基于曲线拟合的形态相似鹅膏菌的傅里叶变换红外光谱研究

利用傅里叶变换红外光谱仪测试了形态相似的灰疣鹅膏菌、灰绒鹅膏菌和灰褶鹅膏菌的光谱,结果显示,它们的傅里叶变换红外光谱主要由蛋白质和多糖的振动吸收带组成,其蛋白质的吸收频率略有差。选择酰胺I带(中心频率1647cm-1)进行傅里叶自去卷积和曲线拟合处理后3种鹅膏菌中蛋白质在酰胺I带的吸收峰都由12个子峰叠加而成,其中在无序(1650cm-1)、α螺旋(1658cm-1)和β转角结构(1666cm-1)的振动吸收峰上,灰褶鹅膏菌吸收峰的面积百分比分别是20.98%、4.47%和17.14%,明显地区别于其它两种鹅膏菌(灰疣鹅膏菌:10.26%、12.58%和7.71%;灰绒鹅膏菌:14.33%、9.76%和8.83%)。在1683cm-1处的β转角吸收峰上,灰绒鹅膏菌吸收峰的面积百分比是1.92%,明显小于其它两种鹅膏菌(灰疣鹅膏菌:8.03%;灰褶鹅膏菌:6.65%)。研究表明:傅里叶变换红外光谱技术能提供大型真菌所含蛋白质二级结构信息。     

Characterization of Antioxidant Activity of Momordica Charantia Fruit by Infrared-Based Fingerprinting

Momordica charantia is widely consumed edible fruit. The food and pharmaceutical industries use it as a natural antioxidant. However, the quality control of M. charantia-based medicinal products is questionable due to the complexity of metabolites in this fruit. Hence, this study has developed a statistical model in predicting the antioxidant value through the 2, 2-diphenyl-1 picrylhydrazyl radical scavenging activity and ferric reducing antioxidant power based on infrared spectroscopy with attenuated total reflectance. This technique was reliably used for quality control. Six ethanol extracts (0, 20, 40, 60, 80, and 100% in water) of this plant’s fruit were prepared. The radical scavenging and ferric reducing antioxidant power activities were measured and the chemical profiling of the extracts was fingerprinted by infrared spectroscopy between 4,000 and 600?cm^?1 at a resolution of 4?cm^?1. Statistical analysis was developed by correlating the bioactivity and infrared spectra of each extract using orthogonal partial least square discriminant analysis. The C–N, C?O, C–O, C–H, and OH infrared signals were positively correlated with biological activity. The antioxidant activity of the fruit of M. charantia may be due to the presence of several antioxidants that work synergistically.     

近红外光谱法同时测定银杏提取液中总黄酮和总内酯含量

采用傅里叶变换近红外透射光谱和偏最小二乘法,对银杏提取液中总黄酮和总内酯的含量进行了定量测定。所建立的数学模型对校正集样本的银杏总黄酮和总内酯复相关系数(MR)分别为O．998和o．986;对预测集样本的银杏总黄酮和总内酯复相关系数分别为0．983和0．971,标准回收率分别为95．71％～103．3％和95.29％～104.6％,相对标准偏差(RSD)分别为2．44％和3．19％。结果表明,近红外光谱测定银杏提取液中总黄酮和总内酯含量具有快速、准确的优点,有望应用于银杏提取过程的中间控制和大批量产品的检测。     

热解/红外光谱联用技术用于热解反应的快速检测

详细介绍了快速热解装置CDS2000／红外联用仪(Py／FTIR)的特点。带有样品的热解探头插入并固定在接口装置上，接口装置可直接置于FTIR的光路中，对热解产物进行直接、快速检测，并且可分析重质热解产物。CDS2000热丝裂解器具有极快的升温速度，升温速度从0．01℃／min到20000℃／s，可以有效避免热解过程中的二次反应，有助于推断结构和热解机理；另外，本文对CDS2000／FTIR热解／红外联用仪使用过程中的有关参数进行了分析，如分辨率的选择。本文应用CDS2000／FTIR联用仪对PVC、生物质和模型化合物进行了热解实验，取得了满意的结果。     

Anthocyanins HPLC-DAD and MS Characterization,Total Phenolics,and Antioxidant Activity of Some Berries Extracts

