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1.
Five landraces of Smallanthus sonchifolius [(Poepp. and Endl.) H. Robinson], known as yacon, were investigated in total phenolic content, antioxidant activity and chemical composition of ethanol extracts (EEs) and decoction extracts (DEs). The results demonstrated that DEs are rich in phenolic acids as caffeic acid, while the EEs show an higher amount of flavonoids, as luteolin 3′,7-O-diglucoside and luteolin 7-O-glucoside. These flavonoid glycosides were identified for the first time in yacon extracts, together with apigenin and luteolin. The phytochemical profile explains the different antioxidant activities shown in our study. The landraces PER6-DE and PER4-DE showed the highest radical-scavenging activity and reducing power related to their polyphenolic contents. Results also show that yacon can be considered an important source of bioactive compounds with significant differences among the analysed landraces.  相似文献   

2.
Luteolin and apigenin derivatives present in oil palm (Elaeis guineensis) leaves (OPL) are reported to possess excellent antioxidant properties relating to numerous health benefits. To meet the global demand for flavonoids, OPL, which is plentifully generated as an agricultural by-product from oil palm plantations, can be further exploited as a new source of natural antioxidant compounds. However, to produce a standardized herbal preparation, validation of the quantification method for these compounds is required. Therefore, in this investigation, we developed and validated an improved and rapid analytical method, ultra-high-performance liquid chromatography equipped with ultraviolet/photodiode array (UHPLC-UV/PDA) for the quantification of 12 luteolin and apigenin derivatives, particularly focusing on flavonoid isomeric pairs: orientin/isoorientin and vitexin/isovitexin, present in various OPL extracts. Several validation parameters were assessed, resulting in the UHPLC-UV/PDA technique offering good specificity, linearity, accuracy, precision, and robustness, where the values were within acceptable limits. Subsequently, the validated method was employed to quantify luteolin and apigenin derivatives from OPL subjected to different drying treatments and extraction with various solvent systems, giving total luteolin (TLC) and apigenin content (TAC) in the range of 2.04–56.30 and 1.84–160.38 µg/mg extract, respectively. Additionally, partial least square (PLS) analysis disclosed the combination of freeze dry-aqueous methanol yielded OPL extracts with high TLC and TAC, which are strongly correlated with antioxidant activity. Therefore, we provide the first validation report of the UHPLC-UV/PDA method for quantification of luteolin and apigenin derivatives present in various OPL extracts, suggesting that this approach could be employed in standardized herbal preparations by adopting orientin, isoorientin, vitexin, and isovitexin as chemical markers.  相似文献   

3.
The purpose of this work was to evaluate chemical constituents, antioxidant and antimicrobial activities of Artabotrys hildebrandtii, an endemic medicinal plant from Madagascar. Ethanol extracts from the leaves and stem bark were tested to evaluate DPPH free radical scavenging, using butylated hydroxytoluene and quercetin as standard antioxidants. An high-performance liquid chromatography/mass spectrometry method was developed to investigate the presence of phenolic compounds in the studied samples; gentisic acid, chlorogenic acid, hyperoside, isoquercitrin, rutin, quercitrin, quercetol, apigenin and luteolin were identified. Total polyphenolic content was determined by a spectrophotometric method using Folin–Ciocâlteu reagent. Results showed the efficiency of A. hildebrandtii leaves extract against strains of Staphylococcus aureus and Listeria monocytogenes, as the inhibitory activity is more powerful compared to Gentamicin, used as the standard drug. The leaves of A. hildebrandtii can be considered an important source of polyphenols, especially of rutin, with good antioxidant and antimicrobial activities.  相似文献   

4.
Miconia chamissois Naudin is a species from the Cerrado, which is being increasingly researched for its therapeutic potential. The aim of this study was to obtain a standardized extract and to evaluate seasonal chemical variations. Seven batches of aqueous extracts from leaves were produced for the standardization. These extracts were evaluated for total solids, polyphenol (TPC) and flavonoid content (TFC), vitexin derivative content, antioxidant activity; thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC) profiles were generated. For the seasonal study, leaves were collected from five different periods (May 2017 to August 2018). The results were correlated with meteorological data (global radiation, temperature, and rainfall index). Using chromatographic and spectroscopic techniques, apigenin C-glycosides (vitexin/isovitexin) and derivatives, luteolin C-glycosides (orientin/isoorientin) and derivatives, a quercetin glycoside, miconioside B, matteucinol-7-O-β-apiofuranosyl (1 → 6) -β-glucopyranoside, and farrerol were identified. Quality parameters, including chemical marker quantification by HPLC, and biological activity, are described. In the extract standardization process, all the evaluated parameters showed low variability. The seasonality study revealed no significant correlations (p < 0.05) between TPC or TFC content and meteorological data. These results showed that it is possible to obtain extracts from M. chamissois at any time of the year without significant differences in composition.  相似文献   

