ABSTRACT
In this article, the synthesis of antioxidant peptides in the enzymatic hydrolysis of caprine casein was analyzed at three different time points (60 min, 90 min, and 120 min) using immobilized pepsin on activated and modified carbon (AC, ACF, ACG 50, ACG 100). The immobilization assays revealed a reduction in the biocatalysts' activity compared to the free enzyme. Among the modified ones, ACG 50 exhibited greater activity and better efficiency for reuse cycles, with superior values after 60 min and 90 min. Peptide synthesis was observed under all studied conditions. Analyses (DPPH, ß-carotene/linoleic acid, FRAP) confirmed the antioxidant potential of the peptides generated by the immobilized enzyme. However, the immobilized enzyme in ACG 50 and ACG 100, combined with longer hydrolysis times, allowed the formation of peptides with an antioxidant capacity greater than or equivalent to those generated by the free enzyme, despite reduced enzymatic activity.
Subject(s)
Antioxidants , Caseins , Enzymes, Immobilized , Glutaral , Goats , Iridoids , Pepsin A , Peptides , Antioxidants/chemistry , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Caseins/chemistry , Animals , Pepsin A/metabolism , Pepsin A/chemistry , Glutaral/chemistry , Peptides/chemistry , Iridoids/chemistry , Hydrolysis , Charcoal/chemistryABSTRACT
Alzheimer's disease is associated with protein aggregation, oxidative stress, and the role of acetylcholinesterase in the pathology of the disease. Previous investigations have demonstrated that geniposide and harpagoside protect the brain neurons, and cerium nanoparticles (CeO2 NPs) have potent redox and antioxidant properties. Thus, the effect of nanoparticles of Ce NPs and geniposide and harpagoside (GH/CeO2 NPs) on ameliorating AD pathogenesis was established on AlCl3-induced AD in mice and an aggregation proteins test in vitro. Findings of spectroscopy analysis have revealed that GH/CeO2 NPs are highly stable, nano-size, spherical in shape, amorphous nature, and a total encapsulation of GH in cerium. Treatments with CeO2 NPs, GH/CeO2 NPs, and donepezil used as positive control inhibit fibril formation and protein aggregation, protect structural modifications in the BSA-ribose system, have the ability to counteract Tau protein aggregation and amyloid-ß1-42 aggregation under fibrillation condition, and are able to inhibit AChE and BuChE. While the GH/CeO2 NPs, treatment in AD induced by AlCl3 inhibited amyloid-ß1-42, substantially enhanced the memory, the cognition coordination of movement in part AD pathogenesis may be alleviated through reducing amyloidogenic pathway and AChE and BuChE activities. The findings of this work provide important comprehension of the chemoprotective activities of iridoids combined with nanoparticles. This could be useful in the development of new therapeutic methods for the treatment of neurodegenerative diseases.
Subject(s)
Acetylcholinesterase , Alzheimer Disease , Cerium , Iridoids , Neuroprotective Agents , Cerium/chemistry , Cerium/pharmacology , Iridoids/pharmacology , Iridoids/chemistry , Animals , Neuroprotective Agents/pharmacology , Neuroprotective Agents/chemistry , Mice , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Acetylcholinesterase/metabolism , Amyloid beta-Peptides/metabolism , Male , Nanoparticles/chemistry , Metal Nanoparticles/chemistry , Disease Models, AnimalABSTRACT
A food dye from a South American fruit has become a test case for the ethical development of natural resources.
