Rapid identification and differential markers of Curcumae Radix decoction pieces of different sources based on Heracles Neo ultra-fast gas phase electronic nose / 中国中药杂志

Since Curcumae Radix decoction pieces have multiple sources, it is difficult to distinguish depending on traditional cha-racters, and the mixed use of multi-source Curcumae Radix will affect its clinical efficacy. Heracles Neo ultra-fast gas phase electronic nose was used in this study to quickly identify and analyze the odor components of 40 batches of Curcumae Radix samples from Sichuan, Zhejiang, and Guangxi. Based on the odor fingerprints established for Curcumae Radix decoction pieces of multiple sources, the odor components was identified and analyzed, and the chromatographic peaks were processed and analyzed to establish a rapid identification method. Principal component analysis(PCA), discriminant factor analysis(DFA), and soft independent modeling cluster analysis(SIMCA) were constructed for verification. At the same time, one-way analysis of variance(ANOVA) combined with variable importance in projection(VIP) was employed to screen out the odor components with P<0.05 and VIP>1, and 13 odor components such as β-caryophyllene and limonene were hypothesized as the odor differential markers of Curcumae Radix decoction pieces of diffe-rent sources. The results showed that Heracles Neo ultra-fast gas phase electronic nose can well analyze the odor characteristics and rapidly and accurately discriminate Curcumae Radix decoction pieces of different sources. It can be applied to the quality control(e.g., online detection) in the production of Curcumae Radix decoction pieces. This study provides a new method and idea for the rapid identification and quality control of Curcumae Radix decoction pieces.

Establishment of a fast discriminant model with electronic nose for Polygonati Rhizoma mildew based on odor variation / 中国中药杂志

The odor fingerprint of Pollygonati Rhizoma samples with different mildewing degrees was analyzed and the relationship between the odor variation and the mildewing degree was explored. A fast discriminant model was established according to the response intensity of electronic nose. The α-FOX3000 electronic nose was applied to analyze the odor fingerprint of Pollygonati Rhizoma samples with different mildewing degrees and the radar map was used to analyze the main contributors among the volatile organic compounds. The feature data were processed and analyzed by partial least squares discriminant analysis(PLS-DA), K-nearest neighbor(KNN), sequential minimal optimization(SMO), random forest(RF) and naive Bayes(NB), respectively. According to the radar map of the electronic nose, the response values of three sensors, namely T70/2, T30/1, and P10/2, increased with the mildewing, indicating that the Pollygonati Rhizoma produced alkanes and aromatic compounds after the mildewing. According to PLS-DA model, Pollygonati Rhizoma samples of three mildewing degrees could be well distinguished in three areas. Afterwards, the variable importance analysis of the sensors was carried out and then five sensors that contributed a lot to the classification were screened out: T70/2, T30/1, PA/2, P10/1 and P40/1. The classification accuracy of all the four models(KNN, SMO, RF, and NB) was above 90%, and KNN was most accurate(accuracy: 97.2%). Different volatile organic compounds were produced after the mildewing of Pollygonati Rhizoma, and they could be detected by electronic nose, which laid a foundation for the establishment of a rapid discrimination model for mildewed Pollygonati Rhizoma. This paper shed lights on further research on change pattern and quick detection of volatile organic compounds in moldy Chinese herbal medicines.

Application progress on taste evaluation methods for oral preparations / 中国中药杂志

Taste is an important factor affecting the medicinal properties of oral preparations and patient compliance with medication, and also an important evaluation index for oral preparation design and clinical application. How to characterize the taste objectively, accurately, simply, and efficiently is a bottleneck problem that restricts the taste design, development, and utilization of oral preparations. At present, the commonly used taste assessment methods for oral preparations are traditional human taste panel, electronic tongue, animal preference test, in vitro release study, and electrophysiological test. The traditional human taste panel is the first choice for taste evaluation, but it is limited by poor subjectivity and reproducibility. Therefore, despite some limitations, the other four taste assessment methods have been applied in the pharmaceutical industry as auxiliary methods. This study reviewed the detection principles, applicability, advantages, and disadvantages of the above methods to provide references for the taste correction research and taste assessment of oral preparations, improve patient compliance and the competitiveness of oral preparation products in the industry, and promote the development of oral preparation technologies.

