Zone Precipitation Chromatography: Its Use in the Isolation of Different Collagen Types

Zone Precipitation Chromatography is useful tech-nique for the initial isolation of the different colla-gen types in their native configuration. Small quan-tities of collagen mixtures can be rapidly separated into different collagen types with relatively high degree of purity, based upon stained protein patterns on sodium dodecyl sulfate polyacrylamide gel electro-phoresis (SDS-PAGE) slab gels. Tn the commonly used bulk salt preparative method for isolating the different collagens, 50 mg of starting material was needed. Three days were required to complete the procedure. The stained protein patterns on SDS-PAGE slab gels showed about 25% contamination with the bulk purified Type III fraction and 20% contamination with the bulk purified type AB collagen. With Zone Precipitation Chromatography 5 mg of starting material was used and in less than 4 hours the mixture was separated with Types III and AB fractions showing less than 10% contamination from other collagen types. The technique is patterned after the Zone Precinitation method reported by Porath seventeen years ago and utilizes a step-wise sodium chloride gradient to precipitate and redissolve the collagens, eluting from the interbead spaces of a molecular sieve column.     

High-throughput RNA extraction from plant samples based on homogenisation by reciprocal shaking in the presence of a mixture of sand and glass beads

We describe here a reliable high-throughput method for extraction of RNA from fresh or frozen plant tissue that obviates laborious and time-consuming homogenisation by mortar and pestle. The method is based on homogenisation by high-speed reciprocal shaking in presence of a mixture of inexpensive abrasive materials; i.e., quartz sand and glass beads. After homogenisation, the method follows a standard procedure for RNA extraction by phenol/LiCl. Yield and quality of RNA obtained by homogenisation with the sand/glass bead mix are identical to those obtained by mortar and pestle.     

Identification of single tiny seeds ofOrobanche using RAPD analysis

The tiny seeds of parasitic weeds of the genusOrobanche can be identified by using RAPD markers. A simple procedure for DNA extraction from single seeds, 10 μg each, followed by RAPD-PCR and using specific DNA markers, leads to species identification. Seeds of five different species could be identified using this method.     

Rapid authentication of animal cell lines using pyrolysis mass spectrometry and auto-associative artificial neural networks

Summary Pyrolysis mass spectrometry (PyMS) was used to produce biochemical fingerprints from replicate frozen cell cultures of mouse macrophage hybridoma 2C11-12, human leukaemia K562, baby hamster kidney BHK 21/C13, and mouse tumour BW-O, and a fresh culture of Chinese hamster ovary CHO cells. The dimensionality of these data was reduced by the unsupervised feature extraction pattern recognition technique of auto-associative neural networks. The clusters observed were compared with the groups obtained from the more conventional statistical approaches of hierarchical cluster analysis. It was observed that frozen and fresh cell line cultures gave very different pyrolysis mass spectra. When only the frozen animal cells were analysed by PyMS, auto-associative artificial neural networks (ANNs) were employed to discriminate between them successfully. Furthermore, very similar classifications were observed when the same spectral data were analysed using hierarchical cluster analysis. We demonstrate that this approach can detect the contamination of cell lines with low numbers of bacteria and fungi; this approach could plausibly be extended for the rapid detection of mycoplasma infection in animal cell lines. The major advantages that PyMS offers over more conventional methods used to type cell lines and to screen for microbial infection, such as DNA fingerprinting, are its speed, sensitivity and the ability to analyse hundreds of samples per day. We conclude that the combination of PyMS and ANNs can provide a rapid and accurate discriminatory technique for the authentication of animal cell line cultures.     

