ABSTRACT
Six diterpenoids including three ent-kauranes (1-2, 4) and three cleistanthanes (3, 5-6) were isolated from the roots and stems of Phyllanthus acidus (L.) Skeels. Of them, (16S)-ent-16,17,18-tri-hydroxy-19-nor-kaur-4-en-3-one (1), phyllanthone A (2), and 6-hydroxycleistanthol (3) are new compounds, while the ent-kaurane diterpenoids were reported from the titled plant for the first time. Their structures were elucidated on the basis of the extensive spectroscopic analyses. Compounds 2 and 4-6 displayed cytotoxic potential with IC50 values ranging from 1.96 to 29.15 µM. They also showed moderate anti-inflammatory activities (IC50 = 6.30-12.05 µM). Particularly, the new ent-kaurane 2 displayed cytotoxic potential against HL-60 (IC50 = 2.00 µM) and MCF-7 (IC50 = 3.55 µM) cells, and anti-inflammatory activity (IC50 = 6.47 µM).
Subject(s)
Diterpenes, Kaurane/toxicity , Diterpenes/toxicity , Phyllanthus/chemistry , Plant Extracts/toxicity , Alkaloids/chemistry , Alkaloids/isolation & purification , Alkaloids/toxicity , Cell Line, Tumor , Diterpenes/chemistry , Diterpenes, Kaurane/chemistry , Humans , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Extracts/chemical synthesis , Plant Roots/chemistry , Plant Stems/chemistryABSTRACT
Sulfur-containing compounds, such as cyclic compounds with a vinyl sulfane structure, exhibit a wide range of biological activities including anticancer activity. Therefore, the development of efficient strategies to synthesize such compounds is a remarkable achievement. We have developed a unique approach for the rapid and modular preparation of nature-inspired cyclic and acyclic sulfur-containing compounds using thioacrolein, a naturally occurring chemically unstable intermediate. We constructed thiopyranone derivatives through the regioselective sequential double Diels-Alder reaction of thioacrolein produced by allicin, a major component in garlic, and two molecules of silyl enol ether as the diene partner. The cytotoxicity toward cancer stem cells of the thiopyranones was equal to or higher than that of (Z)-ajoene (positive control) derived from garlic, and the thiopyranones had higher chemical stability than (Z)-ajoene.
Subject(s)
Acrolein/pharmacology , Antineoplastic Agents/pharmacology , Garlic/chemistry , Neoplastic Stem Cells/drug effects , Plant Extracts/pharmacology , Sulfur Compounds/pharmacology , Acrolein/chemical synthesis , Acrolein/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Survival/drug effects , Density Functional Theory , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Sulfur Compounds/chemical synthesis , Sulfur Compounds/chemistry , Tumor Cells, CulturedABSTRACT
Four series of cajanonic acid A (CAA) derivatives have been designed and synthesized. The newly prepared compounds have been screened for glucose consumption activity in HepG2 cell lines and PPARγ antagonistic activity in HEK293 cell lines. Compound 26g bearing a tetrahydroisoquinolinone scaffold showed the most potent PPARγ antagonistic and hypoglycemic activities. An oral glucose tolerance test (OGTT) was performed and the results further confirmed that 26g was a potent hypoglycemic agent. In addition, the possible binding modes for compound 26g in the PPARγ protein have been investigated in this study.
Subject(s)
PPAR gamma/antagonists & inhibitors , Plant Extracts/pharmacology , Stilbenes/pharmacology , Cajanus/chemistry , Cell Line , Dose-Response Relationship, Drug , Humans , Molecular Structure , PPAR gamma/metabolism , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Stilbenes/chemical synthesis , Stilbenes/chemistry , Structure-Activity RelationshipABSTRACT
Nanoencapsulation of saffron extract (SE) components into the rapeseed lecithin nanoliposomes were performed by sonication of their aqueous dispersions as a green process. Dynamic light scattering (DLS) results exhibited that empty and SE loaded nanoliposomes (SENL) had average sizes in range of 118-138 nm, negative zeta potentials (-32.0 to -46.8 mV) and polydispersity index (PDI) less than 0.3 during storage for 28 days at 4 °C. Encapsulation efficiency of crocin was approximately 30%. The 70% of crocin released from SENLs within 5 h in PBS solution. Pullulan-based films were fabricated by incorporation of empty and SE loaded nanoliposomes into pullulan solution through casting method. The mechanical resistance and thermal stability of the films reduced by addition of nanoliposomes. FTIR and thermal characterizations indicated that SE was successfully encapsulated in the nanoliposomes and film matrix with high thermal stability. Incorporation of nanoliposomes enhanced the oxygen barrier properties of the films, while it didn't significantly affect the water vapor permeability (WVP) of the films. The obtained edible films or coatings can provide additional benefits due to unique flavor and color of saffron. In addition, the utilization of SE, can provide benefits for health-allegation from SE antioxidant capacity.
