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1.
In this study, we show that 5α‐reductase derived from rat fresh liver was inhibited by certain aliphatic free fatty acids. The influences of chain length, unsaturation, oxidation, and esterification on the potency to inhibit 5α‐reductase activity were studied. Among the fatty acids we tested, inhibitory saturated fatty acids had C12–C16 chains, and the presence of a C?C bond enhanced the inhibitory activity. Esterification and hydroxy compounds were totally inactive. Finally, we tested the prostate cancer cell proliferation effect of free fatty acids. In keeping with the results of the 5α‐reductase assay, saturated fatty acids with a C12 chain (lauric acid) and unsaturated fatty acids (oleic acid and α‐linolenic acid) showed a proliferation inhibitory effect on lymph‐node carcinoma of the prostate (LNCaP) cells. At the same time, the testosterone‐induced prostate‐specific antigen (PSA) mRNA expression was down‐regulated. These results suggested that fatty acids with 5α‐reductase inhibitory activity block the conversion of testosterone to 5α‐dihydrotestosterone (DHT) and then inhibit the proliferation of prostate cancer cells.  相似文献   

2.
The hydrodistilled essential oils obtained from aerial flowering parts of Teucrium stocksianum ssp. stocksianum (TSS) and T. stocksianum ssp. gabrielae (TSG) from Iran were analyzed by capillary GC and GC/MS. The oil analysis of two subspecies led to the identification of 65 compounds that accounted for 93.3 and 95.1% of the total oil compositions, respectively. Sesquiterpenoids (52.9%) constituted the main compounds in the essential oil of TSS represented mainly by cis‐sesquisabinene hydrate (12.0%), followed by epiβ‐bisabolol (6.6%), guaiol (5.4%), and β‐eudesmol (4.4%), whilst monoterpenoids (61.2%) were found to be the major components of the oil of TSG, represented by α‐pinene (23.0%), β‐pinene (13.0%), myrcene (6.3%), and sabinene (6.3%). The principal component in both subspecies, TSS and TSG, was α‐pinene (22.0 and 23.0%, resp.) and β‐pinene (6.5 and 13.0%, resp.). epiα‐Cadinol, myrcene, and sabinene, which were detected as principal compounds of TSG, were characterized in lower amounts (<1.5%) in the oil of TSS. Seven components were identified in the oil of TSS corresponding to 25.9% of total oil, which were totally absent in the oil of TSG, of which cis‐sesquisabinene hydrate (12.0%), guaiol (5.4%), and β‐eudesmol (4.4%) were in considerable amounts. Taxonomic position of the subspecies is discussed on the basis of phytochemical data.  相似文献   

3.
Both enantiomers of three biologically relevant paraconic acids—MB‐3, methylenolactocin, and C75—were obtained with enantioselectivities up to 99% by kinetic enzymatic resolutions. Good enantiomeric excesses were obtained for MB‐3 and methylenolactocin, using α‐chymotrypsin and aminoacylase as enantiocomplementary enzymes, while C75 was resolved with aminoacylase. They all were evaluated for their antiproliferative, antibacterial, and antifungal activities, showing weak effects and practically no difference between enantiomers in each case. At high concentrations (16–64 µg/mL), (–)‐ C75 acted as an antimicrobial agent against Gram‐positive bacteria. Chirality 27:239–246, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

4.
In aquaculture, α-tocopheryl acetate (α-TA) is the main source of vitamin E used to fortify fish feed. α-TA in fish is often determined indirectly, i.e., by alkaline hydrolysis, followed by quantitation of “total α-tocopherol” (α-T) and subtraction of the natively present α-T. The aim of this study was to develop an HPLC method for the simultaneous quantitative determination of α-TA and free tocopherols in aquatic organisms and fish feed. The assay consists of a simple extraction with methanol containing butylhydroxytoluene (BHT) as an antioxidant, followed by reversed-phase chromatography with consecutive UV and fluorescence detection of α-TA and tocopherols, respectively. The peak of the internal standard tocol in the fluorescence trace was used for quantitation. Linearity was achieved over the range of 0.2 to 4.2 μg α-TA per ml extract of Artemia nauplii, which would correspond to 30.7 to 614.4 μg/g dry mass. The within-run coefficient of variation was 1.9% at a level of 310 μg/g dry mass. The recovery of α-TA ranged from 97.7 to 100.8% (concentration=2.1 and 20.5 μg/ml, n=6). The detection limit was about 7 ng and the quantification limit on spiked samples was 0.2 μg/ml. This method was routinely applied to determine α-TA and α-, γ- and δ-tocopherol (α-T, γ-T, δ-T) simultaneously in Artemia, fish feed, shrimp eggs and various other aquatic organisms.  相似文献   

5.

