reactions. Our previous research has demonstrated that the covalent conjunction with quercetin can disrupt the conformational epitopes of a profilin allergen, Bra c p. In this study, we further investigated the intrinsic molecular mechanisms using molecular dynamics simulations. Moreover, the allergenic potential of Bra c p and its conjugate with quercetin was assessed in BALB/c mice. The results showed that continuous interaction with quercetin increased the molecular motion of Bra c p, causing changes to its α-helices and exposing hydrophobic residues which altered antigenic epitopes. Additionally, mice treated with Bra c p-quercetin conjugate showed reduced allergic reactions compared to those treated with Bra c p alone by regulating purine metabolism, calcium signaling, and CD4+CD25+ Tregs proportion. Quercetin conjugation decreases the allergenicity of Bra c p, providing a scientific foundation for reducing the profilin allergens in food.

Liquid chromatography-mass spectrometry-based strategy for systematic profiling of chemical components and associated quantitative analysis of quality markers in Qi-Wei-Tong-Bi oral liquid

Qi-Wei-Tong-Bi oral liquid (QWTB), a famous Chinese medicine preparation composed of seven crude drugs has a good therapeutic effect on rheumatoid arthritis and is widely used in China. However, its chemical composition and quality control have not been comprehensively and systematically investigated. In this study, high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was employed for its chemical profiling. As a result, 100 components were chemically characterized. Additionally, high-performance liquid chromatography coupled with a quadrupole linear ion trap mass spectrometry method was developed to simultaneously quantify nine bioactive components (hyperoside, ononin, quercetin, sinomenine, magnoflorine, gallic acid, protocatechuic acid, monotropein, and cyclo-(Pro-Tyr)) in multiple-reaction monitoring mode. After successful validation in terms of linearity, precision, repeatability, and recovery, the assay method was applied for the determination of 10 batches of QWTB. The results showed that QWTB was enriched in sinomenine and magnoflorine with the highest amount up to hundreds or even thousands of µg/mL, while quercetin, ononin, cyclo-(Pro-Tyr), and hyperoside were much lower with the lowest content below 10 µg/mL. This study work would help to reveal the chemical profiling and provide a valuable and reliable approach for quality evaluation and even pharmacodynamic material basis studies of QWTB.

Phytochemical quantification and HPLC analysis of Parkia speciosa pod extract

INTRODUCTION

Parkia speciosa Hassk., commonly known as bitter bean or twisted cluster bean, is a tropical leguminous plant species native to Southeast Asia. The plant's edible pods have been traditionally used in various cuisines, particularly in Malaysian, Thai, and Indonesian cooking. Apart from being used as a food ingredient, the pods of P. speciosa also have a range of potential applications in other fields, including medicine, agriculture, and industry. The pods are said to have several phytochemicals that hold great therapeutic values such as reducing inflammation, improving digestion, and lowering blood sugar levels. However, there is limited information on the specific phytochemical contents of the pods in the literature. Thus, the aim of this study is to quantify the total phenolic and flavonoid compounds and to determine the concentrations of four selected phytochemical compounds in the P. speciosa pod extract (PSPE).

MATERIALS AND METHODS

Quantification of the total phenolic (TPC) and flavonoid contents (TFC) in PSPE were done via colourimetric methods; and the determination of the concentrations of four specific phytochemicals (gallic acid, caffeic acid, rutin, and quercetin) were done via High- Performance Liquid Chromatography (HPLC).

RESULTS

Colourimetric determination of PSPE showed TPC and TFC values of 84.53±9.40 mg GAE/g and 11.96±4.51 mg QE/g, respectively. Additional analysis of the phytochemicals using HPLC revealed that there were 6.45±3.36 g/kg, 5.91±1.07 g/kg, 0.39±0.84 g/kg, and 0.19±0.47 g/kg of caffeic acid, gallic acid, rutin, and quercetin, respectively.

CONCLUSION

The findings show that PSPE contains substantial amounts of caffeic acid, gallic acid, rutin, and quercetin, which may indicate its potential as antibacterial, anti-inflammatory, anti-lipid, and antiviral medicines.

