Screening and identification of potential hypoglycemic and hypolipidemic compounds from aqueous extract of Scutellaria baicalensis Georgi root combing affinity ultrafiltration with multiple drug targets and in silico analysis.

INTRODUCTION: Scutellaria baicalensis Georgi, a traditional Chinese medicine, is widely applied to treat various diseases among people, especially in East Asia. However, the specific active compounds in S. baicalensis aqueous extracts (SBAEs) responsible for the hypoglycemic and hypolipidemic properties as well as their potential mechanisms of action remain unclear. OBJECTIVES: This work aimed to explore the potential hypoglycemic and hypolipidemic compounds from SBAE and their potential mechanisms of action. METHODOLOGY: The in vitro inhibitory tests against lipase and α-glucosidase, and the effects of SBAE on glucose consumption and total triglyceride content in HepG2 cells were first performed to evaluate the hypoglycemic and hypolipidemic effects. Then, affinity ultrafiltration liquid chromatography-mass spectrometry (LC-MS) screening strategy with five drug targets, including α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP1B), lipase and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) was developed to screen out the potential active constituents from SBAE, and some representative active compounds were further validated. RESULTS: SBAE displayed noteworthy hypoglycemic and hypolipidemic properties, and 4, 10, 4, 8, and 8 potential bioactive components against α-amylase, α-glucosidase, PTP1B, HMGCR, and lipase were initially screened out, respectively. The interaction network was thus constructed between the potential bioactive compounds screened out and their corresponding drug targets. Among them, baicalein, wogonin, and wogonoside were revealed to possess remarkable hypoglycemic and hypolipidemic effects. CONCLUSION: The potential hypolipidemic and hypoglycemic bioactive compounds in SBAE and their mode of action were initially explored through ligand-target interactions by combining affinity ultrafiltration LC-MS strategy with five drug targets.

Potential antioxidative and anti-hyperuricemic components in Rodgersia podophylla A. Gray revealed by bio-affinity ultrafiltration with SOD and XOD.

Rodgersia podophylla A. Gray (R. podophylla) is a traditional Chinese medicine with various pharmacological effects. However, its antioxidant and anti-hyperuricemia components and mechanisms of action have not been explored yet. In this study, we first assessed the antioxidant potential of R. podophylla with 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferric ion reducing antioxidant power (FRAP) assays. The results suggested that the ethyl acetate (EA) fraction of R. podophylla not only exhibited the strongest DPPH, ABTS radical scavenging and ferric-reducing activities, but also possessed the highest total phenolic and total flavonoid contents among the five fractions. After that, the potential superoxide dismutase (SOD) and xanthine oxidase (XOD) ligands from the EA fraction were quickly screened and identified through the bio-affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC-MS). Accordingly, norbergenin, catechin, procyanidin B2, 4-O-galloylbergenin, 11-O-galloylbergenin, and gallic acid were considered to be potential SOD ligands, while gallic acid, 11-O-galloylbergenin, catechin, bergenin, and procyanidin B2 were recognized as potential XOD ligands, respectively. Moreover, these six ligands effectively interacted with SOD in molecular docking simulation, with binding energies (BEs) ranging from -6.85 to -4.67 kcal/mol, and the inhibition constants (Ki) from 9.51 to 379.44 µM, which were better than the positive controls. Particularly, catechin exhibited a robust binding affinity towards XOD, with a BE value of -8.54 kcal/mol and Ki value of 0.55 µM, which surpassed the positive controls. In conclusion, our study revealed that R. podophylla possessed remarkable antioxidant and anti-hyperuricemia activities and that the UF-LC-MS method is suitable for screening potential ligands for SOD and XOD from medicinal plants.

Exploring multifunctional components from Andrographis paniculata by affinity ultrafiltration with three molecular targets.