Objectives

Previous research has established population variation in anti‐inflammatory immunological biomarkers in human milk. This immunity is potentially ecology‐dependent and may alter the life history trade‐off between growth and maintenance in infants. The current study has two aims: (1) to assess the ecological differences in milk immunity in two populations, one from the urban U.S. and one from rural Kenya; and (2) to test the hypothesis that milk immunity can affect infant growth indicators.

Materials and Methods

Kenyan Ariaal (n = 233) and U.S. (n = 75) breastfeeding mother‐infant pairs participated in a cross‐sectional study at two separate field sites. Laboratory analysis was performed on milk for the anti‐inflammatory biomarkers TGF‐β2, sTNF‐αRI, sTNF‐αRII, and IL‐1ra using ELISA. Multiple imputation was used to extrapolate data below the limit of detection before multivariate analysis.

Results

There were significant differences between U.S. and Kenyan mothers on all four milk biomarkers, with Kenyan mothers having significantly higher sTNF‐αRI and sTNF‐αRII and lower TGF‐β2 and IL‐1ra than U.S. mothers. U.S. mothers with higher milk TGF‐β2 and IL‐1ra have infants that are significantly longer and heavier for their age, while Kenyan mothers with higher sTNF‐αRI have significantly longer and heavier infants for their age, and those with higher TGF‐β2 have marginally significantly longer infants.

Discussion

There were significant differences in ecological milk immunity between U.S. and Kenyan mothers. These differences potentially play a role in the growth of their infants. Further research in milk immunity should consider the possibility of shared maternal–infant life histories.
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6.
The essential oils (EOs) isolated from the leaves and twigs of Juniperus excelsa M.Bieb . growing wild in Lebanon were characterized, and their antimicrobial activity and antiradical capacity were evaluated. The EOs were obtained by hydrodistillation using a Clevenger‐type apparatus and characterized by GC and GC/MS analyses. The antimicrobial activity was evaluated by determining minimal inhibitory concentrations (MICs) against a Gram‐positive and a Gram‐negative bacterium, a yeast, and a dermatophyte with the broth microdilution technique. A total of 28 constituents was identified and accounted for 90.1 and 95.6% of the twig and leaf EO composition, respectively. Both EOs were essentially composed of monoterpene hydrocarbons (46.7 and 59.6% for twig and leaf EOs, resp.) and sesquiterpenes (39.4 and 32.1%, resp.). The main components were α‐pinene, α‐cedrol, and δ‐car‐3‐ene. The J. excelsa EOs did not show any antiradical potential, but revealed interesting in vitro antimicrobial activities against Staphylococcus aureus and Trichophyton rubrum (MICs of 64 and 128 μg/ml, resp.). The three major compounds were tested separately and in combination according to their respective amounts in the oil. δ‐Car‐3‐ene was the most active component and is undoubtedly one of the constituents driving the antifungal activity of J. excelsa essential oil, even though synergies are probably involved.  相似文献   

7.
Aromatic plants attract the attention of many researchers worldwide due to their worthy applications in agriculture, human prosperity, and the environment. Essential oil (EO) could be exploited as effective alternatives to synthetic compounds as it has several biological activities including allelopathy. The EO from the aerial parts of Rhynchosia minima was extracted by hydrodistillation and investigated by gas chromatography/mass spectrometry (GC/MS). Different concentrations (50, 100, 150 and 200 μL L−1) of the EO were prepared for investigation of their allelopathic potential on two weeds; Dactyloctenium aegyptium and Rumex dentatus. Twenty‐eight compounds, mainly sesquiterpenes (69.13%) were determined. The major compounds are α‐eudesmol, 2‐allyl‐5‐tert‐butylhydroquinone, caryophyllene oxide, trans‐caryophyllene, and τ‐cadinol. The EO from the Rminima showed a significant inhibition of Daegyptium and Rdentatus germination, while the seedling growth was stimulated. Therefore, it is not recommended to treat these noxious weeds with the EO of Rminima before the germination. In contrast, the apparent stimulatory effect on the seedling growth offers further studies to use the EO of Rminima to enhance the fitness of different economic crops. However, characterization of green bio‐herbicides such as EO (allelochemicals) from wild plants raises a new opportunity for the incorporation of new technology of bio‐control against the noxious weeds.  相似文献   

