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1.
The volatiles of five samples of Greek propolis from various geographic origin (A–E) were analyzed by capillary gas chromatography, using flame ionization GC and mass spectrometric detection. Ninety-four components were identified from the oils. The major components from each sample were found to be: junipene (11.7%), α-pinene (7.9%), manoyl oxide (7.1%) (sample A), α-pinene (45.8%), trans-β-terpineol (6.6%) (sample B), α-pinene (17.7%), α-eudesmol (12.1%), n-decanal (6.2%), guaiol (5.0%) (sample C), α-pinene (18.2%), δ-cadinene (8.4%) and α-muurolene (5.0%) (sample D), α-pinene (10.9%), n-decanal (10.3%), cedrol (6.3%), n-nonanal (5.4%), and manool (5.2%) (sample E). The total profile of the volatile constituents of all samples reveals the predominance of terpenoids, especially of α-pinene. The in vitro antimicrobial activity of the volatiles from all five studied samples against six bacteria and three fungi is also assayed and reported.  相似文献   

2.
Propolis is a resinous natural hive product derived from plant exudates collected by honeybees. Due to biological and pharmacological activities, it has been extensively used in folk medicine. The present study was designed to investigate the chemical composition, subchronic toxicity, antimicrobial activity of Iranian propolis ethanolic extract, which has not been studied previously. One hundred and nine compounds were identified by gas chromatography–mass spectrometry analysis. Forty-five days subchronic toxicity of oral propolis extract was investigated in male rats. During the study no significant behavioral and clinical toxicity has been seen in animals however, hematologic, blood biochemistry and histopathologic data studies exhibited some significant differences between the groups. The ethanolic extract of propolis inhibited the growth of all examined microorganisms including bacteria and fungi with the highest antimicrobial activity against Gram-positive bacteria such as Staphylococcus aureus and Staphylococcus epidermidis.  相似文献   

3.
Antioxidant activities of ethanol and petroleum ether extracts from Brazilian propolis were determined by α,α-diphenyl-β-picrylhydrazyl (DPPH) radical-scavenging and ferric thiocyanate (FTC) methods, using α-tocopherol and butylated hydroxytoluene (BHT) as references. The DPPH assay showed that ethanol extract possessed significantly higher activity compared with BHT and petroleum ether extract but lower than that of α-tocopherol. Results from the FTC assay indicated that the activity of ethanol extract was higher than that of α-tocopherol and petroleum ether extract but lower than BHT. Basically, this antioxidant activity was dose-dependent and ethanol extract exhibited higher activity than that of petroleum ether extract at the same concentration. Additionally, the chemical constituents of propolis were determined, and results showed that the propolis contained high content of antioxidant compositions, such as flavonoids (73.00 g kg−1), total phenolic compounds (134.40 g kg−1), and Vitamin E (0.16 g kg−1), which contributed greatly to its strong antioxidant activity.  相似文献   

4.
Y.M. Choi  S.Y. Cho  K.M. Kim  J.M. Kim 《LWT》2006,39(7):756-761
Biological activities of different propolis extracts in Korea were examined for the evaluation of quality comparison with that from Brazil (BZ). Total polyphenol and flavonoid contents of propolis extracts from Yeosu (YS) and Cheorwon (CW), whose values were higher than BZ, were also shown to be more aboudant. The extracts of YS and CW also showed strong antioxidant activities, using the linoleic acid peroxidation and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. However, the extract from BZ had less active antioxidant activity on linoleic acid peroxidation and DPPH free radical-scavenging activity of less than 70% than other extracts. The DPPH free radical-scavenging activity seems to relate with the antioxidant activity of linoleic acid peroxidation. The propolis with antioxidant activity also had DPPH free radical-scavenging activity. The extracts of YS and CW had effective antimicrobial activities on Staphilococcus aureus, Bacillus subtilis, Salmonella typhimurium and Candida albicans. Strong antioxidant, radical-scavenging and antimicrobial activities of YS and CW seemed to relate with high values, total polyphenol, and flavonoid contents.  相似文献   