Subject(s)
Crocus/chemistry , Glucans/chemistry , Nanostructures/chemistry , Plant Extracts/chemistry , Edible Films , Glucans/chemical synthesis , Humans , Liposomes/chemistry , Liposomes/pharmacology , Oxygen/chemistry , Plant Extracts/chemical synthesis , Water/chemistryABSTRACT
Drug-loaded electrospun fibers have attracted increasing attention as a promising wound dressing material due to their capability of preventing from infections and inflammation and maintaining an appropriate environment for wound healing. In this study, polylactic acid (PLA), which is widely used in wound management, was chosen as electrospinnable polymer. A triterpene extract (TE) from the outer bark of birch known for its anti-inflammatory, antiviral, antibacterial, and wound healing effects was chosen to produce TE-loaded PLA electrospun fibers for wound dressing. A binary solvent system of dichloromethane (DCM) and dimethyl sulfoxide (DMSO) was employed, and the ratio of the solvents was optimized for preparing smooth and uniform fibers. The morphology of TE-loaded PLA electrospun fibers was investigated by scanning electron microscopy (SEM). The entrapment of TE in PLA fibers was confirmed by confocal laser scanning microscopy (CLSM). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were used to analyze the solid state of TE in PLA fibers. The release behavior of TE was assayed by a shaking flask method for a period of 96 h. The results revealed that TE-loaded electrospun PLA microfibers could be reliably prepared and are promising future candidates in wound therapy.
Subject(s)
Bandages , Betula/chemistry , Nanofibers/chemistry , Plant Bark/chemistry , Polyesters/chemical synthesis , Triterpenes/chemical synthesis , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemical synthesis , Chemistry, Pharmaceutical/methods , Nanofibers/analysis , Plant Extracts/analysis , Plant Extracts/chemical synthesis , Polyesters/analysis , Triterpenes/analysisABSTRACT
In this study for the first time, high efficient, eco-friendly and novel Dy2O3/ZnO-Au ternary nanocomposites (Dy/ZnO-AuNCs) were prepared in presence of pomegranate fruit (PF) extract as capping and reducing agents (Dy/ZnO-AuNCs@PF). The influence of various parameters such as basic agents, reducing agents, sonication power, and sonication time were performed to reach the optimum condition. The formation of the products was characterized by FT-IR, HRTEM, XRD, FE-SEM, TEM, EDX and DRS techniques. The XRD and TEM analysis showed that the morphology and crystallite size of nanocomposites were spherical morphology and 85-90 nm, respectively. The obtained Dy/ZnO-AuNCs@PF were investigated as a nanocatalyst for degradation of erythrosine (ES) as anionic dye and basic violet 10 (BV10) as cationic dye under UV and visible light irradiations. The Dy/ZnO-AuNCs@PF exhibited higher photodegradation against ES (89.6%) and BV10 (91.3%) than pure Dy2O3 (63.1% for ES, 66.5% for BV10) and Dy2O3/ZnO (64.5% for ES, 70.8% for BV10) under UV irradiation. It was found that gold nanoparticles have significant effect on Dy/ZnO-AuNCs@PF catalytic performance for decomposition of organic pollutants. In addition, Dy/ZnO-AuNCs@PF showed excellent in-vitro antibacterial activity against A. baumannii, S. aureus and P. mirabilis with MIC and MBC values of (5, 80 mg/ml), (5, 40 mg/ml) and (2.5, 20 mg/ml), respectively. Generally, according to its excellent antibacterial and catalytic activity, Dy/ZnO-AuNCs@PF can be used in biomedical and environmental applications.