Extracts of indigenous wild blackberries, mulberries, bilberries, and blackthorns were analyzed for anthocyanin composition, anthocyanin content, total phenolics, and antioxidant capacity. Anthocyanins extraction with acidified methanol in ultrasonic condition (59 kHz, 60 min., 25°C) was carried out. The extracts were analyzed by high-performance liquid chromatography (HPLC) using a Dionex Ultimate 3000 apparatus equipped with photodiode array detector for qualitative characterization of the anthocyanins. The chromatograms revealed the presence of a large number of anthocyanins in fruits extracts: blackberries, 4 compounds; mulberries, 3 compounds; bilberries, 18 compounds; and blackthorns, 5 compounds. The most abundant anthocyanins were cyanidin-3-glucoside in blackberry, mulberry, and bilberry, and cyanidin-3-rutinoside in blackthorn extract. Structural information about anthocyanins was obtained by using a mass spectrometric method based on fully automated chip-nanoelectrospray ionization (nanoESI) high capacity ion trap (HCT). Anthocyanin content was quantified by the pH differential method and total phenolics were determined by Folin-Ciocalteu method. A Jasco V 530 UV-VIS spectrophotometer was used for absorbance measurements. The free radical scavenging activity of the berries extracts was performed by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The reduction of DPPH was followed by a spectrophotometric method. Also, a correlation of the antioxidant capacities of the extracts with their anthocyanin content and total phenolics was attempted.     

傅里叶变换红外光谱和傅里叶变换拉曼光谱法无损鉴别药材的真伪

利用傅里叶变换红外（FT-IR）和近红外傅里叶变换拉曼（NIR FT-aman）光谱法对大黄（西宁大黄）与伪品大黄（华北大黄、山大黄、水根大黄）进行了无损快速的鉴别。结果表明：尽管正品大黄与伪品大黄差别较小，有大部分的化学成分有很大的相同之处，但在红外、拉曼谱图中各自的特征峰较突出，根据谱峰的强度和位置可容易地将它们区别开来。红外和拉曼光谱法相互印证，相互补充，具有快速、准确、操作简单、重复性好、不需对样品进行分离提取，可直接鉴别等特点。     

Selective detection of the structural changes upon photoreactions of several redox cofactors in photosystem II by means of light-induced ATR-FTIR difference spectroscopy

Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy was applied for the first time to detect the structural changes upon photoreactions of redox cofactors in photosystem II (PSII). The PSII-enriched membranes from spinach were adsorbed on the surface of a silicon prism, and FTIR measurements of various redox cofactors were performed for the same sample but under different conditions by exchanging buffers in a flow cell. Light-induced FTIR difference spectra upon redox reactions of the oxygen-evolving Mn cluster, the primary quinone electron acceptor QA, the redox-active tyrosine YD, the primary electron acceptor pheophytin, and the primary electron donor chlorophyll P680 were successively recorded in buffers including different redox reagents and inhibitors. All of these cofactors remained active in the PSII membranes on the silicon surface, and the resultant spectra were basically identical to those previously recorded by the conventional transmission method. These ATR-FTIR measurements enable accurate comparison between reactions of different active sites in a single PSII sample. The present results demonstrated that the ATR-FTIR spectroscopy is a useful technique for investigation of the reaction mechanism of PSII.     

二维相关红外光谱法与阿胶的真伪鉴别

采用傅里叶变换红外光谱法(FT-IR)和二维相关红外光谱技术(2D-IR)对几种阿胶进行了真伪鉴别。实验结果表明,伪品阿胶和黄明胶与标本东阿阿胶的谱图较为相似,尤其是黄明胶与阿胶极其相似,仅仅在1648cm^-1的酰胺I带的吸收峰和东阿阿胶有9个波数的区别;不同批次和厂家的正品阿胶的红外光谱图更为相似,难以区分开,借助于二维相关红外光谱法,获取了物质的微观结构信息,提高了谱图的分辨率,几种真品阿胶得到了直观有效的鉴别。     

HATR-FTIR-排序法识别中药材紫花地丁及其伪品的研究

采用水平衰减全反射傅里叶变换红外光谱(HATR-FTIR)法测定了紫花地丁及其伪品如白花地丁、犁头草、辽宁堇菜及匍伏堇的根木质部和茎外表皮部的傅里叶变换红外光谱,采用主成分分析法(PCA)比较了正伪品之间的差异程度。结果表明：基于傅里叶变换红外光谱的主成分分析在反映同科同属不同种植物化学组成差异程度上具有应用价值。     

傅里叶变换红外光谱对食道癌及相应正常组织的研究

研究了9例食道癌及相应正常组织的红外光谱，从光谱参数（形状、频率、强度等）方面进行了分析。结果表明：癌组织样品与政党组织样品存在明显的光谱上的差异。着重讨论了核酸中磷酸二酯基团（PO2^-)对称和反对称伸缩振动、膜脂中的碳氢基团（CH3，CH2）的伸缩及弯曲振动、蛋白质中C－O基团的伸缩振动峰的变化。从氢键角度以及膜脂碳氢链排列及构象变化角度分析了变化的原因。     