Antiulcer activity and mechanism of action of the hydroethanolic extract of leaves of Terminalia argentea Mart. In different in vivo and in vitro experimental models

ETHNOPHARMACOLOGICAL RELEVANCE

Terminalia argentea Mart. (Combretaceae) is a deciduous tree commonly found in Brazil, Bolivia, and Paraguay. It occurs in all regions of Brazil and is widespread in the Amazon, Cerrado, Pantanal, Atlantic Rain Forest, and Caatinga Biomes. In the traditional medicine of Brazil, people widely use tea or decoction of its leaf materials for treating gastritis, ulcers, wound healing, and inflammation.

AIM OF THE STUDY

The current study aims to evaluate the gastroprotective and ulcer-healing activities of the hydroethanolic extract of T. argentea leaves (HETa) and investigate the underlying mechanisms of action through in vivo and in vitro experiments.

METHODS

We extracted the leaves of T. argentea with a 70% hydroethanolic solution (HETa) and performed phytochemical analysis using high-performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MSn). We researched the antiulcer activity using in vivo and in vitro experiments, administering three doses (2, 10, and 50 mg/kg) and different concentrations of 1, 5, and 20 μg/mL, respectively. We verified the acute antiulcer activity using chemical models (acidified ethanol (EtOH/HCl) and indomethacin (IND)) and physiological models (water-immersion stress (WRS)). To induce chronic ulcers, used acetic acid and treated the animals for seven days. To investigate the mechanism of action, conducted assays of antioxidant activity, measured the dosage of inflammatory cytokines, quantified mucus, treated with inhibitors (IND, L-NAME, glibenclamide, and yohimbine), performed histopathological analysis, and measured gastric acid secretion. Furthermore, we performed in vitro experiments on murine macrophage cell lines (RAW 264-7 cells) to quantify nitrite/nitrate and cytokine production and on V79-4 cells to verify cell proliferation/migration.

RESULTS

We conducted HPLC and ESI-MSn analyses to obtain a fingerprint of the chemical composition of the HETa, revealing the presence of phenolics (caffeoyl ellagic acid), flavonoids (rutin, quercetin xyloside, quercetin rhamnoside, quercetin glucoside, quercetin galloyl xyloside, quercetin), and tannins (terminalin), respectively. The three doses of HETa reduced acute and chronic ulcers in different models. The mechanism of action involves increasing mucus production and angiogenesis, and it partially involves prostaglandins, nitric oxide, K+ATP channels, and α2-adrenergic receptors. HETa also exhibited antioxidant potential, reducing myeloperoxidase (MPO) activity, and increasing glutathione (GSH) levels. Moreover, it demonstrated anti-inflammatory action by reducing nitrite/nitrate levels and pro-inflammatory cytokine concentrations in vivo, and it increased in vitro proliferation/migration of fibroblasts.

CONCLUSIONS

The study shows that HETa presents a potent preventive and curative antiulcer effect in different ulcer models, supporting the popular use of homemade preparations of T. argentea leaves. The preventive and gastric healing ulcer activity of HETa involves multiple targets, including increasing the gastric mucus barrier, antioxidant defenses, and anti-inflammatory effects on gastric mucosa repair. Phytochemical analysis identified the presence of phenolic compounds, flavonoids, and tannins in HETa, and the antiulcer activity may be attributable to the combined effect of these constituents.

Divergent metabolism of two lychee (Litchi chinensis Sonn.) pulp flavonols and their modulatory effects on gut microbiota: Discovery of hydroxyethylation in vitro colonic fermentation

Quercetin 3-O-rutinose-7-O-α-l-rhamnoside (QRR), a characteristic lychee pulp flavonoid, has been linked to diverse bioactivities involving microbial metabolism. By integrating colonic fermentation and mass spectrometry, the catabolites including 7-O-hydroxyethyl-isorhamnetin and 3'-amino-4'-O-methyl-7-O-hydroxyethyl-isorhamnetin were unprecedently identified and unique to QRR metabolism, relative to the structural analog quercetin 3-O-rutinoside (QR) metabolism. These above-described metabolites highlighted a special biotransformation hydroxyethylation in QRR catabolism. QRR was partially deglycosylated into quercetin 3-O-glucoside-7-O-α-l-rhamnoside potentially catalyzed by Bacteroides. QR was more directly degradable to aglycone during colonic fermentation than are QRR. Unlike with QR fermentation, equivalent QRR effectively upregulated concentrations of propionic and butyric acids that were highly relevant with Faecalibacterium and Coprococcus. After fermentation, the relative abundances of Bacteroides uniformis (0.03%) and Akkermansia muciniphila (0.13%) were only upregulated by QRR among all fermentation groups, leading to the enrichments of the corresponding genera. These results further reveal the relationship between flavonoid structures and metabolic characteristics.