5.
A new dihydrobenzodioxane derivative, origalignanol ( 10 ), together with nine polyphenolic compounds, salvianolic acid A ( 1 ), salvianolic acid C ( 2 ), lithospermic acid ( 3 ), apigenin 7‐O‐β‐D‐glucuronide ( 4 ), apigenin 7‐O‐β‐D‐(6″‐methyl)glucuronide ( 5 ), luteolin, ( 6 ), luteolin 7‐O‐β‐D‐glucopyranoside ( 7 ), luteolin 7‐O‐β‐D‐glucuronide ( 8 ), and luteolin 7‐O‐β‐D‐xylopyranoside ( 9 ), were isolated from the aqueous ethanolic extract of the aerial parts of Origanum vulgare for the first time. The structure of new compound 10 was determined on the basis of spectroscopic methods. Compound 5 is probably an artifact formed during the isolation. Compounds 1, 2 and 3 showed strong DPPH radical scavenging activity with an EC50 of 7.2 ± 0.4, 9.6 ± 0.9, and 9.5 ± 0.7 μM, respectively, and protected rat hepatocytes from CCl4‐damage at 100 μM.  相似文献   

6.
Naringenin 5-O-glucoside, apigenin 7-O-glucoside, luteolin 7-O-glucoside, kaempferol 3-O-glucoside, quercetin 3-O-glucoside, apigenin, luteolin, kaempferol, and quercetin, nine flavonoid derivatives, were isolated for the first time from the aqueous methanolic extract of the aerial parts of Chrysanthemum coronarium. Their structures were elucidated on the basis of chemical and spectroscopic (UV, 1H, 13C NMR) analyses. 1-and 2-dimensional NMR spectroscopy of the rare naringenin 5-O-glucoside have been recorded and assigned for the first time. The flavonoid glucosides from Chrysanthemum coronarium showed week activity against Poliovirus I and Adenovirus type 7. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 546–548, November–December, 2007.  相似文献   

7.
Novel methods for the determination of polyphenolic antioxidants present in extracts from inflorescences of Cirsium vulgare (Savi) Ten. based on ultra‐high performance liquid chromatography with photodiode array and chemiluminescence detection have been developed. Under the optimized conditions of chromatographic separation the analytical characteristic of the method was performed. The proposed method was successfully applied to the determination of ten polyphenols present in inflorescences of Cirsium vulgare . A comparison of the contents of analytes in extracts prepared by using various extraction media (methanol, ethanol, 70% methanol, 70% ethanol, and water) was carried out for the first time. For the postcolumn detection of scavenging activity of polyphenolic antioxidants against reactive oxygen species (H2O2, OH, O2• −) three systems based on chemiluminescence of luminol were used. A review of the current scientific literature shows that this is the first report on the application of luminol‐based postcolumn detection for the on‐line investigation of OH scavenging activity. The main compound determined in extracts from inflorescences of Cirsium vulgare was apigenin 7‐O‐glucuronide, whereas the highest antioxidant activity was observed for chlorogenic acid, luteolin 7‐O‐glucoside, and apigenin.  相似文献   

8.
The chemical composition of the hydroethanolic extracts (60% v/v) from the aerial parts of Thymus marschallianus Willd (TM) and Thymus seravschanicus Klokov (TS) from Southern Kazakhstan flora was analyzed together with their hexane fractions. Determination of antibacterial, antifungal and antioxidant activities of both extracts was also performed. RP-HPLC/PDA and HPLC/ESI-QTOF-MS showed that there were some differences between the composition of both extracts. The most characteristic components of TM were rosmarinic acid, protocatechuic acid, luteolin 7-O-glucoside, and apigenin 7-O-glucuronide, while protocatechuic acid, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, and eriodictyol predominated in TS. The content of polyplenols was higher in TS than in TM. The GC-MS analysis of the volatile fraction of both examined extracts revealed the presence of thymol and carvacrol. Additionally, sesquiterpenoids, fatty acids, and their ethyl esters were found in TM, and fatty acid methyl esters in TS. The antioxidant activity of both extracts was similar. The antibacterial activity of TS extract was somewhat higher than TM, while antifungal activity was the same. TS extract was the most active against Helicobacter pylori ATCC 43504 with MIC (minimal inhibitory concentration) = 0.625 mg/mL, exerting a bactericidal effect. The obtained data provide novel information about the phytochemistry of both thyme species and suggest new potential application of TS as a source of bioactive compounds, especially with anti-H. pylori activity.  相似文献   