Subject(s)
Food Coloring Agents , Fruit , Iridoids , Rubiaceae , Fruit/chemistry , Natural Resources , Food Coloring Agents/chemistry , Food Coloring Agents/isolation & purification , Rubiaceae/chemistry , Iridoids/chemistry , Iridoids/isolation & purificationABSTRACT
Inulin-type fructans with different degrees of polymerization (DPs) were used as wall materials for the blue colorant produced from the crosslinking between genipin and milk proteins. The impact of using fructooligosaccharides (FOS) with DP = 5 and inulins with DP ≥ 10 (GR-In) and DP ≥ 23 (HP-In) on the physical (microstructure, size, water activity, wettability, solubility, water adsorption, glass transition temperature, and color), chemical (free genipin retention and moisture), and technological (colorant power, pH stability, and thermal stability) properties of the powdered blue colorant was examined. Inulins were more efficient carriers as seen from the physical characteristics of the microparticles. FOS and GR-In promoted higher retention of free genipin than HP-In. Additionally, their lower DP influenced the rehydration proprieties as well as the color intensity and colorant power. The DP did not affect the physical stability of the colorant at different pH conditions or at high temperature. Our findings demonstrated that the DP of the fructan exhibited a strong impact on the blue intensity of the samples and also their rehydration capacity.
Subject(s)
Coloring Agents/chemistry , Fructans/chemistry , Iridoids/chemistry , Milk Proteins/chemistry , Chemical Phenomena , Humans , Inulin/chemistry , Oligosaccharides/chemistry , Particle Size , Polymerization , Powders/chemistry , Solubility , Temperature , Water , WettabilityABSTRACT
The objective of this research was to evaluate the immobilization of the enzyme ß-galactosidase in a genipin-activated chitosan support. The influence of the number of spheres and substrate concentration on immobilization yield (IY) and enzyme activity (EA) was analyzed using experimental design. Thermal, operational and storage stabilities were assessed, and the enzymatic derivatives were characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The TGA showed that the enzymatic derivatives kept their thermal behavior, and the SEM images revealed smooth surfaces in all the spheres. The optimized conditions for the immobilization process were 4.57 mg·mL-1 of spheres and a substrate concentration of 10 mM (IY = 84.13%; EA = 24.97 U·g-1). Thermal stability was enhanced at 10 and 37 °C, enabling four successive cycles of lactose hydrolysis in diluted UHT milk. Therefore, the immobilized enzyme in genipin-activated chitosan has potential for lactose hydrolysis and applications in the food industry.
Subject(s)
Chitosan/chemistry , Enzymes, Immobilized/chemistry , Iridoids/chemistry , Kluyveromyces/enzymology , Milk/chemistry , beta-Galactosidase/chemistry , Animals , Enzyme Stability , Enzymes, Immobilized/metabolism , Hydrolysis , Lactose/chemistry , beta-Galactosidase/metabolismABSTRACT
Pharmacodynamic interactions between plant isolated compounds are important to understand the mode of action of an herbal extract to formulate or create better standardized extracts, phytomedicines, or phytopharmaceuticals. In this work, we propose binary mixtures using a leader compound to found pharmacodynamic interactions in inhibition of the NF-κB/AP-1 pathway using RAW-Blue™ cells. Eight compounds were isolated from Castilleja tenuiflora, four were new furofuran-type lignans for the species magnolin, eudesmin, sesamin, and kobusin. Magnolin (60.97%) was the most effective lignan inhibiting the NF-κB/AP-1 pathway, followed by eudesmin (56.82%), tenuifloroside (52.91%), sesamin (52.63%), and kobusin (45.45%). Verbascoside, a major compound contained in wild C. tenuiflora showed an inhibitory effect on NF-κB/AP-1. This polyphenol was chosen as a leader compound for binary mixtures. Verbacoside-aucubin and verbascoside-kobusin produced synergism, while verbascoside-tenuifloroside had subadditivity in all concentrations. Verbascoside-kobusin is a promising mixture to use on NF-κB/AP-1 related diseases and anti-inflammatory C. tenuiflora-based phytomedicines.