Simultaneous determination of three curative flavonoids and neurotoxic anisatin in star anise fruits by ultra-high performance liquid chromatography-tandem mass spectrometry

Chinese star anise is an anise-scented star-shaped fruit of the evergreen Illicium verum tree. It is generally used as a spice and folk medicine for treating digestive illness. Chinese star anise may be adulterated with Japanese star anise (fruit of Illicium anisatum tree with similar morphology to the former), containing high content of toxic anisatin leading to severe physical disorders. In this work, a UHPLC-MS/MS method has been developed to determine three quality markers (quercetin, kaempferol, and luteolin) and toxicity marker (anisatin) of star anise using quercetin-d3, an exogenous heavy isotopic compound, as internal standard. Chromatographic separation of quality and toxicity marker compounds was achieved using a T3 column within two minutes. The method was successfully developed, validated, and used to quantify the multiple marker compounds in both botanical reference materials and star anise samples. This method can be used for quality control and assessment of Chinese star anise products.

Quantitative-HPLC-DAD polyphenols analysis, anxiolytic and cognition enhancing potentials of Sorbaria tomentosa Lindl. Rehder

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants of the family Rosaceae have a long history of traditional uses in the management of neurological disorders. Sorbaria tomentosa Lindl. Rehder is composed of antioxidant and neuroprotective polyphenolics.

AIMS OF THE STUDY

The current study was designed to explore phenolics profile via high performance liquid chromatography-photodiode array detector (HPLC-DAD) and validated the neuroprotective and anxiolytic potentials of S. tomentosa by applying in vitro and in vivo approaches.

MATERIALS AND METHODS

The plant crude methanolic extract (St.Crm) and fractions were subjected to HPLC-DAD analysis for qualitative and quantitative assessment of phytochemicals. Samples were screened for in vitro free radicals scavenging assays by using 2,2-diphenylpicrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) along with acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibition assays. For cognitive and anxiolytic studies, mice were subjected to open field, elevated plus maze (EPM), light-dark model, Y-maze, shallow water maze (SWM), and novel object recognition (NOR) tests.

RESULTS

HPLC-DAD analysis revealed the presence of high concentrations of phenolic compounds. For instance, in St.Cr, 21 phenolics were quantified, among which apigenin-7-glucoside (291.6 mg/g), quercetin (122.1 mg/g), quercetin-3-feruloylsophoroside-7-glucoside (52.6 mg/g), quercetin-7-glucoside (51.8 mg/g), ellagic acid (42.7 mg/g), luteolin (45.0 mg/g), kaempferol (40.5 mg/g), 5-feruloylquinic acid (43.7 mg/g) were present in higher concentrations. Likewise, in ethyl acetate fraction (St.Et.Ac), 21 phenolics were identified as 3,5-di-caffeoylquinic acid (177.4 mg/g) and 5-hydroxybenzoylquinic acid (46.9 mg/g) were most abundant phytochemicals. Highly valuable phenolics were also identified in other fractions including butanol (St.Bt), chloroform (St.Chf), and n-hexane (St.Hex). The various fractions exhibited concentration dependent inhibition of free radicals in DPPH and ABTS assays. Potent AChE inhibitory potentials were revealed by the test samples with St.Chf, St.Bt and St.EtAc being the most active having an IC50 of 298.1, 580.1, and 606.47 μg mL-1, respectively. Similarly, St.Chf, St.Bt, St.EtAc and St.Cr exhibited potent BChE inhibitory activity and was observed as 59.14, 54.73, 51.35 and 49.44%, respectively. A significant improvement in the exploratory behavior was observed in open field test and stress/anxiety was relieved effectively at 50-100 mg/kg. Likewise, EPM, light-dark and NOR tests revealed an anxiolytic and memory enhancing behaviors. These effects were further corroborated from the Y-maze and SWM transgenic studies that showed considerable improvement in cognition retention.

CONCLUSIONS

These findings concluded that S. tomentosa possessed potential anxiolytic and nootropic efficacies and may have therapeutic potential in neurodegenerative disorders.

