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121.
In search for an alternative for nutritional antimicrobials in piglet feeding, the effects of adding whole Cuphea seeds, as a natural source of medium chain fatty acids (MCFA), with known antimicrobial effects, and an exogenous lipase to a weaner diet were studied. The foregut flora, the gut morphology, some digestive parameters and the zootechnical performance of weaned piglets were investigated. Thirty newly weaned piglets, initial weight 7.0 ± 0.4 kg, were divided according to litter, sex and weight in two groups (control diet; Cuphea+lipase diet). The Cuphea seeds (lanceolata and ignea) (50 g kg?1) were substituted for soybean oil (15 g kg?1), Alphacell (25 g kg?1) and soy protein isolate (10 g kg?1) in the control diet. Also 500 mg kg?1 microbial lipase was added to the Cuphea diet. The piglets were weighted individually on days 0, 3, 7, 14 and 16. Feed intake was recorded per pen during days 0 to 3, 3 to 7, 7 to 14 and 14 to 16. On day 7 five piglets of each experimental group were euthanized for counting the gastric and small intestinal gut flora and for gut morphology at two sites of the small intestine (proximal, distal). The results indicate a trend towards improved performances parameters by feeding Cuphea + lipase. The enzymic released MCFA (1.7 g kg?1 fresh gastric contents) tended to decrease the number of Coliforms in the proximal small intestine, but increased the number in the stomach and distal small intestine. With Cuphea, the number of Streptococci was significantly lower in small intestine, but not in the stomach, while the number of Lactobacilli was significantly lower in the distal small intestine and tended to be lower in the stomach and proximal small intestine. No differences between the diets were noted for the total anaerobic microbial load in the stomach or in the gut. Feeding Cuphea+lipase resulted in a significantly greater villus height (distal small intestine) and a lesser crypt depth (proximal and distal small intestine) and greater villus/crypt ratio depth (proximal and distal small intestine). The intra-epithelial lymphocyte (IEL) counts per 100 enterocytes were significantly decreased in the proximal small intestine and tended to decrease in the distal small intestine by feeding the Cuphea+lipase diet. Both phenomena are indicative for a more healthy and better functional state of the mucosa. Present results are in line with foregoing research, showing that manipulation of the gut ecosystem by the enzymic in situ released MCFA in the stomach and foregut can result in improved performances of the piglets, which makes the concept a potential alternative for in-feed nutritional antibiotics.  相似文献   
122.
A cinnamic imidate, (1Z,2E)-methyl 3-(-p-hydroxy-m-methoxyphenyl)-N-(-p-hydroxyphenethyl) acrylimidate, named persicoimidate (1), has been isolated and characterized from bulbs and seeds of Persian leek, Allium ampeloprasum Subsp. Persicum. Two cinnamic acid derivatives, N-feruloyl tyramine (2) and N-caffeoyl tyramine (3) were isolated from bulbs and seeds. Compound 2 has been previously reported from garlic and leek, while compound 3 is described in Allium plants for the first time. The chemical structures of the isolated compounds have been elucidated unambiguously by spectroscopic methods, including 2D NMR and MS. The isolated compounds were evaluated for their antifungal activity against four fungal pathogens, the soil-borne pathogen Penicillium italicum, the air-borne pathogens Aspergillus niger and Botrytis cinerea, and the antagonistic fungi Trichoderma harzianum to evaluate the possible involvement of such compounds in resistance to pathogen attack.  相似文献   
123.
利用扫描电镜和解剖镜对西藏色季拉山区分布的龙胆科6属20种植物种子微形态进行观察研究。结果显示:这20种植物的种子颜色有黑色、黄色、黑褐色、黄褐色、灰褐色和红棕色6种;种子形状分为长卵球形、卵球形、椭圆球形、矩圆形和近球形;表皮纹饰可分为4种类型,即网纹型、条纹型、疣状型和嚼烂型,其中网纹型又细分为6个亚型。根据种子微形态特征,笔者对龙胆科相关属的进化趋势、分类学意义和分类鉴定等进行了讨论,认为獐牙菜属(Swertia L.)和龙胆属(Gentiana(Tourn.)L.)进化程度较高;从种子微形态特征上看肋柱花属(Lomatogonium A.Br.)、花锚属(Halenia Borkh.)和假龙胆属(Gentianella Moench.)间有较近的亲缘关系;龙胆科各属种子表皮纹饰特征与分类系统基本吻合。本研究表明种子微形态在植物分类研究中具有十分重要的意义,可作为植物系统划分、鉴定和进化研究的参考性状。  相似文献   
124.

