The UHPLC-QTOF-MS Phenolic Profiling and Activity of Cydonia oblonga Mill. Reveals a Promising Nutraceutical Potential

Herbicidal Activity and Metabolic Profiling of Piper tuberculatum Jacq. Leachates

Understanding how allelochemicals with herbicidal activity are released in plant interactions is key to developing sustainable weed control strategies. This study aimed to investigate the herbicidal activity and metabolic profile of Piper tuberculatum Jacq. leachates. In vitro bioassays were performed with P. tuberculatum leaf leachates to evaluate their effects on the germination and early growth of Bidens bipinnata L. and Digitaria insularis (L.) Fedde. (DIGIN.). The leachate extracts were subsequently characterized via liquid chromatography high-resolution mass spectrometry-based metabolomics and molecular networking. The results showed that weed germination and seedling development were significantly affected by the P. tuberculatum leachates. Metabolomic analysis revealed that allelochemicals belonging to the classes of alkaloids, fatty acids, phenolic compounds, steroids, and terpenoids are potentially involved in herbicidal activity. These findings suggest that P. tuberculatum could be explored as a natural alternative for sustainable weed management, potentially reducing the dependence on synthetic herbicides.

Saber F, K. Arafa R, Schiano Moriello A, A. Rasle R, Soria‐Lopez A, G. Abd EL‐Gawwad S, Rocchetti G, Otero P, Kulinowski Ł, Skalicka‐Woźniak K, Lucini L, Simal‐Gandara J. The Phenolic Signature of Psidium cattleianum Fruits and Leaves Modulates TRPV1 and TRPA1 Transient Receptor Potential Channels: A Metabolomics, In Vitro, and In Silico Study

Although Psidium cattleianum (strawberry guava, Myrtaceae) is known for its anti-inflammatory, antioxidant, antimicrobial, and antidiabetic properties, its phytochemical profile and associated bioactivities remain largely underexplored. This study employed UHPLC-QTOF-HRMS for untargeted phenolic profiling of leaf and fruit extracts from P. cattleianum, followed by semi-quantification of phenolic subclasses and multivariate data analysis. Four hundred sixty-nine metabolites, including various phenolic subclasses-predominantly flavonoids and phenolic acids were- identified and annotated. Using HEK-293 cells stably transfected with TRPA1 or TRPV1 cation channels, it was found that both leaf and fruit extracts activate and rapidly desensitize TRPA1 in a concentration-dependent manner (EC50 18 and 30 μg/mL; IC50 60 and 47 μg/mL, respectively). Additionally, molecular docking analysis provided deeper insights into the interactions between P. cattleianum phytochemicals and the TRPA1 cation channel, identifying theaflavin 3,3'-O-digallate as the phenolic compound with the highest affinity (S score of -9.27 Kcal/mol). Interestingly, except for theaflavin 3,3'-O-digallate, compounds enriched in the leaf extract exhibited weaker binding interactions and lower S scores (approximately -7 Kcal/mol) compared to those enriched in the fruit extract. Also, a 100 ns molecular dynamics study of theaflavin 3,3'-O-digallate with TRAP1 demonstrated high binding stability of the complex. Overall, this study offers valuable insights into the phytochemical characteristics of P. cattleianum extracts and reveals their mechanism of action through affinity for the TRPA1 cation channel-receptors.

Genetic diversity and population structure of Bael [Aegle marmelos (L.) Correa] genotypes using molecular markers in the North-Western plains of India