Subject(s)
Anti-Bacterial Agents/pharmacology , Dysprosium/pharmacology , Gold/pharmacology , Nanocomposites/chemistry , Plant Extracts/pharmacology , Zinc Oxide/pharmacology , Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Catalysis , Dose-Response Relationship, Drug , Dysprosium/chemistry , Fruit/chemistry , Gold/chemistry , Green Chemistry Technology , Microbial Sensitivity Tests , Molecular Structure , Photochemical Processes , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Pomegranate/chemistry , Proteus mirabilis/drug effects , Staphylococcus aureus/drug effects , Structure-Activity Relationship , Zinc Oxide/chemistryABSTRACT
Cisplatin (CP) is a chemotherapy agent used in the treatment of cancer, but it has various side effects, in particular, neurotoxicity. Zinc oxide nanoparticles (ZnO NPs) are a potent antioxidant. However, there is limited knowledge about the protective effects of ZnO NPs against CP-induced hippocampal toxicity. The present study aimed to explore the potential protective effects of ZnO NPs against CP-induced oxidative stress, loss of neurotrophins support, and tissue damage in the hippocampus of the rats. Eighty adult male Wistar rats were dividing into ten groups including: control (Con), sham, ZnO Bulk (ZnB), chemical ZnO NPs (ChZnO NPs), Green ZnO NPs (GrZnO NPs), CP, CP + ZnB, CP + ChZnO NPs, CP + GrZnO NPs and CP + AE. CP was administrated (5 mg/kg/weekly) for four weeks, and animals were treated simultaneously with different forms of ZnO (5 mg/kg/day). At the end of the experiment, the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), malondialdehyde (MDA), changes of reduced glutathione (GSH), oxidized glutathione (GSSG) and GSH/GSSG ratio, histological changes, expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) genes were assessed in the hippocampus. The results revealed that a decrease in BDNF and NGF mRNA expression, GSH concentration and GSH/GSSG ratio, increasing of GSSG and MDA levels, and neuronal loss in the CP-treated rats were reversed following the administration of different forms of ZnO, especially Gr ZnO NPs and ch ZnO NPs. Co-administration of ZnO NPs to CP-treated rats restored the suppressive effects of CP on activities of antioxidant enzymes (SOD, GPX, CAT). The results showed that in most of the evaluated factors, Gr ZnO NPs showed a greater protective effect than other forms of ZnO. The results suggest that ZnO NPs, in particular Green ZnO NPs (GrZnO NPs) had more potential protective effects against CP-induced oxidative stress, inadequate support neurotrophin and tissue damage in rat hippocampus.
Subject(s)
Antioxidants/pharmacology , Cisplatin/toxicity , Hippocampus/metabolism , Nanoparticles/administration & dosage , Nerve Growth Factors/biosynthesis , Zinc Oxide/pharmacology , Aloe , Animals , Antineoplastic Agents/toxicity , Antioxidants/chemical synthesis , Green Chemistry Technology/methods , Hippocampus/drug effects , Male , Nanoparticles/chemistry , Oxidative Stress/drug effects , Oxidative Stress/physiology , Plant Extracts/chemical synthesis , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Rats , Rats, Wistar , Zinc Oxide/chemical synthesisABSTRACT
The rising opioid crisis has become a worldwide societal and public health burden, resulting from the abuse of prescription opioids. Targeting the κ-opioid receptor (KOR) in the periphery has emerged as a powerful approach to develop novel pain medications without central side effects. Inspired by the traditional use of sunflower (Helianthus annuus) preparations for analgesic purposes, we developed novel stabilized KOR ligands (termed as helianorphins) by incorporating different dynorphin A sequence fragments into a cyclic sunflower peptide scaffold. As a result, helianorphin-19 selectively bound to and fully activated the KOR with nanomolar potency. Importantly, helianorphin-19 exhibited strong KOR-specific peripheral analgesic activity in a mouse model of chronic visceral pain, without inducing unwanted central effects on motor coordination/sedation. Our study provides a proof of principle that cyclic peptides from plants may be used as templates to develop potent and stable peptide analgesics applicable via enteric administration by targeting the peripheral KOR for the treatment of chronic abdominal pain.