Flavorand taste change rules of Sophora Flavescentis Radix processed using ancient classical method:an exploration based on intelligent sensory analysis / 中国中药杂志

This study was designed to investigate the flavor and taste change rules of Sophora Flavescentis Radix processed using the ancient classical method documented in Master Lei's Discourse on Medicinal Processing(Lei Gong Pao Zhi Lun). The Sophora Flavescentis Radix pieces and the corresponding test samples in each processing stage were first prepared based on the processing method for Sophora Flavescentis Radix recorded in Master Lei's Discourse on Medicinal Processing(Lei Gong Pao Zhi Lun). Then the flavors and tastes of Sophora Flavescentis Radix test samples undergoing the soaking in rice-washed water, washing with clean water, and steaming for different time were compared with the electronic nose and tongue. The results showed that in the preparation of Sophora Flavescentis Radix with the ancient method, such processes as soaking in rice-washed water and washing with clean water had no significant influences on the flavor, which, however, was weakened by steaming. In terms of the taste, soaking with rice-washed water enhanced the bitter taste of Sophora Flavescentis Radix, which remained unchanged after being washed with the clean water. The steaming would also diminish the bitter taste, making it taste similar to the original Sophora Flavescentis Radix medicinal materials. During the steaming for six to eight hours, the flavor did not vary significantly over time, while the bitter taste was first weakened and then intensified. The bitter taste of Sophora Flavescentis Radix steamed for six hours was similar to that steamed for eight hours. In addition, the differences in flavor and taste between Sophora Flavescentis Radix pieces processed by the ancient method in Master Lei's Discourse on Medicinal Processing(Lei Gong Pao Zhi Lun)and those by the modern method in the 2020 edition of Chinese Pharmacopoeia were analyzed. The findings demonstrated that the flavor of Sophora Flavescentis Radix pieces prepared by the ancient method was weaker than that by the modern method, whereas the bitter taste showed the opposite trend. The exploration on the flavor and taste change rules of Sophora Flavescentis Radix in its preparation by the ancient classical method and the differences in flavor and taste between Sophora Flavescentis Radix decoction pieces prepared by ancient and modern methods will lay a foundation for further elucidation of the scientific connotation of the ancient processing method and the medication principles of Sophora Flavescentis Radix in both ancient and modern times.

High-speed identification of odor changes and substance basis of Myristicae Semen mildew by electronic nose and HS-GC-MS / 中国中药杂志

This study adopted headspace-gas chromatography-mass spectrometry(HS-GC-MS) and electronic nose to detect volatile components from Myristicae Semen samples with varying degrees of mildew, aiming at rapidly identifying odor changes and substance basis of Myristicae Semen mildew. The experimental data were analyzed by electronic nose and principal component analysis(PCA). The results showed that Myristicae Semen samples were divided into the following three categories by electronic nose and PCA: mildew-free samples, slightly mildewy samples, and mildewy samples. Myristicae Semen samples with different degrees of mildew greatly varied in volatile components. The volatile components in the samples were qualitatively and quantitatively detected by HS-GC-MS, and 59 compounds were obtained. There were significant differences in the composition and content in Myristicae Semen samples with different degrees of mildew. The PCA results were the same as those by electronic nose. Among them, 3-crene, D-limonene, and other terpenes were important indicators for the identification of mildew. Bicyclo[3.1.0]hexane, 4-methylene-1-(1-methylethyl)-, terpinen-4-ol, and other alcohols were key substances to distinguish the degree of mildew. In the later stage of mildew, Myristicae Semen produced a small amount of hydroxyl and aldehyde compounds such as acetaldehyde, 2-methyl-propionaldehyde, 2-methyl-butyraldehyde, and formic acid, which were deduced as the material basis of the mildew. The results are expected to provide a basis for the rapid identification of Myristicae Semen with different degrees of mildew, odor changes, and the substance basis of mildew.