Bael is a fruit crop that is extensively distributed throughout South-East Asia and is underutilized in medicine. The potential applications of bael's therapeutic and nutritional qualities in diverse ethnic communities are enormous. This study focuses on evaluating the morpho-pomological and molecular characteristics, utilizing SSR markers, of 80 wild bael genotypes alongside the NB-5 and NB-9 cultivars, derived from the North Western plains of India. Based on the evaluated morpho-pomological features, substantial variations were found between all genotypes. The fruit's inner diameter and pulp weight varied from 4.41 to 11.54 cm and 34.63 to 786.41 g, respectively. Numerous variations in the genotypes were observed in the shell weight/fruit, fruit skull thickness and fruit yield/plant. The bael fruit mucilage's total soluble solids (TSS) and total sugar content varied from 40.10 to 49.60 obrix and 8.11 to 21.17%, respectively. Using ward cluster analysis, the genotypes were divided into two primary clusters. Among the bael genotypes, the population structure analysis identified three subpopulations. SSR markers are used to measure genetic variety; of the 27 polymorphic markers, 17 show allelic diversity between genotypes. Molecular genetic diversity analysis, on the other hand, highlighted the genotypes genetic distinctiveness by classifying them into three major clusters. These findings offer valuable insights into the rich diversity and intricate interactions among the bael genotypes under investigation, paving the way for more strategic future breeding and selection efforts to elevate the quality of this remarkable fruit.

Metabolomic Profiles and Biopharmaceutical Properties of Petrosimonia brachiata and P. nigdeensis from Turkey

Halophytic plants possess a huge range of active constituents and medicinal benefits. In this study, extracts (water, ethanol, ethyl acetate, dichloromethane, and n-hexane) of two halophytes of the genus Petrosimonia (P. brachiata and P. nigdeensis) were investigated for their phytochemical profiles and pharmacological properties. The phytochemical profiles of both species were investigated using an untargeted metabolomics approach based on high-resolution mass spectrometry. The two species show different polyphenolic profiles and these are influenced by the different extraction solvents used. The same extracts were used for different bioactivity assays. The results show that all extracts yielded total flavonoid and phenolic contents of 11.14-24.22 mg GAE/g and 3.15-22.03 mg RE/g, respectively. While extracts of both species demonstrated a radical scavenging ability in the ABTS assay (16.12-98.02 mg TE/g), only the polar and moderately polar extracts (water, ethanol, and ethyl acetate) showed scavenging potential in the DPPH assay (4.74-16.55 mg TE/g). A reducing potential was also displayed by all extracts in the CUPRAC and FRAP assays (26.02-80.35 mg TE/g and 31.70-67.69 mg TE/g, respectively). The total antioxidant capacity of the extracts ranged from 0.24 to 2.17 mmol TE/g, and the metal chelating activity ranged from 14.74 to 33.80 mg EDTAE/g. The water extracts possessed a higher metal chelating power than the other extracts. All extracts acted as inhibitors of acetylcholinesterase (0.16-3.85 mg GALAE/g) and amylase (0.11-1.28 mmol ACAE/g). Moreover, apart from the water extracts, the other extracts also showed anti-butyrylcholinesterase activity (0.73-2.86 mg GALAE/g), as well as anti-tyrosinase (36.74-61.40 mg KAE/g) and anti-glucosidase (2.37-2.73 mmol ACAE/g) potential. In general, the water extracts were found to be weak inhibitors of the tested enzymes, while the ethanol extracts mostly showed an inhibitory effect. The obtained findings revealed the antioxidant and enzyme inhibitory properties of these two species and demonstrated that the solvent type used affected the pharmacological properties of the extracts and hence, can be useful to further investigate the active constituents yielded in the extracts and understand the mechanisms involved.

Behavior, antioxidant, and metabolomics effects of Allium tuncelianum

Allium species are consumed extensively as folkloric medicine and dietary elements, but limited studies have been conducted on them. In this study, the effects of an ethanol-water extract obtained from the underground bulb of Allium tuncelianum (Kollmann) Özhatay, B. Mathew & Şiraneci (AT) on the behavioral, antioxidant, and metabolite parameters in rats were evaluated. AT was administered orally once a day at doses of 100 and 400 mg/kg to male Wistar albino rats for 10 consecutive days. The elevated plus maze, rotarod, and hotplate tests were used to examine anxiety-like behaviors, locomotor activities, and pain perception in the rats, respectively. Additionally, untargeted metabolomic analyses were performed on plasma samples and AT extracts using two orthogonal analytical platforms. The phenolic components, mainly fumaric acid, malic acid, vanillic acid, quercetin-3-arabinoside, hydrocinnamic acid, and gallocatechin, were determined in the extract. In addition, arbutin, salicylic acid, trehalose, and nicotinic acid were analyzed in the extract for the first time. The AT extract did not decrease the catalase, glutathione peroxidase, or superoxide dismutase levels; however, diazepam decreased some of those parameters significantly in the brain, liver, and kidney. Although both the AT and diazepam treatments resulted in an increase in anxiolytic-like effects compared to the control group, no significant differences were observed (p > .05). In the metabolomic analysis, significant changes were observed in the rats treated with AT and diazepam, and they caused significant changes in some metabolic pathways, including amino acid and fatty acid metabolism, compared to the control.