Andrographis paniculata (Burm. F.) Nees (AP) was a typical plant resource that has the concomitant function of both foodstuff and medicine, while the action mechanisms of its immune regulation, anti-inflammatory and anti-viral effects and the specific components remain unclear. In this work, a screening approach combining bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF-LC/MS) was hired to screen potential bioactive compounds from AP. The crude extract of AP exerted COX-2 and ACE2 inhibitory effects by other bioassays. Meanwhile, a total of eleven ligands targeting COX-2, IL-6 and ACE2 were screened out. Thereinto, two compounds including andrographolide and 14-deoxy-11,12-didehydroandrographolide exhibited strong binding affinities to COX-2, IL-6 and ACE2 by UF-LC/MS and molecular docking analysis. This is the first report to apply UF-LC/MS approach to rapidly screen out multi-target ligands from AP, and further decipher corresponding mechanisms, which could be beneficial to expedite the search for new multi-target bioactive compounds in other natural products or foods.

What Approaches to Thwart Bacterial Efflux Pumps-Mediated Resistance?

An effective response that combines prevention and treatment is still the most anticipated solution to the increasing incidence of antimicrobial resistance (AMR). As the phenomenon continues to evolve, AMR is driving an escalation of hard-to-treat infections and mortality rates. Over the years, bacteria have devised a variety of survival tactics to outwit the antibiotic's effects, yet given their great adaptability, unexpected mechanisms are still to be discovered. Over-expression of efflux pumps (EPs) constitutes the leading strategy of bacterial resistance, and it is also a primary driver in the establishment of multidrug resistance (MDR). Extensive efforts are being made to develop antibiotic resistance breakers (ARBs) with the ultimate goal of re-sensitizing bacteria to medications to which they have become unresponsive. EP inhibitors (EPIs) appear to be the principal group of ARBs used to impair the efflux system machinery. Due to the high toxicity of synthetic EPIs, there is a growing interest in natural, safe, and innocuous ones, whereby plant extracts emerge to be excellent candidates. Besides EPIs, further alternatives are being explored including the development of nanoparticle carriers, biologics, and phage therapy, among others. What roles do EPs play in the occurrence of MDR? What weapons do we have to thwart EP-mediated resistance? What are the obstacles to their development? These are some of the core questions addressed in the present review.

Potential Antioxidative and Anti-Hyperuricemic Components Targeting Superoxide Dismutase and Xanthine Oxidase Explored from Polygonatum Sibiricum Red.

Polygonatum sibiricum Red. (P. sibiricum) has been used as a traditional Chinese medicine with a wide range of pharmacology effects. However, the responsible bioactive compounds and their mechanisms of action concerning its antioxidative and anti-hyperuricemic activities remain unexplored. In this work, the antioxidant capacity of P. sibiricum was firstly evaluated with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3ethylbenzthiazoline)-6-sulfonic acid (ABTS) and ferric-reducing antioxidant power (FRAP) assays, from which the ethyl acetate (EA) fraction exhibited the highest DPPH, ABTS radical scavenging, and ferric-reducing capacities. Meanwhile, the EA fraction displayed the highest total phenolic and flavonoid contents among the four fractions. Next, the potential ligands from the EA fraction were screened out by bio-affinity ultrafiltration liquid chromatography-mass spectrometry (UF-LC-MS) with superoxide dismutase (SOD) and xanthine oxidase (XOD). As a result, N-trans-p-coumaroyloctopamine, N-trans-feruloyloctopamine, N-trans-feruloyltyramine were identified as potential SOD ligands, while N-cis-p-coumaroyltyramine was determined as potential XOD ligand. Additionally, these four ligands effectively interact with SOD and XOD in the molecular docking analysis, with binding energies (BEs) ranging from -6.83 to -6.51 kcal/mol, and the inhibition constants (Ki) from 9.83 to 16.83 µM, which were better than the positive controls. In conclusion, our results indicated that P. sibiricum has good antioxidative and anti-hyperuricemic activities, and its corresponding active ligands targeting SOD and XOD could be explored by the UF-LC-MS method.

Potential Multifunctional Bioactive Compounds from Dysosma versipellis Explored by Bioaffinity Ultrafiltration-HPLC/MS with Topo I, Topo II, COX-2 and ACE2.

