Nondestructive analyses of unsaturated fatty acid species in dietary oils by attenuated total reflectance with Fourier transform IR spectroscopy

The aim of this study was to develop a nondestructive method to quantitate relative amounts of n-3 and n-6 polyunsaturated fatty acid (PUFA) species in vegetable oils and oil seeds using Fourier transform IR spectroscopy (FTIR). The alkene Cbond;H stretching vibrations of unsaturated fatty acids in oils showed IR absorption bands with various peak positions and intensities at around 3010 cm(-1), depending on the extent of unsaturation and PUFA species. With the aid of partial least-squares regression analysis, the FTIR measurement could practically predict the content of each PUFA species in the oil to be tested. A calculation method was also presented to directly find PUFA species in oils from the FTIR spectra. This technique was applied to dried soybean seeds to demonstrate a nonhomogenous distribution of saturated fatty acids and PUFAs, as well as glycans, in soybean cross sections.     

In vivo 13C NMR metabolite profiling: potential for understanding and assessing conifer seed quality

High-resolution 13C MAS NMR spectroscopy was used to profile a range of primary and secondary metabolites in vivo in intact whole seeds of eight different conifer species native to North America, including six of the Pinaceae family and two of the Cupressaceae family. In vivo 13C NMR provided information on the total seed oil content and fatty acid composition of the major storage lipids in a non-destructive manner. In addition, a number of monoterpenes were identified in the 13C NMR spectra of conifer seeds containing oleoresin; these compounds showed marked variability in individual seeds of Pacific silver fir within the same seed lot. In imbibed conifer seeds, the 13C NMR spectra showed the presence of considerable amounts of dissolved sucrose presumed to play a protective role in the desiccation-tolerance of seeds. The free amino acids arginine and asparagine, generated as a result of storage protein mobilization, were detected in vivo during seed germination and early seedling growth. The potential for NMR to profile metabolites in a non-destructive manner in single conifer seeds and seed populations is discussed. It is a powerful tool to evaluate seed quality because of its ability to assess reserve accumulation during seed development or at seed maturity; it can also be used to monitor reserve mobilization, which is critical for seedling emergence.     

A novel noninvasive procedure for high‐throughput screening of major seed traits

The large numbers of samples processed in breeding and biodiversity programmes require the development of efficient methods for the nondestructive evaluation of basic seed properties. Near‐infrared spectroscopy is the state‐of‐the‐art solution for this analytical demand, but it also has some limitations. Here, we present a novel, rapid, accurate procedure based on time domain‐nuclear magnetic resonance (TD‐NMR), designed to simultaneously quantify a number of basic seed traits without any seed destruction. Using a low‐field, benchtop ¹H‐NMR instrument, the procedure gives a high‐accuracy measurement of oil content (R² = 0.98), carbohydrate content (R² = 0.99), water content (R² = 0.98) and both fresh and dry weight of seeds/grains (R² = 0.99). The method requires a minimum of ~20 mg biomass per sample and thus enables to screen individual, intact seeds. When combined with an automated sample delivery system, a throughput of ~1400 samples per day is achievable. The procedure has been trialled as a proof of concept on cereal grains (collection of ~3000 accessions of Avena spp. curated at the IPK genebank). A mathematical multitrait selection approach has been designed to simplify the selection of outlying (most contrasting) accessions. To provide deeper insights into storage oil topology, some oat accessions were further analysed by three‐dimensional seed modelling and lipid imaging. We conclude that the novel TD‐NMR‐based screening tool opens perspectives for breeding and plant biology in general.     

The use of optical spectroscopy in combinatorial chemistry.