Electronic Nose, Tongue and Eye: Their Usefulness for the Food Industry / Nariz, Lengua y Ojo Electrónico: Su Utilidad para la Industria Alimentaria

Background: The electronic nose, tongue, and eye are futuristic technologies that have been used for many years; they have been gaining market in different types of industries and can increasingly be found in the food area; their function is to determine sensory characteristics (smell, aroma, and flavor) and objective visuals, without the subjectivity that can be represented by sensory analysis by people (the study that can complement the analysis of machines, without being exclusive). Objectives: Find the main generalities of these mechanisms, their sensors, software, mechanism of action, and applications within the food industry. Methods: A search was carried out in the main databases of indexed articles, with terms that allowed collecting the necessary information, and 89 articles were used that met different inclusion criteria. Results: The main outcomes were to understand the operation of each of these technologies, what their main components are, and how they can be linked in the beer, wine, oil, fruit, vegetable, dairy, etc. industry to determine their quality, safety, and fraud. Conclusions: The use of electronic nose, tongue, and eye is found in more food industries every day. Its technology continues to evolve; the future of sensory analysis will undoubtedly apply these mechanisms due to the reliability, speed, and reproducibility of the results.

Antecedentes: La nariz, lengua y ojo electrónico son tecnologías futuristas que se vienen empleando hace muchos años, han ido ganando mercado en diferentes tipos de industria y cada vez más se lo puede encontrar en el área de alimentos, su función es el de determinar características sensoriales (olor, aroma y sabor) y visuales objetivas, sin la subjetividad que puede representar el análisis sensorial por parte de personas (análisis que puede complementar al análisis de las máquinas, sin ser excluyente). Objetivo: El objetivo de esta investigación fue encontrar las principales generalidades de estos mecanismos, sus sensores, software, mecanismo de acción y aplicaciones dentro de la industria de los alimentos. Métodos Se realizó una búsqueda en las principales bases de datos de artículos indexados, con términos que permitieran recabar la información necesaria, y se utilizaron 89 artículos que cumplieron distintos criterios de inclusión. Resultados: Los principales resultados fueron entender el funcionamiento de cada una de estas tecnologías, cuáles son sus principales componentes y cómo pueden estar ligados en la industria de la cerveza, vino, aceites, frutas, hortalizas, lácteos, etc., para determinar su calidad, inocuidad y fraude. Conclusión: El uso de nariz, lengua y ojo electrónico cada día se encuentra en más industrias de alimentos y su tecnología sigue evolucionando, el futuro del análisis sensorial será sin duda la aplicación de estos mecanismos por la fiabilidad, rapidez y reproducibilidad de los resultados.

Identification of curcumin content in raw and vinegar-processed rhizomes of Curcuma kwangsiensis based on electronic nose combined with back propagation neural network / 中国中药杂志

This study aimed to establish a rapid and accurate method for identification of raw and vinegar-processed rhizomes of Curcuma kwangsiensis, in order to predict the content of curcumin compounds for scientific evaluation. A complete set of bionics recognition mode was adopted. The digital odor signal of raw and vinegar-processed rhizomes of Curcuma kwangsiensis were obtained by e-nose, and analyzed by back propagation(BP) neural network algorithm, with the accuracy, the sensitivity and specificity in discriminant model, correlation coefficient as well as the mean square error in regression model as the evaluation indexes. The experimental results showed that the three indexes of the e-nose signal discrimination model established by the neural network algorithm were 100% in training set, correction set and prediction set, which were obviously better than the traditional decision tree, naive bayes, support vector machine, K nearest neighbor and boost classification, and could accurately differentiate the raw and vinegar products. Correlation coefficient and mean square error of the regression model in prediction set were 0.974 8 and 0.117 5 respectively, and could well predict curcumin compounds content in Curcuma kwangsiensis, and demonstrate the superiority of the simulation biometrics model in the analysis of traditional Chinese medicine. By BP neural network algorithm, e-nose odor fingerprint could quickly, conveniently and accurately realize the discrimination and regression, which suggested that more bionics information acquisition and identification patterns could be combined in the field of traditional Chinese medicine, so as to provide ideas and methods for the rapid evaluation and stan-dardization of the quality of traditional Chinese medicine.