5.
Propolis, an extremely complex resinous material gathered by honeybees from various plant sources, exhibits valuable pharmacological and biological properties attributed to the presence of polyphenols. This study examined the antibacterial, antiradical and antioxidant activities of propolis from different provenances and correlated the values with total levels of polyphenolic compounds and flavonoids. Besides, individual contents of those polyphenols with antioxidant ability were determined and related with their bioactivity. Analyzed samples presented a noticeable variability in their antioxidant and antiradical activities, although, linear relationships were found between them and also between polyphenol and flavonoid total levels. Propolis antiradical and protective abilities against lipid oxidation are related to its high levels of polyphenols, but their correlations with individual active-compound contents were not simple. Antibacterial activity against Staphylococcus aureus of the samples presented low variability. This bioactivity is assigned to pinocembrin, present in high concentrations in all the samples studied. Good correlation was found between such activity and pinocembrin content. Linear relationships between antibacterial activity and polyphenol and flavonoid total levels were also found.  相似文献   

6.
The present study was aimed at identification of antifungal components against Penicillium italicum from Chinese propolis with bioassay-guided fractionation technique. Propolis ethanolic extract (PEE) was separated and purified by liquid–liquid extraction and thin layer chromatography (TLC) and the most active band was subjected to HPLC–MS/MS to identify the antifungal compounds. The results showed PEE and its fractions had strong antifungal activity against P. italicum. Among the fractions of PEE partitioned by petroleum ether, ethyl acetate, n-butanol and water, ethyl acetate fraction (E-Fr) exhibited the most effective activity against P. italicum. Further bioautographic TLC assay showed Band I, with Rf value of 0.70, had an inhibitive zone, which showed the strongest antifungal activity and completely inhibited the growth of P.italicum at 200 mg/L. Bioactive components found in Band I were further identified as pinobanksin, pinocembrine, chrysin and galangin. This study exhibited Chinese propolis and its main flavonoids was potential natural alternatives for the control of citrus blue mould caused by P.italicum.  相似文献   

7.
分子蒸馏法制备鱼油多不饱和脂肪酸   总被引:1,自引:0,他引:1       下载免费PDF全文
研究了多级分子蒸馏法提取深海鱼油中多不饱和脂肪酸的工艺方法,通过对压力和温度的控制得到不同多不饱和脂肪酸含量的各级鱼油产品,当蒸馏温度为110℃以上,蒸馏压力为20Pa以下时,经过三级串联分子蒸馏,得到高碳链不饱和脂肪酸质量分数为90.96%的鱼油产品,并用气相色谱法测定了产品的脂肪酸组成,分析了产品的理化指标.  相似文献   

8.
Proximate composition, fatty acid and amino acid analysis of an echinoderm (Paracentrotus lividus), a crustacean (Penaeus kerathurus), a tunicate (Microcosmus sulcatus), and two gastropod molluscs (Littorina littorea and Patella coerulea) were determined. All organisms except M. sulcatus, were found to be good protein sources. P. lividus contained on average 15.1 g/100 g, P. kerathurus 15.6 g/100 g, L. littorea 8.3 g/100 g and P. coerulea 9.2 g/100 g protein. The crustacean contained high percentages of n‐3 fatty acids (28.3 g/100 g fatty acids), the tunicate high percentages of saturated fatty acids (62.2 g/100 g fatty acids) while the gastropod molluscs and the echinoderm had a balanced content of all fatty acid families. The most abundant amino acid in P. kerathurus, M. sulcatus, L. littorea and P. coerulea was glutamic acid (11.13 ± 0.9, 1.05 ± 0.3, 5.39 ± 0.3, 5.55 ± 0.8 g/100 g freeze‐dried sample respectively), while glycine was the most abundant amino acid in P. lividus (10.34 ± 1.0 g/100g freeze‐dried sample).  相似文献   

9.
通过实验研究表明:巴旦杏仁乳饮料品质改良的关键在于护色和防止脂肪上浮及蛋白质颗粒下沉,针对上述问题选择适当的脱皮剂,乳化剂及调节乳液的pH值,得到巴旦杏仁去皮最佳条件为:0.1%氢氧化钠沸腾溶液中浸泡5 min;复合乳化稳定剂的最佳用量组合为:WGMS:WPGE:WSE11:WBE-2=0.1:0.2:0.1:0.1.  相似文献   

