番木瓜及其深加工制品中转基因成分定性PCR检测方法的建立(英文)

本研究对番木瓜不同材料及其深加工制品的核酸提取方法进行了优化,成功提取出可用于PCR扩增反应的DNA。选取番木瓜特异性的内源蛋白PAPAIN基因片段作为内参基因,用于检验提取DNA的质量,有效避免了PCR反应的假阴性并能用于确定检测样品中是否含有番木瓜成分。选取国内目前应用比较多的外源目的基因环斑病毒外壳蛋白(CP)基因以及复制酶(RP)基因作为品系鉴定的基因。本方法适用于出入境检验检疫部门和农业部门对转基因番木瓜及其制品的检验监测。     

微波膨化番木瓜混合脆片工艺研究

以番木瓜为主要原料，马铃薯淀粉、糯米淀粉和玉米淀粉为配料，对番木瓜混合脆片的加工工艺进行研究。结果表明，添加15％马铃薯淀粉和15％糯米淀粉，预干后水份含量在10％，采用微波功率为800W，微波膨化时间为25s，膨化后脆片的感官品质最佳。     

添加不同酒对红烧肉水分迁移及食用品质的影响

为探究添加不同酒对红烧肉的食用品质和水分迁移规律的影响,本实验以添加黄酒、木瓜酒、啤酒和混合酒烹制的红烧肉为研究对象,运用低场核磁共振仪（low-field nuclear magnetic resonance, LF-NMR）和质构仪、卡路里量热仪等检测红烧肉食用品质、质构特性、营养成分和内部水分弛豫时间等指标的变化。结果显示,通过感官评价得知,黄酒组的红烧肉整体可接受度较高;而木瓜酒组红烧肉的脂肪、蛋白质和卡路里含量数值最高,分别为51.95、38.55 g/100 g和623.50 kcal/100 g;啤酒组的水分含量最高,含量高达31.55 g/100 g;黄酒组红烧肉的硬度和剪切力值最低,分别为31.54和2.06 N,肉样达到理想口感和嫩度;黄酒组的L*（亮度）值和a*（红度）值较高,色泽更加红亮。通过低场核磁共振分析发现,啤酒组的弛豫时间T₂₁最短,水与底物结合更紧密,不容易流失,木瓜酒组的弛豫时间T₂₂最长以及峰面积T₂₂最大,红烧肉中的自由水含量最高。综上所述,烹制红烧肉过程中添加黄酒烹制的红烧肉成品各方面综合最佳,其次为混合酒（黄酒＋啤酒）组效果次之。该研究结果为红烧肉的工业化生产提供了参考,也为进一步探究酒对中华传统菜肴质地、滋味的影响机制提供一定的基础。     

European intercomparison on electron spin resonance identification of irradiated foodstuffs

The results of a co-trial organized by the Community Bureau of Reference on the use of Electron Spin Resonance spectroscopy for the identification of irradiated food in 21 laboratories are presented. The trial was qualitative on beef and trout bones, sardine scales, pistachio nut shells, dried grapes, and papaya, and quantitative on poultry bones. There was no difficulty in identifying irradiated meat bones, dried grapes, and papaya. In the case of fish bones there is a need for further kinetic study on different species. Identification of irradiation in pistachio nuts is more complicated and additional research is needed before further trials. All laboratories were able to distinguish between chicken bones irradiated at 1 to 3 kGy or 7 to 10 kGy although there was a partial overlap between the results.     

Update on the development of virus-resistant papaya: virus-resistant transgenic papaya for people in rural communities of Thailand

Papaya (Carica papaya L.) is one of the most important and preferred crops in rural communities in Thailand. Papaya ringspot virus (PRSV) is a serious disease of papaya throughout Thailand. Efforts to control the virus by various methods either have not been successful or have not resulted in sustainable control. In 1995, collaborative research by the Department of Agriculture of Thailand and Cornell University to develop transgenic papaya resistant to PRSV was initiated. Two local Thai cultivars were transformed by microprojectile bombardment with the use of a nontranslatable coat protein gene of PRSV from Khon Kaen. Numerous kanamycin-resistantplants were regenerated and were inoculated with the PRSV Khon Kaen isolate for selection of resistant lines. Since 1997, promising RO transgenic lines have been transferred to the research station at Thapra for subsequent screenhouse tests and selection of the most PRSV-resistant lines. In selection set 1, three R3 lines initially derived from Khaknuan papaya showed excellent resistance to PRSV (97% to 100%) and had a yield of fruit 70 times higher than nontransgenic Khaknuan papaya. In selection set 2, one R3 line initially derived from Khakdam papaya showed 100% resistance. Safety assessments of these transgenic papayas have so far found no impact on the surrounding ecology. No natural crossing between transgenic and nonmodified papaya was observed beyond a distance of 10 m from the test plots. Analysis of the nutritional composition found no differences in nutrient levels in comparison with the nonmodified counterparts. Molecular characterization by Southern blotting revealed three copies of the transgene presented; however, no coat protein product was expressed. Data on additional topics, such as the effects offeeding the transgenic papaya to rats and the stability of the gene inserts, are currently being gathered.     