Discrimination of Armeniacae Semen Amarum from different processed products and various rancidness degrees by electronic nose and support vector machine / 中国中药杂志

This study was aimed to develop a simple, rapid and reliable method for identifying Armeniacae Semen Amarum from different processed products and various rancidness degrees. The objective odor information of Armeniacae Semen Amarum was obtained by electronic nose. 105 batches of Armeniacae Semen Amarum samples were studied, including three processed products of Armeniacae Semen Amarum, fried Armeniacae Semen Amarum and peeled Armeniacae Semen Amarum, as well as the samples with various rancidness degrees: without rancidness, slight rancidness, and rancidness. The discriminant models of different processed products and rancidness degrees of Armeniacae Semen Amarum were established by Support Vector Machine(SVM), respectively, and the models were verified based on back estimation of blind samples. The results showed that there were differences in the characteristic response radar patterns of the sensor array of different processed products and the samples with different rancidness degrees. The initial identification rate was 95.90% and 92.45%, whilst validation recognition rate was 95.38% and 91.08% in SVM identification models. In conclusion, differentiation in odor of different processed and rancidness degree Armeniacae Semen Amarum was performed by the electronic nose technology, and different processed and rancidness degrees Armeniacae Semen Amarum were successfully discriminated by combining with SVM. This research provides ideas and methods for objective identification of odor of traditional Chinese medicine, conducive to the inheritance and development of traditional experience in odor identification.

Automatic classification of water samples using an optimized SVM model applied to cyclic voltammetry signals / Clasificación automática de muestras de agua usando un modelo SVM optimizado aplicado a señales de voltametría cíclica

Background: concern about the quality of the water for human consumption has become widespread among the population. The taste and some problems associated with drinking water have been the cause of increased demand for bottled water. Due to this, day to day, a large number of companies has manifested their interest in the production of bottled water. Objective: to evaluate a novel automatic classification model that differentiates bottled water from tap water. Methods: the voltammetric technique consisted of three electrode setup. The output current has been considered for data analysis. From the results of grid search, six pairs of values were pre-selected for the parameters of σ and C whose results were similar. High values of accuracy, specificity and sensitivity were achieved in test dataset. The final decision was made after performing an ANOVA test of 100 repetitions of 5-fold cross-validation, 3000 models were evaluated with the parameter combinations described above for the SVM. Results: the oxidation and reduction peaks of the water samples have been observed to be prominent. Absolute values of current (I) increased in the case of public water samples, possibly due to the largest concentration of chloride ions which have higher contributions to the conductivity. 5-fold cross-validation test mean specificity resulted in C parameters values greater than 0 and between 0 and 30; a σ value greater than 10 and between 0 and 15 were found for tap water and bottled water, respectively. The combination (σ = 10, C = 30) presented best results in accuracy 0.988 ± 0.037, specificity 0.973 ± 0.085 and sensitivity 1 ± 0.09. Conclusions: results of this research work have shown that voltammograms for values of current increased for tap water samples, 9.94e-6µA, compared to 7.99e-6µA due to higher chloride ions concentration in the former. The parameters combination (σ = 10, C = 20) was selected as optimal parameters since there were no significant difference between this and the former.