Infrared and Raman spectroscopy allow direct spectral analysis of the solid-phase, thus avoiding the tedious cleavage of compounds from the solid support. With diagnostic bands in starting materials or products, infrared and Raman spectroscopy are efficient in monitoring each reaction step directly on the solid phase. Consequently, infrared and Raman spectroscopy have evolved as the premier analytical methodology for direct analysis on the solid support. While infrared transmission spectroscopy is a general analytical method for resin samples, internal reflection spectroscopy is especially suited for solid polymer substrates known as "pins" or "crowns." Single bead analysis is done best by infrared microspectroscopy, whereas photoacoustic spectroscopy allows totally nondestructive analysis of resin samples. With an automated accessory, diffuse reflection spectroscopy provides a method for high throughput on-bead monitoring of solid-phase reactions. Providing identification based on molecular structure, HPLC-FTIR is, therefore, complementary to LC-MS. Additionally, Raman spectroscopy as a complement to infrared spectroscopy can be applied to resin samples and-using a Raman microscope-to single beads. Fluorometry as an extremely sensitive spectroscopic detection method allows rapid quantification of organic reactions directly on the resin.     

Esterase Isozyme of Indigenous Wheat to China

Esterase isozyme of dry seeds, anthers and immature seeds from 54 accessions of indigenous wheat to China was analysed. The result showed the specialties of esterase isozyme in different tissues. There were 12 zymogram types of esterase isozyme in 54 materials. A special marked band, esterase isozyme band 2A, was found in Xinjiang wheat. Cluster analysis suggested that (1) Yunnan wheat was geneticaly close related to Tibet semi-wild wheat. Both of them are in the same level of evolution and belong to one taxonomical group. (2) Common wheat and Tibet common wheat belong to one group and (3) Xinjiang wheat is a special group, having its own evolutionary process.     

Seed longevity of maize conserved under germplasm bank conditions for up to 60 years

Background and AimsThe long-term conservation of seeds of plant genetic resources is of key importance for food security and preservation of agrobiodiversity. Nevertheless, there is scarce information available about seed longevity of many crops under germplasm bank conditions.MethodsThrough germination experiments as well as the analysis of historical monitoring data, we studied the decline in viability manifested by 1000 maize (Zea mays subsp. mays) seed accessions conserved for an average of 48 years at the CIMMYT germplasm bank, the largest maize seedbank in the world, under two cold storage conditions: an active (–3 °C; intended for seed distribution) and a base conservation chamber (–15 °C; for long-term conservation).Key ResultsSeed lots stored in the active chamber had a significantly lower and more variable seed germination, averaging 81.4 %, as compared with the seed lots conserved in the base chamber, averaging 92.1 %. The average seed viability detected in this study was higher in comparison with that found in other seed longevity studies on maize conserved under similar conditions. A significant difference was detected in seed germination and longevity estimates (e.g. p₈₅ and p₅₀) among accessions. Correlating seed longevity with seed traits and passport data, grain type showed the strongest correlation, with flint varieties being longer lived than floury and dent types.ConclusionsThe more rapid loss of seed viability detected in the active chamber suggests that the seed conservation approach, based on the storage of the same seed accessions in two chambers with different temperatures, might be counterproductive for overall long-term conservation and that base conditions should be applied in both. The significant differences detected in seed longevity among accessions underscores that different viability monitoring and regeneration intervals should be applied to groups of accessions showing different longevity profiles.     

Pod,seed traits and cytotaxonomic studies of some Vicia narbonensis L. accessions (Fabaceae)

This study aimed to characterize eight accessions of Vicia narbonensis L. originated from different Mediterranean countries. The cytology of these species is rarely known despite the fact of its great socio-economical and ecological interest in these arid and semi-arid zones. This work aimed mainly to characterize the karyotype, morphological pod and seed traits of the species. Karyotypes of all accessions were similar to a diploid number of 2n = 2x = 14. All the accessions have submetacentric chromosomes with a secondary constriction attached to the long arm of pair VII close to the centromere. Variation in chromosome size was observed; it ranged from 5.86 μm to 7.62 μm. Indices of karyotype asymmetry were calculated as the total form percentage (TF%) and symmetric indices (Syi) which ranged from 33.75% to 35.42% and from 51.01% to 54.85%, respectively. The predominance of submetacentric chromosomes indicated that the karyotype is symmetrical and can be considered as primitive. However, the analysis of quantitative parameters measured on pods and seeds showed a significant variation between accessions. A relationship between centromeric index and the pod beak length was found. Estimation of phenotypic diversity using the Shannon diversity index (H′) showed that the length, the seed color and the number of seeds per pod are the most polymorphic traits with respectively, H′ = 0.92, 0.80 and 0.83. Cluster analysis of karyological, pod and seed traits showed four groups of accessions. This clustering is partially due to the geographical origin of the studied accessions. The variation in chromosome size, pod and seed traits could offer potentially valuable genetic resources for the improvement of V. narbonensis which is considered as neglected and underutilized crop species (NUCS).     