Background: Dysosma versipellis (D. versipellis) has been traditionally used as a folk medicine for ages. However, the specific phytochemicals responsible for their correlated anti-inflammatory, anti-proliferative and antiviral activities remain unknown. Purpose: This study aimed to explore the specific active components in D. versipellis responsible for its potential anti-inflammatory, anti-proliferative, and antiviral effects, and further elucidate the corresponding mechanisms of action. Methods: Bioaffinity ultrafiltration coupled to liquid chromatography-mass spectrometry (UF-LC/MS) was firstly hired to fast screen for the anti-inflammatory, anti-proliferative and antiviral compounds from rhizomes of D. versipellis, and then further validation was conducted using in vitro inhibition assays and molecular docking. Results: A total of 12, 12, 9 and 12 phytochemicals with considerable affinities to Topo I, Topo II, COX-2 and ACE2 were fished out, respectively. The anti-proliferative assay in vitro indicated that podophyllotoxin and quercetin exhibited comparably strong inhibitory rates on A549 and HT-29 cells compared with 5-FU and etoposide. Meanwhile, kaempferol displayed prominent dose-dependent inhibition against COX-2 with IC50 value at 0.36 ± 0.02 µM lower than indomethacin at 0.73 ± 0.07 µM. Furthermore, quercetin exerted stronger inhibitory effect against ACE2 with IC50 value at 104.79 ± 8.26 µM comparable to quercetin 3-O-glucoside at 135.25 ± 6.54 µM. Conclusion: We firstly showcased an experimental investigation on the correlations between bioactive phytochemicals of D. versipellis and their multiple drug targets reflecting its potential pharmacological activities, and further constructed a multi-target and multi-component network to decipher its empirical traditional applications. It could not only offer a reliable and valuable experimental basis to better comprehend the curative effects of D. versipellis but also provide more new insights and strategies for other traditional medicinal plants.

Screening and characterisation of potential antioxidant, hypoglycemic and hypolipidemic components revealed in Portulaca oleracea via multi-target affinity ultrafiltration LC-MS and molecular docking.

INTRODUCTION: Portulaca oleracea is a commonly used nutritional vegetable and traditional herbal medicine with plenty of nutrients and manifold pharmacological activities. However, the potential active ingredients for its remarkable antioxidant, hypoglycemic and hypolipidemic activities remain unexplored. OBJECTIVES: The present study aims to systematically evaluate the antioxidant activities of different extracts of P. oleracea and screen bioactive ligands that can interact with α-glucosidase, pancreatic lipase, and superoxide dismutase (SOD). METHODS: In this research, the antioxidant activities of different parts of P. oleracea and their corresponding total phenolic content (TPC) and total flavonoid content (TFC) were systematically determined. Subsequently, a multi-target affinity ultrafiltration method was developed using affinity ultrafiltration with SOD, α-glucosidase, and pancreatic lipase coupled to liquid chromatography-mass spectrometry (UF-LC-MS). Later, molecular docking was used to further investigate the possible interaction mechanism between these ligands and target enzymes. RESULTS: Among them, the ethyl acetate (EA) fraction showed the highest antioxidant activity along with the highest TPC and TFC, and four compounds in the EA fraction were quickly retrieved as potential SOD, α-glucosidase, and pancreatic lipase ligands, respectively. Molecular docking revealed that these potential ligands exhibited strong binding ability and inhibitory activities on SOD, α-glucosidase, and pancreatic lipase. CONCLUSION: The present study revealed that P. oleracea can be used as a functional food with excellent antioxidant, hypoglycemic and hypolipidemic effects. Meanwhile, the integrated strategy based on multi-target UF-LC-MS and molecular docking also provided a powerful tool and a multidimensional perspective for further exploration of active ingredients in P. oleracea responsible for the antioxidant, hypoglycemic and hypolipidemic activities.

Potential hypoglycemic, hypolipidemic, and anti-inflammatory bioactive components in Nelumbo nucifera leaves explored by bioaffinity ultrafiltration with multiple targets.

