松乳菇菌种分离及菌丝生长特性的研究

以野生松乳菇子实体为材料,分别取不同组织进行菌种分离。用 PDA 培养基培养纯化,筛选出8株菌株,取生长快的菌丝体用不同固体平板培养研究其人工培养特性。结果表明:叶柄间分离到的菌丝生长最快;葡萄糖为最佳碳源;乙酸铵为最佳氮源,其次是玉米浆和蛋白胨;不同培养基的最适 pH 分别是:配方1pH5.0～5.5,配方2pH5.5～6.0,配方3pH6.0～6.5。     

碳、氮和磷对松乳菇生长及矿质营养的影响

选用L9(34)正交表,设置了碳源、氮源和磷量的三因素三水平试验,以探索适于松乳菇生长和矿质营养吸收的最佳培养基。结果表明:9种培养基对松乳菇生长和矿质养分含量均有明显影响。三因素中,对菌丝体生长、K、Ca吸收影响最大的是碳源,对Fe、Mn吸收影响最大的是氮源,对P、Mg、Zn吸收影响最大的是P量。碳源中,可溶性淀粉效果最佳,可使生物量增加32.20%,P、K、Zn含量分别增加16.94%、182.81%,59.09%;氮源中,酒石酸铵最利于菌丝体生长,尿素最利于P、K吸收,谷氨酸最利于Mg、Fe、Mn吸收;P量中,0.5 g/L KH2PO4最适于菌丝体生长和对P、K、Mg、Zn的吸收。促进松乳菇生长和矿质营养吸收的优化组合是:可溶性淀粉18.0 g/L+酒石酸铵0.5 g/L+KH2PO40.5 g/L。     

松乳菇菌丝体深层培养营养需求及发酵条件研究

松乳菇是一种对人体有益的食用菌。研究了松乳菇的深层液体培养所需的碳源、氮源等营养因素,以及发酵的温度和pH值。试验表明:松乳菇菌丝生长的最佳碳源是可溶性淀粉,最佳氮源是甘氨酸。菌丝生长最适宜的温度是27℃,喜中性的生长环境,pH为7.0时生长最好。     

鲍鱼菇发酵培养基的优化

采用液体培养的方法,从6种碳源和7种氮源中筛选出鲍鱼菇菌丝体生长较适的3种碳、氮源。然后选取常见的3种无机盐,运用正交试验的方法,设计三因素三水平的正交试验,筛选出鲍鱼菇菌丝体生长和胞外多糖产生的最优液体培养基。结果表明：利于鲍鱼菇菌丝体生长的液体培养基(g/100mL)为：红糖2、酵母浸粉0.3、MgSO4 0.1;利于鲍鱼菇胞外多糖产生的液体培养基(g/100mL)为：果糖2、牛肉膏0.3、KH2PO4 0.1。     

松乳菇营养成分分析及松乳菇多糖的提取分离

以野生鲜松乳菇子实体、发酵所得菌丝体为材料,对其粗蛋白、氨基酸、脂类总量、多糖、灰分及微量元素的含量进行测定,并以正交法确定了松乳菇多糖提取的最佳工艺条件,以层析法定性分析了多糖的组成。     

松乳菇营养成分分析及松乳菇多糖的提取分离

以野生鲜松乳菇子实体、发酵所得菌丝体为材料,对其粗蛋白、氨基酸、脂类总量、多糖、灰分及微量元素的含量进行测定,并以正交法确定了松乳菇多糖提取的最佳工艺条件,以层析法定性分析了多糖的组成。      

