Avaliação do ponto de congelamento do leite cru por espectroscopia de infravermelho com transformada de Fourier como método de triagem / [Fourier Transform Infrared spectroscopy (FTIR) as a screening method for freezing point in raw milk]

O objetivo deste estudo foi investigar a interferência do teor de gordura do leite no ponto de congelamento (PC) obtido pelo infravermelho com transformada de Fourier (FTIR). Uma fração de leite cru foi desnatada, obtendo-se creme e leite desnatado. O leite integral e o desnatado foram adicionados com água (0%, 2%, 5%, 10%, 15% e 20%). O leite desnatado remanescente foi adicionado com creme (5%, 10%, 15%, 20%) e água (0%, 2%, 5%, 10%, 15% e 20%). As amostras foram analisadas para PC (crioscópio eletrônico e FTIR) e composição (FTIR). O PC medido por FTIR foi altamente correlacionado com o método do crioscópio eletrônico (acima de 98,5%) e, como esperado, a adição de água foi significativa (P≤0,001) ao aumentar o PC do leite em ambos os métodos. No entanto, o alto teor de gordura no leite cru resultou na redução do PC ao se utilizar o FTIR, enquanto o baixo teor de gordura resultou em aumento do PC (P≤0,001). Uma vez que a adição de água causou o efeito inverso do alto teor de gordura no PC medido por FTIR, é importante considerar o teor de gordura do leite para evitar interpretações erradas do PC quando se utiliza o método FTIR.(AU)

The objective of this study was to investigate the interference of milk fat content upon the Freezing Point (FP) obtained by Fourier-transform infrared (FTIR). A fraction of raw milk was skimmed, obtaining cream and skim milk. Whole and skim milk were added with water (0, 2, 5, 10, 15, and 20%). The remaining skim milk was added with cream (5, 10, 15, 20%) and water (0, 2, 5, 10, 15, and 20%). Samples were analyzed for FP (thermistor cryoscope and FTIR) and composition (FTIR). FP measured by FTIR was highly correlated with the thermistor cryoscope method (above 98.5%) and, as expected, water addition was significant (P≤0.001) upon increasing milk FP in both methods. However, high fat content in raw milk resulted in decreasing FP when using FTIR, while low fat content resulted in increased FP (P≤0.001). Since water addition caused the inverse effect of high fat on FP measured by FTIR, it is important to regard the fat content of milk to avoid misinterpretation of FP when using the FTIR method.(AU)

A Study of Chemical Composition of Gall Stones in a Tertiary Care Hospital.

Gallstones are a major health problem & have been recognized since antiquity. Gallstones are generally classified into pure cholesterol, pigment and mixed type. Knowing the chemical composition of gallstones is essential for determining etiopathogenesis of gallstone disease. Fourier Transform Infrared Spectroscopy (FTIR) method is the most widely used technique in chemical analysis of gall stones. Reports on chemical analysis of gallstones are available from different endemic regions of India. However, no reports are available about the composition and etiopathogenesis of gallstones in Himachal Pradesh. METHODSGallstones from 400 patients of cholelithiasis were collected after cholecystectomy at Indira Gandhi Medical College Hospital (I.G.M.C.), Shimla, between June 2016 to June 2018, and were subjected to chemical analysis by FTIR method. The data was further correlated with regard to age, gender, socio-economic status, various life style factors like diet, obesity, physical activity, with stone number and colour. RESULTSChemical analysis of gall stones revealed that pure cholesterol, mixed and pigment variety were 94 %, 2 % and 4 % respectively. Majority of the patients were below the age of 50 years (66 %). Male to female ratio was 2.7:1. Both sexes had predominantly pure cholesterol stones. Most of the patients belonged to the lower middle class (56.5 %) & all socio-economic classes showed predominantly pure cholesterol stones. Similarly, there was no predilection of any type of stone to a particular physical work category. 53.5 % patients were non-vegetarians and 46.5 % were vegetarians. There was no correlation between diet and BMI with type of stones. In our study, 66 % of patients had multiple stones. Multiple stones were seen in all varieties of stones. Pure cholesterol stones showed a variety of colours contrary to traditional classification. CONCLUSIONSIn Himalayan population, the predominant type of gall stones were pure cholesterol stones. Mixed stones and pigment containing stones were found in much smaller frequencies. This result is in contrast to that of rest of the Indian subcontinent from where larger percentage of pigment and mixed stones has been reported. And pure cholesterol stones showed maximum variation in colours contrary to our expectation.

FTIR identification between Amomum villosum hybrid offspring and female parent / 中草药

Objective: To study the identification between the Amomum villosum hybrid offspring and the female parent by useing the Fourier transform infrared (FTIR) spectroscopy. Methods: Using the FTIR to determine the infrared spectra of A.villosum hybrid offspring and female parent. Switching and processing the atlas with derivative spectrometry and Fourier self-deconvolution, to contrast for the characteristic differences in absorbance of them. Results: There were no significant differences between the A. villosum hybrid offspring and female parent by using FTIR. But 1 051.014 cm-1 was found to be the most obvious in the fourth-derivative spectrum, 771.563 4 and 1 612.432 5 cm -1 to be the most obvious in the Fourier self-deconvolution spectra. Conclusion: There are obvious differences between the A. villosum hybrid offspring and female parent in the derivative spectrometry and Fourier self-deconvolution spectroscopy atlas. Therefore, this method can be used to identify the A.villosum hybrid offspring and female parent simply, rapidly, and accurately.

Study on FTIR Spectroscopy of Akebia Trifoliate / 国际中医中药杂志

Objective To study the identification method of Akebia trifoliata(Thunb.) Koidz. by Fourier Transform Infrared (FTIR) Spectroscopy. Methods FTIR Spectroscopy was measured of Akebia trifoliate collected from different production areas. Results At the range of 737-1032cm-1, the Spectroscopy of Akebia trifolia of different production areas showed variances in peak value of infrared absorption, peak position, peak shape and peak strength, which can be regarded as identification evidence for Akebia trifoliate. Conclusion This mehthod is rapid, reliable, simple and effective. FTIR can be used as the identification index for Akebia trifoliate.