10.
Marianna Gulfi  Renato Amadò 《LWT》2006,39(9):1001-1004
The aim of the present study was to characterize the fermentability of different apple pectins, as soluble dietary fibres, in vitro. High- and low-methoxyl pectins were fermented completely and very fast by human colonic bacteria, whereas pectic acid and amidated pectin were degraded more slowly. The main fermentation metabolites, i.e. short-chain fatty acids (SCFA) and gases, were produced in lower amounts from pectic acid and amidated pectin. Based on the higher production of SCFA, pectins with a higher degree of methoxylation might be the best candidates for food enrichment due to a beneficial effect on colonic health. On the other hand, the longer persistence of the slowly degraded pectins in the gut may be of advantage as binding and diluting agents for carcinogens.  相似文献   

11.
《Journal of dairy science》2023,106(4):2395-2407
The form of a lipid supplement, its degree of saturation, and its fatty acid (FA) profile greatly influence digestibility and cow productive response. The objective in this study was to examine the effect of fat supplements that differ in their form or FA profile on nutrient digestibility and cow performance. Forty-two mid-lactation cows (128 ± 53 d) were assigned to 3 treatment groups according to milk yield, days in milk, and body weight. For 13 wk, the cows were fed rations that contained (on a dry matter basis) (1) 2.4% of calcium salts of fatty acids (CSFA) consisting of 45% palmitic acid (PA) and 35% oleic acid (OA; CS45:35); (2) 2.4% of CSFA consisting of 80% PA and 10% OA (CS80:10); or (3) 2.0% of free FA consisting of 80% PA and 10% OA (FF80:10). Rumen samples were taken to measure the ammonia and volatile FA concentrations, and fecal samples were taken to measure the digestibility. Preplanned comparisons were CS45:35 versus CS80:10 to assess 2 CSFA supplements with different FA profiles, and CS80:10 versus FF80:10 to assess similar FA profiles in different forms. Compared with CS45:35, CS80:10 decreased the milk yields, increased the fat percentage, and tended to increase the energy-corrected milk (ECM) yields. The fat percentage of milk was highest in the FF80:10 cows (4.02%), intermediate in the CS80:10 cows (3.89%), and lowest in the CS45:35 cows (3.75%). Compared with CS80:10, FF80:10 increased milk yields (50.1 vs. 49.4 kg/d, respectively), tended to increase fat percentage, and increased 4% fat-corrected milk (4% FCM; 49.1 vs. 47.7 kg/d, respectively) and ECM yields (49.5 vs. 48.2 kg/d, respectively). Treatment had no effect on dry matter intake (DMI), and compared with CS80:10 cows, the calculated energy balance was lower in the FF80:10 cows. The 4% FCM/DMI and ECM/DMI ratios were higher in the FF80:10 group compared with the CS80:10 group. Compared with the CS80:10 cows, the FF80:10 cows had a lower rumen pH, higher propionate, lower acetate/propionate ratio, and higher total VFA. Compared with CS45:35 cows, the apparent total-tract digestibilities of neutral detergent fiber and acid detergent fiber were higher in CS80:10 cows; whereas, the apparent total-tract digestibilities of dry matter, organic matter, protein, neutral detergent fiber, and acid detergent fiber were higher in the CS80:10 cows compared with the FF80:10 cows. Compared with the CS80:10 group, the apparent digestibility of total FA was 13.0 percentage points lower in the FF80:10 cows (79.1 vs. 66.1%, respectively), and similarly, the digestibilities of 16-carbon and 18-carbon FA were lower in the FF80:10 cows than in the CS80:10 cows. In conclusion, the form, more than the FA profile of fat supplements, influenced digestibility. Further, the CSFA supplements were more digestible than the free fatty acids, regardless of the FA profile. However, energy partitioning toward production appeared to be higher in the FF80:10 cows, although the digestibility of nutrients was lower than in the CSFA product with a similar FA profile.  相似文献   