Leaf of Nelumbo nucifera Gaertn. (N. nucifera) has been widely used as the main ingredient in lipid-lowering herbal teas and some prescriptions in China due to their excellent hypoglycemic and hypolipidemic effects. However, the active components responsible for these beneficial properties and their mechanisms remain unexplored. In this work, the N. nucifera leaf extracts significantly promoted the glucose consumption of HepG2 cells, and also exhibited remarkable inhibitory activities against α-glucosidase, pancreatic lipase, and COX-2. Furthermore, the top four potential active compounds (N-nornuciferine, Nuciferine, 2-Hydroxy-1-methoxyaporphine, and Isorhamnetin 3-O-glucoside) targeting the above three enzymes were screened out by bioaffinity ultrafiltration with multiple targets coupled with HPLC-MS/MS. The enzyme inhibitory activities of candidate compounds were verified by enzyme inhibition assay and molecular docking. In addition, molecular docking revealed the binding information between the candidate molecules and enzymes. The current study provided valuable information in discovering functional active ingredients from complex medicinal plant extracts.

Exploring Multifunctional Bioactive Components from Podophyllum sinense Using Multi-Target Ultrafiltration.

Podophyllum sinense (P. sinense) has been used as a traditional herbal medicine for ages due to its extensive pharmaceutical activities, including antiproliferative, anti-inflammatory, antiviral, insecticidal effects, etc. Nevertheless, the specific bioactive constituents responsible for its antiproliferative, anti-inflammatory, and antiviral activities remain elusive, owing to its complicated and diversified chemical components. In order to explore these specific bioactive components and their potential interaction targets, affinity ultrafiltration with multiple drug targets coupled with high performance liquid chromatography/mass spectrometry (UF-HPLC/MS) strategy was developed to rapidly screen out and identify bioactive compounds against four well-known drug targets that are correlated to the application of P. sinense as a traditional medicine, namely, Topo I, Topo II, COX-2, and ACE2. As a result, 7, 10, 6, and 7 phytochemicals were screened out as the potential Topo I, Topo II, COX-2, and ACE2 ligands, respectively. Further confirmation of these potential bioactive components with antiproliferative and COX-2 inhibitory assays in vitro was also implemented. Herein, diphyllin and podophyllotoxin with higher EF values demonstrated higher inhibitory rates against A549 and HT-29 cells as compared with those of 5-FU and etoposide. The IC50 values of diphyllin were calculated at 6.46 ± 1.79 and 30.73 ± 0.56 µM on A549 and HT-29 cells, respectively. Moreover, diphyllin exhibited good COX-2 inhibitory activity with the IC50 value at 1.29 ± 0.14 µM, whereas indomethacin was 1.22 ± 0.08 µM. In addition, those representative constituents with good affinity on Topo I, Topo II, COX-2, or ACE2, such as diphyllin, podophyllotoxin, and diphyllin O-glucoside, were further validated with molecular docking analysis. Above all, the integrated method of UF-HPLC/MS with multiple drug targets rapidly singled out multi-target bioactive components and partly elucidated their action mechanisms regarding its multiple pharmacological effects from P. sinense, which could provide valuable information about its further development for the new multi-target drug discovery from natural medicines.

Stimulation of ROS Generation by Extract of Warburgia ugandensis Leading to G0/G1 Cell Cycle Arrest and Antiproliferation in A549 Cells.

Warburgia ugandensis Sprague (WU) is a traditional medicinal plant used for the treatment of various diseases, including cancer, in Africa. This study aimed to evaluate the anti-non-small cell lung cancer (NSCLC) activities of WU against A549 cells and to reveal potential molecular mechanisms. The cytotoxicity of various WU extracts was evaluated with HeLa (cervical cancer), HepG2 (liver cancer), HT-29 (colorectal cancer), and A549 (non-small cell lung cancer) cells by means of Sulforhodamine B (SRB) assay. Therein, the dimethyl carbonate extract of WU (WUD) was tested with the most potent anti-proliferative activity against the four cancer cell lines, and its effects on cell viability, cell cycle progression, DNA damage, intracellular reactive oxygen species (ROS), and expression levels of G0/G1-related proteins in A549 cells were further examined. First, it was found that WUD inhibited the proliferation of A549 cells in a time- and dose-dependent manner. In addition, WUD induced G0/G1 phase arrest and modulated the expression of G0/G1 phase-associated proteins Cyclin D1, Cyclin E1, and P27 in A549 cells. Furthermore, WUD increased the protein abundance of P27 by inhibiting FOXO3A/SKP2 axis-mediated protein degradation and also significantly induced the γH2AX expression and intracellular ROS generation of A549 cells. It was also found that the inhibitory effect of WUD on the proliferation and G0/G1 cell cycle progression of A549 cells could be attenuated by NAC, a ROS scavenger. On the other hand, phytochemical analysis of WUD with UPLC-QTOF-MS/MS indicated 10 sesquiterpenoid compounds. In conclusion, WUD exhibited remarkable anti-proliferative effects on A549 cells by improving the intracellular ROS level and by subsequently modulating the cell proliferation and G0/G1 cell cycle progression of A549 cells. These findings proved the good therapeutic potential of WU for the treatment of NSCLC.