Antecedentes: en la población hay una preocupación generalizada por la calidad del agua de consumo humano. El sabor y algunos problemas asociados con el agua potable han sido la causa del incremento en la demanda del agua embotellada. Debido a esto, un gran número de empresas han manifestado su interés en la producción de agua en botella. Objetivo: evaluar un nuevo modelo de clasificación automática que diferencie el agua embotellada del agua del grifo. Metodología: la técnica de voltametría consistió en la configuración de tres electrodos. Para el análisis de datos se consideró la corriente de salida y de los resultados de la búsqueda de cuadrícula y se seleccionaron seis pares de valores para los parámetros de σ y C, cuyos resultados fueron similares. Se lograron altos valores de precisión, especificidad y sensibilidad en el conjunto de datos de prueba. La decisión final se tomó después de realizar una prueba ANOVA de 100 repeticiones de validación cruzada de 5 veces y se evaluaron 3000 modelos con las combinaciones de parámetros descritas anteriormente para el SVM. Resultados: se observó que los picos de oxidación y reducción de las muestras de agua son prominentes. Los valores absolutos de corriente (I) aumentaron en el caso de muestras de agua pública, posiblemente debido a la mayor concentración de iones de cloruro que tienen una mayor contribución a la conductividad. La especificidad media de la prueba de validación cruzada 5 veces dio como resultado valores de parámetros C mayores que 0 y entre 0 y 30; se encontró un valor σ mayor que 10 y entre 0 y 15 para el agua de red pública y el agua embotellada, respectivamente. La combinación (σ = 10, C = 30) presentó los mejores resultados en precisión 0,988 ± 0,037, especificidad 0,973 ± 0,085 y sensibilidad 1 ± 0,09. Conclusiones: los resultados de este trabajo demostraron que los voltamogramas para valores de corriente, aumentaron para muestras de agua corriente, 9,94e-6 µA, en comparación con 7,99e-6 µA debido a una mayor concentración de iones de cloruro en el primer caso. La combinación de parámetros (σ = 10, C = 20) se seleccionó como parámetros óptimos, ya que no mostró diferencias significativas entre éste y el primer caso.

Estudo e fabricação de dispositivos inteligentes (línguas e narizes eletrônicos) visando à discriminação de contaminação em alimentos / Study and development of smart devices (electronic nose and tongues) aiming at discrimination of contamination in food samples

A proposta da presente tese foi desenvolver dispositivos inteligentes (língua e nariz eletrônicos/ colorimétrico) de baixo custo para discriminar amostras de alimentos contaminados quimicamente e biologicamente. Um dispositivo "optoeletrônico" à base de membranas poliméricas coloridas com indicadores de pH foi utilizado para discriminar compostos voláteis emitidos por micro-organismos (aminas liberadas pelos processos de deterioração dos alimentos e que são produto da descarboxilação de aminoácidos em alimentos predominantemente proteicos). As aminas avaliadas nesse estudo foram: isobutilamina, isopentilamina e trietilamina. O limite de detecção de 5 ppm das aminas foi alcançado utilizando o dispositivo "optoeletrônico" e, esse sistema, também foi testado em amostras reais de carne contaminadas obtendo uma boa discriminação das amostras com e sem as aminas. Aminas biogênicas (cadaverina, tiramina e putrescina) também foram testadas obtendo uma separação pelo gráfico de escores. Em uma segunda etapa o dispositivo também foi avaliado para discriminar quatro espécies de bactérias (Klebsiella pneumoniae, Proteus vulgaris, Proteus mirabilis e Escherichia coli) incubadas a 37°C e 25°C. Em ambos os casos o dispositivo inteligente utilizou um smartphone para registrar as imagens que atuou como detector para extração dos dados de RGB das imagens. A partir dessas informações (valores de RGB), as ferramentas quimiométricas PCA (do inglês Principal Component Analysis, Análise de Componentes Principais) e HCA (do inglês Hierarchical Cluster Analysis, Análise de Agrupamentos Hierárquicos) foram utilizadas para discriminar as amostras e a k-NN (do inglês kth Nearest Neighbor, k- vizinhos mais próximos) para validar o método. Em uma terceira etapa, uma língua eletrônica voltamétrica foi fabricada para discriminar amostras de leite adulteradas com melamina, ureia e formaldeído contendo concentrações finais de 0,95; 4,16 e 10,0 mmol L-1, respectivamente. Essa língua voltamétrica foi composta por três eletrodos metálicos: platina, ouro e cobre e dados voltamétricos foram utilizados como dados de entrada para as ferramentas quimiométricas (PCA e HCA). Foram testados três tipos de leite (integral, desnatado e semidesnatado) de três diferentes marcas e todos eles puderam ser discriminados com sucesso. O trabalho também apresenta a utilização de MIPs (polímeros molecularmente impressos - do inglês, molecularly imprinted polymers) como alternativa para detecção e discriminação de alimentos contaminados fazendo uso da impressão (cavidades) de substâncias químicas contaminantes ou das proteínas específicas de cada micro-organismo presente no processo de deterioração dos alimentos