Assessment of the anti-inflammatory and analgesic effects of Opuntia ficus indica L. Cladodes extract

This study aimed to evaluate the anti-inflammatory and analgesic properties of the methanolic extract of Opuntia ficus indica L. in small animal (rats and mice model). The current treatment for febrile conditions often involves the use of non-steroidal anti-inflammatory drugs (NSAIDs), which can have adverse effects, particularly gastrointestinal ulcers. Therefore, there is a growing need to explore natural alternatives with fewer side effects. The study utilized various experimental models to assess the effects of the extract. The results demonstrated a significant analgesic effect of the extract, as evidenced by a reduction in pain induced by acetic acid and hot plate tests. Additionally, the extract exhibited anti-inflammatory effects, as indicated by a decrease in carrageenan-induced paw edema and dextran-induced inflammation. To gain insights into the chemical composition of the extract, HPLC analysis was conducted. The analysis successfully identified and quantified 20 compounds, including luteolin, galangin, catechin, thymol, methylated quercetin, quercetin, rutin, acacetin, hesperidin, apigenin, kaempferol, pinocembrin, chrysin, gallic acid, caffeic acid, ascorbic acid, ferulic acid, m-coumaric acid, rosmarinic acid, and trans-cinnamic acid.The findings suggest that Opuntia ficus indica L. extract holds promise as an effective and reasonably priced natural remedy for pain and inflammation in rats and mice model. The comprehensive chemical composition analysis provided valuable insights into the presence of various bioactive compounds, which may contribute to the observed therapeutic effects. Further research and exploration of the extract's mechanisms of action are warranted to fully understand its potential in small animal healthcare.

Effect of different oil extraction methods on bioactive compounds, antioxidant capacity and phytochemical profiles of raw flaxseeds (Linum usitatissimum) and after roasting at different temperatures

BACKGROUND

Factors such as variety, genetics, soil structure and plant diseases affect the oil amount and properties of flaxseed. By applying heat and various extraction treatments to flaxseed, the storage ability of the seed is increased by the removal of moisture, and the stability of phytochemicals in the seed against heat can be determined.

RESULTS

Total carotenoid and phenol of flaxseeds changed from 0.13 (control) and 0.61 mg g-1 (120 °C) to 202.64 (control and 90 °C) and 225.69 mg 100 g-1 (120 °C), respectively. While total flavonoid of flaxseed roasted at different temperatures varied between 636.0 (90 °C) and 786.00 mg 100 g-1 (120 °C), antioxidant activity values for raw and roasted flaxseeds between 59.32% (control) and 68.64% (120 °C) were recorded. Oil content of seeds changed between 34.07 and 42.57% (P < 0.05). Viscosity of flaxseed oil extracted using different systems was between 31.95 (cold-pressed; control) and 36.00 mPa s (ultrasonic; 120 °C). The dominant phenolics of flaxseeds were identified as isorhamnetin, resveratrol, quercetin, catechin, apigenin-7-glucoside and campherol. The oils of flaxseeds contained 55.27-58.23 linolenic, 17.40-18.91 oleic, 14.03-14.84 linoleic and 4.97-5.37 palmitic acids, depending on extraction method and roasting temperature.

CONCLUSION

Roasting and oil extraction methods did not have a significant effect on free acidity, but was found to affect peroxide value. The predominant phenolic constituents of flaxseed samples were isorhamnetin, resveratrol, quercetin, catechin, apigenin-7-glucoside and campherol, respectively. The major fatty acids of flaxseed oil were determined as linolenic, oleic, linoleic and palmitic. © 2023 Society of Chemical Industry.

Iridoid- and flavonoid-enriched fractions of Cornus sanguinea and Cornus mas exert antioxidant and anti-inflammatory effects and inhibit key enzymes in the treatment of metabolic disorders

Background: Berry fruits are recognized as a "superfood" due to their high content of bioactive compounds and health benefits. Scope and approach: Herein, extracts of Cornus sanguinea and Cornus mas fresh and dried fruits obtained by different extraction procedures (ethanolic and hydroalcoholic maceration, ultrasound-assisted extraction, and Soxhlet apparatus) were analysed using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS) and compared to identify the main healthy compounds and their impact on the inhibition of key enzymes (pancreatic lipase, α-glucosidase, and α-amylase) associated with metabolic disorders. The antioxidant activity and inhibition of nitric oxide (NO) and NF-κB pathway were also investigated. Key findings and conclusions: Flavonoids, iridoids, and phenolic acids were the main classes of identified compounds. Herein, kaempferol 3-O-galactoside, kaempferol 3-O-glucoside, quercetin, quercetin 3-O-xyloside, and myricetin 3-O-galactoside were detected for the first time in C. sanguinea. Remarkable antioxidant effects and promising α-glucosidase and lipase inhibitory activity were observed with extracts obtained by hydroalcoholic maceration of both Cornus dried fruits. Consequently, these extracts were subjected to fractionation using Amberlite XAD-16 resin. The most promising biological activities, which are attributed to the presence of some flavonoids and iridoids, were detected with the C. sanguinea fractions, in particular SD2(II). The results of this study offer new insights into the potential development of functional foods, nutraceuticals, and food supplements using the Cornus species.