Acyl Quinic Acid Derivatives Screened Out from Carissa spinarum by SOD-Affinity Ultrafiltration LC-MS and Their Antioxidative and Hepatoprotective Activities.

Carissa spinarum Linn. has been utilized both in the food industry and as a traditional medicine for various ailments, while the responsible chemical components and action mechanisms of its antioxidative and hepatoprotective activities remain unclear. In this work, at least 17 quinic acid derivatives as potential ligands for the superoxide dismutase (SOD) enzyme from Carissa spinarum L. were screened out using the bio-affinity ultrafiltration with liquid chromatography mass spectrometry (UF-LC/MS), and 12 of them (1-12), including, three new ones (1-3), were further isolated by phytochemical methods and identified by high resolution electrospray ionization mass spectrometry (HR-ESI-MS) and extensive nuclear magnetic resonance (NMR) spectroscopic analysis. All of these isolated compounds were evaluated for their antioxidant activities by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) methods. As a result, compounds 4 and 6-11 displayed similar or better antioxidant activities compared to vitamin C, which is in good agreement with the bio-affinity ultrafiltration with SOD enzyme. Then, these compounds, 4 and 6-11, with better antioxidant activity were further explored to protect the L02 cells from H2O2-induced oxidative injury by reducing the reactive oxygen species (ROS) and Malondialdehyde (MDA) production and activating the SOD enzyme. To the best of our knowledge, this is the first report to use an efficient ultrafiltration approach with SOD for the rapid screening and identification of the SOD ligands directly from a complex crude extract of Carissa spinarum, and to reveal its corresponding active compounds with good antioxidative and hepatoprotective activities.

Insecticidal Activities Against Odontotermes formosanus and Plutella xylostella and Corresponding Constituents of Tung Meal from Vernicia fordii.

The environmental pollution, pesticide resistance, and other associated problems caused by traditional chemical pesticides with limited modes of action make it urgent to seek alternative environmentally-friendly pesticides from natural products. Tung meal, the byproduct of the detoxified Vernicia fordii (Hemsl.) seed, has been commonly used as an agricultural fertilizer and as a pesticide. However, its active insecticidal extracts and ingredients remain elusive. In the present study, the contact toxicities of tung meal extracts against the agricultural and forest pests like O. formosanus and P. xylostella were examined. Our results showed that ethyl acetate and petroleum ether extracts showed the strongest toxicity against O. formosanus and P. xylostella, respectively. In order to further explore the chemical profiles of the ethyl acetate and petroleum ether extracts, UPLC-Q/TOF-MS and GC-MS analyses have been performed, and 20 and 29 compounds were identified from EA and PE extracts, respectively. The present study, for the first time, verified the noteworthy insecticidal activities on the aforementioned agricultural and forest pesticides and revealed the potential active parts and chemical composition, which are conducive to further exploiting the potential of tung meal as a natural plant-derived insecticide for biological control of agricultural and forest pests.

Antioxidant and Antiproliferative Potentials of Ficus glumosa and Its Bioactive Polyphenol Metabolites.