9.
The aerial parts of Tephrosia humilis were tested about their antioxidant potential, their ability to inhibit the aldose/aldehyde reductase enzymes and their phenolic content. The plant material was exhaustively extracted with petroleum ether, dichloromethane and methanol, consecutively. The concentrated methanol extract was re-extracted, successively, with diethyl ether, ethyl acetate and n-butanol. All extracts showed significant antioxidant capacity, but the most effective was the ethyl acetate extract. As about the aldose reductase inhibition, all fractions, except the aqueous, were strong inhibitors of the enzyme, with the n-butanolic and ethyl acetate fractions to inhibit the enzyme above 75%. These findings provide support to the ethnopharmacological usage of the plant as antioxidant and validate its potential to act against the long-term diabetic complications. The phytochemical analysis showed the presence of 1,4-dihydroxy-3,4-(epoxyethano)-5-cyclohexene(1), cleroindicin E(2), lupeol(3), methyl p-coumarate(4), methyl 4-hydroxybenzoate(5), prunin(6), 5,7,2?,5?-tetrahydroxyflavanone 7-rutinoside(7), protocatechuic acid(8), luteolin 7-glucoside(9), apigenin(10), naringin(11), rhoifolin(12) and luteolin 7-glucuronate(13).  相似文献   

10.
Phyllanthus fraternus is widely used in the cure of various liver diseases and possess antiviral properties especially against hepatitis virus. In the present study, evaluation of the antioxidant activity of stem and calli induced from stem has been done by different assays. Extraction was done by standard method in water and ethanol. Total antioxidant capacity was measured by 1, 1-diphenyl-2-picrylhydrazyl free radical scavenging method. Lipid peroxidation was measured in terms of thiobarbituric acid-reactive substances (TBARS) by using egg yolk homogenates as lipid-rich media, and superoxide radical scavenging activity was measured using riboflavin–light–nitro blue tetrazolium assay. Reducing power was determined on the basis of Fe3+–Fe2+ transformation in the presence of the extract. In addition to the antioxidant activity, polyphenolic compounds like total phenolics and flavonoids were also measured by spectroscopic method. Results showed that the ethanolic extract of stem is more potent in antioxidant activity than its aqueous extract and ethanolic extract of calli. A significant correlation between antioxidant capacity and polyphenolic content and reducing potential was observed, indicating that phenolic compounds and reducers present in extract are major contributors to the antioxidant potential. Thus, this plant extract could be used as a potent natural antioxidant.  相似文献   

11.
In the quest for new natural agents of photoprotection, we evaluated the photoprotective and antioxidant activity of B. antioquensis leaf extracts as well as its phenolic composition. The methanolic extract treated with activated carbon showed the highest absorption coefficients for UVA‐UVB radiation, as well as an antioxidant capacity comparable to butylated hydroxy toluene. Furthermore, the formulation containing this extract showed suitable sensorial and photostable characteristics for topical use, and significant values of UVAPF, critical wavelength (λc), UVA/UVB ratio and sun protection factor (5.3, 378 nm, 0.78 and 9.1 ± 0.1, respectively). In addition, three glycoside derivatives of quercetin, a kaempferol glycoside and a derivative of caffeic acid were the main polyphenolic compounds identified. These results demonstrate the potential of B. antioquensis extracts to be used as active components of novel, natural sunscreens.  相似文献   

12.
To investigate the bioactive constituents of the inflorescences of Scabiosa comosa and S. tschilliensis, which are used traditionally for liver diseases, we tested the antioxidant activity using 2,2′-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), ferric reducing antioxidant potential (FRAP), and DPPH-ultra high performance liquid chromatography-mass spectrometer (UPLC-MS) assay. In addition, cell-based anti-HCV activity of the major compounds were evaluated. The plant extracts showed strong antioxidant activity. For the first time, 3,4-dicaffeoylquinic acid (DCQA), 3,5-DCQA and 4,5-DCQA were identified from genus Scabiosa. A UPLC-MS method in multiple reaction monitoring (MRM) mode was established to quantify 18 constituents in the inflorescences of Scabiosa. The 3,5-DCQA, chlorogenic acid and some glycosides of luteolin or apigenin were found to be the most abundant constituents. Chlorogenic acid and 3,5-DCQA showed excellent radical scavenging activity and demonstrated anti-HCV activity. These findings provided scientific evidences for the clinic use of this herbal medicine for liver diseases.  相似文献   