Development of the paper-based colorimetric sensor for simple and fast determination of quercetin in guava leaf extract

This present study aimed to develop a paper-based colorimetric sensor in the form of paper-microzone plates (PµZP), for simple and fast quercetin determination in guava leaf extract samples. Here, N-bromosuccinimide (NBS) solution was immobilized on the microzone as a sensing probe, where quercetin solution can be dropped on it to form red-purplish color adducts which can be seen by the naked eye or captured using a flatbed scanner. The color intensity of the microzone can be quantified against a blank solution and used as analytical data in scanometric assay. The sensor showed a response time of 8 min, a linear interval of 1-10 mM with a detection limit at 1.274 mM toward quercetin, and exhibited good reproducibility (RSD < 1%) and accuracy (98-99% recovery). The quercetin level of guava leaf extract determined by the PµZP-scanometric method was found comparable with that of the TLC-densitometric method, suggesting its use as an alternative method for quercetin analysis in the guava leaf extract.

Capillary surface modification using millimolar levels of aminosilane reagent for highly efficient separation of phenolic acids and flavonols by capillary electrophoresis with UV detection

INTRODUCTION

Phytochemical analysis of phenolic acids and flavonols poses a challenge, necessitating the development of an efficient separation method. This facilitates the quantification of these compounds, yielding valuable insights into their benefits.

OBJECTIVE

To develop a highly effective separation of phenolic acids and flavonols by capillary electrophoresis and ultraviolet (UV) detection through the modification of the capillary surface using 3-aminopropyltriethoxysilane (APTES) at millimolar concentrations.

METHODS

The capillary surface is modified with 0.36 mM-APTES solution. The electrolyte is 20.0 mM borate buffer (pH 9.0). Separation performance (plate number N, resolution Rs ), stability, and reproducibility of the coating procedure are evaluated using the analysis of phenolic acids, rutin and quercetin.

RESULTS

The modified capillary provided efficient separation with plate numbers N ≥ 1.0 × 104  m-1 and resolution Rs ≥ 0.8 for all pairs of adjacent peaks of the separation of five selected phenolic acids, rutin, quercetin, caffeine and methylparaben (as internal standard). The precisions of the relative migration times for 17 consecutive analyses of samples over 3 h were 1% relative standard deviation (RSD) for rutin and 7% RSD for quercetin. The analysis of rutin and quercetin in 12 dietary supplement product samples only required a simple dilution step for sample preparation.

CONCLUSION

A straightforward modification technique utilising millimolar concentrations of APTES resulted in highly efficient separation of phenolic acids, rutin and quercetin, accompanied by high precision and surface stability. The modified capillary proved successful in analysing rutin and quercetin content in dietary supplements.

Physico-chemical, microbiological, and sensory characteristics of yogurt as affected by various ingredients

l-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-d-glucosamine, licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut. The purpose of this research was to explore the impact of these functional ingredients on the physico-chemical, microbiological, and sensory properties of yogurt. The milk from same source was equally divided into 9 pails and the 8 ingredients were randomly assigned to the 8 pails. The control had no ingredient. Milk was fermented to yogurt. The pH, titratable acidity, syneresis, viscosity, color (L*, a*, b*, C*, and h*), Streptococcus thermophilus counts, and Lactobacillus delbrueckii spp. bulgaricus counts of yogurts were determined on d 1, 7, 14, 21, 28, 35, and 42, whereas coliform counts, yeast and mold counts, and rheological characteristics were determined on d 1 and 42. The sensory study was performed on d 3 and particle size of the functional ingredients (powder form) was also determined. When compared with control, the incorporation of slippery elm bark into yogurts led to less syneresis. l-Glutamine increased pH and n' values (relaxation exponent derived from G') and lowered titratable acidity values. N-Acetyl-d-glucosamine incorporation resulted in higher n' and lower titratable acidity values, whereas maitake mushroom led to lower n' values. Incorporating quercetin increased the growth of L. bulgaricus. Adding maitake mushrooms increased the growth of S. thermophilus but lowered apparent viscosity values, whereas quercetin decreased its S. thermophilus counts. Quercetin decreased L* and a* values but increased b* values, and maitake mushroom increased a* values. Thixotropic behavior increased with the addition of licorice root and quercetin. Adding slippery elm bark, N-acetyl-d-glucosamine, licorice root, maitake mushrooms, and zinc orotate into yogurt did not affect the sensory properties, whereas yogurts with quercetin had the lowest sensory scores. Overall, most of these ingredients did not cause major changes to yogurt properties.