Subject(s)
Anti-Inflammatory Agents , Glucosides , Iridoids , Lignans , NF-kappa B/antagonists & inhibitors , Orobanchaceae/chemistry , Phenols , Transcription Factor AP-1/antagonists & inhibitors , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Cell Line , Glucosides/chemistry , Glucosides/pharmacology , Iridoids/chemistry , Iridoids/pharmacology , Lignans/chemistry , Lignans/pharmacology , Mice , NF-kappa B/metabolism , Phenols/chemistry , Phenols/pharmacology , Transcription Factor AP-1/metabolismABSTRACT
Wound repair is a complex process that calls for strategies to allow a rapid and effective regeneration of injured skin, which has stimulated the research of advanced wound dressings. Herein, highly porous membranes of N,O-carboxymethylchitosan (CMCh), and poly (vinyl alcohol) (PVA) were successfully prepared via a green and facile freeze-drying method of blend solutions containing CMCh/PVA at weight ratio 25/75. Membranes composed only by CMCh were also prepared and genipin was used for crosslinking. Different contents of TiO2 nanoparticles were incorporated to both type of membranes, which were characterized in terms of morphology, porosity (Φ), swelling capacity (S.C.), mechanical properties, susceptibility to lysozyme degradation and in vitro cytotoxicity toward human fibroblast (HDFn) and keratinocytes (HaCaT) cells. Larger apparent pores were observed in the surface of the genipin-crosslinked CMCh membrane, which resulted in higher porosity (Φ ≈ 76%) and swelling capacity (S.C. ≈ 1720%) as compared to CMCh/PVA membrane (Φ ≈ 68%; S.C. ≈ 1660%). The porosity of both types of membranes decreased upon the addition of TiO2 nanoparticles while swelling capacity increased. Due to their high porosity and swelling capacity, adequate mechanical properties, controlled degradability, and cytocompatibility, such carboxymethylchitosan-based membranes are potentially useful as wound dressings.
Subject(s)
Bandages , Chitosan/analogs & derivatives , Membranes, Artificial , Wound Healing/drug effects , Cell Death , Cell Survival/drug effects , Chitosan/pharmacology , Cross-Linking Reagents/chemistry , Fibroblasts/cytology , Fibroblasts/drug effects , HaCaT Cells , Humans , Iridoids/chemistry , Keratinocytes/cytology , Keratinocytes/drug effects , Muramidase/metabolism , Polyvinyl Alcohol/chemistry , Porosity , Spectrometry, X-Ray Emission , Stress, Mechanical , Titanium/chemistryABSTRACT
The production of extra virgin olive oil (EVOO) in Brazil developed quite recently, and information on commercial Brazilian EVOO's typical features is very scarce. In just one of the previously published works on Brazilian olive oil, the assessed samples were commercially available. In this study, a comprehensive characterization of EVOO samples acquired at local stores (at Rio de Janeiro and Rio Grande do Sul, from the two most prevalent cultivars, Arbequina and Koroneiki) was carried out considering the most relevant quality parameters, antioxidant capacity, oxidative stability, total phenolic content, fatty acid composition, and minor component metabolic profiling. The latter included: (1) the determination of individual phenolic compounds (belonging to four diverse chemical classes) and triterpenic acids by means of a powerful multi-class reversed-phase LC-MS method; (2) the quantitative profiling of tocopherols, phytosterols, and pigments by normal-phase LC-DAD/fluorescence; and (3) the quantitative appraisal of the volatile pattern of the oils by solid-phase microextraction (SPME)-gas chromatography (GC)-MS. By applying these methods, the concentrations of approximately 70 minor compounds were determined in commercial EVOOs from Brazil. To the best of our knowledge, the content of a very large number of phenolic compounds of those determined in the current report (mainly secoiridoids), the three triterpenic acids (maslinic, betulinic, and oleanolic acids), and the individual chlorophyll derivatives had not been previously evaluated in Brazilian EVOOs. The present work provides a broad picture of the compositional profile and other parameters of relevance of selected commercial Brazilian EVOOs available on local markets, describing their typicity and most particular features, some of which are known to have potential impacts on consumers' health.