12.
BACKGROUND: The effect of breed and whole sunflower seed on performance, carcass traits and the composition of meat was evaluated in Charolais (CH) and Simmental (SI) bulls. Samples of musculus longissimus lumborum (MLL) and musculus infraspinatus (MIS) were analysed. RESULTS: The CH bulls had a lower feed intake per kg of gain, a higher killing‐out percentage and produced more valuable carcasses. The muscles from SI bulls contained more monounsaturated fatty acids (FA) and less saturated FA (in g kg?1 FA) than the muscles from CH bulls. The sunflower seed supplement increased the proportions of linoleic acid and c9t11 conjugated linoleic acid and the ratio of polyunsaturated fatty acids (PUFA) to saturated FA and decreased the index of atherogenicity of FA in meat lipids. CONCLUSION: The results of this study demonstrated the superiority of the CH over the SI breed in a number of economically important traits. The breed effect on the nutritional quality of meat was ambiguous. Meat lipids of the SI bulls contained more unsaturated FA but also more PUFA n‐6 and a higher PUFA n‐6/PUFA n‐3 ratio. Copyright © 2008 Society of Chemical Industry  相似文献   

13.
The aim of this study was to determine the influence of apple variety (Šampion, Idared and Gloster) on the polyphenol profile, volatile composition and sensory characteristics of apple wines. Apples were harvested from the orchard in Garlica Murowana (Poland) and the experiments were conducted on a laboratory scale. Statistically significant differences were detected in the chemical composition of the analyzed wines. The highest antioxidant activity was found in Šampion wines, which was associated with a relatively high concentration of chlorogenic acid and procyanidins. These samples also contained high amounts of acetaldehyde, ethyl acetate and methanol. Idared wines showed a similar polyphenol profile, but they had lower antioxidant capacity and were characterized by a high level of butanol and acetic acid. Gloster wines were distinguished from other samples by a lower concentration of polyphenols and higher concentration of fusel alcohols. During sensory evaluation, wines produced from Idared apples scored the highest value for overall quality.  相似文献   

14.
The effects of seasonal variations on the proximate chemical compositions and fatty acid profiles of chub mackerel (Scomber japonicus) and horse mackerel (Trachurus trachurus) captured in the north‐eastern Mediterranean Sea were investigated. Protein fluctuations were observed in two species for all seasons. The lipid content of both species was lower in winter than in autumn and spring. In all seasons, the major fatty acids in both species were observed to be palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1 ω9), eicosapentaenoic acid (20:5 ω3) and docosahexaenoic acid (20:6 ω3). Chub mackerel and horse mackerel exhibited seasonal fluctuations in their fatty acid contents. The fatty acid profile of the two species had a higher degree of unsaturation during winter. The levels of EPA in chub mackerel in winter, spring and autumn were 5.96%, 4.86% and 4.33%, respectively, while those of DHA were 24.94%, 18.75% and 17.12%, respectively. The levels of EPA in horse mackerel in winter, spring and autumn were 5.42%, 5.03% and 4.86%, respectively, while those of DHA were 14.96%, 13.31% and 11.10%, respectively. The PUFA (polyunsaturated fatty acids) values and ω3/ω6 ratios in the two species were highest in winter. The results indicate that chub mackerel and horse mackerel captured in the north‐eastern Mediterranean Sea, which are among the most important fish in Turkey and of international commercial value, are a good source of nutrition for human consumption in terms of their proximate chemical composition and fatty acids.  相似文献   

15.
本文以水解度为指标,采用胰蛋白酶、酸性蛋白酶、木瓜蛋白酶、风味蛋白酶、中性蛋白酶对鲐鱼鱼肉和下脚料最佳用酶进行筛选和优化,测定酶解液的氨基酸组成和抗氧化活性。结果表明:风味蛋白酶为最佳用酶;优化条件为:鱼肉:加酶量1200 U/g,物料比1:15,pH值5.5,48℃酶解6.5 h,水解度为37.8%;下脚料:加酶量1200 U/g,物料比1:8,pH值6.0,48℃酶解6.5 h,水解度为37.1%。两者酶解液的抗氧化活性表明,羟自由基的EC50值分别为0.58mg/mL和0.28 mg/mL,均具有较强的还原能力,酶解液经喷雾干燥得黄色粉末,氨基酸种类齐全,必需氨基酸含量为38.53%和43.17%。本实验为鲐鱼的开发利用提供了理论依据。  相似文献   