The present thesis aimed at development of low cost smart devices (electronic tongue and colorimetric nose) to discriminate chemically and biologically contamination in food samples. An "optoelectronic" plastic-based device with colored membranes contained pH indicator was used to discriminate volatile compounds released by microorganisms, due to the deterioration process of protein in food by the organisms. The amines evaluated in this study were: isobutylamine, isopentylamine and triethylamine, achieving a detection limit of 5 ppm. Such system was also tested in real meat samples contaminated with individual amines obtained a good discrimination of samples with and without studied compounds. Biogenic amines (cadaverine, tyramine and putrescine) were also tested and discriminated. In a second step, the device was also evaluated to discriminate four bacteria species (Klebsiella pneumoniae, Proteus vulgaris, Proteus mirabilis and Escherichia coli) incubated at 37 ° C and 25 ° C. In both cases, a smartphone was used as detector to extract RGB values of the samples. From extracted information (RGB values), the chemometric tools PCA (Principal Component Analysis) and HCA (Hierarchical Cluster Analysis) were used to discriminate samples and k-NN (kth Nearest Neighbor) was evaluated to validate the method. In a third stage, a voltammetric electronic tongue was developed to discriminate adulterated milk samples with melamine, urea and formaldehyde. This voltammetric electronic tongue was fabricated using three working electrodes: platinum, gold and copper and the voltammetric data was used as input data for chemometric tools (PCA and HCA). Three types of milk (whole, skimmed and semi-skimmed) from three different brands were tested and all of them could be successfully discriminated

Effects of aroma quality on the biotransformation of natural 2-phenylethanol produced using ascorbic acid

Background Natural 2-phenylethanol (2-PE) is an important flavoring that emits the aroma of roses. During biotransformation, the aroma quality of natural 2-PE is affected by its main by-products, which include butanol, isobutyric acid, butyric acid, and isovaleric acid. Thus, controlling undesirable by-product formation can reduce the effect of odor on 2-PE aroma quality. Results 2-PE was produced through biotransformation using l-phenylalanine as a substrate and glucose as a carbon source. Ascorbic acid was added to the system to improve the redox reaction and suppress the generation of by-products. Principal component analysis of the aroma quality of 2-PE was performed using an electronic nose. Similarity analysis revealed that the effects of four by-products on 2-PE aroma quality may be ranked in the following order: isovaleric acid > butyric acid > isobutyric acid > butanol. The sample that exhibited the best similarity to the standard 2-PE sample (99.19%) was the sample to which ascorbic acid had been added during glucose metabolism. Conclusions 2-PE produced through the addition of ascorbic acid exhibited the closest aroma similarity to the standard 2-PE sample.

Discrimination of Coptidis Rhizoma and its processed products by odor objectify / 中国中药杂志

Different processed products of Coptidis Rhizoma have its unique odor, which is an important assessment index for pro- cessed products identification of Coptidis Rhizoma. Objectify odor as an entry point in this study, an electronic nose technology was used, and a suitable method for Coptidis Rhizoma measurement was built firstly. Then different processed products of Coptidis Rhizoma were detected by the method built. Finally, different processed products were identified by combining with chemometrics based on the objective odor information obtained. Electronic nose detection indicated that a significant difference in odor between different processed products was performed. Coptidis Rhizoma processed or not can be distinguished based on statistical quality control (SQC) and soft independent modeling of class analogy (SIMCA). Principle component analysis (PCA) model showed that Coptidis Rhizoma and its various processed products discriminated obviously. In addition, in order to identify the processed products of Coptidis Rhizoma, a correct recognition rate of 100% was acquired by discriminant factor analysis (DFA) , and the initial identification rate and cross-validation recognition rate of linear discriminant analysis (LDA) is 100%, 94.4% respectively. In conclusion, differentiationin odor of different processed Coptidis Rhizoma was performed by the electronic nose technology used, and different products Coptidis Rhizoma were dis- criminated by combining with chemometrics. This research can be a reference for objective identification in odor of traditional Chinese medicine, and is good for the inheritance and development of traditional experience in odor identification.