Subject(s)
Olive Oil/chemistry , Plant Extracts/chemistry , Antioxidants/chemistry , Brazil , Fatty Acids/chemistry , Humans , Industrial Oils/analysis , Iridoids/chemistry , Metabolome , Phenols/chemistry , Solid Phase Microextraction , Sterols/chemistry , Tandem Mass Spectrometry , Tocopherols/chemistry , Triterpenes/chemistry , Volatile Organic Compounds/chemistryABSTRACT
Matricaria chamomilla L. has been used for centuries in many applications, including antiparasitic activity. Leishmaniasis is a parasitic disease, with limited treatments, due to high cost and toxicity. Thus, there is a need to develop new treatments, and in this context, natural products are targets of these researches. We report the development of chitosan nanocapsules containing essential oil of M. chamomilla (CEO) from oil-in-water emulsions using chitosan modified with tetradecyl chains as biocompatible shell material. The nanocapsules of CEO (NCEO) were analyzed by optical microscopy and dynamic light scattering, which revealed spherical shape and an average size of 800 nm. Successful encapsulation of CEO was further confirmed by fluorescence microscopy observations taking advantage of the autofluorescence properties of CEO. The encapsulation efficiency was around 90%. The entrapment of CEO reduced its cytotoxicity towards normal cells. On the other hand, the CEO was active against promastigotes and intracellular amastigotes, exhibiting IC50 of 3.33 µg/mL and 14.56 µg/mL, respectively, while NCEO showed IC50 for promastigotes of 7.18 µg/mL and for intracellular amastigotes of 14.29 µg/mL. These results demonstrate that encapsulation of CEO in nanocapsules using an alkylated chitosan biosurfactant as a "green" stabilizer is a promising therapeutic strategy to treat leishmaniasis.
Subject(s)
Anti-Infective Agents/pharmacology , Chitosan/chemistry , Leishmania/drug effects , Leishmaniasis, Cutaneous/drug therapy , Matricaria/chemistry , Nanocapsules/chemistry , Oils, Volatile/pharmacology , Anti-Infective Agents/chemistry , Cell Line , Chitosan/analogs & derivatives , Chitosan/chemical synthesis , Drug Carriers/chemistry , Dynamic Light Scattering , Humans , Iridoids/chemistry , Keratinocytes/drug effects , Macrophages/drug effects , Microscopy, Fluorescence , Particle Size , Surface TensionABSTRACT
The crude drug ysypó hû (Adenocalymma marginatum DC., Bignoniaceae) is used traditionally by the Guarani of Eastern Paraguayan as a male sexual enhancer. The aim of the present study was to identify the main constituents of the crude drug and to evaluate the in vitro inhibitory activity towards the enzyme phosphodiesterase-5 (PDE-5). The main compounds were isolated by counter-current chromatography (CCC). The metabolites were identified by spectroscopic and spectrometric means. The chemical profiling of the extracts was assessed by high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS/MS). The crude extract and main isolated compounds were tested for their PDE-5 inhibitory activity using commercial kits. The iridoid theviridoside and 4-hydroxy-1-methylproline were isolated as the main constituent of the crude drug. Four chlortheviridoside hexoside derivatives were detected for the first time as natural products. Chemical profiling by HPLC-MS/MS led to the tentative identification of nine iridoids, six phenolics, and five amino acids. The crude extracts and main compounds were inactive towards PDE-5 at concentrations up to 500 µg/mL. Iridoids and amino acid derivatives were the main compounds occurring in the Paraguayan crude drug. The potential of ysypó hû as a male sexual enhancer cannot be discarded, since other mechanisms may be involved.
Subject(s)
Bignoniaceae/chemistry , Iridoids/chemistry , Phosphodiesterase 5 Inhibitors/chemistry , Plant Extracts/chemistry , Amino Acids/analysis , Amino Acids/chemistry , Amino Acids/isolation & purification , Bignoniaceae/metabolism , Chromatography, High Pressure Liquid , Complex Mixtures , Countercurrent Distribution , Iridoid Glycosides , Iridoids/analysis , Iridoids/isolation & purification , Paraguay , Phenols/analysis , Phenols/chemistry , Phenols/isolation & purification , Phosphodiesterase 5 Inhibitors/metabolism , Plant Extracts/isolation & purification , Plant Extracts/metabolism , Tandem Mass SpectrometryABSTRACT
Olive leaves extract (OLE) was spray-dried with maltodextrin (MD) or inulin (IN) to study the evolution of oleuropein (OE) during in vitro gastrointestinal digestion, its bioaccessibility and potential bioavailability. In the case of OLE-MD, OE was partially degraded in gastric and intestinal conditions; whereas in OLE-IN, OE was released under gastric conditions and partially degraded under intestinal conditions. In both cases, the encapsulation of OLE led to higher OE contents at the end of digestion, compared with non-encapsulated OLE, suggesting a protective role of the polysaccharides by the formation of non-covalent polysaccharides-OE complexes. OE bioaccessibility was ten times higher (p ≤ 0.05) in OLE-MD and OLE-IN than in non-encapsulated OLE. However, OE potential bioavailability, evaluated by tangential filtration, was not detected. Encapsulation technology and the encapsulant agent used may determine the release of the encapsulated compounds at a specific-site and their effect on health.
