• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.209-214
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• 1978

Naringinase produced from Aspergillus nidulans was immobilized in acrylamide gel by the entrapping method and its characteristics were studied. Optimum acrylamide concentration was 10%, but N.N'-methylene bisacrylamide concentration had no influence on the final enzyme gel activity. The suitable amount of enzyme dissolved in the polymerization reaction mixture was 126 units/ml. Optimum pH of immobilized enzyme was 5.0 which was the same as that of free enzyme. However, immobilized enzyme showed a higher optumum reaction temperature, markedly increased pH and temperature stability. In a packed-column reactor, the observed reaction rate was increased proportionally to flow rate up to 5ml/min., but independent above 6ml/min.. Activation energy of the immobilized enzyme was 13.01 Kcal/mole, and the energy required for the thermal inactivation was 39.4 Kcal/mole. The apparent Km for 100 mesh gel was $7.23{\times}10^{-3}$ mole.

• Polymer(Korea)
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• v.25 no.4
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• pp.460-467
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• 2001

Inverse suspension polymerization of acrylamide (AM) in cyclohexane was carried out to study the effects of concentrations of sorbitan ester (Span) stabilizers and 2,2'-azobis (2-methyl propionamidine) dihydrochloride (AIBA) initiator, amount of monomer, shaking speed, and polymerization temperature on the particle size of the resulting poly (acrylamide) (PAM) beads and their molecular weights. It was found that the particle diameter. in general, decreased with increasing concentration of stabilizer, shaking speed, and water content in the aqueous phase, and with decreasing concentration of initiator and polymerization temperature. The average molecular weight of the resulting PAM beads was also found to increase with increasing concentrations of monomer and stabilizer, and also with decreasing concentration of initiator, polymerization temperature, and water content in the aqueous phase. In this study, PAM beads ranging 2 ~ 50 ${\mu}$m in diameter, with 8000000 ~ 12000000 in the weight average molecular weight were successfully prepared in almost 100% conversion.

• Polymer(Korea)
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• v.31 no.5
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• pp.374-378
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• 2007

Water-soluble terpolymer of acrylamide, diacetone acrylamide, and acrylic acid was prepared by redox initiators in aqueous medium. One component photoresist was synthesized by reaction of terpolymer with 4-azidoaniline. By blending the aqueous acrylamide/diacetone acrylamide copolymer solution with bisazide, 4,4'-diazidostilbene -2,2'-disulfuric acid sodium salt, two component photoresist was prepared. The photosensitivity per azido group unit mole of one component photoresist was 4 times higher than that of two component photoresist. The dot-type pattern was successfully achieved with one component photoresist at low exposure energy, which is prospective to be used as black matrix negative photoresist.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.299-308
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• 1976

Cerium (Ⅳ) ion-initiated graft copolymerizations of acrylamide and of acrylonitirile to silk fibroins were investigated. When acrylamide was used, the change in ceric ammonium nitrate concentration exhibited a maximum in degree of grafting at 0.01 M. Also observed was that the change in acetic acid content in reaction media gave a maximum in degree of grafting at 7% acetic acid in water. Degree of grafting was increased generally with increase in acrylamide concentration reaction time and reaction temperature. When acrylonitrile monomer was used for grafting,different results were obtained. Addition of nitric acid was more effective in enhancing the degree of grafting than the addition of acetic acid.Generally the grafting of acrylonitrile to silk fibroins was less efficient than the grafting of acrylamide. The portion of grafted silk fibroins insoluble in Lowe's reagent exhibited the IR absorption bands characteristics to both vinyl polymers and silk fibroins, indicating the grafting of vinyl monomers to silk fibroins. To examine the molecular weight of graft vinyl polymer, a sample of grafted silk was hydrolyzed by 10% sodium hydroxide. Viscosity measurements indicated that the molecular weight of the graft polymer was in the range of 105.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.323-327
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• 2006

The Formation of acrylamide was studied in Maillard model reaction systems based on asparagine-glucose. The mixture of asparagine and glucose in equal molar ratio, and then heated at 125, 150, 175 and $200^{\circ}C$ for 10, 20 and 30 minute, respectively. The reaction products were extracted with ethyl acetate and methanol, and then isolated and detected on FFAP capillary column and HP-5MS 5% phenyl methyl siloxane column by using GC/MS. Acrylamide was detected only from methanol extracts and on FFAP capillary column, at retention time 23.53 min., and the detection limit was 4.6 ng. Acrylamide content mainly increased with increasing temperature and processing time till $175^{\circ}C$, therefore, maximal acrylamide formation occurred at $175^{\circ}C$ for 10 minute ($116{\mu}g/g$), while, above $175^{\circ}C$, higher temperatures or prolonged processing times caused a decrease of acrylamide levels, finally disappeared at $200^{\circ}C$ for 30 minute. Three major compounds were identified as 1,3-dihydroxypropanone, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyrane-4-one and 5-hydroxymethylfurfural, and three minor compounds also as 5-methylfurfural, 2-acetylpyrrole and N,N-dimethylcyclohexamine, from ethyl acetate or methanol extracts on FFAP or HP-5MS capillary column.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.744-750
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• 2017