姬菇菇脚对红曲霉菌丝生长和产色素的影响

为调查以姬菇菇脚为底物进行液态发酵生产天然红曲色素的可行性,作者采用平板培养和液态发酵技术,以平板菌落直径、发酵液菌丝体生物量和色素产量为指标,评估姬菇菇脚对紫红曲霉MR02菌丝生长和产色素能力的影响。结果表明,普通培养基添加姬菇菇脚能促进紫红曲霉MR02菌丝体的生长和色素产量的提高;以不同配比的菇脚和大米粉为底物进行培养,在单一菇脚为底物的培养液中测得一定量的菌丝体和红曲色素;以菇脚为底物培养紫红曲霉MR02,其生长特性符合多细胞生物的生长曲线规律;以不同质量分数的姬菇菇脚为底物发酵,菇脚质量分数为12%,培养到第144小时时,菌丝体生物量为5.52 g/L,培养到第216小时时,红曲色素产量为72.92 U/mL。因此,以紫红曲霉MR02为出发菌株,利用姬菇菇脚为底物发酵生产红曲色素是可行的。     

大绿菇菌丝体富锌能力的研究

对大绿菇菌丝体进行液体富锌培养。首先对大绿菇的耐锌和富锌特性进行研究,结果表明:大绿菇具有很强的耐锌能力和富锌能力,其菌丝体在锌浓度为50～2000mg/L的固体培养基上均能够生长;菌丝体对锌的最适富集质量浓度为200mg/L,超过300mg/L锌质量浓度对菌丝体的生长有较大影响。本试验还对富锌培养条件进行优化,在培养温度26℃,起始pH5～6,振荡速度100r/min,250mL三角瓶装液75mL,接种量15%(V∶V),培养基中锌添加量为200mg/L时,大绿菇菌丝的生物转化量及菌丝体富锌率最高,此时菌丝体生物量达到8.79g/L,菌丝体含锌量为2.530mg/g,富锌率为10.51%。对锌的有机化研究结果表明:大绿菇能将锌转化形成体内共价结合的有机锌,而不是简单的物理吸附,且其有机化程度在81.6%左右。     

长根菇菌丝培养、鉴定及氨基酸成分分析

采用组织分离法,选择不同培养条件(温度、pH 值),获得长根菇的纯培养物。扫描电镜观测其菌丝体特征,结合ITS 区序列鉴定菌丝体,用全自动氨基酸分析仪分别测定长根菇子实体、菌丝体氨基酸组成。结果表明：长根菇菌丝最佳生长温度为26℃,最佳生长pH 值为5.0;菌丝体ITS 区序列与子实体完全一致(850bp),ITS 区基因片段的分子鉴定简便、准确,可以作为长根菇菌丝体鉴定的有效手段。长根菇菌丝体、子实体总氨基酸含量分别为18.25%、13.98%,必需氨基酸含量分别为6.97%、5.28%,非必需氨基酸含量分别为11.28%、8.70%,可见长根菇氨基酸种类丰富,营养价值高,长根菇菌丝体可开发成为功能性运动食品。     

松乳菇多糖提取工艺优化及抗氧化活性评价

为了探索松乳菇菌丝体多糖的最佳提取工艺,并对其多糖进行体外抗氧化活性初步研究。采用超声波辅助浸提的方法,以温度、时间、料液比和次数进行单因素实验;在此基础之上,利用Box-Benhnken方法进行四因素三水平实验设计,以多糖得率为响应值,进行响应面分析;通过测定多糖清除DPPH自由基、OH自由基和O₂^-自由基的能力来评价其抗氧化活性,并与维生素C进行对比。结果表明,松乳菇多糖最佳提取工艺条件为:提取温度92.8 ℃、提取时间1.6 h、料液比1:28 (g:mL)和提取次数3次,此条件下松乳菇多糖得率预测值为10.60%,实测值为10.41%,与预测值相对误差为1.79%,说明优化工艺可行。松乳菇多糖对DPPH自由基、OH自由基和O₂^-自由基都具有一定的清除能力,其IC₅₀值分别为0.855,1.147,1.126 mg/mL;但与维生素C比较,其抗氧化活性较弱。热水浸提法提取松乳菇多糖高效、简单、低成本,可用作松乳菇多糖的提取工艺;松乳菇多糖具有明显的体外抗氧化活性。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the