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71.
Plant protein-based adhesives could fundamentally solve the problem of formaldehyde-based adhesive releasing formaldehyde, but enhancing bonding strength and water resistance is a necessary measure to realize practical applications. In this study, the effects of different denaturants on the properties of a hot-pressed peanut meal (HPM)-based adhesive before and after crosslinking were studied. Papain, sodium dodecyl sulfate (SDS), urea and crosslinker-polyamide epichlorohydrin (PAE) were used to prepare HPM-based adhesives. The functional groups, bonding strength, thermal behaviors, mass loss, moisture uptake value, viscosity and fracture surface of adhesive samples were analyzed. As a result, (1) papain was used to break HPM protein (HPMP) into polypeptide chains and to reduce the water resistance. (2) SDS and urea unfold the HPMP molecule and expose internal hydrophobic groups to improve the water resistance of the adhesive. (3) A denser network structure was formed by PAE and HPMP molecules, which significantly improved the bonding strength and water resistance of adhesives. In particular, after SDS denaturation and PAE crosslinking, compared with pure HPM adhesive, the wet shear strength increased by 96.4%, the mass loss and moisture uptake value reduced by 41.4% and 69.4%, and viscosity increased by 30.4%. This work provided an essential guide to design and prepare HPM-based adhesives. 相似文献
72.
水稻 (OryzasativaL .)曲阜香系 10 3成熟胚在MS1培养基上诱导培养 ,初始愈伤组织为深黄色、瘤状 ,非松脆类型 .当在MS2 培养基上继代培养 ,经 3~ 4月初始愈伤组织转变为浅黄色、小颗粒状 ,松脆型胚性愈伤组织 .将胚性愈伤组织置于液体培养基中悬浮培养 ,经 4月多可得分散性好、生长快的胚性悬浮细胞系 . 相似文献
73.
牛体外受精胚胎在成份确定培养液内的发育 总被引:1,自引:1,他引:1
将牛体外受精胚胎培养于化学成份确定的 SOF+PVA的培养系统内 ,观察了不同PVA浓度对胚胎体外发育的影响 .结果在 1 mg/ml、3mg/ml和 5mg/ml的 PVA浓度条件下 ,囊胚的发育率分别为 2 7.5% a、1 9.1 % a和 4 .3% b( a>b,P<0 .0 1 ) .将体外受精胚胎分别培养于 M1 99+输卵管上皮细胞、SOF+BSA和 SOF+PVA的三种培养系统内 ,囊胚的发育率分别为 2 0 .4 %、2 9.0 %和 2 7.5% ,结果表明本研究确立的化学成份确定的体外培养系统可以用于牛体外受精胚胎的发育培养 . 相似文献
74.
When peanuts germinate, bioactive compounds such as resveratrol (RES), γ-aminobutyric acid (GABA), isoflavones, and polyphenol compounds are generated. Peanut kernels were germinated in the dark for two days, and stimuli including soaking liquid, rice koji, high-pressure processing (HPP), and ultrasonic treatment were tested for their ability to activate the defense mechanisms of peanut kernels, thus increasing their bioactive compound content. The results of this study indicate that no RES was detected in ungerminated peanuts, and only 5.58 μg/g of GABA was present, while unstimulated germinated peanuts contained 4.03 µg/g of RES and 258.83 μg/g of GABA. The RES content of the germinated peanuts increased to 13.64 μg/g after soaking in 0.2% phenylalanine solution, whereas a higher GABA content of 651.51 μg/g was observed after the peanuts were soaked in 0.2% glutamate. Soaking peanuts in 5% rice koji produced the highest RES and GABA contents (28.83 µg/g and 506.34 μg/g, respectively). Meanwhile, the RES and GABA contents of HPP-treated germinated peanuts (i.e., treated with HPP at 100 MPa for 10 min) increased to 7.66 μg/g and 497.09 μg/g, respectively, whereas those of ultrasonic-treated germinated peanuts (for 20 min) increased to 13.02 μg/g and 318.71 μg/g, respectively. After soaking peanuts in 0.5% rice koji, followed by HPP treatment at 100 MPa for 10 min, the RES and GABA contents of the germinated peanuts increased to 37.78 μg/g and 1196.98 μg/g, while the RES and GABA contents of the germinated peanuts treated with rice koji followed by ultrasonic treatment for 20 min increased to 46.53 μg/g and 974.52 μg/g, respectively. The flavonoid and polyphenol contents of the germinated peanuts also increased after exposure to various external stimuli, improving their DPPH free radical-scavenging ability and showing the good potential of germinated peanuts as functional products. 相似文献
75.