Subject(s)
Biological Products/chemistry , Inulin/chemistry , Iridoids/pharmacokinetics , Polysaccharides/chemistry , Biological Availability , Digestion , Inulin/metabolism , Inulin/pharmacokinetics , Iridoid Glucosides , Iridoids/chemistry , Plant Leaves/chemistry , Polysaccharides/pharmacokineticsABSTRACT
Stress is an important factor in the etiology of some illnesses such as gastric ulcers and depression. Castilleja tenuiflora Benth. (Orobanchaceae) is used in Mexican traditional medicine for the treatment of gastrointestinal diseases and nervous disorders. Previous studies indicated that organic extracts from C. tenuiflora had gastroprotective effects and antidepressant activity. In this study, we aimed to evaluate the gastroprotective and antidepressant activity of fractions and isolated compounds from the methanolic extract (MECt) of C. tenuiflora in stressed mice. Chromatographic fractionation of MECt produced four fractions (FCt-1, FCt-2, CFt-3, and FCt-4) as well as four bioactive compounds which were identified using TLC, HPLC and NMR analyses. The cold restraint stress (CRS)-induced gastric ulcer model followed by the tail suspension test and the forced swim test were used to evaluate the gastroprotective effect and antidepressant activity of the extract fractions. FCt-2 and FCt-3 at 100 mg/kg had significant gastroprotective and antidepressant effects. All isolated compounds (verbascoside, teniufloroside and mixture geniposide/ musseanoside) displayed gastroprotective effects and antidepressant activity at 1 or 2 mg/kg. The above results allow us to conclude that these polyphenols and iridoids from C. tenuiflora are responsible for the gastroprotective and antidepressant effects.
Subject(s)
Iridoids/therapeutic use , Orobanchaceae/chemistry , Plant Extracts/therapeutic use , Animals , Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/therapeutic use , Antidepressive Agents/chemistry , Antidepressive Agents/therapeutic use , Chromatography, High Pressure Liquid , Glucosides/chemistry , Iridoids/chemistry , Male , Methanol/chemistry , Mice , Phenols/chemistry , Plant Extracts/chemistry , Stomach Ulcer/drug therapyABSTRACT
The berries from the native Chilean Gaultheria phillyreifolia and G. poeppigii are appreciated for their sweet taste and aroma. Fruits from both species were investigated for their secondary metabolite composition and antioxidant activity. The extracts were submitted to membrane chromatography to separate anthocyanins from copigments. Four anthocyanins were isolated by counter-current chromatography (CCC) and identified as cyanidin galactoside, cyanidin arabinoside, delphinidin galactoside and delphinidin arabinoside. From the copigments, CCC allowed the separation of quercetin(Q)-3-arabinoside, Q-3-rutinoside Q-3-rhamnoside and 3-caffeoylquinic acid. Additionally, the iridoids monotropein-10-trans-coumarate, monotropein-10-trans-cinnamate and 6α-hydroxy-dihydromonotropein-10-trans-cinnamate were isolated. The latter two iridoids are reported here for the first time. Some 34 other compounds were tentatively identified by HPLC-DAD-ESI-MSn. The antioxidant activity showed differences between anthocyanins and copigments from both species. Main compounds were quantified and submitted to a Partial-Least Square Discriminant Analysis (PLS-DA). This is the first report on the isolation of phytochemicals from the selected Chilean Gaultheria species.