Seed storage protein variation in Arachis species.

Seventy-two accessions, representing 22 species from sections Arachis, Erectoides, Extranervosae, and Triseminalae of the genus Arachis, were screened for seed storage protein polymorphism. Variation was detected between sections, between genome types, between species, and in some cases between different accessions of the same species or different seeds of the same accession. Arachis duranensis and one accession of A. cardenasii were found to have identical protein patterns. The greatest dissimilarity was found between species of the section Extranervosae and species of the section Triseminalae. Those of section Erectoides showed much similarity with some species of section Arachis. Protein polymorphism was shown to distinguish the two subspecies of A. hypogaea (fastigiata and hypogaea) in 27 of 28 cases. The seed protein profile of A. monticola was a combination of seed protein profiles from the two A. hypogaea subspecies. The relatedness between the various species was calculated and those that had the greatest similarity with A. hypogaea were A. spegazzinii and A. batizocoi.     

功能红细胞研究的拉曼光谱技术与进展

红细胞在人体新陈代谢和物质运输方面起着非常重要的作用。作为一种无损、快速而灵敏的光谱学检测方法,拉曼光谱技术在生物医学领域的应用日渐广泛。本文综述了近年来拉曼光谱技术在红细胞及血红蛋白研究中的应用进展,详尽评述当前研究功能红细胞中较有优势的拉曼技术—显微拉曼光谱技术和光镊拉曼光谱技术,并对其技术的改进做出总结,以期为利用激光拉曼光谱研究红细胞提供较系统的参考。     

The use of optical spectroscopy in combinatorial chemistry

Infrared and Raman spectroscopy allow direct spectral analysis of the solid‐phase, thus avoiding the tedious cleavage of compounds from the solid support. With diagnostic bands in starting materials or products, infrared and Raman spectroscopy are efficient in monitoring each reaction step directly on the solid phase. Consequently, infrared and Raman spectroscopy have evolved as the premier analytical methodology for direct analysis on the solid support. While infrared transmission spectroscopy is a general analytical method for resin samples, internal reflection spectroscopy is especially suited for solid polymer substrates known as “pins” or “crowns.” Single bead analysis is done best by infrared microspectroscopy, whereas photoacoustic spectroscopy allows totally nondestructive analysis of resin samples. With an automated accessory, diffuse reflection spectroscopy provides a method for high throughput on‐bead monitoring of solid‐phase reactions. Providing identification based on molecular structure, HPLC‐FTIR is, therefore, complementary to LC‐MS. Additionally, Raman spectroscopy as a complement to infrared spectroscopy can be applied to resin samples and—using a Raman microscope—to single beads. Fluorometry as an extremely sensitive spectroscopic detection method allows rapid quantification of organic reactions directly on the resin. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng (Comb Chem) 61:179–187, 1998/1999.     