Subject(s)
Abdominal Pain/drug therapy , Analgesics/pharmacology , Peptides, Cyclic/pharmacology , Plant Extracts/pharmacology , Receptors, Opioid, kappa/antagonists & inhibitors , Analgesics/chemical synthesis , Analgesics/chemistry , Animals , Cells, Cultured , Chronic Disease , Dose-Response Relationship, Drug , Drug Design , HEK293 Cells , Helianthus/chemistry , Humans , Male , Mice , Mice, Inbred C57BL , Molecular Structure , Peptides, Cyclic/chemical synthesis , Peptides, Cyclic/chemistry , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Receptors, Opioid, kappa/metabolism , Seeds/chemistry , Structure-Activity RelationshipABSTRACT
INTRODUCTION: Epidermal growth factor receptor (EGFR) inhibition is an imperative therapeutic approach targeting various types of cancer including colorectal, lung, breast, and pancreatic cancer types. Moreover, cyclooxygenase-2 (COX-2) is frequently overexpressed in different types of cancers and has a role in the promotion of malignancy, apoptosis inhibition, and metastasis of tumor cells. Combination therapy has been emerged to improve the therapeutic benefit against cancer and curb intrinsic and acquired resistance. METHODS: Three semi-synthetic series of compounds (C1-4, P1-4, and G1-4) were prepared and evaluated biologically as potential dual epidermal growth factor receptor (EGFR) and COX-2 inhibitors. The main phenolic constituents of Amaranthus spinosus L. (p-coumaric, caffeic and gallic) acids have been isolated and subsequently subjected to diazo coupling with various amines to get novel three chemical scaffolds with potential anticancer activities. RESULTS: Compounds C4 and G4 showed superior inhibitory activity against EGFR (IC50: 0.9 and 0.5 µM, respectively) and displayed good COX-2 inhibition (IC50: 4.35 and 2.47 µM, respectively). Moreover, the final compounds were further evaluated for their cytotoxic activity against human colon cancer (HT-29), pancreatic cancer (PaCa-2), human malignant melanoma (A375), lung cancer (H-460), and pancreatic ductal cancer (Panc-1) cell lines. Interestingly, compounds C4 and G4 exhibited the highest cytotoxic activity with average IC50 values of 1.5 µM and 2.8 µM against H-460 and Panc-1, respectively. The virtual docking study was conducted to gain proper understandings of the plausible-binding modes of target compounds within EGFR and COX-2 binding sites. DISCUSSION: The NMR of prepared compounds showed characteristic peaks that confirmed the structure of the target compounds. The synthesized benzoxazolyl scaffold containing compounds showed inhibitory activities for both COXs and EGFR which are consistent with the virtual docking study.
Subject(s)
Cyclooxygenase 2 Inhibitors/pharmacology , Drug Design , Phenols/pharmacology , Plant Extracts/pharmacology , Protein Kinase Inhibitors/pharmacology , Amaranthaceae/chemistry , Cyclooxygenase 2/metabolism , Cyclooxygenase 2 Inhibitors/chemical synthesis , Cyclooxygenase 2 Inhibitors/chemistry , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , Humans , Molecular Docking Simulation , Molecular Structure , Phenols/chemical synthesis , Phenols/chemistry , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistryABSTRACT
Caffeic acid ß-phenethyl ester (CAPE), an antioxidative bioactive catechol isolated from propolis, was semisynthesized from chlorogenic acid and related compounds in an extract of raw (unroasted) Robusta coffee (Coffea canephora) beans in 5 steps and a total yield of 31%. Oxidative degradation of the intermediates and target molecule was prevented by alkaline hydrolysis of the chlorogenic acids in the presence of sodium dithionite (Na2S2O4) and deprotection of the catecholic diacetate precursor by Candida antarctica lipase B-mediated transesterification as the final step.
Subject(s)
Antioxidants/chemical synthesis , Caffeic Acids/chemical synthesis , Coffea/chemistry , Phenylethyl Alcohol/analogs & derivatives , Plant Extracts/chemical synthesis , Propolis/chemistry , Esterification , Phenylethyl Alcohol/chemical synthesisABSTRACT
Luo Han Guo fruit extract (Siraitia grosvenorii), mainly composed of mogroside V (50%), could be considered a suitable alternative to free sugars; however, its commercial applications are limited by its unpleasant off-notes. In the present work, a central composite design method was employed to optimize the transglycosylation of a mogroside extract using cyclodextrin glucosyltransferases (CGTases) from three different bacteriological sources (Paenibacillus macerans, Geobacillus sp., and Thermoanaerobacter sp.) considering various experimental parameters such as maltodextrin and mogroside concentration, temperature, time of reaction, enzymatic activity, and pH. Product structures were determined by liquid chromatography coupled to a diode-array detector (LC-DAD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Sensory analysis of glucosylated mogrosides showed an improvement in flavor attributes relevant to licorice flavor and aftereffect. Consequently, an optimum methodology was developed to produce new modified mogrosides more suitable when formulating food products as free sugar substitutes.