Antioxidant activity and Inhibitory effects of Cydonia oblonga Miller. leaves extracts against calcium oxalate stones

Urinary stone disease is a widespread health problem in both adults and children, and its prevalence has been increasing worldwide. Various plants preparations have already been used since ancient times in order to treat urolithiasis. The aim of this study is to evaluate the antioxidant capacity and litholytic effect on kidney stones of Cydonia oblonga Miller. leaves. The infusion, methanol and acetone extracts were made from Cydonia oblonga Miller. leaf at different concentration. Estimation of mass fractions of total polyphenol, flavonoid, and flavonol contents, as well as the in vitro radical scavenging potential on 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH·) of the investigated extracts was carried out using colorimetric methods. The litholytic property of the extracts was performed by an in-vitro model using experimentally prepared kidney stones- calcium oxalate. As results, the quince leaf extracts revealed stronger antioxidant properties in the DPPH assay, which was proved by the semi-maximal inhibitory concentration values, being about 36.06 ± 3.55, 74.15 ± 6.29, and 142.35 ± 5.09 µg/ml for methanol, acetone and infusion extracts respectively. Furthermore, the tested extracts were found to be more effective in dissolving calcium oxalate stones compared to the control solutions, the mass loss is about 15.13 ± 1.10% with methanol extract, while it is 14.77 ± 1.74% and 11.14 ± 2.86% for acetone and infusion extracts respectively. These findings confirm the quince leaf's richness in phyto-components, offering anti-oxidant property and being able to be used as a remedy for the management of kidney stones by dissolving calcium oxalate stones in the kidneys.

Pulp or Peel? Comparative Analysis of the Phytochemical Content and Selected Cosmetic-Related Properties of Annona cherimola L., Diospyros kaki Thumb., Cydonia oblonga Mill. and Fortunella margarita Swingle Pulp and Peel Extracts

Fruit peels might be a valuable source of active ingredients for cosmetics, leading to more sustainable usage of plant by-products. The aim of the study was to evaluate the phytochemical content and selected biological properties of hydroglycolic extracts from peels and pulps of Annona cherimola, Diospyros kaki, Cydonia oblonga, and Fortunella margarita as potential cosmetic ingredients. Peel and pulp extracts were compared for their antiradical activity (using DPPH and ABTS radical scavenging assays), skin-lightening potential (tyrosinase inhibitory assay), sun protection factor (SPF), and cytotoxicity toward human fibroblast, keratinocyte, and melanoma cell lines. The total content of polyphenols and/or flavonoids was significantly higher in peel than in pulp extracts, and the composition of particular active compounds was also markedly different. The HPLC-MS fingerprinting revealed the presence of catechin, epicatechin and rutoside in the peel of D. kaki, whereas kaempferol glucoside and procyanidin A were present only in the pulp. In A. cherimola, catechin, epicatechin and rutoside were identified only in the peel of the fruit, whereas procyanidins were traced only in the pulp extracts. Quercetin and luteolinidin were found to be characteristic compounds of F. margarita peel extract. Naringenin and hesperidin were found only in the pulp of F. margarita. The most significant compositional variety between the peel and pulp extracts was observed for C. oblonga: Peel extracts contained a higher number of active components (e.g., vicenin-2, kaempferol rutinoside, or kaempferol galactoside) than pulp extract. The radical scavenging potential of peel extracts was higher than of the pulp extracts. D. kaki and F. margarita peel and pulp extracts inhibited mushroom and murine tyrosinases at comparable levels. The C. oblonga pulp extract was a more potent mushroom tyrosinase inhibitor than the peel extract. Peel extract of A. cherimola inhibited mushroom tyrosinase but activated the murine enzyme. F. margarita pulp and peel extracts showed the highest in vitro SPF. A. cherimola, D. kaki, and F. margarita extracts were not cytotoxic for fibroblasts and keratinocytes up to a concentration of 2% (v/v) and the peel extracts were cytotoxic for A375 melanoma cells. To summarize, peel extracts from all analyzed fruit showed comparable or better cosmetic-related properties than pulp extracts and might be considered multifunctional active ingredients of skin lightening, anti-aging, and protective cosmetics.