联合应用ESI MS和1H NMR分析含笑属植物种子磷脂

首次尝试利用电喷雾电离质谱(ESI MS)和氢原子核磁共振(1 H NMR)技术分析了含笑属六种植物种子的磷脂特性,发现在两个指纹图谱区发现明显的差异,即在质荷比(m/z)895-910(ESI MS)和5.30～5.40mg/L(1 H NMR)两个特异的区域存在显著差异。这些源于种子磷脂ESI/MS和1 H NMR的谱带差异可以被用来分析不同植物的种子的磷脂特征。而且,相似地,在更广的层面上,特异性的谱带差异可用于分析其他植物种子的磷脂组成和特性,辅助鉴定种子。     

Widespread occurrence of Neotyphodium-like endophyte in populations of Bromus tomentellus Boiss. in Iran

Neotyphodium species occur as endophytic fungi in cool-season grasses around the world. The beneficial aspects of grass-Neotyphodium associations have provoked researchers to look for a novel association in plant species where this symbiotum has not been reported. We surveyed Russian bromegrass (Bromus tomentellus Boiss.) accessions from a germplasm collection for the presence of Neotyphodium spp. fungi and determined levels of endophyte infection in B. tomentellus populations in native rangelands of Iran. Among 50 collected accessions, symbiotic fungi were detected in 45 accessions without any symptoms of choke disease on host plants. In culture medium, fast-growing endophytes appeared from seeds after 7-14 days. Plants grown from seed collections were 80-100% infected. Based on morphological characteristics and PCR analysis, we concluded that this fungus is a member of the Neotyphodium group of endophytic fungi. Lack of apparent toxicity to grazing animals suggests a place for endophyte-infected B. tomentellus in rangeland renovation, providing this infected grass exhibits increased tolerance to abiotic stresses.     

Determination of Seed Soundness in Conifers Cryptomeria japonica and Chamaecyparis obtusa Using Narrow-Multiband Spectral Imaging in the Short-Wavelength Infrared Range

Regeneration of planted forests of Cryptomeria japonica (sugi) and Chamaecyparis obtuse (hinoki) is the pressing importance to the forest administration in Japan. Low seed germination rate of these species, however, has hampered low-cost production of their seedlings for reforestation. The primary cause of the low germinability has been attributed to highly frequent formation of anatomically unsound seeds, which are indistinguishable from sound germinable seeds by visible observation and other common criteria such as size and weight. To establish a method for sound seed selection in these species, hyperspectral imaging technique was used to identify a wavelength range where reflectance spectra differ clearly between sound and unsound seeds. In sound seeds of both species, reflectance in a narrow waveband centered at 1,730 nm, corresponding to a lipid absorption band in the short-wavelength infrared (SWIR) range, was greatly depressed relative to that in adjacent wavebands on either side. Such depression was absent or less prominent in unsound seeds. Based on these observations, a reflectance index SQI, abbreviated for seed quality index, was formulated using reflectance at three narrow SWIR wavebands so that it represents the extent of the depression. SQI calculated from seed area-averaged reflectance spectra and spatial distribution patterns of pixelwise SQI within each seed area were both proven as reliable criteria for sound seed selection. Enrichment of sound seeds was accompanied by an increase in germination rate of the seed lot. Thus, the methods described are readily applicable toward low-cost seedling production in combination with single seed sowing technology.     

Raman spectroscopic monitoring of Lactarius latex

Lactarius is a genus of Basidiomycotina with mainly agaricoid representatives, which are characterised by the excretion of a typical milky fluid. In particular, the colour, changes and taste of this latex-like milk are often used as a taxonomically important character. When it is exuded several chemical reactions occur. To date, NMR spectroscopy is generally used for chemical investigation of this latex. However, as a vibrational spectroscopic technique Raman spectroscopy has several advantageous properties for this type of research. The aim of this study is to investigate whether Raman spectroscopy can be used as an alternative analytical technique to monitor the chemical reactions in Lactarius latex. Therefore, this paper presents the first Raman spectra of Lactarius latex and provides an interpretation of the Raman bands that are present. L. lacunarum latex spectra are thoroughly investigated by 2D correlation analysis and are compared with latex spectra of other species (L. chrysorrheus, L. deterrimus, L. fluens, L. glyciosmus and L. salmonicolor).     

