• 한국식품영양학회지
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• 제9권4호
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• pp.430-433
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• 1996

딸기의 2차대사에 관여하는 phenylalanine ammonia-lyase는 풍미나 색소, 향기 등에 큰 영향을 미치며 숙도 측정지표로 여겨진다. phenylalanine ammonia-lyase는 숙성 전단계에 걸쳐 활성을 나타내기는 하나 완숙기와 과숙기에 그 활성이 뚜렷이 증가하였다. 이는 딸기의 숙성과 더불어 de novo 합성이 되기 때문으로 보인다. 분자량은 겔 크로마토그래피로 260,000으로 나타났다.

• Food Science and Biotechnology
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• 제18권2호
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• pp.494-499
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• 2009

To improve phenylalanine ammonia lyase (E.C.4.3.1.5-PAL) activity in recombinant Escherichia coli, Some approaches for improving phenylalanine ammonia lyase (PAL) activity in recombinant E. coli were developed following preliminary studies by means of response surface method. The results shown that permeabilization with combination of Triton X-100, cetyl trimethyl ammonium bromide (CTAB), and acetone enriched cellular recombinant PAL activity significantly, which improved over 10-fold as compared with the control (untreat cell), as high as 181.37 U/g. The optimum values for the tested variables were Triton X-100 0.108 g/L, CTAB 0.15 g/L, and acetone 45.2%(v/v). Furthermore, a second-order model equation was suggested and then validated experimentally. It was indicated that addition of surfactants and organic solvents made the cells more permeable and therefore allowed easier access of the substrate to the enzyme and excretion of the product, which increased the rate of transport of L-phenylalanine and trans-cinnamic acids. These improved methods of PAL activity enrichment could serve as a rich enzyme source, especially in the biosynthesis of L-phenylalanine.

• Preventive Nutrition and Food Science
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• 제2권4호
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• pp.354-359
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• 1997

Optimal cultivation conditions for the production of phenylalanine ammonia-lyase(PAL) from Rhodotorula aurantiaca K-505 were selected, and the kinetic parameters of the produced PAL were determined. The most suitable carbon and nitrogen sources were glucose and tryptone, respectively. The strain expressed PAL constituttively when using the optimized semi-complex media. High cell density culture could be critical for maximal production of PAl since the PAL ynthesis was growth associated. maximum PAL activity was observed at initial pH 6.0. although the ll growth was not markedly affected by temperature between 22 and 28$^{\circ}C$, the cells yielded the maximum PAL activity when cultivated at 22$^{\circ}C$. The maximum activity for deamination of L-phenylalnine to trans-cinnamic acid was observed around pH 8.8. The PAL activity gave the maximum at 45$^{\circ}C$, and greatly decreased at higher than 5$0^{\circ}C$. Activation energy({TEX}$E_{a}${/TEX}) calculated from Arrhenius equation was 6.28 kcal/mol in the range of 22$^{\circ}C$ to 4$0^{\circ}C$. A oolf plot showed that the enzyme reaction follows Michaelis-Menten equation, whose {TEX}$K_{M}${/TEX} and {TEX}$V_{max}${/TEX} values were 4.65$\times${TEX}$10^{-3}${/TEX} M and 0.89$\mu$ mol/mg-min respectively.

• 한국환경과학회지
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• 제14권12호
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• pp.1093-1102
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• 2005

Effects of abscisic acid(ABA) and temperature on the anthocyanin accumulation and phenylalanine ammonia Iyase(PAL) activity were investigated in seedlings of Arabidopsis thaliana. In time course study, exogenous application of ABA $(50-1000\;{\mu}M)$ led to a noticeable increase in anthocyanin pigments which persisted over the following 5 days. Anthocyanins increased in concert with the chlorophyll loss. The activity of PAL, a key enzyme in the phenylpropanoid pathway, increased on exposure to ABA and reached maximum on the 4th day, This result shows that anthocyanin synthesis and PAL activity have a close physiological relationships. In the effects of temperatures ($10^{\circ}C,\;17^{\circ}C,\;25^{\circ}C$and $30^{\circ}C$) on anthocyanin accumulation and PAL activity in seedlings, a moderate-low temperatures ($17^{\circ}C$) enhanced both anthocyanin content and PAL activity, whereas elevated temperatures ($30^{\circ}C$) showed low levels of anthocyanin and PAL activity, suggesting a correlation between temperature-induced anthocyanin synthesis and the accumulation of PAL mRNA. Simultaneous application of ABA with temperatures Induced higher anthocyanin synthesis and PAL activity in seedlings than ABA or temperature stress alone. Moderate-low temperature with ABA exposure elicited the maximal induction of anthocyanin synthesis and PAL activity. Therefore, ABA treatment significantly increased thermotolerance in .A. thalinan seedlings. Ethephon and ABA showed similar mode of action in physiological effects on anthocyanin accumulation and PAL activity. Our data support that anthocyanins may be protective in preventing damage caused by environmental stresses and play an important role in the acquisition of freezing tolerance.

