Effects of different carbon sources and C/N values on nonvolatile taste components of Pleurotus eryngii

Pleurotus eryngii, the second largest industrial cultivation mushroom in China, is usually cultivated on substrates mainly consisting of sawdust and corncob. In this study, experiments were performed to determine the effects of different carbon sources and C/N values on nonvolatile taste components of P. eryngii. The effects of different carbon sources on nonvolatile taste components levels revealed that sawdust was beneficial to high levels of crude protein, amino acids, 5′‐nucleotides and equivalent umami concentration, while corncob was beneficial to high contents of carbohydrate, polysaccharides and trehalose. At the similar C/N values, relatively higher sawdust content was beneficial to umami amino acid production, while relatively higher corncob content was beneficial to high contents of carbohydrate, polysaccharides and mannitol. Higher C/N value was beneficial to high levels of crude protein, amino acids, 5′‐nucleotides and equivalent umami concentration, while lower C/N value was beneficial to high contents of carbohydrate, polysaccharides and trehalose. These results provided information for P. eryngii fruit body industrial cultivation to obtain specific nonvolatile taste components with high levels.     

Chemical composition,antibacterial and antioxidant activity of the essential oils of Metaplexis japonica and their antibacterial components

The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Metaplexis japonica and isolation of antibacterial constituents from the essential oils. Results showed that 63 components were identified in essential oils. Phenylethyl alcohol (77.978%), α‐terpineol (31.810%) and docosane (21.644%) were the most abundent constituents of flower oil, leaf oil and fruit oil, respectively. Based on bioactivity‐guided fractionation, three active constituents were isolated and identified as phenylethyl alcohol, α‐terpineol and β‐linalool. Both flower oil and phenylethyl alcohol showed high antibacterial performance, with inhibition zone from 25 ± 0.5 to 11 ± 0.6 mm at highest concentration, and MIC values ranging from 0.125 to 2%. In both DPPH and ABTS assay, the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of M. japonica to control food‐borne pathogenic and spoilage bacteria.     

The Mahalanobis Distance for Functional Data With Applications to Classification

This article presents a new semidistance for functional observations that generalizes the Mahalanobis distance for multivariate datasets. The main characteristics of the functional Mahalanobis semidistance are shown. To illustrate the applicability of this measure of proximity between functional observations, new versions of several well-known functional classification procedures are developed using the functional Mahalanobis semidistance. A Monte Carlo study and the analysis of two real examples indicate that the classification methods used in conjunction with the functional Mahalanobis semidistance give better results than other well-known functional classification procedures. This article has supplementary material online.     

Tea components influencing bioavailability of fluoride and potential transport mechanism in the Caco-2 cell line model

Previous work showed that the bioavailability of fluoride in dark tea was lower than NaF solution. However, limited information is available indicating the effects of tea components on the fluoride bioavailability. In this study, the effects of the components in tea on the bioavailability of fluoride were evaluated in the Caco-2 cell line model. Additionally, the mechanism of effect of aluminium on fluoride transport was investigated. The result showed that 10–100 μm of epigallocatechin gallate (EGCG) could not influence fluoride transport. Al³⁺ significantly decreased fluoride transport in both apical-basolateral and basolateral-apical directions. Moreover, aluminium could form different forms of aluminium fluoride complexes, which were transported through Caco-2 cells by different pathways. F⁻ transport was mainly dependent on the paracellular pathway and active transport involving Cl⁻ channels. The paracellular pathway played a predominant role in transport of AlF₃. The paracellular pathway and active transport both participated in AlF₂⁺ transport.     

枸杞深加工产品开发现状及研究进展

枸杞作为一种药食同源的经济林果,富含多糖、类胡萝卜素、类黄酮、甜菜碱、牛磺酸等多种功能性成分,具有增强免疫调节、抗衰老、预防癌症和肿瘤生长、降低血糖和血脂水平等多种功效,消费者对枸杞相关产品的需求也日益增加。枸杞生长性状属无限花序,果实成熟期较长为每年6～10月份;然而,枸杞果实在成熟后期快速软化,使其极易受到机械损伤和病原微生物侵染,限制果实的贮藏和运输;因此,在果实成熟期为降低枸杞果实的损耗和迎合消费者对枸杞保健功能的需求,需要在成熟期内对果实进行深加工处理。阐述了枸杞的主要营养价值和保健功效,并提出传统加工产业与现代消费升级引起的供需矛盾;介绍了枸杞深加工产品和配套技术设备的相关产业现状,分析了枸杞产业精深加工的市场需求和产品研发的未来发展趋势,并指出了枸杞深加工产品和新技术、新装备在枸杞深加工产业的应用前景以及面临的难题和挑战,为枸杞深加工产业的发展提供理论参考。     