Ultrasonic-assisted extraction of fenugreek flavonoids and its geographical-based comparative evaluation using green UHPLC-DAD analysis

BACKGROUND

This study, for the first time, reports a simultaneous determination of flavonoids; rutin (RT), quercetin (QT), luteolin (LT), and kaempferol (KF) in different origins of fenugreek seeds samples (N = 45) using a green UHPLC-DAD analysis METHODOLOGY: Ultrasound-assisted extraction (UAE) was employed to extract fenugreek flavonoids using different polarity solvents of n-hexane (n-hex), dichloromethane (DCM), and methanol (MeOH) RESULTS: The extract yield on an individual basis was observed in the range of 1.03-17.29 mg, with the highest yield (mg/sample) for the Egyptian sample (17.29 mg). The highest total extract yield (mg/origin) was observed for the Iranian sample (82.28 ± 5.38). The solvent with the highest extract yield (mg) was n-hex 169.35 ± 13.47, followed by MeOH 114.39 ± 12.27. The validated green UHPLC-DAD method resulted in a short runtime (9 min) with an accuracy of 97.86(±12.32)-101.37(±5.91), r2-values = 0.993-0.999, LOD = 2.09-4.48 ppm, and LOQ = 6.33-13.57 ppm for flavonoids analysis within the linearity range of 1-500 ppm. The general yield for flavonoids exhibited a descending order (ppm): RT (2924.55 ± 143.84) > QT (457.05 ± 34.07) > LT (82.37 ± 3.27) > KF (4.54 ± 0.00). The yield (ppm) for the flavonoids was more in MeOH solvent (3424.81 ± 235.44) constructing a descending order of MeOH > n-hex > DCM. For an individual flavonoid yield; MeOH was seen with an order of RT > QT > LT, n-hex (LT > QT), and DCM (RT > LT > QT). The statistical analysis of PCA (principle component analysis) revealed a widespread distribution of flavonoids in fenugreek seeds with a variance of 35.93% (PC1). Moreover, flavonoids extraction was prone to the nature and specificity of the solvent used (PC2: 33.34%) rather than the amount of the extract yield (P = 0.00). The K-mean cluster analysis showed the origins with higher flavonoids yield in appropriate solvent as I3M (Indian accession # 3 MeOH extract) with more QT amount, IR2M (Iranian accession # 2 MeOH extract) with more LT amount along with I2M (Indian accession # 2 MeOH extract) and Q2M (Qassim Saudi Arabia accession # 2 MeOH extract) containing high amount of RT. The outcomes are supported by KMO (Kaiser-Meyer-Olkin) and Bartlett's test value of 0.56 with X2-value of 191.87 (P = 0.00) CONCLUSION: The samples were effectively evaluated and standardized in terms of flavonoid amount suggesting a significant variation in fenugreek quality.

Deciphering the fluorescence quenching potential of Croton bonplandianum leaves and detection of bioactive molecules using liquid chromatography and mass spectrometry

In this study, liquid chromatography and mass spectrometry were used to screen the active phytochemicals and analyze antioxidant activity of Croton bonplandianum. In addition, cadmium telluride quantum dots were used to analyze the fluorescence quenching capabilities of Croton bonplandianum plants. UPLC-ESI-MS was used to screen polyphenols in the mass range of 100-2000, with both positive and negative ionizations. Based on molecular weight, 7-Spirostanoldihexoside isomer, Rutin, Quercetin hexoside, Kaempferol-3-O-(p-coumaroyl)-glucoside, Kaempferol, Quercetin, and (E) Catechin-(E) Gallocatechin were tentatively identified. In total, 63.34 mg of polyphenols and 20.36 mg of flavonoids were detected. Lipid peroxidation IC₅₀ values were 212, 38, 56, and 365 g/mL for DPPH, ABTS, and superoxide radicals. Reducing power of the plant material showed the maximum absorbance of 0.56 in 500 μg/mL concentration. Furthermore, the plant extract quenched cadmium telluride quantum dots fluorescence in a dose dependent manner. The results from quenching concluded that Croton bonplandianum with QDs might be used as a drug targeting and delivery nanomaterial.