• Food Science and Biotechnology
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• 제18권4호
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• pp.954-958
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• 2009

Effects of controlled- and uncontrolled-pH operations on phenylalanine ammonia lyase (PAL) production by a recombinant Escherichia coli strain were investigated at uncontrolled-pH ($pH_{UC}$) and controlled-pH ($pH_C$) of 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, and 8.5 in bioreactor systems. The results showed that the recombinant PAL activity was improved significantly by controlled pH strategy. Among the $pH_C$ operations, the highest PAL activities were obtained under $pH_C$ 7.5 strategy where cell mass ($OD_{600\;nm}$) and PAL activity was 1.3 and 1.8 fold higher than those of $pH_{UC}$, respectively. The maximum PAL activity reached 123 U/g. The $pH_C$ 7.5 strategy made recombinant plasmid more stable and therefore allowed easier expression of PAL recombinant plasmid, which increased PAL production. It was indicated that the new approach (controlled-pH strategy) obtained in this work possessed a high potential for the industrial production of PAL, especially in the biosynthesis of L-phenylalanine.

• Plant Biotechnology Reports
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• 제5권4호
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• pp.301-308
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• 2011

This study tested the relative and combined efficacy of ShPx2 and ShPAL transgenes by comparing Nicotiana tabacum hybrids with enhanced levels of $_L$-phenylalanine ammonia lyase (PAL) activity and cationic peroxidase (Prx) activity with transgenic parental lines that overexpress either transgene. The PAL/Prx hybrids expressed both transgenes driven by the 35S CaMV promoter, and leaf PAL and Prx enzyme activities were similar to those of the relevant transgenic parent and seven- to tenfold higher than nontransgenic controls. Lignin levels in the PAL/Prx hybrids were higher than the PAL parent and nontransgenic controls, but not significantly higher than the Prx parent. All transgenic plants showed increased resistance to the necrotrophs Phytophthora parasitica pv. nicotianae and Cercospora nicotianae compared to nontransgenic controls, with a preponderance of smaller lesion categories produced in Prx-expressing lines. However, the PAL/Prx hybrids showed no significant increase in resistance to either pathogen relative to the Prx parental line. These data indicate that, in tobacco, the PAL and Prx transgenes do not act additively in disease resistance. Stacking with Prx did not prevent a visible growth inhibition from PAL overexpression. Practical use of ShPAL will likely require more sophisticated developmental control, and we conclude that ShPx2 is a preferred candidate for development as a resistance transgene.

• Current Research on Agriculture and Life Sciences
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• 제20권
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• pp.65-70
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• 2002

본 연구는 allelopathic potential을 지닌 벼의 교잡종을 포장에서 재배하여 그 식물체의 잎을 생물검정에 이용하여 allelopathy 효과 유무를 검정하고, 생물검정으로 선발된 교잡종을 대상으로 phenolic compounds를 조사하여 allelochemical로써의 가능성을 확인하고 나아가 phenolic compounds 생합성에 관여하는 효소의 활성 측정과 이 효소의 작용에 의해 유도되는 phenolic compounds를 구명한 결과는 다음과 같다. 1. 포장상태에서 피를 대상으로 생물검정을 실시한 결과 양친으로는 Kouketsumochi, Woo co chin yu에서 공통적으로 90% 이상의 높은 피뿌리 생장 억제율을 보였고, 교잡종에서는 Kouketsumochi/Woo co chin yu, Dongjinbyeo/Kouketsumochi, Dongjinbyeo/Woo co chin yu 조합에서 80% 이상의 높은 억제율을 나타냈다. 2. Kouketsumochi의 PAL 활성은 protein 1kg당 $63.46{\mu}kats$로 타 공시품종보다 높았다. 또한 Kouketsumochi와의 교잡종도 타교잡종보다 높은 것으로 나타났다. 3. Kouketsumochi의 cinnamate 함량은 생체중 1g당 $2.64{\mu}g$으로서 다른품종이나 교잡종보다 2~5배 높았고, Kouketsumochi와의 교잡종도 타교잡종보다 높았다.