Subject(s)
Bacterial Proteins/chemistry , Cucurbitaceae/chemistry , Glucosides/biosynthesis , Glucosyltransferases/chemistry , Plant Extracts/chemistry , Sweetening Agents/chemical synthesis , Biocatalysis , Chromatography, High Pressure Liquid , Fruit/chemistry , Geobacillus/enzymology , Glucosides/chemistry , Paenibacillus/enzymology , Plant Extracts/chemical synthesis , Spectrometry, Mass, Electrospray Ionization , Sweetening Agents/chemistry , Thermoanaerobacter/enzymologyABSTRACT
Nature has the potential to reduce metal salts to their relative nanoparticles. Traditionally, physical and chemical methods were used for the synthesis of nanoparticles but due to the use of toxic chemicals, non-ecofriendly methods and other harmful effects, green chemistry approaches are now employed for synthesizing nanoparticles which are basically the most cost effective, ecofriendly and non-hazardous methods. In this review, we aimed to evaluate and study the details of various mechanisms used for green synthesis of silver nanoparticles from plants, their size, shape and potential applications. A total of 150 articles comprising both research and review articles from 2009 to 2019 were selected and studied in detail to get in-depth knowledge about the synthesis of silver nanoparticles specifically through green chemistry approaches. Silver ions and their salts are well known for their antimicrobial properties and have been used in various medical and non-medical applications since the emergence of human civilization. Miscellaneous attempts have been made to synthesize nanoparticles using plants and such nanoparticles are more efficient and beneficial in terms of their antibacterial, antifungal, antioxidant, anti-biofilm and cytotoxic activities than nanoparticles synthesized through physical and chemical processes. Silver nanoparticles have been studied as an important research area due to their specific and tunable properties and their application in the field of biomedicine such as tissue and tumor imaging and drug delivery. These nanoparticles can be further investigated to find out their antimicrobial potential in cell lines and animal models.
Subject(s)
Green Chemistry Technology/methods , Metal Nanoparticles/chemistry , Plant Extracts/chemical synthesis , Plant Structures/chemistry , Silver/chemistry , Animals , Anti-Bacterial Agents/chemical synthesis , Antioxidants/chemical synthesis , Green Chemistry Technology/trends , Humans , Plant Extracts/isolation & purificationABSTRACT
In the case of Proteus vulgaris infection, the increased occurrence of multidrug-resistance strains has become a critical challenge in the treatment of urinary tract diseases. Therefore, using plant extracts as eco-friendly antibacterial provides an attractive solution to battle bacterial infection. The current study investigates the antibacterial and antihemolytic activity of nine medicinal plant extracts against P. vulgaris. Citrus limon extract at 150 µg/ml exhibited the highest antimicrobial action against P. vulgaris (the inhibition zone diameter; 22.7 mm). Zinc oxide nanoparticles (ZnO NPs) are synthesized using the plant extracts of C. limon, Allium sativum, Sonchus bulbosus, Allium cepa, and Asparagus racemosus. The antibacterial activity of ZnO NPs synthesized using C. limon extract at 150 µg/ml is significantly increased (33.8 mm). ZnO NPs synthesized using A. cepa, A. racemosus, and C. limon plant extracts are effectively protective for human red blood cells. The ZnO NPs synthesized using C. limon extract are characterized using UV-Visible spectroscopy, FTIR, XRD, and TEM. FTIR revealed that the plant extracts may serve as reducing and capping agents of ZnO NPs. XRD spectra confirmed the crystallinity of ZnO NPs. TEM image demonstrated the formation of spherical shapes of ZnO NPs with an average size of 37.05 nm. SEM of P. vulgaris cells treated with ZnO NPs showed cellular morphological damage compared to the untreated cells. ZnO NPs are synthesized by gamma irradiation as a clean and novel method. This study recommended the promising uses of the biosynthesized ZnO NPs using plant extracts as a natural, unique approach, to control the pathogenicity of P. vulgaris.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Nanoparticles/chemistry , Plant Extracts/pharmacology , Proteus vulgaris/drug effects , Zinc Oxide/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Gamma Rays , Microbial Sensitivity Tests , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Plants, Medicinal/chemistry , Zinc Oxide/chemical synthesis , Zinc Oxide/chemistryABSTRACT