Acrylamide is a probable human carcinogen and can be formed during frying of starchy foods. The objective of this study was to investigate the effects of acrylamide reduction in storage potato chips by fermentation of Bacillus subtilis and compare its usefulness with four different cultivars of storage potatoes (Goeun, Atlantic, Saebong, and Jinsun). Potato slices were fermented by B. subtilis at $37^{\circ}C$ for 0, 2, and 4 h and fried at $180^{\circ}C$ for 115 s. The total sugar contents of the fermented potato slices did not change compared to the control. However, reducing sugar contents increased in the fermentation solution containing potato slices. Asparagine contents of Saebong and Jinsun potato slices decreased with fermentation time. Color values of the fermented potato chips were improved compared to those of non-fermented potato chips. The highest $L^*$ value was found in Saebong (57.4), followed by Goeun (56.7), Jinsun (52.5), and Atlantic (48.8) after 4 h of fermentation. Potatoes stored for 240 days generated considerable amounts of acrylamide, ranging from 4.99 to 10.38 ppm, after frying. Four hours of fermentation reduced acrylamide formation in all potato chips. The lowest acrylamide content was found in Saebong (0.77 ppm), followed by Jinsun (1.21 ppm), Goeun (1.76 ppm), and Atlantic (4.09 ppm). In conclusion, fermentation of storage potatoes by B. subtilis can effectively lower acrylamide formation during frying of potato chips.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.857-862
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• 2004

Effects of frying temperature and time, presoaking in distilled water, various pH buffer solutions, and storage temperature of french fries on acrylamide formation were investigated. Acrylamide concentration in french fries increased as frying temperature and time increased. Presoaking of raw potatoes in distilled water reduced acrylamide formation compared to those without presoaking. Acrylamide formation of fried potatoes after presoaking at $60^{\circ}C$ for 45 min was about 16% of that without presoaking. Presoaking treatment of raw potatoes in various buffer solutions showed acrylamide concentrations of french fries from potatoes presoaked in acidic buffer solutions were lower than those from potatoes presoaked in neutral to alkaline buffer solutions. Acrylamide concentration of potatoes stored at refrigerator temperature was much higher than those stored at room temperature.

• The Korean Journal of Zoology
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• v.33 no.4
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• pp.461-467
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• 1990

To investigate the neurological effect of acrylamide, whole brain of Intoxicated mouse induced early hindlimbs ataxia was examined by using the methods of SDS-PAGE and two-dimensional electrophoresis. In the gel patterns by SDS-PAGE, when the patterns of each group were compared relatively, there were no remakable changes but in the patterns of 2D-PAGE, some protein alterations were observed. Especially, the spots containing 20 (14,500, 5.64) and 21 (19,900, 6.78) were disappeared, and the spots 9 (31,300, 5.82), 11 (31,300, 5.36) and 19 (16,400, 5.42) showed marked decrease relatively in the case of treatment group. Among these changed spots, the spot 20 (14,500, 5.64) showed higher quantity than that of control group but several spots containing the spots 11 (31,300, 5.36), and 19(16.400, 5.42) were identical or equal to those of control In quantity in the case of recovery group. It seems that acrylamide might already inhibit the brain protein synthesis mechanism at the time of onset of distal neuropathy by participation in the protein metabolism so as to impair the brain regulation ability followed by a malfunction of mouse central nervous system (CNS) and recovery is gradually progressed with the dose and duration dependence after the cessation of acrylamide administration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.460-465
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• 2016

The market for potato chips has expanded due to increased consumption of seasoned potato chips. However, the deep-frying process facilitates development of a browning color and formation of acrylamide. The objective of this work was to minimize browning color and acrylamide formation by fermentation prior to deep-frying. Potato slices were fermented by using three Bacillus strains, B. licheniformis (BL), B. methylotrophicus (BM), and B. subtilis, for 6 h at $30^{\circ}C$. In all fermentation groups, contents of total sugars in potato slices decreased. The color of fermented potato chips improved compared to the control. BM potato chips showed the best color values (76.33 in L value, 5.67 in a value, and 34.79 in b value). All fermentation processes reduced levels of acrylamide in deep-fried potato chips. Fermentation of potato slices for 2 h by BL reduced up to 96.1% acrylamide content. It was concluded that the fermentation process can positively affect color development and acrylamide formation.

• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.39-45
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• 1993

The effect of concentrations of phosphate buffer and acrylonitrile, pH, and various salts on the operational stability of the immobilized cells of Brevibacterium CH2 in a packed bed reactor were investigated. The effects of salts and carriers on the swelling of the immobilized beads during hydrolysis in a columnreactor were also investigated. Immobilization of the cells in Ba-alginate was more desirable than those in polyacrylamide and Ca-alinate for the swelling of the immobilized beads and the desired quality of the acrylamide produced. High quality acrylamide was produced using the Ba-alginate beads in a recycle fed-batch reactor without using an isotonic substrate. The conversion yield was nearly 100％, including a trace amount of acrylic acid produced as a by-product.