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1.
Antioxidant activity, neuroprotective effect and acetylcholinesterase inhibitor activity were studied in acetylated flavones from Galeopsis ladanum L. (Lamiaceae), previously isolated and identified by UV-spectra, UPLC–MS/MS and 1H-NMR spectroscopy. Structure–activity relationships of flavonoids have been determined in many antioxidant assays, generally focused on hydroxyl groups. In this study we have detected new interesting structure–activity relationships for the isolated flavonoids due to the acetylation of sugar moiety of these flavonoids. Methylation at 4′-OH and monoacetylation is beneficial to inhibiting AChE and shows a neouroprotective effect.  相似文献   

2.
The hydrodistilled essential oil obtained from the aerial parts of Daucus guttatus Sibth. & Sm. ssp. zahariadii Heywood, an endemic plant species of the Balkan Peninsula, as well as solvent extracts and essential oils from different parts of Daucus carota L. have been analysed by GC and GC–MS and screened for antimicrobial activity against 12 bacterial and two fungal strains. The volatiles of the two plant taxa differed significantly in both their chemical identity and antimicrobial effect. The dominant constituent of D. guttatus oil was apiol (43.3%), which was absent from all samples of D. carota. The diethyl ether extract of D. carota inhibited the growth of the yeast Candida albicans while the oil of D. guttatus at 25 mg/ml had no effect on the growth of the fungal organisms tested. Additionally, the oil of D. guttatus showed prominent antibacterial activity against a pathogenic Corynebacterium pyogenes.  相似文献   

3.
The influence of different treatments, i.e., crushing, high temperature short time (90 °C/4 min) (HTST) and low temperature long time (60 °C/40 min) (LTLT) blanching, acidification (pH 4.3), and sequences of these treatments on the folate poly-γ-glutamate profile and stability were investigated. In this study, broccoli was used as a case study. Regarding the folate poly-γ-glutamate profile, endogenous folate poly-γ-glutamates in broccoli florets were found predominantly as hepta- and hexa-γ-glutamates. Crushing raw broccoli, acidification and LTLT blanching enhanced folate deconjugation resulting in monoglutamate, di- and tri-γ-glutamates. Compared to other treatments, HTST blanching preformed prior to crushing resulted in the highest concentration of long chain poly-γ-glutamates. Regarding folate poly-γ-glutamates stability, acidification combined with LTLT blanching decreased folate stability whereas HTST blanching combined with different sequences of blanching and crushing did not affect folate poly-γ-glutamates stability. It was concluded that crushing (prior to heating), acidification and blanching could be strategically applied to increase the folate monoglutamate content of broccoli.  相似文献   

4.
Hawthorn (Crataegus spp.) fruits are increasingly popular as raw materials for nutraceuticals and functional foods. As a major group of bio-active components of hawthorn, the phenolic compounds of the fruits have not been well characterized so far. After extraction with 80% aqueous ethanol, the phenolics of the fruits of a major Chinese hawthorn variety, Crataegus pinnatifida Bge. var. major, were separated by polyamide column chromatography, followed by analyses by high performance liquid chromatography combined with diode array UV spectrometry and electrospray ionization mass spectrometry. Ideain (cyanidin-3-O-galactoside), chlorogenic acid, procyanidin B2 [epicatechin-(4β → 8)-epicatechin], epicatechin, hyperoside (quercetin-3-O-galactoside) and isoquercitrin (quercetin-3-O-glucoside) were identified with UV spectra, mass spectra and reference compounds. In addition, 35 compounds were tentatively identified based on UV and mass spectra. These compounds were mostly B-type procyanidins (PA) and their glycosides including aglycons of 3 dimers, 3 trimers, 8 tetramers, 4 pentamers, 2 hexamers and 2 glycosides of PA monomers, 7 glycosides of PA dimers, 1 glycoside of a PA trimer, 2 glycosides of PA tetramers, 1 glycoside of a PA pentamer, and 2 glycosides of quercetin. This is the first systematic study of phenolic compounds in Chinese hawthorn fruits and the first report of the presence of glycosylated procyanidins in hawthorn.  相似文献   