BACKGROUND: The use of nanoparticles has markedly increased in biomedical sciences. The silver nanoparticles (AgNPs) have been investigated for their applicability to deliver chemotherapeutic/antibacterial agents to treat cancer or infections disease. However, the existing chemical and physical methods of synthesizing AgNPs are considered inefficient, expensive and toxic. METHODS: Natural products have emerged as viable candidates for nanoparticle production, including the use of Terfezia boudieri (T. boudieri), a member of the edible truffle family. Accordingly, our goal was to synthesize AgNPs using an aqueous extract of T. boudieri (green synthesized AgNPs). Since certain infectious agents are linked to cancer, we investigated their potential as anti-cancer and antibacterial agents. RESULTS: The synthesis of AgNPs was confirmed by the presence of an absorption peak at 450nm by spectroscopy. The physico-chemical properties of green synthesized AgNPs were analyzed by UV-Vis, FT-IR, XRD, SEM, and TEM. In addition, their potential to inhibit cancer cell (proliferation and the growth of infectious bacteria were investigated. CONCLUSION: The size of nanoparticles ranged between 20-30nm. They exerted significant cytotoxicity and bactericidal effects in a concentration and time-dependent manner compared to T. boudieri extract alone. Interestingly, the synthesis of smaller AgNPs was correlated with longer synthesis time and enhanced cytotoxic and bactericidal properties.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Ascomycota/chemistry , Metal Nanoparticles/chemistry , Plant Extracts/pharmacology , Silver/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antineoplastic Agents, Phytogenic/chemical synthesis , Antineoplastic Agents, Phytogenic/chemistry , Antioxidants , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Escherichia coli/drug effects , Green Chemistry Technology , Humans , Microbial Sensitivity Tests , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Pseudomonas aeruginosa/drug effects , Silver/chemistry , Staphylococcus aureus/drug effectsABSTRACT
The powerful insecticidal and multi-drug-resistance-reversing activities displayed by the stemofoline group of alkaloids render them promising lead structures for further development as commercial agents in agriculture and medicine. However, concise, enantioselective total syntheses of stemofoline alkaloids remain a formidable challenge due to their structural complexity. We disclose herein the enantioselective total syntheses of four stemofoline alkaloids, including (+)-stemofoline, (+)-isostemofoline, (+)-stemoburkilline, and (+)-(11S,12R)-dihydrostemofoline, in just 19 steps. Our strategy relies on a biogenetic hypothesis, which postulates that stemoburkilline and dihydrostemofolines are biogenetic precursors of stemofoline and isostemofoline. Other highlights of our approach are the use of Horner-Wadsworth-Emmons reaction to connect the two segments of the molecule, an improved protocol allowing gram-scale access to the tetracyclic cage-type core, and a Cu-catalyzed direct and versatile nucleophilic alkylation reaction on an anti-Bredt iminium ion. The synthetic techniques that we developed could also be extended to the preparation of other Stemona alkaloids.
Subject(s)
Heterocyclic Compounds, 4 or More Rings/chemical synthesis , Insecticides/chemical synthesis , Stemonaceae/chemistry , Alkaloids/chemical synthesis , Alkaloids/chemistry , Heterocyclic Compounds, 4 or More Rings/chemistry , Insecticides/chemistry , Molecular Structure , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , StereoisomerismABSTRACT
The biosynthesis of berberine alkaloids is thought to begin with the demethylation of berberine followed by methylation reactions to generate other type berberine alkaloids. This seemingly expeditious way to access berberine alkaloids has been stagnated for over half a century due to certain vexing synthetic problems, such as low isolated yield, complex operations and toxic reagents. We further investigated this bioinspired semi-synthesis strategy and significantly improved the synthetic efficacy, by providing a practical synthetic process for demethyleneberberine (DMB), columbamine and palmatine. Furthermore, we found that DMB (IC50, 9.06 µM) inhibited the activity of monoamine oxidase B (MAO-B), an enzyme that deaminates dopamine and is particularly involved in the pathology of Parkinson's disease. Besides, columbamine was able to decrease MAO-B activity by approximately 40%. These findings provide perquisites for further in vivo investigation to confirm the therapeutic potentiality of berberine alkaloids, DMB in particular.
