• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.301-308
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• 2024

Ceramic materials are being explored as alternatives to toxic lead sheets for radiation shielding due to their favorable properties like durability, thermal stability, and aesthetic appeal. However, crafting effective ceramics for radiation shielding entails complex processes, raising production costs. To investigate local viability, this study evaluated Malaysian ceramic tiles for shielding in diagnostic X-ray rooms. Different ceramics in terms of density and thickness were selected from local manufacturers. Energy Dispersive X-ray Fluorescence (EDXRF) and X-ray Fluorescence (XRF) characterized ceramic compositions, while Monte Carlo Particle and Heavy Ion Transport code System (MC PHITS) simulations determined Linear Attenuation Coefficient (LAC), Half-value Layer (HVL), Mass Attenuation Coefficient (MAC), and Mean Free Path (MFP) within the 40-150 kV energy range. Comparative analysis between MC PHITS simulations and real setups was conducted. The C3-S9 ceramic sample, known for homogeneous full-color structure, showcased superior shielding attributes, attributed to its high density and iron content. Notably, energy levels considerably impacted radiation penetration. Overall, C3-S9 demonstrated strong shielding performance, underlining Malaysia's potential ceramic tile resources for X-ray room radiation shielding.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.70-79
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• 1996

Yogurts were prepared with skim milk powder added with jujube extract of 0%, 1%, 2%, 3%, 4%, 5%, respectively and fermented by mixed culture(Str. thermophilus, and Lac. bulgaricus). The fermented yogurts were evaluated for acid production(pH, titratable acidity), number of viable cell, change of sugars, sensory properties. 1. Addition of jujube extract increased acid production and decreased pH. Acid production was increased in proportion to concentration of jujube extracts added to milk and pH was decreased. 2. In yogurt fermentation, the lactic acid bacteria of yogurt added with jujube extract, increased in proportion to jujube extract concentration added to milk. 3. The viscosity was increased in proportion to concentration of jujube extract during 6 hrs. of fermentation. The viscosity of yogurt added with 4% and 5% jujube extract remarkably decreased for the first 12 hrs. Yogurt added with 5% jujube extract is lowest in its viscosity among the treatments. 4. The concentrations of glucose and fructose were higher in proportion of jujube extract add at 0 hrs. the concentration of lactose was decreased simultaneously, and those of galactose was increased in all the samples at 12 hrs. 5. The taste and odor of yogurt added with the jujube extract of 4% and 5%, respectively, were better than other samples. The color of control was better than other samples. The texture of control yogurt was better than orther samples, but was not clearly difference with the yogurts added with jujube extract of 4% and 5%. In the overall acceptability, the sensory scores of yogurt added with jujube extract of 3% and 4% were higher than other samples.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.66-75
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• 2003

This experiment was carried out to examine the fermentation properties of yogurt added fresh mulberry, freeze dried-mulberry and heated air dried-mulberry at concentrations of 0%, 0.3%, 0.6% and 0.9%. Lactic acid bacteria was used mixed starter culture(Str.salivarius ssp. thermophilus and Lac. delbrueckii ssp. bulgaricus). We obtained excellent results from the yogurt added fresh mulberry. In yogurt added 0.9% fresh-mulberry, lactic acid contents and titratable acidity were higher than those of 0%, 0.3%, 0.6% fresh-mulberry added. Also, sensory scores of color, taste and overall acceptability of the yogurt with 0.9% fresh mulberry was higher than those of any other groups.

• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.197-203
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• 2009

An indole oxygenase originated from Rhodococcus sp. RHA1 was cloned into the expression vector, pTrc99A, in Escherichia coli, and designated pTCAN1. The pTCAN2 was constructed from pTCAN1 by the deletion of $lacI^q$ for the constitutive expression of indole oxygenase without adding IPTG in the medium. The complete open reading frame of indole oxygenase was 1,224 bp long, which encodes a protein of 407amino acids. Crude extracts of E. coli $DH5{\alpha}$/pTCAN1 and pTCAN2, respectively, were prepared and subjected to SDS-PAGE analysis. A band corresponding to molecular mass of about 43 kDa was appeared and this result correlated with the predicted molecular mass of cloned indole oxygenase. The E. coli harboring pTCAN1 and pTCAN2, respectively, showed blue color colony in LB plate. The pigment showing blue color was prepared from E. coli $DH5{\alpha}$/pTCAN2, and identified as indigo by experiments using spectrophotometer, HPLC, and TLC. The indigo-forming activity of indole oxygenases from the whole cell of E. coli $DH5{\alpha}/pTCAN1$ cultured at LB medium added 1mM of IPTG and that of E. coli/pTCAN2 showed about 1.75nmol/min/mg DCW (dry cell weight) and 3.85 nmol/min/mg DCW, respectively. Also, the E. coli $DH5{\alpha}$/pTCAN2 produced about $236{\mu}M$ of indigo after 48 hours incubation in TB medium supplemented with 2.5 mM of tryptophan.

• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.1-7
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• 2004

Yoghurt base was prepared from skim milk added with 0.25∼2.0%(w/v) of chlorella extract powder and fermented with lactic acid bacteria(Streptococcus thermophilus : Lactobacillus casei = 1:1) at 37$^{\circ}C$ for 24 hours. Quality characteristics of the yoghurts were evaluated in terms of acid production, number of viable cell, color, texture property, and sensory property during lactic acid fermentation. The addition of 0.25% chlorella extract powder stimulated the growth of lactic acid bacteria which showed the highest number of viable cell counts(l.46${\times}$10$\^$8/ CFU/mL) after 12 hours incubation, and also enhanced the acid production which was pH 4.33 after 12 hours incubation. The L values(brightness) of the yoghurts containing chlorella extract powder were lower than control group, whereas the b values(yellowness) were higher. The hardness and gumminess of the yoghurt added with 0.25% chlorella extract powder were higher than others. Sensory scores of the yoghurt added with 0.25% chlorella extract powder were significantly higher than other groups in color, chlorella odor, sweet taste, chlorella taste, mouth feel, aftertaste and overall acceptability.

• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.657-666
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• 2008

This study investigated the effects of dietary probiotics which contained antioxidant astaxanthin on growth performances and meat quality in two pigs farms. A total of 2,400 pigs were gilt and barrow with same number assigned to one of two treatments. The two treatments were control(commercial feed), treatment(probiotics 0.1% feed). Each treatment had 3 replicates. Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. Survival ratio was shown 99.85% in treatment group. Average daily gain was higher in treatment group(0.91kg) than that of control(0.84kg). Back fat thickness was lower in treatment group than that of control, even though the treatment group tended to be higher carcass weight. The treatment group trended higher carcass weight, back fat thickness was lower in treatment group than control. The ratio of carcass grade A was shown higher in treatment than that of control, respectively. Treatment group showed higher value of fat content and water holding capacity. Treatment showed lower value than control in shear force and cooking loss. Hunter value(a and b) of treatment group in meat color was higher than control. Treatment group was lower cholesterol content than control. Control group was shown higher unsaturated fatty acid(stearic acid(C18:0)) value than treatment. Treatment group was shown lower saturated fatty acid(oleic acid(C18:1)) value than that of control. These results suggested that the supplementation of probiotics contained Phaffia rhodozyma could be used effectively for increase productivity of livestock industry.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.655-666
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• 2005

This study was performed to measure physicochemical and textural characteristics, and shelf-life effect of low-fat functional sausages(LFFSs) manufactured with sodium lactate(SL, 3.3%), lac pigment and various molecular weights(MWs) of chitosan (Low=1.5 kDa, Med=30-50 kDa and High=200 kDa) during storage at 15$^{\circ}C$ for 18 days. LFFSs had 73.7-76.0% moisture, lower than 3% fat and 14-15% protein, respectively. pH values were 6.05-6.44 and the control(150 ppm, $NaNO_2$) was the lowest among LFFSs (p<0.05). Increasing storage time decreased pH values, but no differences in pH values were observed up to 6 days of storage (p>0.05). LFFSs containing SL and low MW of chitosan improved water holding capacity (WHC) and different from those with SL and medium-MW chitosan. WHC was decreased with increased storage time and differences of WHC were observed from 18 days of storage. The addition of chitosan reduced both lightness and redness values, as compared to 150 ppm sodium nitrite(SN), and increased storage time decreased yellowness(p<0.05), especially at 12 days of storage. LFFSs with SL and medium-MW chitosan increased most textural properties compared to the control(p<0.05). The addition of SN of 150 ppm in LFFSs retarded microbial growth for E. coli 0157:H7, while those with SL tended to have an antimicrobial effect for Listeria monocytogenes(LM). The growth rate of LM was delayed by addition of various MW of chitosans in LFFSs, especially high MW chitosan, as compared to LFFSs containing SL alone. These results indicated that the functional, textural and antimicrobial effects of LFFSs were improved by addition SL and various MW of chitosan combinations. In addition, 0.05% lac pigment improved the cure color of LFFSs similar to those of 150 ppm SN.