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7.
The effects of the caprine αS1-casein (CSN1S1) polymorphisms on milk quality have been widely demonstrated. However, much less is known about the consequences of the κ-casein (CSN3) genotype on milk composition in goats. Moreover, the occurrence of interactions between CSN3 and CSN1S1 genotypes has not been investigated. In this study, an association analysis between CSN1S1 and CSN3 genotypes and milk quality traits was performed in 89 Murciano-Granadina goats. Total milk yield as well as total protein, fat, solids-not-fat, lactose, αS1-casein (CSN1S1), and αS2-casein (CSN1S2) contents were recorded every other month during a whole lactation (316 observations). Data analysis using a linear mixed model for repeated observations revealed no interaction between the CSN1S1 and CSN3 genotypes. With regard to the effect of the CSN3 locus, AB and BB genotypes were significantly associated with higher levels of total casein and protein content compared with the AA CSN3 genotype. In strong contrast with French breeds, the CSN1S1 genotype did not affect protein, casein, and fat concentrations in Murciano-Granadina goats. These results highlight the importance of taking into consideration the CSN3 genotype when performing selection for milk composition in dairy goats.  相似文献   

8.
当今世界尚未发现烟草CMV抗源,据此,笔者经多年在烟草苗床和大田加压选择,育成三个高耐CMV品系:C151、C152和C212。在自然感染和田间接毒测定中,其抗性均占显著优势,平均病情指数比台湾育成的TT6、TT7低,室内接种鉴定对大陆各烟区CMV病毒株系的耐力远比TT6、TT7强,对各地CMV流行株系表现明显的抗性,达显著和极显著水平。尤其C212,其病情指数为28.88,是三品系中最低者,抗(耐)力居首位。TMV接毒鉴定,C151为过敏枯斑反应,是当前对CMV和TMV兼抗性能的较好桥梁品系。   相似文献   

9.
The kinetics of starch and protein digestion in hammer- and cryo-milled cowpea (70–370 μm) were investigated. The pH during the protein digestion reduced with time, and both the starch and protein digestion exhibited monophasic digestograms, which were suitably (r2 > 0.97, p < 0.001) described by a modified first-order kinetic model. The in vitro protein digestibility of the cowpea (>80%) was independent of the milling conditions. The hammer-milled cowpea digested more, but the reciprocal of its rate of protein digestion was independent of the square of the particle size. The rate of protein digestion in the cryo-milled cowpea inversely depended (p < 0.05) on the square of the particle size, with 67 × 10−7 cm2 s−1 as the diffusion coefficient. For the starch digestion, diffusion coefficients (cm2 s−1) were 0.6 × 10−7 (hammer-milled) and 0.3 × 10−7 (cryo-milled). The protein digestion proceeded at a much faster (100×) rate than the starch digestion.  相似文献   

10.
The objective of this study was to investigate the effects of bovine GH1, CAPN1 and CAST gene polymorphisms on carcass and meat traits in Nellore and Nellore x Bos taurus beef cattle. Three hundred animals were genotyped for GH1/MspI (TC/G in intron 3), CAPN316 (AF_252504.2:g.5709C > G) and CAST/RsaI (AY_008267.1:g282C > G) and phenotyped for rib eye area, backfat thickness, intramuscular fat, shear force (SF), and myofibrillar fragmentation index (MFI). No significant associations were observed between the GH1/MspI and CAST/RsaI polymorphisms and phenotypes, although the relation between the CAST/RsaI genotypes and meat tenderness evaluated by MFI approached significant. The fact that the CAPN316 polymorphism did not show adequate segregation in Nellore cattle confirms the difficulty of using this marker in breeding programs of different Bos indicus breeds. However, the positive results of the association analysis obtained for Nellore x B. taurus crosses contributed to the validation of previous findings.  相似文献   

11.
The objective of this study was to investigate antioxidant activities and anthocyanin profiles in the fruits of Liriope platyphylla, where these are considered functional substances in Korea. The acidic methanol extract of this species exhibited potent antioxidant activities, showing 83.9% DPPH scavenging activity and 92.5% ABTS scavenging activity at a concentration of 0.5 mg/ml. Moreover, anthocyanins were identified by reversed-phase C18 column chromatography, NMR spectroscopy, and HPLC-DAD-ESI/MS analysis. Seven anthocyanins were characterised, including delphinidin-3-O-glucoside (1), delphinidin-3-O-rutinoside (2), cyanidin-3-O-glucoside (3), petunidin-3-O-glucoside (4), petunidin-3-O-rutinoside (5), malvidin-3-O-glucoside (6), and malvidin-3-O-rutinoside (7). Among these, petunidin-3-O-rutinoside (5) (7302.2 μg/g) and malvidin-3-O-rutinoside (7) (5776.1 μg/g) were the predominant anthocyanins, whereas the least prevalent anthocyanin was found to be cyanidin-3-O-glucoside (3) (64.9 μg/g). Therefore, our results suggest that strong antioxidant activities of the acidic methanol extract of L. platyphylla fruits are correlated with high anthocyanin contents, particularly the petunidin-3-O-rutinoside (5) and malvidin-3-O-rutinoside (7).  相似文献   