13.
Bauhinia forficata Link. is utilised as an antidiabetic in Brazilian folk-medicine; furthermore, its antioxidant properties suggest a potential usefulness in the prevention of diabetes complications associated with oxidative stress. The contribution of a flavonoid-rich fraction (FRF), HPLC-PDA-ESI-MS characterised, to the antioxidant and cytotoxic properties of B. forficata hydro-alcoholic leaves extract was evaluated for the first time. Both extract and FRF showed radical-scavenging activity and reducing power with a strong relationship with the flavonoid content found; hence, flavonoids are mainly responsible for the primary antioxidant activity of B. forficata extract. The extract significantly decreased FO-1 cell viability at the higher concentrations. FRF did not exert any effect; thus, flavonoids do not appear to be responsible for the cytotoxicity of the extract. The extract resulted virtually non-toxic against both Artemia salina and normal human lymphocytes, demonstrating potential selectivity in inhibiting cancer cell growth. Finally, no antimicrobial activity was observed against the bacteria and yeasts tested.  相似文献   

14.
The sterile stems belonging to the Equisetum species are often used in traditional medicine of various nations, including Romanians. They are highly efficient in treating urinary tract infections, cardiovascular diseases, respiratory tract infections, and medical skin conditions due to their content of polyphenolic derivatives that have been isolated. In this regard, this study aimed to provide the chemical composition of the extracts obtained from the Equisetum species (E. pratense, E. sylvaticum, E. telmateia) and to investigate the biological action in vitro and in vivo. For the chemical characterization of the analyzed Equisetum species extracts, studies were performed by using ultra-high-performance liquid chromatography (UHPLC-DAD). In vitro evaluation of the antioxidant activity of the plant extracts obtained from these species of Equisetum genus was determined. The neuroprotective activity of these three ethanolic extracts from the Equisetum species using zebrafish tests was determined in vivo. All obtained results were statistically significant. The results indicate that E. sylvaticum extract has a significant antioxidant activity; whereas, E. pratense extract had anxiolytic and antidepressant effects significantly higher than the other two extracts used. All these determinations indicate promising results for the antioxidant in vitro tests and neuroprotective activity of in vivo tests, particularly mediated by their active principles.  相似文献   

15.
Plant biochemistry studies have increased in recent years due to their potential to improve human health. Argylia radiata is an extremophile plant with an interesting polyphenolic profile. However, its biomass is scarce and occasionally available. Argylia in vitro biomass was obtained from tissue culture and compared with in vivo roots regarding its polyphenolic and flavonoid content. Different solvents were used to prepare extracts from the in vitro tissue of callus and aerial plant organs and in vivo roots. UPLC-MS/MS was used to assess the chemical composition of each extract. ORAC-FL and scavenging of free radicals (DPPH and OH) methods were used to determine the antioxidant capacity of extracts. Furthermore, the biological activity of the extracts was established using the cellular antioxidant activity method. The vitroplants were a good source of polyphenols (25–68 mg GAE/100 g tissue FW), and methanol was the most efficient solvent. Eight polyphenolic compounds were identified, and their antioxidant properties were investigated by different chemical methods with EPR demonstrating its specific scavenging activity against free radicals. All extracts showed cellular dose-dependent antioxidant activity. The methanolic extract of vitroplants showed the highest cellular antioxidant activity (44.6% and 51%) at 1 and 10 µg/mL of extract, respectively. Vitroplants of A. radiata are proposed as a biotechnological product as a source of antioxidant compounds with multiple applications.  相似文献   

16.
The aim of this research was to investigate the chemical composition of Coreopsis tinctoria Nutt. fruits extract, to highlight the potential of ultrasound assisted extraction in the fast preparation of extracts rich in polyphenols using different solvents (55%, 78% and 96% hydrous ethanol) and to evaluate the antioxidant potential of formulated extracts. LC-MS/MS was used to characterize the ethanolic extract from Coreopsis tinctoria Nutt. dried fruits. The extract contains different flavonoids (marein, flavanomarein, quercetagetin-7-O-glucoside, okanin aurone, leptosidin, luteolin, apigenin) and phenolic acids (chlorogenic acid, caffeic acid). Several parameters that could affect extraction efficiency were evaluated. Finally, this study focused on determination of plant extracts total phenolic content and their antioxidant capacity. The experimental results allowed the selection of the optimum operating parameters leading to the highest total polyphenolic content, expressed as gallic acid equivalents, and avoiding the degradation of phenolic compounds (ethanol 55%; extraction temperature 323.15 K, extraction time 30 min, liquid/solid ratio 20/1). A good relationship between total phenolic content and antioxidant capacity was obtained.
  相似文献   