Subject(s)
Antioxidants/chemistry , Gaultheria/chemistry , Iridoids/chemistry , Polyphenols/chemistry , Chile , Chromatography, High Pressure Liquid , Countercurrent Distribution , Discriminant Analysis , Fruit/chemistry , Fruit/metabolism , Gaultheria/metabolism , Iridoids/isolation & purification , Least-Squares Analysis , Plant Extracts/chemistry , Polyphenols/isolation & purification , Spectrometry, Mass, Electrospray IonizationABSTRACT
Olive leaves contain higher amount of polyphenols than olive oil and represent a waste product from olive harvest and pruning of olive trees. The most abundant compound in olive leaves is oleuropein. Benefits of the topical application of olive leaves extract were previously reported, but little information is available on its photoprotective potential and the result of the association of this extract with organic UV filters in topical sunscreen formulations. The olive leaves extract photoprotective potential is less explored for both oral and topical photoprotection in comparison with other plants extracts and polyphenols, such as Polypodium leucotomos extract and resveratrol. There are increasing efforts towards developing more efficient sunscreens and a photoprotection assessement along with a better understanding of the photochemistry of naturally occurring sunscreens could aid the design of new and improved commercial sunscreen formulations. This study was designed to investigate the photoprotective potential of olive leaves extract standardized for oleuropein performing a set of in vitro and in silico tools as an innovative approach, highlighting yeast assays, in vitro Sun Protection Factor (SPF) and molecular modelling studies of UV absorption. This study supports the use of olive leaves extract for photoprotection, as an effective photoprotective, anti-mutagenic and antioxidant active, also showing a synergistic effect in association with UV filters with an improvement on in vitro SPF of sunscreen formulations.
Subject(s)
Iridoids/chemistry , Olea/chemistry , Plant Extracts/chemistry , Sunscreening Agents/chemistry , Antioxidants/chemistry , Iridoid Glucosides , Iridoids/isolation & purification , Models, Molecular , Olea/metabolism , Plant Leaves/chemistry , Plant Leaves/metabolism , Quantum Theory , Sun Protection Factor , Sunscreening Agents/isolation & purification , Ultraviolet RaysABSTRACT
Large segments of the Brazilian population still suffer from malnutrition and diet-related illnesses. In contrast, many native fruits have biodiversity and are underexploited sources of bioactive compounds and unknown to consumers. The phytochemical composition of nine underexplored Brazilian fruits was determined. Carotenoids and anthocyanins were identified and quantified by high performance liquid chromatography-photodiode array-tandem mass spectrometry (HPLC-PDA-MS/MS), and phenolic compounds and iridoids were identified by flow injection analysis-electrospray-ion trap-tandem mass spectrometry (FIA-ESI-IT-MS/MS); in total, 84 compounds were identified. In addition, the chemical structure and pathway mass fragmentation of new iridoids from jenipapo ( Genipa americana) and jatoba ( Hymenae coubaril) are proposed. The highest level of carotenoids was registered in pequi ( Caryocar brasiliense; 10156.21 µg/100 g edible fraction), while the major total phenolic content was found in cambuci ( Campomanesia coubaril; 221.70 mg GAE/100 g). Anthocyanins were quantified in jabuticaba ( Plinia cauliflora; 45.5 mg/100 g) and pitanga ( Eugenia uniflora; 81.0 mg/100 g). Our study illustrates the chemical biodiversity of underexplored fruits from Brazil, supporting the identification of new compounds and encouraging the study of more food matrixes not yet investigated.