A papaya-specific gene, papain, used as an endogenous reference gene in qualitative and real-time quantitative PCR detection of transgenic papayas

Genetically modified (GM) papaya lines have been approved for commercialization and are widely cultivated in many countries. As a step towards the development of reliable qualitative and quantitative PCR methods for detecting GM papayas, one papaya (Fructus Caricae Carica papaya L.) species specific gene, papain, was selected and validated as suitable for using as an endogenous reference gene in transgenic papaya PCR detection. In this article, both qualitative and quantitative PCR assays for the papain gene were assayed with 11 different papaya varieties and identical amplification products were obtained with all of them. No amplified fragments could be detected when DNA samples from 18 kinds of other species were used as templates, which demonstrated that this system was specific for papaya. In real-time quantitative PCR analysis, the detection limit was as low as 10 pg of DNA. Southern blot analysis confirmed that the papain gene was two copies in the tested papaya varieties and no allelic variation was testified among these tested papaya varieties. In addition, the common used exogenous genes of the coat protein (CP) and the replicase (RP) were also assayed in qualitative and real-time quantitative PCR. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Wentao Xu and Weibin Bai contributed equally to this work.     

野木瓜在食品工业中的应用前景

野木瓜是我国特有的野生果品之一,其用途广泛,既可以用来观赏,也可以用来加工成各种可口和营养的食品,并且其药用价值已有三千多年的应用历史.介绍了野木瓜的主要生理活性成分及其在食品中的应用前景,为野木瓜的进一步开发和利用提供科学依据.     

Application of a qualitative and quantitative real-time polymerase chain reaction method for detecting genetically modified papaya line 55-1 in papaya products

Genetically modified (GM) papaya (Carica papaya L.) line 55-1 (55-1), which is resistant to papaya ringspot virus infection, has been marketed internationally. Many countries have mandatory labeling regulations for GM foods, and there is a need for specific methods for detecting 55-1. Here, an event- and construct-specific real-time polymerase chain reaction (PCR) method was developed for detecting 55-1 in papaya products. Quantitative detection was possible for fresh papaya fruit up to dilutions of 0.001% and 0.01% (weight per weight [w/w]) for homozygous SunUp and heterozygous Rainbow cultivars, respectively, in non-GM papaya. The limit of detection and quantification was as low as 250 copies of the haploid genome according to a standard reference plasmid. The method was applicable to qualitative detection of 55-1 in eight types of processed products (canned papaya, pickled papaya, dried fruit, papaya-leaf tea, jam, puree, juice, and frozen dessert) containing papaya as a main ingredient.     

米饭饮食与血糖控制

米饭作为亚洲多数国家的主食,对饮食健康具有重要的影响。米饭通常被认为是一种高血糖指数的食物,但米饭摄入与2型糖尿病风险是否相关仍存在争议。本文梳理了有关米饭摄入和2型糖尿病风险之间的流行病学和人体实验证据,综述了稻米品种、加工方式、烹调方式、储藏和食用温度以及不同食物搭配对米饭餐血糖指数和人体餐后血糖变化的影响。目前证据表明,通过选择合适的大米品种、合理的烹调加工和搭配进食,可以有效调节米饭餐的血糖反应。     