The Phenolic Compounds' Role in Beer from Various Adjuncts

BACKGROUND

The present article considers the influence of malt with various adjuncts on beer organic compounds and taste profile composition, with more attention paid to the phenol complex change. The topic under consideration is relevant since it studies the interactions of phenolic compounds with other biomolecules, and expands the understanding of the adjuncts organic compounds contribution and their joint effect on beer quality.

METHODS

Samples of beer were analyzed at a pilot brewery using barley and wheat malts, barley, rice, corn and wheat, and then fermented. The beer samples were assessed by industry-accepted methods and using instrumental analysis methods (high-performance liquid chromatography methods-HPLC). The obtained statistical data were processed by the Statistics program (Microsoft Corporation, Redmond, WA, USA, 2006).

RESULTS

The study showed that at the stage of hopped wort organic compounds structure formation, there is a clear correlation between the content of organic compounds and dry substances, including phenolic compounds (quercetin, catechins), as well as isomerized hop bitter resines. It is shown that the riboflavin content increases in all adjunct wort samples, and mostly with the use of rice-up to 4.33 mg/L, which is 9.4 times higher than the vitamin levels in malt wort. The melanoidin content in the samples was in the range of 125-225 mg/L and its levels in the wort with additives exceeded the malt wort. Changes in β-glucan and nitrogen with thiol groups during fermentation occurred with different dynamics and depending on the adjunct's proteome. The greatest decrease in non-starch polysaccharide content was observed in wheat beer and nitrogen with thiol groups content-in all other beer samples. The change in iso-α-humulone in all samples at the beginning of fermentation correlated with a decrease in original extract, and in the finished beer there was no correlation. The behavior of catechins, quercetin, and iso-α-humulone has been shown to correlate with nitrogen with thiol groups during fermentation. A strong correlation was shown between the change in iso-α-humulone and catechins, as well as riboflavin and quercetin. It was established that various phenolic compounds were involved in the formation of taste, structure, and antioxidant properties of beer in accordance with the structure of various grains, depending on the structure of its proteome.

CONCLUSIONS

The obtained experimental and mathematical dependences make it possible to expand the understanding of intermolecular interactions of beer organic compounds and take a step toward predicting the quality of beer at the stage of using adjuncts.

Antioxidant and Antiproliferative Activities of Kale (Brassica oleracea L. Var. acephala DC.) and Wild Cabbage (Brassica incana Ten.) Polyphenolic Extracts

Brassicaceae are rich in healthy phytochemicals that have a positive impact on human health. The aim of this study was to analyze the phenolic compounds and antioxidant and anticancer potential of traditional Croatian kale (Brassica oleracea L. var. acephala DC.) and wild cabbage (Brassica incana Ten.) extracts. The phenolic groups and antioxidant activity were determined by spectrophotometry, selected phenolic compounds (ferulic acid, sinapic acid, salicylic acid, kaempferol, and quercetin) were analyzed by LC-MS/MS, and anticancer potential was evaluated in vitro using HeLa cells. The extracts of both plant species are rich in phenolic compounds and showed significant antioxidant activity at similar levels. LC-MS/MS detected sinapic acid as the most abundant phenolic acid, followed by ferulic acid, while salicylic acid was present at lower concentrations. A comparative analysis showed that wild cabbage contained significantly more sinapic acid, while kale contained more kaempferol and quercetin. Both Brassica extracts at a concentration of 50 µg mL^-1 showed an antiproliferative effect on HeLa cells, while they did not affect the proliferation of normal human skin fibroblasts. Wild cabbage extract also showed an antiproliferative effect on HeLa cells at a lower applied concentration of 10 µg mL^-1 of extracts. The clonogenic analysis also revealed the inhibitory effect of the extracts on HeLa colony growth.