• 생명과학회지
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• 제15권2호
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• pp.298-303
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• 2005

포도 '거봉'의 착색을 조장하기 위해 적절한 ABA의 처리시기와 처리 횟수를 알아보기 위하여 본 실험을 수행한 결과 다음과 같은 결과를 얻었다. PAL 효소의 활성은 변색기 처리구와 변색기 10일 후 처리구에서 활성이 높은 것으로 나타났으며, 변색기 10일후 처리구가 변색기 처리구보다 약간 더 높은 효소 활성을 나타냈다. 안토시아닌 함량은 각 처리구 공히 생육기간 동안 계속 증가하는 경향을 보였고, 모든 ABA 처리구는 무처리구에 비해 훨씬 높은 안토시아닌 함량을 나타내었으며, 변색기 10일후 처리구에서 가장 높은 안토시아닌 함량을 나타내었다. 가용성당 함량에 있어서 과당과 포도당만이 검출되었으며, 처리구간에 함량의 차가 그다지 크지 않았다. 처리 횟수에 있어서 PAL 효소의 활성은 각 처리구 공히 증가하다가 감소하는 경향을 보였으며, 2회 처리구는 변색기 10일후의 2회째 처리 이후에도 급속한 PAL 효소 활성 증가가 이어져 최종수확기에서도 비교적 상당히 높은 효소 활성을 보였다. 변색기와 변색기 10일 후의 2회 처리구에서 안토시아닌 함량 증가가 가장 높아 최종수확기에 가서는 무처리구에 비해 5배 이상, 1회 처리구에 비해서는 2배정도 많았다. 1회 및 2회 ABA 처리구 모두 과당과 포도당 함량 공히 무처리구에 비해 약간 높은 경향을 나타냈지만 그다지 큰 차이는 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.1006-1012
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• 2017

Objective: This study was conducted to investigate effects of zinc (Zn) bearing palygorskite (ZnPal) supplementation on growth performance, hepatic mineral content, and antioxidant status of broilers at early age. Methods: A total of 240 1-day-old Arbor Acres broiler chicks were allocated into 5 treatments with 6 replicates of 8 chicks each. Birds in 5 treatments were fed a basal diet supplemented with 0 (Control group; Analyzed Zn content: 81 mg/kg), 20, 40, 60, and 80 mg/kg Zn as ZnPal for 21 days, respectively. Blood, liver and intestinal mucosa were collected at 21 days of age. Results: Treatments did not affect growth performance of broilers during the 21-day study (p>0.05). The contents of hepatic Zn and magnesium (Mg) were linearly increased (p<0.001) by ZnPal supplementation. ZnPal inclusion linearly (p = 0.007) reduced malondialdehyde (MDA) concentration in serum. The activity of total superoxide dismutase (T-SOD) in liver increased linearly (p = 0.001) with concentration of ZnPal in diet. ZnPal inclusion linearly (p = 0.036) and quadratically (p = 0.005) increased T-SOD activity, and linearly (p = 0.012) increased copper/zinc superoxide dismutase (Cu/Zn SOD) activity in jejunal mucosa. The maximum responses of hepatic and jejunal antioxidant enzymes activities (T-SOD and Cu/Zn SOD) were found when supplementing the basal diet with 60 mg/kg Zn as ZnPal. Furthermore, ZnPal supplementation quadratically (p = 0.001) increased Cu/Zn SOD activity in ileal mucosa, and its maximum activity was observed in the diet supplemented with 20 mg/kg Zn as ZnPal. Conclusion: ZnPal supplementation did not alter growth performance of broilers. Dietary ZnPal inclusion could increase concentrations of hepatic trace minerals (Zn and Mg) and inhibit lipid peroxidation by reducing serum MDA accumulation, with the optimal dosage of Zn from ZnPal being 80 mg/kg diet (analyzed Zn content in the diet: 165 mg/kg), and 60 mg/kg Zn as ZnPal (analyzed Zn content in the diet: 148 mg/kg) was the optimum dosage for broilers to achieve maximum antioxidant enzyme activities.

• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.622-632
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• 2020

Phenylalanine ammonia-lyase (PAL) catalyzes the reversible deamination of phenylalanine to cinnamic acid and ammonia. Algae have been considered as biofactories for PAL production, however, biochemical characterization of PAL and its potency for myristicin biotransformation into MMDA (3-methoxy-4, 5-methylenedioxyamphetamine) has not been studied yet. Thus, PAL from Anabaena flos-aquae and Spirulina platensis has been purified, comparatively characterized and its affinity to transform myristicin was assessed. The specific activity of purified PAL from S. platensis (73.9 μmol/mg/min) and A. flos-aquae (30.5 μmol/mg/min) was increased by about 2.9 and 2.4 folds by gel-filtration comparing to their corresponding crude enzymes. Under denaturing-PAGE, a single proteineous band with a molecular mass of 64 kDa appeared for A. flos-aquae and S. platensis PAL. The biochemical properties of the purified PAL from both algal isolates were determined comparatively. The optimum temperature of S. platensis and A. flos-aquae PAL for forward or reverse activity was reported at 30℃, while the optimum pH for PAL enzyme isolated from A. flos-aquae was 8.9 for forward and reverse activities, and S. platensis PAL had maximum activities at pH 8.9 and 8 for forward and reverse reactions, respectively. Luckily, the purified PALs have the affinity to hydroaminate the myristicin to MMDA successfully in one step. Furthermore, a successful method for synthesis of MMDA from myristicin in two steps was also established. Gas chromatography-mass spectrometry (GC-MS) analysis was conducted to track the product formation.