36种灵芝产品傅里叶变换红外光谱快速鉴别研究

利用傅里叶变换红外光谱法（FTIR）无损快速鉴别了36种灵芝类产品。灵芝、孢子粉和菌丝体的红外谱图差别较显著;不同厂家所生产的灵芝产品由于所选用灵芝的产地不同、所用辅料的种类以及辅料所添加的多少不同,均引起了谱图的相对峰强度和波数位置的改变。结果表明：36种灵芝产品均可以根据红外的特征谱图进行分类鉴别。该方法快速、不需对灵芝产品进行分离提取。     

高灰煤中矿物质及碳结构的振动光谱分析

利用傅里叶变换红外光谱(FT-IR)、拉曼光谱和X射线衍射(XRD),分析了广西合山煤(GX)和平顶山煤(PD)及其酸洗煤的矿物质组分和碳结构。FT-IR谱图显示,GX和PD原煤的高岭石含量最为丰富,其次是石英和方解石,由二阶导数红外谱图发现,煤中还存在云母、蛇纹石、石膏和碱性长石。此外,从FT-IR谱图出现的三个层间水OH伸缩振动峰(3 695、3 651和3 619 cm^-1)判断煤中高岭石的结晶度不高。酸洗煤的FT-IR和XRD分别显示出清晰的芳香C=C官能团峰(1 600 cm^-1)和微晶碳(002)衍射峰;原煤的FT-IR和XRD都表明,矿物质完全掩盖了碳的信息。尽管如此,原煤及酸洗煤的拉曼谱图显示出清晰的缺陷碳峰(D峰)和石墨碳峰(G峰),而矿物质的信息完全被信号更强的碳峰掩盖。酸洗处理对煤的碳结构有较弱的影响,酸洗煤的碳结构有序度略低于原煤。     

傅里叶变换红外光谱诊断地中海贫血症

为建立简单快速的地中海贫血诊断方法,本研究探讨了以傅里叶变换红外光谱结合水平衰减全反射(FTIR-HATR)技术在地中海贫血诊断中的制样方法及光谱的数据处理方法.在制样预处理中,通过对样品进行稀释并干燥成膜消除水分子对光谱吸收干扰,保持ATR光谱中各波长对样品的穿透深度一致.结果表明,当1652 cm-1吸收度小于1.5时(即透射率T小于4%时),各波峰强度与血红蛋白浓度呈良好的线性关系(r>0.995)及实验重复性(RSD<4%).在数据处理上,改进的相对强度方法用于800～1780 cm-1和2480～3600 cm-1区间的分析.通过与常规的傅里叶去卷积谱及差谱方法相比,本方法可消除样品浓度所带来的影响因素,灵敏地揭示群体数据中组分与结构在不同组间的显著差异,如1638 cm-1处重叠的蛋白二级结构峰,1172 cm-1、1440 cm-1表征脂类物质的吸收峰,1064 cm-1表征磷酸化合物峰位及表征SH的2553 cm-1附近的吸收峰在正常组与地中海贫血组间存在显著差异.从而避免了几个峰位的相对强度所反映的信息不足及选择参比峰的困扰,对揭示整体的差异变化规律有着重要的作用.     

Characterization of new natural cellulosic fiber from the Ipomoea staphylina plant

Natural fibers extracted from plants play a major role as reinforcement in polymer composite materials due to their superior properties. This work aims to comprehensively characterize the physical and chemical properties of Ipomoea staphylina fibers (ISFs), which are extracted from the stem of the Ipomoea staphylina plant. The ISFs show cellulose content (72.76 wt%), hemicelluloses content (13.6 wt%), density (1401 kg cm^?3), and tensile strength of 173–658 MPa with a strain rate of 2.03–6.63%. The thermal stability of ISFs illustrate that the fibers are stable up to a temperature of 311°C with kinetic activation energy of 99.82 kJ mol^?1.     

Antioxidant and Antimicrobial Activities of Thai Edible Plant Extracts Prepared Using Different Extraction Techniques

This study investigated the antioxidant and antimicrobial activities of six Thai edible plant leaf extracts, including Cashew (CN), Chamuang (CM), Monpu (MP), Thurianthet (TT), Kradon (KD) and Pakliang (PL), extracted using ethanol extraction (EE), microwave-assisted extraction (MAE), and ultrasonic-assisted extraction (UAE). The leaf extracts were characterized for percentage yield, total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and-ferric reducing antioxidant power (FRAP) activity, and antimicrobial activity against spoilage. MAE produced the highest percentage yields, among which MAE-extracted MP exhibited the highest yield. Furthermore, the highest TPC and TFC were obtained for MAE, with MAE-extracted KD and CN showing the highest TPC and TFC, respectively, among the samples. The highest DPPH and FRAP values were seen in MAE-processed CN, KD, and MP extracts. The inhibition zone of pathogenic bacteria, minimum inhibitory concentration, and minimum bacterial concentration were determined in all samples except TT. These findings indicate that, compared to EE and UAE, MAE improved the antioxidant and antimicrobial efficacy of the leaf extracts. The aforementioned extracts could be employed as natural food additives to prevent chemical and microbial spoilage of foods.     