Detection of recombinant DNA from genetically modified papaya

A method using polymerase chain reaction (PCR) was developed to detect the genetically modified (GM) papaya (55-1 line), of which the mandatory safety assessment has not been finished in Japan because of insufficient data. The papaya intrinsic papain gene was used as an internal control. The results of PCR amplification of the papain gene segment indicated that a commercial silica membrane type kit (QIAGEN DNeasy plant mini) was useful for extraction of DNA from papaya fruit, but not for extraction from canned papaya fruit. On the other hand, a commercial ion-exchange type kit (QIAGEN Genomic-tip) provided enough purified DNA for PCR from canned papaya fruit. Compared with the parental line and other commercial non-GM papayas, the DNA from GM papaya fruit provided specific amplification bands in PCR with five primer pairs (Nos. 2-6) including beta-glucuronidase and neomycin phosphotransferase II gene-specific ones. On the other hand, the primer pairs recognizing these genes showed false-positive results when we used DNAs from canned papaya. Therefore, we recommend that the primer pairs (Nos. 5 and 6) recognizing the sequences derived from two different species of organism should be used in order to detect specifically the GM papaya in canned fruits.     

DNA extraction method using a silica-base resin type kit for the detection of genetically modified papaya

Genetically modified (GM) papaya has not yet been approved for importation into, or cultivation in the European Union (EU) and Japan. A DNA extraction method using the Qiagen DNeasy Plant Mini Kit (PM method) and a method using a buffer containing cetyltrimethyl ammonium bromide (CTAB method) have been adopted as the official Japanese methods for detecting GM foods. However, the amounts of DNA extracted from papaya by these methods are very low. Therefore, we investigated an extraction method to obtain a high yield of DNA from raw or freeze-dried fresh papaya using the Promega Wizard DNA Clean-Up Resin System (WCR). The incubation for the extraction was carried out at 58 degrees C without proteinase K for 15 min. The extract was applied to a mini-column, then the column was washed with 80% isopropyl alcohol, and genomic DNA adsorbed on the column was eluted with TE buffer. The WCR method gave a higher yield of genomic DNA, and was simpler and faster than the PM method or CTAB method. In addition, it could be used to extract genomic DNA from fresh papaya at various stages of ripeness. Based on these results, we propose that the present method using WCR is the most practical and useful way to extract genomic DNA for the purpose of detecting GM papaya.     

番木瓜籽中异硫氰酸苄酯抗癌抑菌功能研究进展

番木瓜(Carica Papaya)是一种极具营养价值而被广泛种植的热带水果,其籽中含有苄基硫代葡萄糖苷(Glucosinolate,GS),约占番木瓜重量7%,是果肉加工的废弃物。GS主要存在于细胞空泡,当其接触到芥子酶就会被水解,生成异硫氰酸酯类(Isothiocyanates,ITCs)。ITCs是十字花科植物的次生代谢产物,是一类重要的有机合成中间体,公认具有防癌抗癌功效以及抑菌作用,异硫氰酸苄酯(Benzyl isothiocyanate,BITC)是ITCs中生物学效果最为明显的一种。BITC对许多癌症有明显的抑制作用,可以阻断癌细胞增殖分化;BITC对致病菌有抑制甚至杀死作用,这种抑菌活性可以作用于细菌和霉菌。本文结合国内外相关研究现状,综述BITC在防癌抗癌及抑菌方面的研究进展,为番木瓜籽副产物BITC更深一步的加工以及番木瓜综合利用率的提升提供一定的理论依据。     

木瓜籽油的组成、性质及功能特性研究进展

对木瓜籽油的营养价值、理化性质、生物活性等进行综述,为木瓜籽油的理论研究和产业化开发提供依据。     

番木瓜加工副产物综合利用研究进展

番木瓜是番木瓜科番木瓜属多年生肉质草本植物,具有较高的营养价值和药用价值。其含有丰富的糖类、多酚、番木瓜碱,有机酸等物质,具有抗氧化、降血糖及抑菌等多种功效,用途甚广。番木瓜皮、籽、叶具有多种活性物质,副产物加工具有巨大的经济效益。但目前木瓜副产品较少,利用率较低,造成极大的浪费。本综述整理番木瓜加工过程产生的副产物及其功能活性成分在食品工业中的应用,以期对番木瓜副产物合理应用,减少环境污染提供科学指导。     

番木瓜中生物活性成分的研究进展

综述了番木瓜生物活性成分的研究进展,包括木瓜蛋白酶、糖类、萜类化合物、黄酮类、色素等的研究应用现状,为番木瓜的进一步研究和开发利用提供了理论依据。      

2018年我国稻谷加工科研回顾与展望

为全面深入了解我国稻谷加工科研现状,从成品大米加工、大米制品加工及大米深加工等方面回顾了2018年稻谷加工科研状况。指出在稻谷品质、加工工艺、质量控制、营养米、重组米、专用米等研究方面虽取得较大进展,但仍需进一步加强稻谷加工的科研工作。并提出下一步发展具体建议,以期为稻谷生产、加工、科研以及政策制定等提供参考。     