Utilization of Quince (Cydonia oblonga) Peel and Exploration of Its Metabolite Profiling and Cardioprotective Potential Against Doxorubicin-Induced Cardiotoxicity in Wistar Rats

Quince (Cydonia oblonga Mill.) is a pomaceous fruit that is typically processed into jams, jellies, and marmalade. The byproduct, i.e., the quince peel emanated from the processing industry, can be upcycled, ensuring zero waste policy and resulting in a sustainable food system. In our study, the quince peel was explored for in vitro phytochemical analysis and in vivo cardioprotective potential. Two diverse extractions (ultrasonication and reflux) and four different solvents (aqueous, ethanolic, hydroethanolic, and methanolic) were used for the extraction of quince peel and assessed for the phytochemical and antioxidant study. Among all the evaluated extracts, hydroethanolic quince extract extracted through the reflux extraction method showed the maximum phenolic (27.23 ± 0.85 mg GAE/g DW) and flavonoid (16.5 ± 1.02 mg RE/g DW) content. The maximum antioxidant potential (DPPH) with an IC50 value of 204.8 ± 2.24 μg/mL was noted for the hydroethanolic extract. This best active extract was then subjected to HPTLC, UPLC-MS, mineral, and FTIR analysis to study the metabolic profiling and inorganic composition and to confirm the presence of bioactives. Additionally, the in vivo study was done in rats using doxorubicin (DOX)-induced cardiotoxicity. The rats were given extracts orally at 160 and 320 mg/kg bw for 30 days. ECG analysis was done at the termination of the experiment. Besides this, the lipid profile, blood serum parameters (CK-MB, LDH, AST), and tissue parameters (MDA, SOD, GSH, CAT) were analyzed. The DOX-treated group unveiled a substantial variance (p < 0.001) in all the parameters in contrast to the normal control group and extract control groups. However, the pretreated groups substantially alleviated the DOX-induced changes in all the parameters. Additionally, recuperation in histopathological alterations of the cardiac tissue in contrast to the DOX-induced toxicity was also seen in the pretreated groups. Thus, it could be said that the cardioprotective activity of the quince peel extract attributed to the presence of phytoconstituents counteracted the DOX-induced cardiotoxicity and assisted in the restoration of the cardiac injury in rats.

Cydonia oblonga Mill. Pulp Callus Inhibits Oxidative Stress and Inflammation in Injured Cells

The pharmacological activity of a callus extract from the pulp of Cydonia oblonga Mill., also known as quince, was investigated in murine macrophage (RAW 264.7) and human keratinocyte (HaCaT) cell lines. In particular, the anti-inflammatory activity of C. oblonga Mill. pulp callus extract was assessed in lipopolysaccharides (LPS)-treated RAW 264.7 by the Griess test and in LPS-treated HaCaT human keratinocytes by examining the expression of genes involved in the inflammatory process, including nitric oxide synthase (iNOS), interleukin-6 (IL-6), interleukin-1β (IL-1β), nuclear factor-kappa-B inhibitor alfa (ikBα), and intercellular adhesion molecule (ICAM). The antioxidant activity was evaluated by quantizing the reactive oxygen species (ROS) production in the hydrogen peroxide and tert-butyl hydroperoxide-injured HaCaT cell line. The obtained results indicate that C. oblonga callus from fruit pulp extract has anti-inflammatory and antioxidant activities, suggesting its possible application in delaying and preventing acute or chronic diseases associated with aging or in the treatment of wound dressing.