Ficus glumosa Delile (Moraceae), a reputed plant that is used in herbal medicine, is of high medicinal and nutritional value in local communities primarily ascribed to its phytochemical profile. Currently, there are hardly any fine details on the chemical profiling and pharmacological evaluation of this species. In this study, the flavonoids and phenolics contents of the ethanol extracts and four extracted fractions (petroleum ether (PE), ethyl acetate (EA), n-butanol, and water) of the stem bark of Ficus glumosa were firstly quantified. Further, their antioxidant and antiproliferative potentials were also evaluated. The quantitative determination indicated that the EA and n-butanol fractions possessed the highest total flavonoids/phenolics levels of 274.05 ± 0.68 mg RE/g and 78.87 ± 0.97 mg GAE/g, respectively. Similarly, for the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays, the EA fraction exhibited high potency in both DPPH and ABTS+ scavenging activities with IC50 values of 0.23 ± 0.03 mg/mL, 0.22 ± 0.03 mg/mL, and FRAP potential of 2.81 ± 0.01 mg Fe2+/g, respectively. Furthermore, the EA fraction displayed high cytotoxicity against human lung (A549) and colon (HT-29) cancer cells. Additionally, the liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was employed in order to characterize the chemical constituents of the EA fraction of Ficus glumosa stem bark. Our findings revealed 16 compounds from the EA fraction that were possibly responsible for the strong antioxidant and anti-proliferative properties. This study provides edge-cutting background information on the exploitation of Ficus glumosa as a potential natural antioxidant and anti-cancer remedy.

Identification of Anti-Inflammatory and Anti-Proliferative Neolignanamides from Warburgia ugandensis Employing Multi-Target Affinity Ultrafiltration and LC-MS.

Previous reports have illustrated that the incidence and mortality of cancer are increasing year by year worldwide. In addition, the occurrence, development, recurrence and metastasis of cancer are closely related to inflammation, which is a kind of defensive response of human body to various stimuli. As an important medicinal plant in Africa, Warburgia ugandensis has been reported to have certain anti-inflammatory and anti-proliferative activities, but its specific components and mechanisms of action remain elusive. To tackle this challenge, affinity ultrafiltration with drug targets of interest coupled to high-performance liquid chromatography-mass spectrometry (AUF-HPLC-MS/MS) could be utilized to quickly screen out bioactive constituents as ligands against target enzymes from complex extracts of this plant. AUF-HPLC-MS/MS with four drug targets, i.e., cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX), topoisomerase I (Top I) and topoisomerase II (Top II) were used to rapidly screen and characterize the anti-inflammatory and anti-proliferative natural ligands from W. ugandensis, and the resulting potential active compounds as ligands with specific binding affinity to COX-2, 5-LOX, Top I and Top II, were isolated with modern separation and purification techniques and identified with spectroscopic method like NMR, and then their antiinflammatory and anti-proliferative activities were tested to verify the screening results from AUF-HPLC-MS/MS. Compounds 1 and 2, which screened out and identified from W. ugandensis showed remarkable binding affinity to COX-2, 5-LOX, Top I and Top II with AUF-HPLC-MS/MS. In addition, 1 new compound (compound 3), together with 5 known compounds were also isolated and identified from W. ugandensis. The structure of compound 3 was elucidated by extensive 1D, 2D NMR data and UPLC-QTOF-MS/MS. Furthermore, compounds 1 and 2 were further proved to possess both anti-inflammatory and anti-proliferative activities which are in good agreement with the screening results using AUF-HPLC-MS/MS. This work showcased an efficient method for quickly screening out bioactive components with anti-inflammatory and anti-proliferative activity from complex medicinal plant extracts using AUF-HPLC-MS/MS with target enzymes of interest, and also demonstrated that neolignanamides (compounds 1 and 2) from W. ugandensis would be the active components responsible for its anti-inflammatory and anti-proliferative activity with the potential to treat cancer and inflammation.

Vitamin C supplementation is necessary for patients with coronavirus disease: An ultra-high-performance liquid chromatography-tandem mass spectrometry finding.

To administer vitamin C (VC) with precision to patients with the coronavirus disease (COVID-19), we developed an ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method to assess plasma VC concentrations. 31 patients with COVID-19 and 51 healthy volunteers were enrolled. VC stability was evaluated in blood, plasma, and precipitant-containing stabilizers. A proportion of 7.7 % of VC was degraded in blood at room temperature (RT) (approximately 20-25 °C) at 1.5 h post administration with respect to the proportion degraded at 0.5 h, but without statistical difference. VC was stable in plasma for 0.75 h at RT, 2 h at 4 °C, 5 days at -40 °C, and 4 h in precipitant-containing stabilizer (2 % oxalic acid) at RT. The mean plasma concentration of VC in patients with COVID-19 was 2.00 mg/L (0.5-4.90) (n = 8), which was almost 5-fold lower than that in healthy volunteers (9.23 mg/L (3.09. 35.30)) (n = 51). After high-dose VC treatment, the mean VC concentration increased to 13.46 mg/L (3.93. 34.70) (n = 36), higher than that in healthy volunteers, and was within the normal range (6-20 mg/L). In summary, we developed a simple UPLC-MS/MS method to quantify VC in plasma, and determined the duration for which the sample remained stable. VC levels in patients with COVID-19 were considerably low, and supplementation at 100 mg/kg/day is considered highly essential.