Background and Aims

To date, the structure of the nectary spur of Aeridinae has not been studied in detail, and data relating to the nectaries of ornithophilous orchids remain scarce. The present paper compares the structural organization of the floral nectary in a range of Aeridinae species, including both entomophilous and ornithophilous taxa.

Methods

Nectary spurs of Ascocentrum ampullaceum (Roxb.) Schltr. var. aurantiacum Pradhan, A. curvifolium (Lindl.) Schltr., A. garayi Christenson, Papilionanthe vandarum (Rchb.f.) Garay, Schoenorchis gemmata (Lindl.) J.J. Sm., Sedirea japonica (Rchb.f.) Garay & H.R. Sweet and Stereochilus dalatensis (Guillaumin) Garay were examined by means of light microscopy, scanning electron microscopy and transmission electron microscopy.

Key Results and Conclusions

The diverse anatomy of the nectary is described for a range of Aeridinae species. All species of Ascocentrum investigated displayed features characteristic of ornithophilous taxa. They have weakly zygomorphic, scentless, red or orange flowers, display diurnal anthesis, possess cryptic anther caps and produce nectar that is secluded in a relatively massive nectary spur. Unicellular, secretory hairs line the lumen at the middle part of the spur. Generally, however, with the exception of Papilionanthe vandarum, the nectary spurs of all entomophilous species studied here (Schoenorchis gemmata, Sedirea japonica, Stereochilus dalatensis) lack secretory trichomes. Moreover, collenchymatous secretory tissue, present only in the nectary spur of Asiatic Ascocentrum species, closely resembles that found in nectaries of certain Neotropical species that are hummingbird-pollinated and assigned to subtribes Maxillariinae Benth., Laeliinae Benth. and Oncidiinae Benth. This similarity in anatomical organization of the nectary, regardless of geographical distribution and phylogeny, indicates convergence.  相似文献   
125.
Euphorbia (Euphorbiaceae) is one of the largest and most diversified cosmopolitan genera of flowering plants. South‐west Asia is a major centre of diversity and contains c. 65 annual species, 35 of which occur in Iran. In this article, the seed morphology of all Iranian annual species was studied, including E. aulacosperma and E. rhabdothosperma, both new records for Iran. Quantitative and qualitative macro‐ and micromorphological features of seeds and caruncles were investigated using stereomicroscopy and scanning electron microscopy. Caruncle characters (shape, size, colour) and seed characters (shape, size, colour, ornamentation) are often constant and useful in identification and classification. An identification key and scanning electron micrographs are provided for all known Iranian taxa. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 212–234.  相似文献   
126.
Background and Aims: Gross vegetative and floral morphology, as well as modern moleculartechniques, indicate that Cryptocentrum Benth. and SepalosaccusSchltr. are related to Maxillaria Ruiz & Pav. However, theydiffer from Maxillaria in their possession of floral spurs and,in this respect, are atypical of Maxillariinae. The labellarmicromorphology of Maxillaria, unlike that of the other twogenera, has been extensively studied. In the present report,the labellar micromorphology of Cryptocentrum and Sepalosaccusis compared with that of Maxillaria and, for the first time,the micromorphology of the floral spur as found in Maxillariinaeis described. Methods: Labella and dissected floral spurs of Cryptocentrum and Sepalosaccuswere examined using light microscopy (LM) and scanning electronmicroscopy (SEM). Key Results: In each case, the labellum consists of a papillose mid-lobe(epichile), a cymbiform region (hypochile) and, proximally,a spur, which is pronounced in Cryptocentrum but short and bluntin Sepalosaccus. The inner epidermal surface of the spur ofCryptocentrum is glabrous or pubescent, and the bicellular hairs,where present, are unlike any hitherto described for Maxillariinae.Similar but unicellular hairs also occur in the floral spurof Sepalosaccus, whereas the glabrous epidermis lining the spurof C. peruvianum contains putative