• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1800-1812
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• 2005

Aquaculture pollution is a major concern among the entrepreneurs, farmers and researchers. Excess discharge of phosphorus and nitrogen into the water bodies is the principal pollutant responsible for this. Plant-based feed ingredients due to its high phytic acid content enhances both nitrogen and phosphorus discharge thereby increasing the pollution level. Dietary phytase treatment is probably the best answer to address this problem. This review explains the nature and properties of phytate, its interactions with other nutrients and the application of phytase in aquafeed to reduce the pollution. This review also covers the different biotechnological aspects for lowering the phytic acid level in the common aquafeed ingredients, as an alternate approach to controlling the pollution level. Some of future research needs have also been highlighted to attract the attention of more researchers to this area.

• Applied Biological Chemistry
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• 제46권4호
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• pp.291-298
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• 2003

축산폐수가 방류되는 단위동물 밀집사육장 인근의 하천수로부터 phytase를 생산하는 세균들 중 활성이 가장 우수한 균주를 분리하여, Pseudomonas fragi Y9451로 동정, 명명하였다. 탄소원으로 fructose를 첨가할 경우에 phytase의 생산능이 가장 우수하였고, 배지에 7% 첨가할 경우에 72시간 배양 후 효소활성이 1,078 mU/ml로 최대의 phytase 생산능을 보였다. 또한, 질소원으로는 nutrient broth(NB)가 적합하였으며, NB를 3%의 농도로 첨가할 경우에 96시간 배양 후 효소활성이 1,425 mU/ml까지 향상되었다. 인산원인 $KH_2PO_4$, phytate는 첨가 농도가 높을수록 phytase 생산은 억제되었으며, 무기염으로 $MgSO_4$와 $CaCl_2$를 첨가하는 경우는 첨가농도와 상관없이 phytase의 생산을 현저히 억제하였다. 산업생산을 목적으로 하는 scale-up에 있어서의 통기교반 효과는 phytase의 생산량에 큰 영향을 미치는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1442-1449
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• 2017

Objective: This study investigated the effect of microbial phytase supplementation on growth performance, tibia ash, plasma parameters, apparent ileal digestibility (AID) of amino acid (AA) and apparent digestibility of nutrients in Youxian Sheldrakes fed with low-phosphorus (P) cornsoybean diets. Methods: A total of 350 Youxian Sheldrakes (7d old) were randomly divided into 5 treatment groups: positive control (PC) group has adequate available P diet (0.42% and 0.38%, starter and grower), negative control (NC) group were deficient in available P (0.32% and 0.28%, starter and grower) and NC diet was supplemented with 3 levels of microbial phytase (500, 750, and 1,000 U/kg). Results: Dietary supplementation of phytase in NC diet improved the average daily gain, increased the levels of serum calcium (Ca), tibia Ca and P, AID of AA and apparent digestibility of energy and Ca in starter stage (p<0.05). There was an increased (p<0.001) in the utilization of P from 17.3% to 23.9%. Phytase supplementation (1,000 U/kg) has shown that the AID of His, Thr, Val, indispensable AA, Glu, Pro, and dispensable AA was higher (p<0.05) than that of NC. Moreover, phytase supplementation improved (p<0.05) serum and tibia Ca and P, AID of AA and apparent digestibility of dry matter, crude protein, energy, P and Ca, and reduced (p<0.05) feed to gain ratio (F/G) and the levels of serum alkaline phosphatase in grower stage. Likewise, an increase (p<0.001) in the utilization of P was noticed from 12.6% to 17.2%. Supplement phytase at 750 U/kg improved the AID of His, Thr, Asp, Cys, Pro, and Ser (p<0.05). Conclusion: The microbial phytase supplement could improve growth performance, AID of some AA and apparent utilization of other nutrients in Youxian Sheldrakes, and reduce excreta P load to environment.

• 한국가금학회지
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• 제36권3호
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• pp.247-255
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• 2009

본 시험은 육계 사료내 CDDGS의 첨가 수준과 phytase의 첨가유무가육계의생산성과영양소이용률에미치는영향을 구명하기 위해 수행하였다. 공시계는 시판 육계(Ross 308) 수컷 384수를 공시하였으며, CDDGS 4처리(0, 5, 10, 15%)와 phytase 2처리(0, 500 FTU/kg)의 $4{\times}2$ 복합 요인으로 총 8처리구, 처리구당 4반복, 반복당 12수를 체중별로 완전임의 배치하였다. 사양 시험이 끝난 육계는 체중이 유사한 개체를 12수씩 선별하여 1주간 동일 사료 급여 후 1주간 소화 시험을 실시하였다. 시험 사료는 육계 초기(0~2주), 전기(2~4주)와 후기(4~6)의 기본 사료에 CDDGS를 0, 5, 10 및 15% 첨가하였으며, ME가와 CP는 일정하게 유지하였다. 육계 사양기간 동안의 증체량과 사료 효율은 phytase 처리구에서 높게 나타났으며(P<0.05), 사료 섭취량은 모든 처리구간에 차이가 없었다. 일반성분의경우, 건물과조단백질의소화율은 전처리 구간에 차이가 없었으나, 조지방의 소화율은 CDDGS 5% 처리구에서 75.8%로 유의적으로 낮았다(P<0.05). 조섬유의 소화율은 CDDGS와 phytase 첨가구에서 소화율의 증가를 보였다(P<0.05). 필수 아미노산의 경우, iso-leucine, lysine, threonine 및 valine에서 소화율이 증가하였으며(P<0.05), 비필수 아미노산은 aspartic acid, proline, serine 및 tyrosine에서 소화율이 개선되었다(P<0.05). 따라서, 본 시험에서 육계 사료 내 CDDGS와 phytase 첨가는 육계의 생산성과 영양소 이용률을 개선시켰다.