Correlations between phytochemical fingerprints of Moringa oleifera leaf extracts and their antioxidant activities revealed by chemometric analysis.

INTRODUCTION: Moringa oleifera Lam. is widely cultivated and applied in tropical and subtropical areas. Numerous studies have been focused on the antioxidant capacity of M. oleifera leaves, but its correlated bioactive phytochemicals remain elusive. OBJECTIVE: In order to search for the corresponding chemical compounds from M. oleifera leaves responsible for their antioxidant activity, the correlations between phytochemical fingerprints of 15 batches of M. oleifera leaves and their antioxidant activities were investigated by using chemometric analysis. MATERIAL AND METHODS: Fifteen batches of M. oleifera leaves were extracted with 90% ethanol solution, and their phytochemical fingerprints and antioxidant activities were estimated by using high-performance liquid chromatography-ultraviolet-electrospray ionisation tandem mass spectrometry (HPLC-UV/ESI-MS/MS), and three detected methods, namely 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) assay and ferric-reducing antioxidant power (FRAP) assay, respectively. Chemometric analysis was then applied to reveal the correlations between their phytochemical fingerprints and corresponding antioxidant capacity. RESULTS: Fifteen M. oleifera leaf extracts exhibited strong antioxidant activities, in which 24 common compounds were identified by LC-MS. Furthermore, the partial least squares (PLS) analysis indicated that compounds 14, 16, 18 and 23 were the main potential effective components in at least two antioxidant tests. They were identified as kaempferol 3-O-rutinoside, quercetin 3-O-(6″-malonyl-glucoside), kaempferol 3-O-glucoside, and quercetin derivative, respectively. CONCLUSION: The correlations between phytochemical fingerprints of M. oleifera leaf extracts and their corresponding antioxidant capacities were revealed by chemometric analysis, which provides an alternative method for screening for potential bioactive compounds with antioxidant capacity from M. oleifera leaves.

Inhibition of Growth of Colon Tumors and Proliferation of HT-29 Cells by Warburgia ugandensis Extract through Mediating G0/G1 Cell Cycle Arrest, Cell Apoptosis, and Intracellular ROS Generation.

Warburgia ugandensis Sprague (W. ugandensis), widely distributed in Africa, is a traditional medicinal plant used for the treatment of various diseases including cancer. We intended to evaluate the anticolorectal cancer (CRC) activities of the crude extract from W. ugandensis (WUD) and reveal the underlying molecular mechanisms of its action. We found that WUD inhibited the proliferation of HT-29 and HCT116 cells in a time- and dose-dependent manner and induced intracellular ROS generation. The inhibitory effect of WUD on the proliferation of HT-29 and HCT116 cells could be attenuated by NAC (a ROS scavenger) in a dose-dependent manner. WUD induced G0/G1 phase arrest, down-regulated the protein expression of Cyclin D1 via ROS accumulation in HT-29 cells. In search of the molecular mechanism involved in WUD-induced Cyclin D1 down-regulation, it was found that WUD can suppress PI3K/Akt/GSK3ß signaling pathway in HT-29 cells. Next, it was found that WUD also activated apoptosis, poly-ADP ribose polymerase 1 (PARP1) cleavage and down-regulated pro-caspase 3 in HT-29 and HCT116 cells. Besides, WUD decreased the growth of colon tumors in vivo in the xenograft mouse model. We demonstrated for the first time that ROS and their modulation in the corresponding intracellular signaling could play a significant role in the potential activity of WUD against CRC cells.

Hypoglycemic and hypolipidemic effects of Moringa oleifera leaves and their functional chemical constituents.