Subject(s)
Fruit/chemistry , Phytochemicals/analysis , Anthocyanins/analysis , Biodiversity , Brazil , Carotenoids/analysis , Chromatography, High Pressure Liquid , Diet , Iridoids/analysis , Iridoids/chemistry , Mass Spectrometry , Nutritive Value , Phenols/analysis , Tropical ClimateABSTRACT
An olive leaf extract (OLE) was microencapsulated with sodium alginate (SA) by spray-drying to study the evolution of oleuropein (ORP) during in vitro gastrointestinal digestion, and its bioaccessibility and potential bioavailability from OLE and OLE-SA microparticles. Secoiridoids, flavonoids, simple phenols, oleosides and elenolic acid were identified in OLE. OLE/SA ratio 1:1.6 and inlet air temperature 135⯰C were the optimal conditions for OLE-SA microparticles. ORP (70%) from OLE was degraded during gastric digestion, giving hydroxytyrosol and ORP-aglycone, whereas only the superficial ORP was released from microparticles. The remaining ORP from OLE was degraded under intestinal conditions, leading to oleosides; whereas alginate was swollen and disintegrated, releasing the ORP (90% of encapsulated ORP). ORP from both OLE and microparticles was degraded to hydroxytyrosol under colonic conditions. Encapsulation of OLE allowed the protection of ORP under gastric conditions and its controlled release at intestinal conditions, and higher bioaccessibility (58%) and potential bioavailability (20%).
Subject(s)
Desiccation/methods , Olea/chemistry , Phenols/chemistry , Plant Extracts/chemistry , Alginates/chemistry , Chromatography, High Pressure Liquid , Iridoid Glucosides , Iridoids/chemistry , Olea/metabolism , Phenols/metabolism , Plant Leaves/chemistry , Plant Leaves/metabolism , Spectrometry, Mass, Electrospray Ionization , TemperatureABSTRACT
BACKGROUND: Leishmaniasis reaches millions of people around the world. The control of the disease is difficult due to the restricted access to the diagnosis and medication, and low adherence to the treatment. Thus, more efficient drugs are needed and natural products are good alternatives. Iridoids, natural products with reported leishmanicidal activity, can be exploited for the development of anti- Leishmania drugs. The aim of this study was to isolate and to investigate the in vitro activity of iridoids against Leishmania amazonensis and to compare the activity in silico of these compounds with those reported as active against this parasite. METHODS: Iridoids were isolated by chromatographic methods. The in vitro activity of asperuloside (1) and geniposide (2) from Escalonia bifida, galiridoside (3) from Angelonia integerrima and theveridoside (4) and ipolamiide (5) from Amphilophium crucigerum was investigated against promastigote forms of Leishmania amazonensis. Molecular modeling studies of 1-5 and iridoids cited as active against Leishmania spp. were performed. RESULTS: Compounds 1-5 (5-100 µM) did not inhibit the parasite survival. Physicochemical parameters predicted for 1-5 did not show differences compared to those described in literature. The SAR and the pharmacophoric model confirmed the importance of maintaining the cyclopentane[C]pyran ring of the iridoid, of oxygen-linked substituents at the C1 and C6 positions and of bulky substituents attached to the iridoid ring to present leishmanicidal activity. CONCLUSION: The results obtained in this study indicate that iridoids are a promising group of secondary metabolites and should be further investigated in the search for new anti-Leishmania drugs.
Subject(s)
Antiprotozoal Agents/pharmacology , Iridoids/pharmacology , Leishmania/drug effects , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Computer Simulation , Iridoids/chemistry , Iridoids/isolation & purification , Magnoliopsida , Models, Molecular , Plant Extracts/chemistry , Plant Extracts/pharmacologyABSTRACT
Enzyme-assisted extraction in liquid-liquid two-phase aqueous system was applied for the first time in order to extract genipin from genipap. The effect of different commercial enzymes, their concentrations, and extraction parameters were investigated. Moreover, chitosan gels were prepared, crosslinked with glutaraldehyde or genipin and characterized by their textural and rheological properties. The crosslinked chitosan was used as support for the immobilization of model ß-galactosidases. Among the different commercial enzymes tested for extraction, Celluclast 10% (36⯰C and pH 3.7) provided an extraction of 196â¯mg.g-1 of genipin. Chitosan gels crosslinked with genipin 0.5% showed better textural and similar rheological properties when compared to the chitosan crosslinked with glutaraldehyde 3%. The percentage of lactose hydrolysis by the immobilized K. lactis ß-galactosidase using genipin as a crosslinker was 87%. Thus, the genipin obtained in this work proved to be an excellent alternative to the use of glutaraldehyde in chitosan crosslinking applications.