Glutamate, Humic Acids and Their Combination Modulate the Phenolic Profile, Antioxidant Traits, and Enzyme-Inhibition Properties in Lettuce

Lettuce (Lactuca sativa L., Asteraceae) is a popular vegetable leafy crop playing a relevant role in human nutrition. Nowadays, novel strategies are required to sustainably support plant growth and elicit the biosynthesis of bioactive molecules with functional roles in crops including lettuce. In this work, the polyphenolic profile of lettuce treated with glutamic acid (GA), humic acid (HA), and their combination (GA + HA) was investigated using an untargeted metabolomics phenolic profiling approach based on high-resolution mass spectrometry. Both aerial and root organ parts were considered, and a broad and diverse phenolic profile could be highlighted. The phenolic profile included flavonoids (anthocyanins, flavones, flavanols, and flavonols), phenolic acids (both hydroxycinnamics and hydroxybenzoics), low molecular weight phenolics (tyrosol equivalents), lignans and stilbenes. Overall, GA and HA treatments significantly modulated the biosynthesis of flavanols, lignans, low molecular weight phenolics, phenolic acids, and stilbene. Thereafter, antioxidant capacity was evaluated in vitro with 2,2-diphenyln-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) assays. In addition, this study examined the inhibitory properties of enzymes, including acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), tyrosinase, alpha-amylase, and alpha-glucosidase. Compared to individual treatments, the combination of GA + HA showed stronger antioxidant abilities in free radical scavenging and reducing power assays in root samples. Moreover, this combination positively influenced the inhibitory effects of root samples on AChE and BChE and the tyrosinase inhibitory effect of leaf samples. Concerning Pearson's correlations, antioxidant and enzyme inhibition activities were related to phenolic compounds, and lignans in particular correlated with radical scavenging activities. Overall, the tested elicitors could offer promising insights for enhancing the functional properties of lettuce in agricultural treatments.

Component Characterization, In Vitro Activities and Molecular Mechanism of Cydonia oblonga Mill. against Diabetic

Cydonia Oblonga Mill. is widely distributed in Turkey, Uzbekistan and China and commonly used by the food industry to produce jam, jelly and candies. The aim of this study was to investigate the in vitro antidiabetic activity and anti-diabetic mechanism of Cydonia Oblonga Mill. fruit (COMF). The chemical compositions were further characterized in COMF by UPLC-Q-Orbitrap/MS and 65 components including 22 flavonoids, 16 organic acids, 11 polyphenols, 5 amino acids, 3 pentacyclic triterpenoids and 8 other compounds were identified. The antioxidant activity by DPPH scavenging method and α-glucosidase inhibitory activity were tested. Furthermore, we detected the effects of COMF extract on the proliferation activity of HUVECs, cell viability of HUVECs under H₂O₂-induced oxidative stress, and NO production. Then, molecular docking activity and α-glucosidase inhibitory activity of seven key flavonoid components selected by bioinformatics analysis and literature in the COMF were studied. Among them, quercetin showed potent inhibitory activity, kaempferol, isorhamnetin, luteolin and apigenin demonstrated moderate inhibitory activity, while rutin and epicatechin exhibited poor inhibitory activity. Subsequently, the effects of quercetin, kaempferol, isorhamnetin, leteolin and apigenin on the gene expression levels of AKT1, IL-6 and VEGFA were verified by real-time fluorescence quantification (RT-qPCR). Molecular biology result showed that different active ingredients can significantly recover the levels of AKT1, IL-6 and VEGFA in HUVECs injured by high glucose.