Moringa oleifera Lam. (M. oleifera) leaves have long been consumed as both nutritive vegetable and popular folk medicine for hyperglycemia and hyperlipidemia in Kenya communities. In the current study, in vitro inhibition by M. oleifera leaf extract (MOLE, 90% (v/v) ethanol) of α-glucosidase and pancreatic lipase was demonstrated, followed by determination of the effects of MOLE on both glucose consumption and lipid levels (TC, TG, HDL-C and LDL-C) in 3T3-L1 cells. Potential ligands in MOLE were fast screened using affinity ultrafiltration LC-MS, and 14 and 10 components displayed certain binding affinity to α-glucosidase and pancreatic lipase, respectively. Docking studies revealed the binding energies and hydrogen bonds between potential ligands and enzymes. This study suggests that M. oleifera leaves may be a promising natural source for the prevention and treatment of hyperglycemia and hyperlipidemia as well as a functional food or other product for health care in the near future.

Antioxidant, Anti-inflammatory Activities and Polyphenol Profile of Rhamnus prinoides.

Rhamnus prinoides L'Herit (R. prinoides) has long been widely consumed as folk medicine in Kenya and other Africa countries. Previous studies indicated that polyphenols were abundant in genus Rhamnus and exhibited outstanding antioxidant and anti-inflammatory activities. However, there are very few studies on such pharmacological activities and the polyphenol profile of this plant up to now. In the present study, the antioxidant activities of the crude R. prinoides extracts (CRE) and the semi-purified R. prinoides extracts (SPRE) of polyphenol enriched fractions were evaluated to show the strong radical scavenging effects against 1,1-diphenyl-2- picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) (0.510 ± 0.046 and 0.204 ± 0.005, mg/mL), and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (0.596 ± 0.005 and 0.096 ± 0.004, mg/mL), respectively. Later, the SPRE with higher contents of polyphenols and flavonoids displayed obvious anti-inflammatory activities through reducing the NO production at the dosage of 11.11 - 100 µg/mL, and the COX-2 inhibitory activity with an IC50 value at 20.61 ± 0.13 µg/mL. Meanwhile, the HPLC-UV/ESI-MS/MS analysis of polyphenol profile of R. prinoides revealed that flavonoids and their glycosides were the major ingredients, and potentially responsible for its strong antioxidant and anti-inflammatory activities. For the first time, the present study comprehensively demonstrated the chemical profile of R. prinoides, as well as noteworthy antioxidant and anti-inflammatory activities, which confirmed that R. prinoides is a good natural source of polyphenols and flavonoids, and provided valuable information on this medicinal plant as folk medicine and with good potential for future healthcare practice.

Effects of flaxseed supplementation on functional constipation and quality of life in a Chinese population: A randomized trial.

BACKGROUND AND OBJECTIVES: This prospective, randomized, controlled study aimed to evaluate the effects of flaxseed supplementation on functional constipation and quality of life in adult men and women in China. METHODS AND STUDY DESIGN: 90 subjects with functional constipation diagnosed by the Rome IV criteria were enrolled. Subjects were randomly assigned to receive either 50 g/day flaxseed flour with meals (n=60) or 15 mL/day of a lactulose solution on an empty stomach (n=30) every morning for 4 weeks. Wexner constipation scores, stool consistency according to the Bristol Stool Form Scale, and bowel habits (frequency of bowel movements/week, the time spent on defecation) were the primary outcomes. The change in Patient Assessment of Constipation Quality of Life score was the secondary outcome. RESULTS: After 4 weeks, the bowel habits in both groups were significantly improved. The median Wexner constipation score decreased from 14 to 6.5 in the flaxseed group (p<0.001) and from 15 to 9 in the lactulose group (p<0.001). The median defecation frequency per week increased significantly (2 to 7 for flaxseed and 2 to 6 for lactulose, p<0.001 for both groups). The Patient Assessment of Constipation Quality of Life score decreased significantly (-1.34 and -0.66 for flaxseed and lactulose, respectively; p<0.001 for both groups). CONCLUSIONS: Flaxseed flour is somewhat more effective at increasing defecation frequency than lactulose, improving bowel movements and promoting life quality of subjects with chronic functional constipation in the Chinese population.