Subject(s)
Chitosan/chemistry , Cross-Linking Reagents/chemistry , Gardenia/chemistry , Gels/chemistry , Iridoids/chemistry , Iridoids/isolation & purification , Enzymes, Immobilized , Glutaral , Rheology , beta-Galactosidase/metabolismABSTRACT
Plant-derived products have played a fundamental role in the development of new therapeutic agents. This study aimed to analyze antimicrobial, antibiofilm, cytotoxicity and antiproliferative potentials of the extract and fractions from leaves of Himatanthusdrasticus, a plant from the Apocynaceae family. After harvesting, H. drasticus leaves were macerated and a hydroalcoholic extract (HDHE) and fractions were prepared. Antimicrobial tests, such as agar-diffusion, Minimum Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) were carried out against several bacterial species. Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes and Klebsiella pneumoniae were inhibited by at least one extract or fraction in the agar-diffusion assay (inhibition halos from 12 mm to 30 mm). However, the lowest MIC value was found for HDHE against K. pneumoniae. In addition, HDHE and its fractions were able to inhibit biofilm formation at sub-inhibitory concentrations (780 µg/mL and 1.56 µg/mL). As the best activities were found for HDHE, we selected it for further assays. HDHE was able to increase ciprofloxacin (CIP) activity against K. pneumoniae, displaying synergistic (initial concentration CIP + HDHE: 2 µg/mL + 600 µg/mL and 2.5 µg/mL + 500 µg/mL) and additive effects (CIP + HDHE: 3 µg/mL + 400 µg/mL). This action seems to be associated with the alteration in bacterial membrane permeability induced by HDHE (as seen by propidium iodide labeling). This extract was non-toxic for red blood cell or human peripheral blood mononuclear cells (PBMCs). Additionally, it inhibited the lipopolysaccharide-induced proliferation of PBMCs. The following compounds were detected in HDHE using HPLC-ESI-MS analysis: plumieride, plumericin or isoplumericin, rutin, quercetin and derivatives, and chlorogenic acid. Based on these results we suggest that compounds from H. drasticus have antimicrobial and antibiofilm activities against K. pneumoniae and display low cytotoxicity and anti-proliferative action in PBMC stimulated with lipopolysaccharide.
Subject(s)
Anti-Infective Agents/chemistry , Apocynaceae/chemistry , Biofilms/drug effects , Flavonoids/chemistry , Furans/chemistry , Iridoids/chemistry , Plant Leaves/chemistry , Anti-Infective Agents/isolation & purification , Anti-Infective Agents/pharmacology , Biofilms/growth & development , Cell Membrane Permeability/drug effects , Cell Survival/drug effects , Ciprofloxacin/pharmacology , Drug Combinations , Drug Synergism , Erythrocytes/cytology , Erythrocytes/drug effects , Flavonoids/isolation & purification , Flavonoids/pharmacology , Furans/isolation & purification , Furans/pharmacology , Iridoids/isolation & purification , Iridoids/pharmacology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/physiology , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Listeria monocytogenes/drug effects , Listeria monocytogenes/physiology , Microbial Sensitivity Tests , Plant Extracts/chemistry , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/physiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiologyABSTRACT
Three new coumarins (1-3), a prenylated flavanone (4), and two iridoids (5 and 6), together with 17 known secondary metabolites, were isolated from the aerial parts of Arcytophyllum thymifolium. The structures of the new compounds were elucidated on the basis of their spectroscopic data. The potential hypoglycemic properties of the new and known compounds were evaluated by measuring their α-amylase and α-glucosidase inhibitory effects. The iridoid asperulosidic acid (15) and the flavonoid rhamnetin (13) showed the highest activities versus α-amylase (IC50 = 69.4 ± 3.1 and 73.9 ± 5.9 µM, respectively). In turn, the new eriodictyol derivative 4 exhibited the most potent effect as an α-glucosidase inhibitor, with an IC50 value of 28.1 ± 2.6 µM, and was more active than acarbose, used as a positive control. Modeling studies were also performed to suggest the interaction mode of compound 4 in the α-glucosidase enzyme active site.