COMBINED EFFECTS OF ENZYME DOSAGE AND REACTION TIME ON PAPAYA JUICE EXTRACTION WITH THE AID OF PECTIC ENZYMES – A PRELIMINARY REPORT

Pectic enzymes are widely used in the food industry for fruit juice extraction as well as in the clarification of cloudy juices. Our laboratory has been using pectic enzymes produced from a strain of Saccharomyces cerevisiae (ATCC 52712) in different applications including fruit juice extraction. The enzyme was produced in the laboratory by culturing the yeast in papaya juice supplemented with 1% pectin for 6 days. Known amounts of enzyme preparation (0–40 mg protein) were added to a measured weight of papaya mash for varying reaction periods (30–90 min) and the amount of free‐run juice obtained in each treatment compared with a control sample. Treatment of 200 g of papaya mash with different dosages of the pectic enzyme extract resulted in rapid increases in flow rate of free‐run juice. Mash treated with 32 mg of total protein extract with a 30‐min reaction time was the optimum for a maximum rate of juice flow (25 mL/min) when initial rates were measured. There was no significant difference (P > 0.05) between the red‐ and yellow‐fleshed varieties of the papaya used. When juice flow was monitored over 6 min, the treated samples gave a flow rate that was more than twice those of the untreated samples. This biotechnological approach could be adopted to enhance papaya‐juice production by local fruit juice processors when parameters for scale‐up processes are established.     

Effects of Storage Conditions on Quality and Shelf-life of Fresh-cut Melon (Cucumis Melo L.) and Papaya (Carica Papaya L.)

This research were study physical and chemical changes of fresh-cut melon and papaya on different storage and shelf-life evaluation of products. Fresh-cut melon and papaya was kept at the different storage temperature conditions with observed on physical characteristics of texture and color of their flesh and measured of chemical characteristics on water content, sucrose content, acidity, vitamin C, and total carotene. Physical and chemical changes were observed on fresh-cut melon and papaya under different storage conditions.Fresh-cut products stored in lower temperature on ±14-15 °C had optimum shelf-life of 4 days for melon and 3 days for papaya.     

木瓜保健果醋的工艺研究

木瓜营养丰富,且具有良好的保健功能,以木瓜为原料,采用液态发酵法,经过酒精发酵和醋酸发酵,研制出风味独特、营养保健的木瓜醋,对开发木瓜保健调味品具有重要意义。该文对木瓜果汁浸提、酒精发酵、醋酸发酵等主要工艺进行了研究。     

The impact of transgenic papaya (TPY10-4) fruit supplementation on immune responses in ovalbumin-sensitised mice

BACKGROUND: A transgenic papaya line (TPY10‐4) that is resistant to both papaya ringspot virus (PRSV) and papaya leaf distortion mosaic virus (PLDMV) has been developed in Taiwan. This study investigated the immunomodulatory properties of transgenic TPY10‐4 and its native (TCK) papaya fruits using an ovalbumin (OVA)‐sensitised mouse model. Both green and ripe papaya fruits at low (0.2 g powder kg^?1 body weight (BW)) and high (1.6 g powder kg^?1 BW) doses were administered to experimental mice by intragastric gavage for 5 weeks. Changes in serum total immunoglobulin A (IgA), IgE, IgG and IgM levels, OVA‐specific IgE, IgG1 and IgG2a titres and Th1/Th2 cytokine secretions using splenocytes were determined. RESULTS: Transgenic TPY10‐4 or native TCK papaya fruit supplementation did not significantly affect body, visceral organ and relative tissue weights, total IgE antibody levels, OVA‐specific IgE and IgG1 antibody titres or OVA‐stimulated interferon‐γ (IFN‐γ), interleukin‐2 (IL‐2), IL‐4, IL‐5 and IL‐10 secretions using splenocytes. However, transgenic papaya fruits markedly increased serum total IgM levels. CONCLUSION: This study suggests that transgenic TPY10‐4 papaya fruits do not increase the allergenic potential of OVA by oral administration but may have a protective immunity via increasing the serum total IgM level. Copyright © 2010 Society of Chemical Industry