Trade‐Offs in Seed Dispersal Strategies Across Riparian Trees: The How Matters as Much as the When

Riparian Salicaceae are prolific producers of short‐lived seeds that require very restrictive hydro‐geomorphic conditions for establishment. It is generally assumed that if floods are able to create nursery sites timed with seed dispersal, recruitment will occur. Other spatial and temporal seed dispersal patterns besides the dispersal period have historically received little attention. However, seed dispersal patterns can be highly variable between regions, species and over the years. In this paper, we report the seed dispersal patterns of three dominant riparian Salicaceae trees in Europe: Populus alba, P. nigra and Salix alba to suggest possible trade‐offs between seed dispersal patterns, germinability, longevity and establishment. Seed rain of the three species was monitored in 33 glue‐coated traps for three months yearly from 2006 to 2008 in an 8‐km stretch of the Middle Ebro River (N Spain), which has a pluvio‐nival regime. P. alba dispersed seeds earlier during a shorter time period and with a fewer number of seed release pulses compared with P. nigra, and especially with S. alba. With overlapping seed dispersal periods, the two latter species occupy similar landform units but rarely compete with P. alba, usually at higher elevations, as shown in a previous study in the same study area. The three species had very high germinability immediately after release (>90%), but longevity in S. alba was eight times shorter than that of its two Populus counterparts. We suggest that S. alba has compensated its lower seed quality with a more spaced seed release in several pulses of similar magnitude. With similar seed dispersal patterns and germinability but a higher longevity, P. nigra had a much higher density of individuals than S. alba in the recruitment zones of the study area. We hope that our results may inform river managers about how to optimize river flows to promote sexual regeneration of these species. Copyright © 2015 John Wiley & Sons, Ltd.     

钛石膏的性能研究

钛石膏为硫酸法钛白生产过程中的副产品,钛石膏大量堆积对环境造成污染,研究钛石膏的性能特点,对于选择合理的回收利用方案具有重要的指导意义。主要对钛石膏的物相组成、脱水温度、脱水时间和凝结特点进行试验研究。结果表明:钛石膏的主要物相为二水硫酸钙,少量物相为白云石,钛石膏脱除结晶水温度控制在200℃左右,脱除结晶水时间控制在50 min左右较适宜。添加柠檬酸作缓凝剂时,煅烧温度从120℃提高到200℃,钛石膏的凝结时间从1 800 s缩短为1 000 s,可以满足浇注成型的时间要求。     

Assessment of the radiation impact of steam generator dismantling on the workers,public and environment

Prediction of the exposure of workers and the impact on the public and environment is necessary for the planning of the decommissioning tasks. Planning and realisation of the dismantling process have to take into account many factors. This results in the creation of possible dismantling scenarios. Moreover, the input data such as nuclide composition and activity content often vary. In the case of a steam generator, the contamination level can differ even within the same nuclear power plant. The paper describes and applies the methodology used for complex analysis of the steam generator dismantling process in nuclear power plants using the VVER-440 reactor types.     

Application of principal components analysis and signal-to-noise ratio for calibration of spectrophotometric analysers of food

Spectrophotometric analysers of food, being instruments for determination of the composition of food products and ingredients, are today of growing importance for food industry, as well as for food distributors and consumers. Their metrological performance significantly depends on the numerical performance of available means for spectrophotometric data processing; in particular – the means for calibration of analysers. In this paper, a new algorithm for this purpose is proposed, viz. the algorithm using principal components analysis. It is almost as efficient as partial least squares algorithms of calibration, but much simpler. It is fully automatic, viz. the selection of the most informative components is based on the signal-to-noise ratio characterising processed measurement data. The practical effectiveness of the proposed algorithm is demonstrated on a test problem consisting in determination of the concentrations of components of trinary oil mixtures.