Subject(s)
Berberine Alkaloids/chemical synthesis , Berberine/analogs & derivatives , Monoamine Oxidase Inhibitors/chemical synthesis , Monoamine Oxidase/metabolism , Plant Extracts/chemical synthesis , Berberine/chemical synthesis , Berberine/pharmacology , Berberine Alkaloids/pharmacology , Binding Sites/physiology , Dose-Response Relationship, Drug , Humans , Monoamine Oxidase Inhibitors/pharmacology , Plant Extracts/pharmacologyABSTRACT
In recent times, magnesium oxide (MgO) nanoparticles are proven to be an excellent antibacterial agent which inhibits the growth of bacteria by generating reactive oxygen species (ROS). Release of ROS by nanoparticles will damage the cell membrane of bacteria and leads to the leakage of bacterial internal components and cell death. However, chemically synthesized MgO nanoparticles may possess toxic functional groups which may inhibit healthy human cells along with bacterial cells. Thus, the aim of the present study is to synthesize MgO nanoparticles using leaf extracts of Amaranthus tricolor and photo-irradiation of visible light as a catalyst, without addition of any chemicals. Optimization was performed using Box-Behnken design (BBD) to obtain the optimum condition required to synthesize smallest nanoparticles. The parameters such as time of reaction, the concentration of precursor, and light intensity have been identified to affect the size of biosynthesized nanoparticles and was optimized. The experiment performed with optimized conditions such as 0.001 M concentration of magnesium acetate as precursor, 5 cm distance of light (intensity), and 15 min of reaction time (light exposure) has led to the formation of 74.6 nm sized MgO nanoparticles. The antibacterial activities of MgO nanoparticles formed via photo-irradiation and conventional biosynthesis approach were investigated and compared. The lethal dosage of E. coli for photo-irradiated and conventional biosynthesis MgO nanoparticles was 0.6 ml and 0.4 ml, respectively. Likewise, the lethal dosage of S. aureus for both biosynthesis approaches was found to be 0.4 ml. The results revealed that the antibacterial activity of MgO nanoparticles from both biosynthesis approaches was similar. Thus, photo-irradiated MgO nanoparticles were beneficial over heat-mediated conventional method due to the reduced synthesis duration.
Subject(s)
Amaranthus , Anti-Bacterial Agents/chemical synthesis , Magnesium Oxide/chemical synthesis , Nanoparticles/chemistry , Plant Extracts/chemical synthesis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/radiation effects , Escherichia coli/drug effects , Escherichia coli/physiology , Humans , Magnesium Oxide/pharmacology , Magnesium Oxide/radiation effects , Nanoparticles/administration & dosage , Nanoparticles/radiation effects , Plant Extracts/pharmacology , Plant Extracts/radiation effects , Radiation , Spectroscopy, Fourier Transform Infrared/methods , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiologyABSTRACT
Prenylated flavanones are polyphenols that have diverse biological properties. The present paper focuses on a HPLC method validation for the quantification of prenylated flavanones (2S)-5,7-dihydroxy-6-(3-methyl-2-buten-1-yl)-2-phenyl-2,3-dihydro-4H-1Benzopyran-4-one 1 and derivatives (2S)-5,7-bis(acetyloxy)-6-(3-methyl-2-buten-1-yl)-2-phenyl-2,3-dihydro-4H-1-Benzopyran-4-one A; (2S)-5-hydroxy-7-methoxy-6-(3-methyl-2-buten-1-yl)-2-phenyl-2,3-dihydro-4H-1-Benzopyran-4-one B; (8S)-5-hydroxy-2,2-dimethyl-8-phenyl-3,4,7,8-tetrahydro-2H,6H-Benzo[1,2-b:5,4-b']dipyran-6-one C; and (8S)-5-hydroxy-2,2-dimethyl-8-phenyl-7,8-dihydro-2H,6H-Benzo[1,2-b:5,4-b']dipyran-6-one D applied in biopharmaceutic studies. The linear relationships are proven with significant correlation coefficients (R2 Ë 0.999) in the range of 1.56 to 200 µg/mL with low limits of detection and quantification, on average of 0.4 µg/mL and 1.2 µg/mL, respectively. The validation method used in this work is highly accurate and precise, with values lower than 15%. The relative standard deviation values of repeatability of the instrumental system are demonstrated with less than 0.6% for all studied flavanones. Therefore, the applicability method of the quantification of the prenylated flavanones was established using the permeation of human skin in the Franz cell system. During the method previously described, there was no interference observed from human skin components in ex vivo permeation studies.