16.
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18.
The chemical composition of essential oils of six Stachys species, S. cretica L. ssp. vacillans Rech. fil., S. germanica L., S. hydrophila Boiss., S. nivea Labill., S. palustris L. and S. spinosa L., obtained by hydrodistillation, was studied by GC and GC–MS. All the oils have in common a great percentage of fatty acids and esters (24.2–58.5%) and a high amount of sesquiterpenes (16–35.9%), with the exception of the oil from S. palustris, which consisted mainly of carbonylic compounds (25.4%). The antioxidant activity by DPPH test and the antiproliferative activity on a series of human cancer cell lines (C32, amelanotic melanoma and ACHN, renal cell adenocarcinoma) were investigated for all the oils. S. palustris,S. cretica and S. hydrophila showed the highest antiradical effect, with IC50 values of 0.482, 0.652 and 0.664 mg/ml, respectively. The most antiproliferative essential oil against C32 cell line was the oil of S. germanica with a 77% of inhibition at a concentration of 100 μg/ml. S. germanica, S. palustris and S. spinosa showed the most antiproliferative activity on ACHN cell line, at a concentration of 100 μg/ml,with 81%, 77% and 73% inhibition, respectively.  相似文献   

19.
The influence of breed and mh-genotype on carcass conformation, meat physico-chemical characteristics and the fatty acid profile of muscle were studied. Samples from 16 yearling bulls from “Asturiana de los Valles” (AV, n = 12) and “Asturiana de la Montaña” (AM, n = 4) were collected. AV animals were classified into three groups according to the presence of the gene causing double-muscling (AV double-muscled (mh/mh), n = 4; AV heterozygous (mh/+), n = 4; AV normal (+/+), n = 4). Double-muscled animals displayed better carcass traits, lower total fat (comprised of subcutaneous (SC), intermuscular (IT) and intramuscular (IM) deposits), higher lean, moisture and drip loss, and lighter meat than AV normal animals. Heterozygous animals showed intermediate characteristics. AM animals, being a more rustic and smaller breed, showed lower conformation, higher total fat (SC, IT and IM), lower moisture and darker meat. According to the intramuscular fatty acid profile, mh/mh animals showed a lower proportion of SFA and MUFA, and a higher proportion of PUFA with an equal proportion of CLA in total fatty acid content. The P/S ratio increased with increasing number of mh alleles (or double-muscling character), while no differences between animal groups were found for the n − 6/n − 3 ratio.  相似文献   

20.
鲢鱼露发酵工艺的研究   总被引:3,自引:0,他引:3  
以发酵温度 35℃、4 0℃和 4 5℃ ,加曲量 4 0 %、2 0 %和 10 % ,加盐量 10 %、14%和18%作为L9(34)正交试验的因素与水平 ,考察其对鱼露氨基酸生成率及鱼露综合质量的影响。结果表明 ,温度对氨基酸生成率有一定影响 ,对鱼露综合质量的影响极显著 ;加盐量对氨基酸生成率有显著影响 ,对鱼露综合质量有极显著影响 ,随着加盐量减少 ,氨基酸生成率和鱼露综合质量都明显增加 ;当加曲量达到 10 %后再增大加曲量 ,对氨基酸生成率及鱼露综合质量的影响都不显著。氨基酸生成率最高的工艺条件为温度 35℃、加盐量 10 %、加曲量为10 %~ 4 0 % ;鱼露综合质量最好的工艺条件为温度 4 5℃、加盐量 10 %、加曲量为 10 %~4 0 % ;最后 ,确定鱼露的速酿最佳工艺条件为温度 4 5℃、加盐量 10 %、加曲量为 4 0 %  相似文献   

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