牡丹种皮黄酮提取及对ABTS自由基清除作用

以丹凤牡丹（Paeonia ostii）种皮为原料,采用正交实验法对影响牡丹种皮总黄酮匀浆提取含量的主要因素进行研究分析,考察了乙醇浓度、料液比、匀浆时间、匀浆次数4个因素的影响,筛选出最佳工艺条件,乙醇浓度80%,液料比20∶1,匀浆时间4 min,匀浆次数2次。并在最佳工艺条件下进行验证实验,得牡丹种皮黄酮提取物含量为52.19 mg·g^-1。测定了牡丹种皮黄酮对2,2-联氨-双（3-乙基苯并噻唑啉-6-磺酸）二胺盐(ABTS)自由基的清除效果,结果表明牡丹种皮黄酮的抗氧化能力强于2,6-二叔丁基-4-甲基苯酚(BHT),为牡丹种皮变废为宝提供了科学依据。     

Supercritical carbon dioxide extraction of hydrocarbons from the microalgaBotryococcus braunii

Samples of the microalgaBotryococcus braunii were submitted to supercritical fluid extraction with carbon dioxide at 40 °C and pressures of 12.5, 20.0 and 30.0 MPa. The extraction yield and the fraction of the hydrocarbons in the extracts both increased with pressure and at 30 MPa these compounds were obtained rapidly. This behaviour is associated with the localization of the hydrocarbons outside the cell wall. In the extracts, which are fluid, golden and limpid, chlorophyll and phospholipids were not detected.Author for correspondence     

By-Products of Zea mays L.: A Promising Source of Medicinal Properties with Phytochemistry and Pharmacological Activities: A Comprehensive Review

Zea mays (Z. mays) is one of the main cereal crops in the world, and it′s by-products have exhibited medicinal properties to explore. This article intends to review the chemical compositions and pharmacological activities of by-products of Z. mays (corn silks, roots, bract, stems, bran, and leaves) which support the therapeutic potential in the treatment of different diseases, with emphasis on the natural occurring compounds and detailed pharmacological developments. Based on this review, 231 natural compounds are presented. Among them, flavonoids, terpenes, phenylpropanoids, and alkaloids are the most frequently reported. The by-products of Z. mays possess diuretic effects, hepatoprotective, anti-diabetic, antioxidant, neuroprotective, anti-inflammatory, anti-cancer, plant protection activity, and other activities. This article reviewed the phytochemistry and pharmacological activities of Z. mays for comprehensive quality control and the safety and effectiveness to enhance future application.     

Can indicator species predict restoration outcomes early in the monitoring process? a case study with peatlands

Success in ecological restoration is rarely assessed rigorously due to insufficient planning for post-restoration monitoring programs, limited funding and, especially, lack of scientifically validated evaluation criteria and protocols. In this article, we propose the use of the Indicator Value Index technique (IndVal), which statistically determines the association of species to one or several particular site types, to obtain indicators of success at the early stages of the recovery process in restoration projects. Peat bogs extracted by the vacuum method, subsequently restored by a moss-transfer technique and regularly monitored for ~10 years were used as a model system to test this approach. We first identified 34 restored sectors of ~10 ha from 4 to 11 years old in twelve eastern-Canadian bogs. These sectors were then classified according to their degree of success in recovering a typical sphagnum moss carpet (restoration goal). Then, we retrospectively reviewed vegetation communities recorded at the third year after restoration to identify indicator species of different categories of restoration success, using the IndVal methodology. By identifying early indicator species, our method provides a tool that guides intervention soon after restoration if a site is not on a desired successional trajectory. Typical bog species, namely the bryophytes S. rubellum and Mylia anomala and the tree Picea mariana, were indicative of successful restoration; while bare peat, lichens and one species of ericaceous shrubs (Empetrum nigrum), which cope better under drier conditions, indicated sites where restoration failed. A surprising finding was that the moss Polytrichum strictum, which is known to facilitate the colonization of sphagnum in disturbed peatlands, is an early indicator of unsuccessful restoration. This finding made us question the nursing role of P. strictum at a cover threshold above ca. 30%, when P. strictum could be outcompeting sphagnum and become dominant. We conclude that the IndVal method is an effective tool to identify early indicators of restoration success when combined with a thoughtful examination of species frequency and cover within each site type.