Subject(s)
Fabaceae/chemistry , Flavanones/analysis , Plant Extracts/analysis , Skin/chemistry , Chromatography, High Pressure Liquid , Flavanones/chemical synthesis , Humans , Molecular Structure , Plant Extracts/chemical synthesis , Plant Leaves/chemistry , Skin AbsorptionABSTRACT
Due to their versatile applications, gold (Au) and silver (Ag) nanoparticles (NPs) have been synthesized by many approaches, including green processes using plant extracts for reducing metal ions. In this work, we propose to use plant extract with active biomedical components for NPs synthesis, aiming to obtain NPs inheriting the biomedical functions of the plants. By using leaves extract of Clerodendrum inerme (C. inerme) as both a reducing agent and a capping agent, we have synthesized gold (CI-Au) and silver (CI-Ag) NPs covered with biomedically active functional groups from C. inerme. The synthesized NPs were evaluated for different biological activities such as antibacterial and antimycotic against different pathogenic microbes (B. subtilis, S. aureus, Klebsiella, and E. coli) and (A. niger, T. harzianum, and A. flavus), respectively, using agar well diffusion assays. The antimicrobial propensity of NPs further assessed by reactive oxygen species (ROS) glutathione (GSH) and FTIR analysis. Biofilm inhibition activity was also carried out using colorimetric assays. The antioxidant and cytotoxic potential of CI-Au and CI-Ag NPs was determined using DPPH free radical scavenging and MTT assay, respectively. The CI-Au and CI-Ag NPs were demonstrated to have much better antioxidant in terms of %DPPH scavenging (75.85% ± 0.67% and 78.87% ± 0.19%), respectively. They exhibited excellent antibacterial, antimycotic, biofilm inhibition and cytotoxic performance against pathogenic microbes and MCF-7 cells compared to commercial Au and Ag NPs functionalized with dodecanethiol and PVP, respectively. The biocompatibility test further corroborated that CI-Ag and CI-Au NPs are more biocompatible at the concentration level of 1-50 µM. Hence, this work opens a new environmentally-friendly path for synthesizing nanomaterials inherited with enhanced and/or additional biomedical functionalities inherited from their herbal sources.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Clerodendrum/chemistry , Plant Extracts/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry , Antioxidants/chemical synthesis , Antioxidants/chemistry , Bacteria/drug effects , Biofilms/drug effects , Biphenyl Compounds/antagonists & inhibitors , Dose-Response Relationship, Drug , Fungi/drug effects , Gold/chemistry , Gold/pharmacology , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Picrates/antagonists & inhibitors , Plant Extracts/chemical synthesis , Plant Extracts/chemistry , Silver/chemistry , Silver/pharmacologyABSTRACT
Chromatographic purification of Elephantopus scaber led to 16 new germacrane-type sesquiterpene lactones (1-16), named elephantopinolide A-P, along with a known analogue (17). Their structures were confirmed by comprehensive spectroscopic analyses, single-crystal X-ray diffraction, and comparison between the experimental and calculated ECD spectra. Their hepatocellular inhibition activities against Hep3B and HepG2 cells were screened by MTT assay, and the structure-activity relationships were examined. The results revealed that 10 (IC50 value of 2.83 µM and 1.98 µM) is more potent than sorafenib. The underlying mechanism study demonstrated that 10 could markedly induce apoptosis accompanied by increased ROS production and decreased mitochondrial membrane potential, resulting in the autophagy and G2/M phase cell arrest in Hep3B and HepG2 cells. Furthermore, signal pathways including MAPKs and AKT may play important roles in 10-induced hepatocellular carcinoma cells death.