Therapeutic and palliative role of a Unani herbal decoction in COVID-19 and similar respiratory viral illnesses: Phytochemical & pharmacological perspective

ETHNOPHARMACOLOGICAL RELEVANCE

Outbreaks of respiratory viral infections like Severe Acute Respiratory Syndrome, Middle-East Respiratory Syndrome, and Coronavirus Disease-2019 have been a regular occurrence in the past 100 years. A significant proportion of the morbidity and mortality in influenza is attributed to the co-morbidities and complications induced by the disease, involving the vital organs and physiological functions. In this context, traditional medicines offer effective protective, palliative, and therapeutic benefits, as observed in several studies on various types of influenza, including COVID-19. The Unani herbal decoction comprising of 'Unnāb (Ziziphus jujuba Mill. fruit), Sapistān (Cordia dichotoma G. Forst. fruit), and Behīdāna (Cydonia oblonga Mill. seed) was originally prescribed by Hakim Ajmal Khan (1868-1927 AD) for various respiratory ailments as a bronchodilator, anti-inflammatory, and for clearing the respiratory tract. During COVID-19, the decoction was prescribed by the Ministry of Ayurveda, Yoga, Unani, Siddha, and Homeopathy (AYUSH), Government of India, for mild patients in home isolation, and also as a self-care drink for healthy people. Preliminary studies are of the view that the decoction could reduce COVID-19 incidence and prevent severe disease in the population where it was administered.

AIMS OF THE STUDY

We intend to review the pharmacological activity of the Unani decoction ingredients, i.e., Z. jujuba, C. dichotoma, and C. oblonga, in context with respiratory viral infections and their co-morbidities, to develop an understanding of its action mechanism.

METHODOLOGY

We reviewed Unani classical textbooks for information on the therapeutic activity of the decoction ingredients. Scientific studies published in English from the year 2000 onwards on leading scientific websites (PubMed, MEDLINE, Scopus, and Springer) were searched for information regarding the efficacy of the drugs in influenza and its common complications. Non-English language articles, or those published prior to 2000, and those which included plant parts other than those traditionally included in the decoction were excluded.

OBSERVATIONS

A wide range of therapeutic and palliative effects have been observed in the three herbs included in the Unani decoction, including anti-viral, anti-bacterial, immuno-modulatory, anti-inflammatory, hepato-, and nephroprotective, anti-atherosclerotic, anti-tussive, broncho-dilatory, and regulation of gut microbiota. Together, these effects can help to mitigate and prevent most of the complications caused as a result of respiratory viral infections.

CONCLUSION

The combined effects of ingredients in this Unani herbal decoction can potentially help to mitigate most of the pathological changes and complications caused by influenza viruses. With further clinical research, the decoction may be potentially utilized as a prophylactic and therapeutic against viral influenza.

Anthocyanins, Carotenoids and Chlorophylls in Edible Plant Leaves Unveiled by Tandem Mass Spectrometry

Natural pigments are a quite relevant group of molecules that are widely distributed in nature, possessing a significant role in our daily lives. Besides their colors, natural pigments are currently recognized as having relevant biological properties associated with health benefits, such as anti-tumor, anti-atherogenicity, anti-aging and anti-inflammatory activities, among others. Some of these compounds are easily associated with specific fruits (such as blueberries with anthocyanins, red pitaya with betalain or tomato with lycopene), vegetables (carrots with carotenoids), plant leaves (chlorophylls in green leaves or carotenoids in yellow and red autumn leaves) and even the muscle tissue of vertebrates (such as myoglobin). Despite being less popular as natural pigment sources, edible plant leaves possess a high variety of chlorophylls, as well as a high variety of carotenoids and anthocyanins. The purpose of this review is to critically analyze the whole workflow employed to identify and quantify the most common natural pigments (anthocyanin, carotenoids and chlorophylls) in edible plant leaves using tandem mass spectrometry. Across the literature there, is a lack of consistency in the methods used to extract and analyze these compounds, and this review aims to surpass this issue. Additionally, mass spectrometry has stood out in the context of metabolomics, currently being a widely employed technique in this field. For the three pigments classes, the following steps will be scrutinized: (i) sample pre-preparation, including the solvents and extraction conditions; (ii) details of the chromatographic separation and mass spectrometry experiments (iii) pigment identification and quantification.