Wanqing Yao Ruanshan Liu Fengru Zhang Shuang Li Xiaoxia Huang Hongwei Guo Mengxia Peng Guohua Zhong 《Molecules (Basel, Switzerland)》2022,27(19)
Aflatioxin B1 (AFB1) has been recognized by the International Agency of Research on Cancer as a group 1 carcinogen in animals and humans. A fast, batch, and real-time control and no chemical pollution method was developed for the discrimination and quantification prediction of AFB1-infected peanuts by applying Fourier transform near-infrared (FT-NIR) coupled with chemometrics. Initially, the near-infrared transmission (NIRT) and diffuse reflection (NIRR) modules were applied to collect spectra of the samples. The principal component analysis (PCA) method was employed to extract the characteristic wavelength, followed by different preprocessing methods (seven methods) to build an effective linear discriminant analysis (LDA) classification and partial least squares (PLS) quantification models. The results showed that, for both the NIRT or NIRR modules, the LDA classification models satisfactorily distinguished peanuts infected with AFB1 or from those not infected, with external validation showing a 100% correct identification rate and a 0% misjudgment rate. In addition, combined with the concentration of AFB1 in peanuts determined by enzyme-linked immunoassay assay, the best partial least squares (PLS) models were established, with a combination of the first derivative and the Norris derivative filter smoothing pretreatment (Rc2 = 0.937 and 0.984, RMSECV = 3.92% and 2.22%, RPD = 3.98 and 7.91 for NIRR and NIRT, respectively). The correlation coefficient between the predicted value and the reference value in the external verification was 0.998 and 0.917, respectively. This study highlights that both spectral acquisition modules meet the requirements of online, rapid, and accurate identification of peanut AFB1 infection in the early stages. 相似文献
76.
77.
对与花生油质量安全有关的脂肪酸组成及黄曲霉毒素B1、苯并(a)芘、3-氯丙醇酯等危害成分相关的法规标准以及分析检测的进展进行评述.并对黄曲霉毒素B1、苯并(a)芘、3-氯丙醇酯、氧化产物等危害成分的脱除方法进行评述. 相似文献
78.
共聚焦激光扫描显微术研究天花粉蛋白对小鼠胚胎细胞的作用机制 总被引:2,自引:0,他引:2
天花粉蛋白是从中草药Ku楼根中根中取的一种核糖体失活蛋白,具有致流产、抗肿瘤和抗HIV功能。本文应用共聚焦激光扫描显微术结合特异性荧光探针2',7'-二氯荧光黄双乙酸酯和Fluo-3AM,观察了天花粉蛋白作用于小鼠胚胎细胞过程中活性氧自由基和细胞内钙离子浓度的变化。实验结果表明,天花粉蛋白能诱导小鼠胚胎细胞钙浓度升高和产生活性氧自由基,并且天花粉蛋白能有效抑制小鼠胚胎细胞的分裂,为天花粉蛋白的致流产提出了新的机制。 相似文献
79.
Identification of chemical ingredients of peanut stems and leaves extracts using UPLC‐QTOF‐MS coupled with novel informatics UNIFI platform 下载免费PDF全文
Lei Deng Ai‐Min Shi Hong‐Zhi Liu Naren Meruva Li Liu Hui Hu Ying Yang Chun Huang Peng Li Qiang Wang 《Journal of mass spectrometry : JMS》2016,51(12):1157-1167
Peanut stems and leaves have been used traditionally as both herbal medicines and special food in Asia. In this study, the main functional compounds of peanut stems and leaves extracts were identified using UPLC separation coupled to high resolution mass spectrometry (QTOF‐MS), and a traditional medicine library. Three different extraction solvents (ethyl acetate, petroleum ether and n‐butanol) were evaluated to prepare the extracts of peanut stems and leaves. A total of 283 chemical compounds were identified in peanut stems and leaves extracts, of which 207 compounds are tentatively new identifications in Genus Arachis. The integration of data acquisition and processing with the traditional medicine library provides a simple, efficient process to effectively facilitate the identification of chemical ingredients in complex natural product extracts. The integrated workflow for separation, detection and identification of functional compounds in natural products using UPLC/QTOF‐MS greatly improves productivity for development of traditional herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
80.
向日葵未成熟胚组织培养及再生芽的研究 总被引:1,自引:0,他引:1
以89B1、PR29、HA300、RHA265、RHA266、JK6、JK8、龙葵杂八种基因型向日葵为材料,对未成熟胚的萌动、愈伤组织的诱导、分化及再生苗的培养和移栽等方面进行了研究.结果表明:授粉后10~12d的胚分化频率在MS 0.03mg/L,IAA 1.2mg/L 6-BA的培养基上最高,可达70%以上。 相似文献