8.
The adaptation of nine species of mites that infest stored products for starch utilization was tested by (1) enzymatic analysis using feces and whole mite extracts, (2) biotests, and (3) inhibition experiments. Acarus siro, Aleuroglyphus ovatus, and Tyroborus lini were associated with the starch‐type substrates and maltose, with higher enzymatic activities observed in whole mite extracts. Lepidoglyphus destructor was associated with the same substrates but had higher activities in feces. Dermatophagoides farinae, Chortoglyphus arcuatus, and Caloglyphus redickorzevi were associated with sucrose. Tyrophagus putrescentiae and Carpoglyphus lactis had low or intermediate enzymatic activity on the tested substrates. Biotests on starch additive diets showed accelerated growth of species associated with the starch‐type substrates. The inhibitor acarbose suppressed starch hydrolysis and growth of the mites. We suggest that the species with higher starch hydrolytic activity in feces were more tolerant to acarbose, and α‐amylase and α‐glucosidase of synanthropic mites are suitable targets for inhibitor‐based strategies of mite control. © 2009 Wiley Periodicals, Inc.  相似文献   

9.
10.
Abies nebrodensis (Lojac .) Mattei (Pinaceae) is a species occurring in a very small population only in a restricted area of Sicily. Its taxonomic classification as different species has been object of discussion. In this work the chemical composition of the essential oil from the leaves is presented for the first time and compared to the essential oils from other euroasiatic species reported in literature. Peculiar characteristics of the essential oil of A. nebrodensis are highlighted.  相似文献   

11.
α, ω‐Dodecanedioic acid (DC12) usually serves as a monomer of polyamides or some special nylons. During the biosynthesis, oxygenation cascaded in conversion of hydrophobic n‐dodecane to DC12, while the oxidation of n‐dodecane took place in the intracellular space. Therefore, it was important to investigate the role of oxygen supply on the cell growth and DC12 biosynthesis. It was found that stirring speed and aeration influenced the dissolved oxygen (DO) concentration which in turn affected cell growth as well as DC12 biosynthesis. However, the effect of culture redox potential (Orp) level on DC12 biosynthesis was more significant than that of DO level. For DC12 biosynthesis, the first step was to form the emulsion droplets through the interaction of n‐dodecane and the cell. When the stirring speed was enhanced, slits in the surface layer of the emulsion droplets would be increased. Thus, the substances transportation by water through the slits would be intensified, leading to an enhanced DC12 production. Compared with the batch culture at a lower stirring speed (400 rpm) without culture redox potential (Orp) control, the DC12 concentration was increased by 5 times up to 201.3 g/L with Orp controlled above 0 mV at a higher stirring speed (800 rpm).  相似文献   

12.
Inflammatory cytokines are closely related to pigmentary changes. In this study, the effects of IFN‐γ on melanogenesis were investigated. IFN‐γ inhibits basal and α‐MSH‐induced melanogenesis in B16 melanoma cells and normal human melanocytes. MITF mRNA and protein expressions were significantly inhibited in response to IFN‐γ. IFN‐γ inhibited CREB binding to the MITF promoter but did not affect CREB phosphorylation. Instead, IFN‐γ inhibited the association of CBP and CREB through the increased association between CREB binding protein (CBP) and STAT1. These findings suggest that IFN‐γ inhibits both basal and α‐MSH‐induced melanogenesis by inhibiting MITF expression. The inhibitory action of IFN‐γ in α‐MSH‐induced melanogenesis is likely to be associated with the sequestration of CBP via the association between CBP and STAT1. These data suggest that IFN‐γ plays a role in controlling inflammation‐ or UV‐induced pigmentary changes.  相似文献   