12.
Bioassay-directed isolation and purification of the ethyl acetate and methanol extracts of Amelanchier canadensis resulted in 1,3-dilinoleoyl 2-olein (1), 1,3-dioleoyl 2-linolein (2), 5-hydroxymethyl-2-furfural (3), 5-(sorbitoloxymethyl)-furan-2-carboxaldehyde (4), 5-(mannitoloxymethyl)-furan-2-carboxaldehyde (5), and 5-(α-d-glucopyranosyloxymethyl) furan-2-carboxaldehyde (6). Four compounds, oleanolic acid (7), ursolic acid (8), kaempferol-3-O-α-l-rhamnopyranosyl (1 ← 2) rhamnopyranoside (9), and kaempferol-3-O-α-l-rhamnopyranoside (10) were isolated from the ethyl acetate extract of fresh fruits of Amelanchier arborea. The compounds were isolated and purified by various chromatographic techniques and characterized by NMR and GC/MS methods. The isolated compounds inhibited lipid peroxidation (by 85%) at 100 ppm when compared to 89%, 87%, and 98% for the commercial antioxidants butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), and tert-butylhydroxyquinone (TBHQ) at 1.67, 2.2, and 1.67 ppm, respectively. Although not selective, some of these compounds inhibited cyclooxygenase (COX)-1 and -2 enzymes. Compounds 36 were isolated for the first time from A. canadensis and compounds 710 were isolated for the first time from A. arborea fruits.  相似文献   

13.
Five previously uncharacterised polyphenols, ethyl gallate (2), 1-β-O-galloyl-d-glucopyranose (3), methyl brevifolin carboxylate (4), brevifolin (5) and 4-O-α-l-rhamnopyranosyl-ellagic acid (8), and three previously identified polyphenols, gallic acid (1), corilagin (6) and ellagic acid (7), were isolated from longan seeds. Their structures were identified by spectroscopic and chemical methods including HRESIMS and NMR. Eight polyphenols exhibited scavenging activity towards DPPH radicals with SC50 values of 0.80–5.91 μg/ml and towards superoxide radicals with SC50 values of 1.04–7.03 μg/ml. The radical-scavenging activity of the newly characterised polyphenols was comparable to that of gallic acid, corilagin and ellagic acid.  相似文献   

14.
Mammalian α-glucosidase inhibitory activity by Terminalia chebula Retz. fruits was investigated. The aqueous methanolic extract was found to have potent rat intestinal maltase inhibitory activity, whereas neither intestinal sucrase nor isomaltase activity was inhibited by this extract. Using bioassay-guided separation, three active ellagitannins were identified as chebulanin (1), chebulagic acid (2) and chebulinic acid (3) and were shown to possess potent intestinal maltase inhibitory activity, with the IC50 values of 690 μM, 97 μM and 36 μM, respectively. The intestinal maltase inhibitory activities of 2 and 3 were even higher than that of 1,2,3,4,6-penta-O-galloyl-β-d-glucose (PGG) (4, IC50=140 μM), which is a known potent α-glucosidase inhibitor. Comparison of the activities of 14, 1,2,3-O-trigalloyl-β-d-glucose (5), neochebulagic acid (6) and corilagin (7) suggested that the positions of chebulloyl and galloyl groups mostly affected the potency. Kinetic studies revealed that 2, 3, and 4 inhibited maltose-hydrolyzing activity of intestinal α-glucosidase, noncompetitively. This is the first report on mammalian α-glucosidase inhibition by 1, 2 and 3 isolated from T. chebula fruits. These results suggest a use of the extract of T. chebula fruits for managing Type 2 diabetes.  相似文献   

15.
The flavonoids composition of kumquat (Fortunella japonica) crude juice, obtained from uripe and ripe fruits, were investigated by reverse-phase LC-DAD-ESI-ITMS analysis. Thirteen compounds (C- and O-glycosyl flavonoids) were identified. Acacetin 3,6-di-C-glucoside (1), vicenin-2 (2), lucenin-2 4′-methyl ether (3) narirutin 4′-O-glucoside (4) and apigenin 8-C-neohesperidoside (5) were identified for the first time in kumquat juice. Furthermore, we report on the remarkable antioxidant properties of crude juice, of selected flavonoids fractions and of the main component, phloretin 3′,5′-di-C-glucoside (6).  相似文献   