Phenolic Acids and Flavonoids in Acetonic Extract from Quince (Cydonia oblonga Mill.): Nutraceuticals with Antioxidant and Anti-Inflammatory Potential

Quince (Cydonia oblonga Mill.) is a potential source of polyphenolic compounds related with beneficial biological processes. In this study polyphenols from quince fruit were extracted with aqueous acetone at different ratios. A polyphenol profile was identified and quantified by LC-ESI-QqQ. The antioxidant capacity (ORAC and DPPH) and anti-inflammatory effect (inhibition of COX-2 cyclooxygenase) were evaluated in vitro. The results indicated an effect of the aqueous acetone ratio on the extraction of polyphenolic compounds. The higher extraction yields of polyphenolic compounds were attained with 60-75% aqueous acetone. However, extracts obtained with 85% aqueous acetone promoted higher antioxidant and anti-inflammatory effects. Optimal scaling analysis indicated that hydroxycinnamic acids (quinic and chlorogenic), hydroxybenzoic acids (vanillic and syringic), flavonoids (quercetin and kaempferol), dihydrochalcones (neohesperidin) and flavones (acacetin) are related to the antioxidant activity of quince. While phenolic acids, flavonols (kaempferol-3-O-glucoside and rutin) and flavanols (epicatechin) generated the anti-inflammatory effect by inhibiting 52.3% of the COX-2 enzyme. Therefore, a selective extraction of phenolic mix can reduce oxidative stress or inflammatory processes. This suggests the use of quince as a natural source with significant nutraceutical potential.

The Untargeted Phytochemical Profile of Three Meliaceae Species Related to In Vitro Cytotoxicity and Anti-Virulence Activity against MRSA Isolates

BACKGROUND

A high mortality rate is associated with about 80% of all infections worldwide, mainly due to antimicrobial resistance. Various antimicrobial and cytotoxic activities have been proposed for Meliaceae species. This study aimed to evaluate the in vitro anti-virulence and cytotoxic effect of the leaf extracts of Aphanamixis polystachya, Toona ciliata and Melia azedarach against five MRSA strains and on three cancer cell lines, followed by biological correlation to their encompassed phytoconstituents.

MATERIAL AND METHODS

We explored three plants of this family against a panel of Methicillin-resistant Staphylococcus aureus (MRSA) strains and several cancer cell lines to select the most promising candidates for further in vivo and preclinical studies. The phytochemical composition was evaluated by UHPLC-QTOF-MS untargeted profiling. Cell viability was assessed by SRB assay. Minimum Inhibitory Concentration was carried out by using the agar micro-dilution technique. Inhibition of biofilm formation and preformed biofilm disruption were assessed spectrophotomertically, according to the Sultan and Nabil method (2019).

RESULTS

A total of 279 compounds were putatively annotated to include different phytochemical classes, such as flavonoids (108), limonoids/terpenoids (59), phenolic acids (49) and lower-molecular-weight phenolics (39). A. polystachya extract showed the most potent cytotoxic activity against Huh-7, DU-145 and MCF-7 cell lines (IC₅₀ = 3, 3.5 and 13.4 µg mL^-1, respectively), followed by M. azedarach, with no effect recorded for T. ciliata extract. Furthermore, both A. polystachya and M. azedarach extracts showed promising anti-virulence and antimicrobial activities, with A. polystachya being particularly active against MRSA. These two latter extracts could inhibit and disrupt the biofilm, formed by MRSA, at sub-lethal concentrations. Interestingly, the extracts inhibited hemolysin-α enzyme, thus protecting rabbit RBCs from lysis. A. polystachya extract reduced the pigmentation and catalase enzyme activity of tested pigmented strains better than M. azedarach at both tested sub-MICs. Consequently, susceptibility of the extract-treated cells to oxidant killing by 200 mM H₂O₂ increased, leading to faster killing of the cells within 120 min as compared to the extract-non-treated cells, likely due to the lower antioxidant-scavenging activity of cells exhibiting less staphyloxanthin production.

CONCLUSION

These findings suggested that both A. polystachya and M. azedarach natural extracts are rich in bioactive compounds, mainly limonoids, phenolics and oxygenated triterpenoids, which can combat MRSA biofilm infections and could be considered as promising sources of therapeutic cytotoxic, antibiofilm and anti-virulence agents.