Análisis del aroma de las gotas de papaya mediante los métodos de nariz electrónica y aceptabilidad sensorial / Analysis the flavor of papaya drops by the methods of electronic nose and sensory acceptability

The objective of this study was to evaluate the behavior of the flavor of papaya drops during refrigerated storage and to correlate the data generated from the electronic nose with that of the sensory analysis. The drops were obtained by basic spheronization process of the papaya pulp. After drops were obtained they were subjected to sensory evaluation and the electronic nose for 16 days of storage at +5° C. Sensory data showed a slight decrease of acceptance (p < 0.05). The results generated by the electronic nose showed there were subtle changes in the flavor during storage, with a small increase in the concentration of organic solvents and the concentration of ammonia and hydrogen sulfide. There was a good correlation between sensory analysis data generated by the sensors of the electronic nose.

El objetivo del estudio fue evaluar el comportamiento del aroma de las gotas de papaya durante el almacenamiento refrigerado y hacer una correlación de los datos generados de la nariz electrónica con los datos del análisis sensorial. Las gotas fueron obtenidas por un proceso de esferificación básica de la pulpa de papaya. Después de la obtención, estas fueron sometidas a evaluaciones sensoriales y con el equipo de la nariz electrónica durante 16 días de almacenamiento a + 5° C. Los datos sensoriales obtenidos con el almacenamiento mostraron una ligera disminución de la aceptación (p < 0,05). Los resultados generados por la nariz electrónica mostraron que hubo cambios sutiles en el aroma durante su almacenamiento, con un pequeño aumento en la concentración de disolventes orgánicos y en la concentración de amoníaco y sulfuro de hidrógeno. Se observó una buena correlación entre los datos del análisis sensorial y los generados por los sensores de la nariz electrónica.

Exhaled Breath Analysis System based on Electronic Nose Techniques Applicable to Lung Diseases / 한양의대학술지

Smell used to be a common diagnostic tool in medicine, and physicians were trained to use their sense of smell during their medical training. Latterly, odor disgnostics have been relegated to secondary status as a diagnostic method. Array-based gas sensors ("Electronic Nose") now offer the potential of a robust analytical approach to exhaled breath analysis for medical use. Many diseases are accompanied by characteristic odor, and their recognition can provide diagonostic clues, guide the laboratory evaluation, and affect the choice of immediate therapy. We are developing an intelligent sensor system for non-invasive health care monitoring combined laboratory based sensor module, pattern recognition subsystem and non-invasive sampling of volatile emitted from a patient into a highly intelligent sensor system that allows the rapid processing of these samples. It is capable to assist early and rapid disgnosis of changes in state of patient, and aid decision making by medical personnel in the treatment of such patients. In this paper, we introduce exhaled breath analysis for potential primary lung disease screening using electronic nose system incorporating an automated solid-phase microextraction (SPME) desorption to enable the system to be used. Aiming to increase the sensitivity, SPME preconcentration is used for sampling of headspace air and the response of sensor module to variable concentration of volatile emitted from SPME fiber is evaluated. The initial result shows the distinguished difference between the lung cancer patients and healthy normal individuals according to the analysis of the respective expiratory gases.