16.
In order to evaluate the flavonoid level variation in an onion (Allium cepa L.) infected by Fusarium oxysporum, the bulbs of a healthy onion and of an infected one were analysed for flavonoids via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). Among eleven flavonoids characterised, isorhamnetin 4′-O-galactoside (8) was identified in an onion for the first time. When the healthy bulb was inoculated with the fungus, the two quercetin derivatives (4 and 7) and the two isorhamnetin derivatives (5 and 9) underwent concentration changes typical for the defense materials against pathogens. The yellow granules that were accumulated on the abaxial epidermal cell layers after 8 days of inoculation were confirmed as quercetin (10) and isorhamnetin (11). It was deduced that they were produced from flavonoids 4, 5, 7 and 9 by hydrolysis enzyme of the fungus.  相似文献   

17.
The aim of this study was to isolate and identify the anthocyanins in the black seed coated soybean (cv. Cheongja 3, Glycine max (L.) Merr.) using reverse phase C-18 open column chromatography and high-performance liquid chromatography (HPLC) with diode array detection and electro spray ionization/mass spectrometry (DAD-ESI/MS) analysis, respectively. Anthocyanins were extracted from the coat of black soybeans with 1% TFA in methanol, isolated by RP-C-18 column chromatography, and their structures elucidated by 1D and 2D NMR spectroscopy. The isolated anthocyanins were characterised as delphinidin-3-O-glucoside (3), cyanidin-3-O-glucoside (5), petunidin-3-O-glucoside (6), pelargonidin-3-O-glucoside (7) and cyanidin (9). Furthermore, four minor anthocyanins were detected and identified as catechin-cyanidin-3-O-glucoside (1), delphinidin-3-O-galactoside (2), cyanidin-3-O-galactoside (4), and peonidin-3-O-glucoside (8) based on the fragmentation patterns of HPLC-DAD-ESI/MS analysis.  相似文献   

18.
Three new flavonol glycosides, 3′,5′ dimethoxymyricetin-4″-O-α-l-rhamnopyranosyl (1–4) β-d-glucopyranoside (1), 3′-methoxyquercetin-4″-O-α-l-rhamnopyranosyl (1–4) β-d-glucopyranoside (2) and 3′-methoxyqurecetin-6″-O-α-l-rhamnopyranosyl (1–6) β-d-glucopyranoside (3), have been isolated from the aerial part of Barbeya oleoides Schweinf., along with twelve known compounds, uvaol (4), ursolic acid (5), corosolic acid (6), arjunolic acid (7), β-sitosterol-3-O-β-d-glucoside (8), (+)–catechin (9), (-)-epicatechin (10), isorhamnetin-4′-O-glucoside (11), arjunglucoside I (12), d-(-)-bornesitol (13), gallocatechin (14) and epigallocatechin (15). Compounds 415 were isolated for the first time from Barbeyaceae. Structure elucidation of compounds 1–3 was based on MS and NMR data. The ethyl acetate extract of the stems as well as compounds 5, 6, 14 and 15 showed significant antimicrobial activity, while the ethanol extracts of leaves, stems and compounds 4, 7, 8, 13–15 have dose-dependent spasmolytic action.  相似文献   

19.
Orostachys japonicus cultivated in the Republic of Korea was analysed for flavonoid content via HPLC coupled to MS/MS. Amongst 16 compounds that were characterised, eight flavonoids and one alkaloid were characterised for the first time: two procyanidin dimer gallate isomers (1 and 2), epigallochatechin-3-gallate (3), two procyanidin dimer digallate isomers (4 and 9), quercetin 3-O-rhamnosyl-7-O-glucoside (6), myricetin 3-O-glucoside (10), kaempferol (16) and N1,N5,N10-tri-p-(E,E,E)-coumaroylspermidine (15). The identified compounds were quantified by HPLC–UV/DAD. The antioxidant activity of the O. japonicus flavonoids was determined via 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS•+) and nitric oxide radical (NO) scavenging assays.  相似文献   

20.
Two novel highly oxygenated nortriterpenoids, schisarisanlactones A (1) and B (2), have been isolated from the fruits of Schisandra arisanensis, an endemic plant of Taiwan. Compounds 1 and 2 possess an unprecedented 5/5/7/5/5-fused pentacyclic ring system. The structures of both compounds were determined on the basis of spectroscopic analyses, especially 2D NMR and MS. A plausible biogenetic pathway of 1 was proposed. Schisarisanlactone A (1) showed significant anti-HIV activity.  相似文献   

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