拉曼光谱技术在肿瘤检测中的应用

癌症是威胁人类健康和生命的严重疾病之一,早期诊断与及时治疗是提高癌症患者生存率的最有效途径。激光拉曼光谱技术作为一种非侵入性的检测技术,可以无损伤地提供丰富的分子结构特征和物质成分信息,从分子水平上反映癌变组织与正常组织之间的结构差异,从而可用于癌症的早期诊断。综述了激光拉曼光谱技术在皮肤癌、鼻咽癌、肺癌、胃癌、结肠癌、乳腺癌及前列腺癌诊断中的研究进展,并对拉曼光谱技术在癌症诊断中的发展方向和应用前景作了进一步的展望,为癌症的早期检测和诊断技术的应用研究提供参考依据。     

Variation between Emex australis populations in seed dormancy/non-dormancy cycles

Abstract Seeds of four Western Australian accessions of Emex australis were stored outside and their germinability tested at 4–6 week intervals for 22 months. Accessions showed cyclical behaviour in germinability, with peaks in autumn/early winter and troughs in spring/summer. There was considerable variation between accessions in dormancy/non-dormancy cycles, but when plants from accessions with contrasting cycles were grown in a common environment, the cycles shown by their seeds were virtually identical. Thus, the parameters of seed dormancy/non-dormancy cycles in E. australis appear to be under environmental control. Only part of an E. australis seed population demonstrated cyclical changes in dormancy status, in contrast to many other annual species whose entire seed populations undergo such changes. Populations also contained individuals which were either continuously dormant or continuously non-dormant following a period of after-ripening. The latter seeds give E. australis the flexibility to recruit opportunistically after summer rainfall events in mediterranean-climate environments.     

Seed Stores for Restoration of Species-Rich Shrubland Vegetation Following Mining in Western Australia

The extreme species richness of native shrubland vegetation (kwongan) near Eneabba, Western Australia, presents a major problem in the restoration of sites following mineral sand mining. Seed sources available for post-mining restoration and those present in the native kwongan vegetation were quantified and compared. Canopy-borne seeds held in persistent woody fruits were the largest seed source of perennial species in the undisturbed native vegetation and also provided the most seeds for restoration. In undisturbed vegetation, the germinable soil seed store (140–174 seeds · m^?2) was only slightly less than the canopy-borne seed store (234–494 seeds · m^?2), but stockpiled topsoil provided only 9% of the germinable seeds applied to the post-mining habitat. The age of stockpiled soil was also important. In the three-year-old stockpiled topsoil, the seed bank was only 10.5 seeds · m^?2 in the surface 2.5 cm, compared to 56.1 to 127.6 seeds · m^?2 in fresh topsoil from undisturbed vegetation sites. In the stockpiled topsoil, most seeds were of annual species and 15–40% of the seeds were of non-native species. In the topsoil from undisturbed vegetation, over 80% of the seeds were of perennial species, and non-native species comprised only 2.7% of the seed bank. Additional seeds of native species were broadcast on restoration areas, and although this represented only 1% of the seed resources applied, the broadcast seed mix was an important resource for increasing post-mining species richness. Knowledge of the life-history characteristics of plant species may relate to seed germination patterns and assist in more accurate restoration where information on germination percentages of all species is not available.     

The Optical Absorption Coefficient of Maize Seeds Investigated by Photoacoustic Spectroscopy

The knowledge about a seed??s optical parameters is of great relevance in the seed technology practice. Such parameters provide information about its absorption and reflectance, which in turn is related to its color, quality, and health condition. The objective of the present study was to determine the optical absorption coefficient ?? for maize seeds (Zea mays L.) by means of the photoacoustic spectroscopy (PAS). Untreated seeds (I) and seeds dyed with methyl red (II) were used in this investigation. In addition, conventional reflectance measurements (obtained with the integrating sphere) were performed to validate PAS absorption measurements. The results show that the absorption spectra and reflection data of the seed samples are complementary. When used with thermally thick and optically opaque seeds, PAS may be considered as a potential diagnostic tool for the characterization of the seeds.