• Journal of Marine Bioscience and Biotechnology
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• v.14 no.2
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• pp.69-75
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• 2022

The micro-Kjeldahl method, a common technique for analyzing crude proteins, is time-consuming and dangerous due to the employment of reagents such as sulfuric acid and sodium hydroxide. However, a Fourier transform near-infrared (FT-NIR) spectrophotometer analysis can be completed in under a minute after simple pre-processing if data has been gathered using sufficient reference material in advance. Furthermore, the use of safe reagents in this technique ensures the safety of the experimenter and the environment. In addition, a portable FT-NIR spectrophotometer enables real-time measurement at processing or distribution sites and has recently gained popularity. The standard errors of calibration and regression (r²) for the calibration result for estimating the crude protein content of dried laver were 0.9775 and 1.2526, respectively. The standard error of prediction was 1.1814, and the r² was 0.9303 in the validation results, which was a good level. In the present study, a method for predicting the crude protein content of dried laver using an FT-NIR spectrophotometer in the range of 29%-40% crude protein content has been reported.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.48-48
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• 2021

This study was carried out to investigating quality and nutritional traits of melon genetic resources. It could provide important baseline data in breeding for increased β-Carotene, cucumisin content thereby increasing the marketability of melon. To this end, we have examined some fruit morphological traits and β-Carotene, cucumisin content of 163 genetic resources. The morphological characters were recorded on the field and inside laboratory and nutritional contents for β-carotene, cucumisin was measured using spectrophotomertic and HPLC methods. Melon fruits have shown a diverse morphological characters. Green and white is dominant for fruit skin color and round and oval-shape is dominant for form in the entire collections. The β-carotene content varied between 0.5 and 233.6mg/kg, 0.7 and 226.5mg/kg, 0.4 and 189.0 mg/kg using UV-Vis and microplated reader instruments, HPLC respectively. The high β-carotene contents were characterized five melon fruit originated from South Africa, Uzbekistan, Albania, France. The cucumisin content varied between 0.3 and 33.5 unit/mg, 0.29 and 32.1unit/mg using UV-Vis and microplated reader instruments, respectively.

• Journal of Food Hygiene and Safety
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• v.4 no.3
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• pp.177-184
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• 1989

Contents of inorganic compounds in various cereals (Rice: 62, Barley: 39, Soybean: 58, Unhulled barley: 59) collected from Youngnam Districts in 1989 were determined by the atomic absorption spectophotometer. The results abtained as follows: The ranges of zinc level in rice, barley, soybean and unhulled barley were 46.91-76.28 ppm, 42.24-77.06 ppm, 73.39-103.69 ppm and 48.08-272.49 ppm, and those of manganes in each samples were 4.96-14.75 ppm, 20.62-16.28 ppm, 23.31-42.488 ppm and 23.52-30.15 ppm respectively. The ranges of iron level in rice, barley, soybean and unhulled barley were 65.38-141.33 ppm, 52.22-133.25 ppm, 106.32-240.20 ppm and 66.44-108.64 ppm, and those of calcium in each samples were 10.25-33.67 ppm, 68.94-136.62 ppm, 492.20-967.84 ppm and 75.30-165.85 ppm respectively. Meanwhile, contents of sodium in rice, barley, soybean and unhulled barley were 291.60-453.60 ppm, 462.25-773.60 ppm, 463.83-792.67 ppm and 777.90-950.90 ppm and those of potassium in above samples were 716.00-1180.60 ppm, 1363.60-1686.00 ppm, 2233.84-2792.67 ppm and 2042.10-2141.46 ppm respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.202-211
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• 2004

Xylitol is a 5-carbons carbohydrate, which can be replaced with sucrose for preventing dental caries. To study the effect of xylitol on the fermentation of lactose in bacteria, the important oral bacteria such as Streptococcus(S.) mutans, S. oralis and S. salivarius were studied. The optical density using spectophotometer and the cell concentration were assessed to evaluate the combined effect of lactose and xylitol against the bacteria. Thin layer chromatography and lactose-PTS activity test were performed to evaluate the effect of xylitol on the fermentation of lactose in S. mutans and by ${\beta}-galactosidase$ with the following results. 1. The optical density of Streptococcus mutans culture was not increased for 8 hours-incubation in the media added with lactose and xylitol, but was increased at 24 hours-incubation. The number of viable cells at 8 hours-incubation was smaller in the media containing lactose and xylitol in comparison with lactose only. 2. The optical densities of Streptococcus oralis culture and Streptococcus salivarius culture were not increased for 8 hours-incubation in the media added with lactose and xylitol but were increased at 24 hours-incubation. 3. When Streptococcus mutars was incubated for 8 hours in the media added with lactose and xylitol, the amount of remained lactose was larger compared with the media added with lactose only But all lactose was fermented in both media after 24 hours-incubation. 4. When Streptococcus mutans was incubated in the media added with lactose and xylitol, the activity of lactose-PTS was higher compared with the media added with lactose only. 5. When ${\beta}-galactosidase$ was incubated in the media added with lactose and xylitol, the amount of remained lactose was larger compared with the media added with lactose only. These results indicated that xylitol inhibited the fermentation of lactose by Streptococcus.