nectar pores. Conclusions: The labellar micromorphology of Cryptocentrum and Sepalosaccusgenerally resembles that of Maxillaria. The floral spur of Cryptocentrumdisplays two types of organization in that the epidermal liningmay be glabrous (possibly with nectar pores) or pubescent. Thismay have taxonomic significance and perhaps reflects physiologicaldifferences relating to nectar secretion. The trichomes foundwithin the spurs of Cryptocentrum and Sepalosaccus more closelyresemble the hairs of certain unrelated, nectariferous orchidtaxa than those found in the largely nectarless genus Maxillaria,and this further supports the case for parallelism.  相似文献   
127.
Two organic matter horizons developed under a spruce forest and grass vegetation were chosen to demonstrate the impact of a different vegetation cover on the micromorphology, porous system and hydraulic properties of surface soils. Micromorphological studies showed that the decomposed organic material in the organic matter horizon under the grass vegetation was more compact compared to the decomposed organic material in the organic matter horizon under the spruce forest. The detected soil porous system in the organic matter horizon under the spruce forest consisted of two clusters of pores with different diameters that were highly connected within and between both clusters. The soil porous system in the organic matter horizon under the grass vegetation consisted of one cluster of pores with the larger diameters and isolated pores with the smaller diameter. The retention ability of the organic matter horizon under the grass vegetation was higher than the retention ability of the organic matter horizon under the spruce forest. Presented at the International Conference on Bioclimatology and Natural Hazards, Poľana nad Detvou, Slovakia, 17–20 September 2007.  相似文献   
128.
Epicuticular waxes are found on the surface of the plant epidermis as crystal structures which show morphological diversity and may be useful in plant systematics. The aim of this study was to recognise the diversity of the epicuticular wax cover on leaves and stems of Lonicera species (Caprifoliaceae) and to estimate the taxonomic value of wax traits. Adaxial and abaxial sides of the leaves and the stem surface in 35 taxa were investigated through a scanning electron microscope (SEM). The assessment was prepared on the basis of the presence or absence of basic types of wax structures and their dimensions, using categorical response analysis, multiple correspondence analysis and cluster analysis. In the analysed species, we found differences in the wax layer structure on the surfaces of the leaves and stems. Apart from the smooth layer, tubules and platelets can be found. Tubules are considerably more frequent than platelets. In many cases, the same plant part produces more than just one wax type. Our analysis indicates that wax structures are not very informative for the taxonomy of Lonicera, because we observed only a weak correspondence between the presence or absence of some types of wax tubules and the infrageneric classification of the genus. However, in particular cases these new data can be used for species identification.  相似文献   
129.
利用光学显微镜和扫描电镜对海三棱藨草(× Bolboschoenoplectus mariqueter (Tang & F. T. Wang))及其5个近缘种的果实形状、果皮微形态特征进行观察和分析。结果显示,海三棱藨草果实形状为双凸状,表面为波形网状纹饰,外果皮为中果皮厚度的2倍,与扁秆荆三棱( Bolboschoenus planiculmis (F. Schmidt) T. V. Egorova)明显不同,而与海滨三棱草( Bolboschoenus maritimus (L.) Palla)相似。研究结果支持将海三棱藨草归入三棱草属,不支持将海三棱藨草作为扁秆荆三棱的异名,推测其可能为海滨三棱草水滨亚种( Bolboschoenus maritimus subsp. paludosus (A. Nelson) T. Koyama)的异名。  相似文献   
130.
薏苡仁蛋白质组分研究   总被引:1,自引:0,他引:1  
王灵芝  袁建娜  张小华  乔延江 《生物磁学》2012,(23):4416-4418,4432
目的:对药食两用功能的薏苡仁蛋白质四类组分和氨基酸含量进行分析。方法:采用旋光法、索氏提取法、烘干法、马弗炉法分别进行淀粉、粗脂肪、水分和灰分的测定;采用顺序抽提法依次进行清蛋白、球蛋白、醇溶蛋白和谷蛋白的提取,用Brandford和凯式定氮法进行蛋白质含量分析;采用氨基酸分析仪进行氨基酸含量测定。结果:薏苡仁总蛋白含量为14.17%,其中清蛋白、球蛋白、醇溶蛋白和谷蛋白含量分别为0.20、0.88、6.34和5.30mg/100mg鲜重,分别占总蛋白质含量的1.43%、6.20%、44.74%和37.38%;薏苡仁粉经酸水解后共检测到15种氨基酸,除Trp外,人体必需氨基酸和半必需氨基酸均有检测到;各氨基酸含量也存在着差异,含量最高的为Glu(3.59mg/100mg),含量最低的为Met(0.17mg/100mg)。结论:薏苡仁蛋白中醇溶蛋白和谷蛋白含量较丰富,为今后进一步开发薏苡仁功能食品提供了理论数据。  相似文献   
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