17.
High-performance liquid chromatography with diode array and electrospray ionization mass spectrometric detection was used to carry out the comprehensive characterization of a lemon verbena extract with demonstrated antioxidant and antiinflammatory activity. Two different MS techniques have been coupled to HPLC: on one hand, time-of-flight mass spectrometry, and on the other hand, tandem mass spectrometry on an ion-trap. The use of a small particle size C18 column (1.8 μm) provided a great resolution and made possible the separation of several isomers. The UV–visible spectrophotometry was used to delimit the class of phenolic compound and the accurate mass measurements on time-of-flight spectrometer enabled to identify the compounds present in the extract. Finally, the fragmentation pattern obtained in MS–MS experiments confirmed the proposed structures. This procedure was able to determine many well-known phenolic compounds present in lemon verbena such as verbascoside and its derivatives, diglucuronide derivatives of apigenin and luteolin, and eukovoside. Also gardoside, verbasoside, cistanoside F, theveside, campneoside I, chrysoeriol-7-diglucuronide, forsythoside A and acacetin-7-diglucuronide were found for the first time in lemon verbena.  相似文献   

18.
Aqueous extracts of aerial flowering parts of five Agrimonia species (Rosaceae): Agrimonia coreana Nakai, Agrimonia japonica (Miq.) Koidz, Agrimonia procera Wallr., Agrimonia eupatoria L. and Agrimonia leucantha Kunze were investigated on their antioxidant activity, measured using five different methods; the best was the extract from A. procera with IC50 values from 6 to 29 μg/mL. All the extracts displayed inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) at the tested concentration of 100 μg/mL. We found the highest inhibition of cholinesterase in the extract of A. japonica with inhibition 70.4% for AChE and 79.8% for BuChE. These findings are statistically significant in comparison with those of other extracts (p < 0.001). The phytochemical analyses showed that the antioxidant activity of Agrimonia extracts can be affected especially by hexahydroxydiphenoyl (HHDP)-glucose and quercetin glycosides, and inhibition of cholinesterases by apigenin, luteolin and quercetin glycosides.  相似文献   

19.
Retama sphaerocarpa occurs in the Mediterranean area of North-east Africa and in the Iberian Peninsula, and grows on a variety of soil types and climatic conditions. Used in Algerian folk medicine, it is a valuable species for revegetation and soil restoration. The aim of this study is to evaluate flavonoid composition and antioxidant and antiglycation properties of methanolic and aqueous extracts from R. sphaerocarpa fruits. HPLC-PDA/ESI-MS was used to identify/quantify flavonoid content. Antioxidant activity was evaluated by Folin–Ciocalteu, ORAC, FRAP, TEAC, and DPPH assays, and antiglycation capability by glucose/fructose-BSA assay. Results showed that fruits contain isoflavones (daidzein and genistein derivatives) and flavonols (apigenin, isorhamnetin, kaempferol and quercetin derivatives), and extracts (especially the methanolic one, richer in flavonoids) possess good in vitro antioxidant and antiglycation properties. These findings evidence that R. sphaerocarpa fruits are a source of valuable phytochemicals, with potential applications in the field of phytopharmaceuticals and in food industry.  相似文献   

20.
By-products of Capsicum chinense Jacq., var Jaguar could be a source of bioactive compounds. Therefore, we evaluated the anti-inflammatory effect, antioxidant activity, and their relationship with the polyphenol content of extracts of habanero pepper by-products obtained from plants grown on black or red soils of Yucatán, Mexico. Moreover, the impact of the type of extraction on their activities was evaluated. The dry by-product extracts were obtained by maceration (ME), Soxhlet (SOX), and supercritical fluid extraction (SFE). Afterward, the in vivo anti-inflammatory effect (TPA-induced ear inflammation) and the in vitro antioxidant activity (ABTS) were evaluated. Finally, the polyphenolic content was quantified by Ultra-Performance Liquid Chromatography (UPLC), and its correlation with both bioactivities was analyzed. The results showed that the SFE extract of stems of plants grown on red soil yielded the highest anti-inflammatory effect (66.1 ± 3.1%), while the extracts obtained by ME and SOX had the highest antioxidant activity (2.80 ± 0.0052 mM Trolox equivalent) and polyphenol content (3280 ± 15.59 mg·100 g−1 dry basis), respectively. A negative correlation between the anti-inflammatory effect, the antioxidant activity, and the polyphenolic content was found. Overall, the present study proposed C. chinense by-products as a valuable source of compounds with anti-inflammatory effect and antioxidant activity.  相似文献   

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