红外光谱法对肉苁蓉径向不同部位的分析与评价

采用傅里叶变换红外光谱、二阶导数谱和二维相关红外光谱技术对肉苁蓉由表及里3个部位的药材粉末及其水提物和醇提物进行了分析与评价研究.结果表明,肉苁蓉不同部位的一维光谱非常相似,三者相似系数分别为0.9605,0.944和0.976;二阶导数谱中峰位和峰强的差异明显.1430～1700 cm-1范围内的二维相关谱中皮部自动峰有3个,而中部及髓部均为4个,更直观的反映出三者的差异.不同部位水提物和醇提物的分析结果进一步明确了肉苁蓉皮部芳香类、环烯醚萜类及糖苷类物质与中部和髓部存在明显不同,而髓部的水溶性多糖、半乳糖醇和苯乙醇苷类物质均高于其它部位.可见红外光谱法结合二维相关红外光谱技术为同种药材不同部位的细微差异分析和评价提供了一种快速、全面和客观的方法和手段.     

6种燕窝的傅里叶变换红外光谱法原性状快速鉴别

首次利用微钻石ATR探头傅里叶变换红外光谱法（FTIR）无损快速鉴别了6种燕窝。结果表明：印尼燕、越南燕、马来西亚燕、泰国血燕、菲律宾草燕和香港市售燕窝均有自己的红外特征谱,据谱图吸收峰的波数位置和相对峰强度的差异可达到燕窝类同和伪品和鉴别。该方法快速、简便、可靠。     

Characterization of nano FeIII-tannic acid modified polyacrylate in controlled-release coated urea by Fourier transform infrared photoacoustic spectroscopy and laser-induced breakdown spectroscopy

Polyacrylate polymer (PA) has been widely applied in coating products for decades. Recently, it has been used in controlled-release fertilizers. Nano Fe^III-tannic acid modified PA (PA-Fe) provides a better nutrient controlled release performance than conventional PA. In this work, a preliminary database of molecular and elemental information about the polymer was obtained using FTIR-PAS (Fourier transform infrared photoacoustic spectroscopy) and LIBS (laser-induced breakdown spectroscopy), respectively. The PA-Fe polymer contained more hydrophobic groups (–CH₃) and fewer hydrophilic groups (–COOR, –COOH) than PA. More elements were detected for PA-Fe than PA. LIBS was useful to identify and classify PA and PA-Fe samples using principal component analysis. The combination of spectroscopic results and a film formation process model explained the lower nutrient release rate of PA-Fe. These results showed the strong analytical capabilities of FTIR-PAS combined with LIBS for identifying and characterizing modified PA.     

Physicochemical properties of new cellulosic fibers from the bark of Acacia arabica

With the growing environmental consciousness toward carbon emissions, natural fibers are the best alternative and act as a substitute for synthetic fibers due to their potential properties. New cellulosic fibers were identified from Acacia arabica bark. This study aimed at understanding the characteristics of Acacia arabica fibers (AAFs) extracted from the bark of the A. arabica, and its physicochemical properties were examined by thermal stability analyses, X-ray diffraction, chemical constitutions, and Fourier transform infrared spectroscopy analysis. Cellulose content (68.1 wt%), density (1028 kg m^?3), and crystallinity index (51.72%) properties were identified.     

Classification of the Biopolymer Sodium Pentosan Polysulfate by Infrared Spectroscopy

Summary Sodium pentosan polysulfate (NaPPS) is a glycosaminoglycan that is of increasing interest due to its medical properties. It has been investigated for the treatment of osteoarthritis, HIV and Prion based diseases. This work describes an investigation into the application of infrared spectroscopy (IR) for the differentiation between sources of NaPPS. Multivariate techniques such as principle components analysis were applied to detect differences between the IR and near IR (NIR) spectra and to classify the biopolymers based on their manufacturer. This study compared two samples of NaPPS from different manufacturers. Principle components analysis (PCA) together with soft independent modeling of class analogies (SIMCA) was used to successfully classify the different samples. Clear differentiation between all batches was achieved using PCA and class distances using first derivative spectra (500–1800 cm^–1).Presented at: International Symposium on Separation and Characterization of Natural and Synthetic Macromolecules, Amsterdam, The Netherlands, February 5–7, 2003