13.
The chemical composition of 45 essential oil samples isolated from the leaves of Polyalthia oliveri harvested in three Ivoirian forests was investigated by GC‐FID (retention indices measured on two columns of different polarities), and by 13C‐NMR, following a method developed in our laboratory. In total, 41 components were identified. The content of the main components varied drastically from sample to sample: (E)‐β‐caryophyllene (1.2 – 50.8%), α‐humulene (0.6 – 47.7%), isoguaiene (0 – 27.9%), alloaromadendrene (0 – 24.7%), germacrene B (0 – 18.3%), δ‐cadinene (0.4 – 19.3%), and β‐selinene (0.2 – 18.5%). The analysis of six oil samples selected in function of their chromatographic profiles is reported in detail. The 45 oil compositions were submitted to hierarchical cluster and principal components analysis, which allowed the distinction of three groups within the oil samples. The compositions of the oils from group I (15 samples) and II (12 samples) were dominated by (E)‐β‐caryophyllene and α‐humulene, respectively. Oil samples of group III (18 samples) needed to be partitioned into four subgroups III.1–III.4 whose compositions were dominated by alloaromadenrene, isoguaiene, germacrene B, and δ‐cadinene, respectively.  相似文献   

14.
α‐Glycosidase is a catalytic enzyme and it destroys the complex carbohydrates into simple absorbable sugar units. The natural phenolic compounds were tested for their antidiabetic properties as α‐glycosidase and α‐amylase inhibitors. The phenolic compounds investigated in this study have been used as antidiabetic common medicines. This paper aimed to consider their capability to inhibit α‐amylase and α‐glycosidase, two significant enzymes defined in serum glucose adjustment. These examination recorded impressive inhibition profiles with IC50 values in the range of 137.36–737.23 nM against α‐amylase and 29.01–157.96 nM against α‐glycosidase.  相似文献   

15.
16.
Tannin acylhydrolase (EC 3.1.1.20) referred commonly as tannase catalyzes the hydrolysis of the galloyl ester bond of tannins to release gallic acid. Although the enzyme is useful for various industries, the tertiary structure is not yet determined. In this study, we determined the crystal structure of tannase produced by Lactobacillus plantarum. The tannase structure belongs to a member of α/β‐hydrolase superfamily with an additional “lid” domain. A glycerol molecule derived from cryoprotectant solution was accommodated into the tannase active site. The binding manner of glycerol to tannase seems to be similar to that of the galloyl moiety in the substrate. Proteins 2013; 81:2052–2058. © 2013 Wiley Periodicals, Inc.  相似文献   

17.
1IntroductionOilseedrape(BrassicanapusL.)isthemostimportantsourceofedibleoil,andtheYangtzeRiverlowerbasinisthemaincultivationregioninChina.Duringlastdecade,winterrapeproduc-tionisincreasinginthecereal-growingregionsafterthericeharvest(Zhou,1994).Weathervari-ablessuchassolarradiation,temperature,precipitation,windandhumidityhavepronouncedef-fectsonrapegrowth,developmentandseedyield(Almondetal.1986).itisprobablethatahigh-ertemperatureduringvegetativegrowththanatmainfloweringandseedfillingprod…  相似文献   

18.
1. Agricultural intensification has caused dramatic biodiversity loss in many agricultural landscapes over the last century. Here, we investigated whether new types of farm ponds (made of artificial substrata) in intensive systems and natural‐substratum ponds in traditional farming systems differ in their value for aquatic biodiversity conservation. 2. We analysed the main patterns of environmental variation, compared α‐, β‐ and γ‐diversity of macroinvertebrates between ponds types and evaluated the role of submerged aquatic vegetation (SAV). Generalised additive models (GAM) were used to analyse the relationships of α‐ and β‐diversity with environmental predictors, and variation partitioning to separate the effect of environmental and spatial characteristics on the variation in macroinvertebrate assemblages. Moran’s eigenvector maps (MEMs) were used to define spatial variables. 3. A principal coordinate analysis (PCoA) detected a primary environmental gradient that separated nutrient‐rich ponds from those dominated by SAV; a secondary morphometric gradient distinguished natural‐substratum ponds, with large surface area and structural complexity, from artificial‐substratum ponds with steeper slopes. Natural‐substratum ponds had almost twice the α‐ and γ‐diversity of artificial‐substratum ponds, and diversity significantly increased when SAV was present, particularly in artificial‐substratum ponds. Total phosphorus (TP) strongly contributed to explain the patterns in diversity, while SAV was a significant predictor of assemblage composition and diversity. GAMs revealed optima of both α‐diversity at intermediate SAV covers and β‐diversity at intermediate–high TP concentrations. 4. These findings have important implications for conservation planning. Adaptation of artificial‐substratum ponds by adding natural substratum and smoothing the gradient of pond margins would improve their conservation value. Development of SAV with occasional harvests and certain cautionary measures to control nutrient levels may also improve both the agronomical and environmental function of ponds.  相似文献   

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