Síntese de poli ( p-fenilenovinileno )s e desenvolvimento e otimização de um nariz eletrônico / Synthesis of poly ( p-phenylenevinylene )s and the development and optimization of an electronic nose

O presente trabalho envolve a síntese e caracterização de um polímero da família dos poli(p-fenilenovinileno)s (PPV), aplicável em camadas ativas de dispositivos como narizes eletrônicos, muito utilizados em várias áreas, como medicina, meio ambiente e indústria alimentícia. O trabalho visou também ao desenvolvimento de um nariz eletrônico, abrangendo o processo de preparação, o que incluiu a confecção dos eletrodos dos sensores de gases, o estudo referente ao equipamento de aquisição de dados e à comunicação com o microcomputador. Visou-se à otimização do equipamento que já vem sendo utilizado em medidas para várias detecções, estudando-se fatores como frequência da corrente alternada empregada, forma de onda (senoidal, quadrada e triangular), temperatura da amostra e distância entre os dígitos nos eletrodos. Verificou-se a possibilidade da utilização de nariz eletrônico na área de alimentos, estudando-se a identificação de méis de abelha de floradas diferentes e a detecção de fungos em laranjas pós-colheita

The present thesis involves the synthesis and characterization of a polymer of the poly(p-phenylenevinylene) (PPV) family, applicable as active layer of devices such as gas sensors and electronic noses, which are instruments widely used in several areas, including medicine, environmental sciences and food industry. This work also aimed the full development of an electronic nose, from the making of the electrodes and sensors to the study of the data acquisition and its communication with a personal computer. In order to optimize the equipment, the influence of several factors such as frequency of the applied alternating current, its waveform (sine, square and triangle), temperature of the sample, and spacing between the digits of the electrodes were investigated. Finally, the equipment was used for the identification of honeys from different blossoms and for the detection of fungi in post-harvest oranges

Research on correlation between odor and chemical compounds of Lonicera japonica / 中国中药杂志

This study aims to investigate the relationship between odor and contents of the chemical compounds in Lonicera japonica, including chlorogenic acid, galuteolin and polyphenols. High performance liquid chromatography (HPLC) was applied to determine the contents of chlorogenic acid and galuteolin in L. japonica. The ponptent of polyphenols was determined by UV-Vis Spectrophotometry. Electronic nose was used to extract and measure the odor of L. japonica. Then SPSS 17.0 software was employed for data processing. There is a significant positive correlation between the comprehensive index value of aroma and the contents of chlorogenic acid and polyphenols. The regression equations have been established. However, the relationship between the comprehensive index value and the content of galuteolin is not obvious. This is proof that the odor of L. japonica has close connection with the chemical compounds. Therefore, this research offered a new method for initially determine or predict the content of the chemical composition in L. japonica,

Optimization method of MOS sensor array for identification of traditional Chinese medicine based on electronic nose / 中国中药杂志

Optimization of sensor array is a significant topic in the application of electronic nose (EN). Stepwise discriminant analysis and cluster analysis combining with screening of typical index were employed to optimize the original array in the classification of 100 samples from 10 kinds of traditional Chinese medicine based on alpha-FOX3000 EN. And the identification ability was evaluated by three algorithm including principle component analysis, Fisher discriminant analysis and random forest. The results showed that the identification ability of EN was improved since not only the effective information was maintained but also the redundant one was eliminated by the optimized array. The optimized method was eventually established, it was accurate and efficient. And the optimized array was built up, that is, S1, S2, S5, S6, S8, S12.

Rapid Clinical Bacteriology and Its Future Impact

Clinical microbiology has always been a slowly evolving and conservative science. The sub-field of bacteriology has been and still is dominated for over a century by culture-based technologies. The integration of serological and molecular methodologies during the seventies and eighties of the previous century took place relatively slowly and in a cumbersome fashion. When nucleic acid amplification technologies became available in the early nineties, the predicted "revolution" was again slow but in the end a real paradigm shift did take place. Several of the culture-based technologies were successfully replaced by tests aimed at nucleic acid detection. More recently a second revolution occurred. Mass spectrometry was introduced and broadly accepted as a new diagnostic gold standard for microbial species identification. Apparently, the diagnostic landscape is changing, albeit slowly, and the combination of newly identified infectious etiologies and the availability of innovative technologies has now opened new avenues for modernizing clinical microbiology. However, the improvement of microbial antibiotic susceptibility testing is still lagging behind. In this review we aim to sketch the most recent developments in laboratory-based clinical bacteriology and to provide an overview of emerging novel diagnostic approaches.