• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.1031-1031
• /
• 2001

The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.

• Current Research on Agriculture and Life Sciences
• /
• v.29
• /
• pp.83-89
• /
• 2011

Various functional and useful components in Portulaca oleracea were extracted with ethanol and the optimum solvent conditions were set by monitoring of response surface methodology(RSM). A central composite design for optimization was applied to investigate the effects of the three independent variables of extraction temperature, ethanol concentration, and extraction time, on dependent variables including total phenolics, electron-donating ability, brown clolor and total flavonoids of Portulaca oleracea. The content of total phenol was essentially unaffected by extraction time or extraction temperature, but it was highly influenced by ethanol concentration. The maximum total phenol content was 31.70mg/mL obtained at 45.84% of ethanol concentration, $79.66^{\circ}C$, and after 2.67hr of extraction. Electron-donating ability (EDA) was affected by ethanol concentration and the maximum EDA was 74.67mg/mL at 52.95% ethanol concentration, $52.33^{\circ}C$ and 4.84hr of extration time. The browning color was rarely affected by extraction time but, it was highly influenced by ethanol concentration and extraction temperature. The maximum extent of browning color was obtained at 97.75% of ethanol concentraion, $65.88^{\circ}C$ and 2.93hr of extraction time. The content of total flavonoid was significantly influenced by extraction time, and the maximum total flavonoid level was 58.28mg/mL obtained at 96.62% ethanol concentration, $61.87^{\circ}C$ after 3.70hr of extraction. As a result, The optimal conditions for effective extraction were predicted as follows, 70.3% of ethanol concentration, $62.1^{\circ}C$ of extraction temperature and 3.3hr of extraction time.

• Food Science and Preservation
• /
• v.15 no.1
• /
• pp.58-65
• /
• 2008

The Acorn (Quercus acutissima CARRUTHERS), which contains a large quantity of tannin, should be developed as a processed food as the acorn is rich in natural antioxidants and other valuable components. Accordingly, acorn extraction conditions for polyphenol and gallic acid (both antioxidants) were investigated by response surface methodology. The content of polyphenols were determined under 16 different extraction conditions based upon a central composite design. The parameters varied over $30-70^{\circ}C$ of extraction temperature, 1-5 h of extraction time, and 5-25 mL/g of solvent ratio, Gallic acid extraction was optimal at $60-100^{\circ}C$ extraction temperature, 1-5 h of extraction time, and 5-25 mL/g of solvent ratio, Epicatechin content was highest at $56.77^{\circ}C$, 4.16 hand 22.38 mL/g. Catechin content was highest at $52.37^{\circ}C$, 2h and 23.59 mL/g. The maximum catechin content was $91.30{\mu}g/mL$. Epigallocatechin content was influenced by extraction temperature and time. The maximum epigallocatechin content was $1,066.56{\mu}g/mL$ at $61.42^{\circ}C$, 4.17h, and 9.25 mL/g. The maximum value of epicatechingallate content was $125.39{\mu}g/mL$ at $47.72^{\circ}C$, 3.04h, and 24.93mL/g. Epigallocatechingallate content was influenced principally by solvent ratio and the maximum content was $61.38{\mu}g/mL$ at $48.11^{\circ}C$, 2.96h, and 24.95mL/g. The total polyphenol content was maximal at $1,332.75{\mu}g/mL$, after extraction at $61.50^{\circ}C$, 4.24h, at 9.71mL/g. The higher the extraction temperature and the longer the extraction time, the greater the polyphenol content. Gallic acid content was highest, the maximal level was $30.51{\mu}g/mL$ after $65.84^{\circ}C$, 1.65h at 17.17 mL/g, and this was influenced principally by extraction time and solvent ratio.

• Restorative Dentistry and Endodontics
• /
• v.18 no.1
• /
• pp.73-83
• /
• 1993

The purpose of this study was to evaluate the effect of various acid treatments on dentin bonding. Freshly extracted human teeth were uprightly embedded in self curing acrylic resin, and their occlusal surfaces were grinded to expose flat dentin surfaces. The specimens were divided into 4 groups. Specimens of one group were not treated so as to be a control and those of the other three groups were threated with 10% polyacrylic acid, 10% phosphoric acid, and 10-3 solution(10% citric acid/3% ferric chloride) respectively. Primer, bonding resin and composite resin were applied over the treated dentin surfaces sequentially. All specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured and the treated dentin surfaces and fracured dentin surfaces were examined under a scanning electron microscope. The results were as follows: Bond strengths of acid-treated groups were higher than those of the untreated group. In the acid-treated groups, bond strength was found to be the highest in the 10-3 solution group followed by the 10% phosphoric acid group and the 10% polyacrylic acid group(P<0.01). On SEM examination of dentin surfaces, the untreated dentin surface showed a remaining smear layer and closed dentinal tubules. Dentin surfaces treated with 10 % polyacrylic acid showed a clean dentin surface without the smear layer, but showed remaining smear plugs in dentinal tubules. A dentin surface treated with 10% phosphoric acid or 10-3 solution showed open dentinal tubules without the smear layer or smear plugs. On SEM observation of the fractured dentin-resin interface, the untreated group showed that failure occurred in the smear layer. The group treated with 10% polyacrylic acid showed no resin tag remained in the dentinal tubules, but resin tags in the dentinal tubules were observed in the group treated with the 10% phosphoric acid or the 10-3 solution. On the failure mode examination, the higher the bond strength of the group, the higher the frequency of cohesive failure. The coefficient between bond strength and cohesive failure rate was 0.71.

• Food Engineering Progress
• /
• v.15 no.4
• /
• pp.388-397
• /
• 2011

The purpose of this study was to determine the optimum ethanol extraction conditions for maximum extraction of functional components such as ferulic acid, oryzanol, and toopherol from black rice bran using Response Surface Methodology (RSM). A central composite design was applied to investigate the effects of the independent variables of solvent ratio ($X_{1}$), extraction temperature ($X_{2}$) and extraction time ($X_{3}$) on the dependent variables such as total phenol components ($Y_{1}$), total flavonoids compounds ($Y_{2}$), electron donating ability ($Y_{3}$), $\gamma$-oryzanol ($Y_{4}$), ferulic acid ($Y_{5}$) and $\alpha$-toopherol components ($Y_{6}$). ANOVA results showed that coefficients of determination (R-square) of estimated models for dependent variables ranged from 0.8939 to 0.9470. It was found that solvent ratio and extraction temperature were the main effective factors in this extraction proess. Particularly, the extraction efficiency of ferulic acid, $\gamma$-oryzanol and $\alpha$-toopherol components were significantly affected by extraction temperature. As a result, optimum extraction conditions were 20.35 mL/g of solvent ratio, 79.4$^{\circ}C$ of extraction temperature and 2.88 hr of extraction time. Predicted values at the optimized conditions were acceptable when compared with experimental values.