• Fisheries and Aquatic Sciences
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• 제6권1호
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• pp.20-26
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• 2003

A bacterial strain was isolated from seawater to screen for phytase activities. A colony had the highest activity and was identified as an Escherichia coli strain. Using primers derived from E. coli acid phosphatase appA sequence, we cloned a 1,495 bp DNA fragment connected with the pGEM-T vector. It was over-expressed under lac promoter combined with its native promoter in E. coli $DH5\alpha$. The expression of the phytase gene occurred during late exponential growth and the intracellular phytase production was 16.9 units/ml. The yield of recombinant phytate was 412-fold higher than that of wild type E. coli K13.

• Journal of Microbiology and Biotechnology
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• 제15권4호
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• pp.745-748
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• 2005

A phytase from Aeromonas sp. LIK 1-5 was partially purified by ammonium sulfate precipitation and DEAE-Sephacel column chromatography. Its molecular weight was 44 kDa according to SDS-PAGE gel. Enzyme activity was optimal at pH 7 and at $50^{\circ}C$. The purified enzyme was strongly inhibited by 2 mM EDTA, $Zn^{2+},\;Co^{2+},\;or\;Mn^{2+}$, and activated by 2 mM $Ca^{2+}$. The K_m value for sodium phytate was 0.23 mM, and the enzyme was resistant to trypsin. The N-terminal amino acid sequence of the phytase was similar to that of other known alkaline phytases. The phytase was specific for ATP and sodium phytate, which is different from other known alkaline phytases. Based on the substrate specificity, the phytase may therefore be a novel alkaline phytase.

• 한국유기농업학회지
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• 제9권1호
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• pp.51-60
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• 2001

An experiment was carried out to evaluate the effects of adding phytase on nutrient digestibility in growing pigs. Three barrow pigs averaging 28.5$\pm$3.1kg of body weight were allotted to three treatments by 3$\times$3 latin square. Treatments included 1) com-soybean meal based-control diet and 2) and 3) control diet with phytase 500 and 1,000 unit. There were no effects of treatments on dry matter and nitrogen digestibility (P〉0.05). Ash, Ca and P digestibility in pigs fed diet with phytase were greater than those in pigs fed control diet(P〈0.05). An increased phosphorus intake was observed from pigs fed diet with treatments compared to that from pigs fed control diet. Pigs fed diet with adding phytase had improved P absorption compared to pigs fed control diet(P〈0.05). There was no significantly effect on fecal and urine excretion(P〈0.05). Ca intake was increased for pigs fed adding phytase compared to pigs fed control diet. No evident effect was observed on Ca fecal excretion among dietary treatments, however, urine excretion of pigs fed diet with treatments was decreased compared to pigs fed control diet. Cystine, isoleucine, tyrosine and phenylalanine digestibility of amino acid were greater for pigs fed diet with treatments than those for pigs fed control diet(P〈0.05). Asparagine, threonine, serine, methionine and leucine digestibility were improved for pigs fed with phytase 500 unit compared to pigs fed control diet. Lysine, histidine, arginine and other animo acids digestibility were higher for pigs fed diet with phytase than control diet, but there were no significant effects by the treatments(P〉0.05). In conclusion, the results of the experiments suggest that phytase supplementation in the diets could be a very beneficial strategy in environmental aspects.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1085-1091
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• 2009

A phytase with high activity at low temperatures has great potential for feed applications, especially in aquaculture. Therefore, this study used a degenerate PCR and TAIL PCR to clone a phytase gene from Erwinia carotovora var. carotovota, the cause of soft rot of vegetables in the ground or during cold storage. The full-length 2.5-kb fragment included an open reading frame of 1,302 bp and encoded a putative phytase of 45.3 kDa with a 50% amino acid identity to the Klebsiella pneumoniae phytase. The phytase contained the active site RHGXRXP and HD sequence motifs that are typical of histidine acid phosphatases. The enzyme was expressed in Escherichia coli, purified, and displayed the following characteristics: a high catalytic activity at low temperatures (retaining over 24% activity at $5^{\circ}C$) and remarkably thermal lability (losing >96% activity after incubation at $60^{\circ}C$ for 2 min). The optimal phytase activity occurred at pH 5.5 and ${\sim}49^{\circ}C$, and the enzyme activity rapidly decreased above $40^{\circ}C$. When compared with mesophilic counterparts, the phytase not only exhibited a high activity at a low temperature, but also had a low $K_m$ and high $k_{cat}$. These temperature characteristics and kinetic parameters are consistent with low-temperature-active enzymes. To our knowledge, this would appear to be the first report of a low-temperature-active phytase and its heterogeneous expression.

• 한국가금학회지
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• 제34권2호
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• pp.119-128
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• 2007

산란계의 생산성, 계란 품질, 질소와 인의 흡수량과 배설량 및 회장 소화율에 미치는 파이타제의 첨가 효과를 구명하고자 사료에 0, 300, 600 FTU/kg의 파이타제를 첨가하여 4주간 사양 시험 종료후 1주간 대사실험을 실시하였다. 공시동물은 산란율이 유사한 55주령 White Leghorn 산란계 162수$(1.6{\pm}0.3\;kg)$를 공시하였으며, 처리구는 첨가 수준에 따라 P0(대조구), P1(300 FTU/kg), P2(600 FTU/kg)의 3처리구로 나누고, 처리구당 6반복, 반복당 9수씩 완전임의 배치하였다. 산란율은 파이타제 첨가 수준에 따라 증가하였다. 계란 품질은 난중, 난각 두께, 하우유니트와 난황색 모두 처리구간에 차이를 보이지 않았으나(p>0.05), 난각 강도는 파이타제 처리구에서 4주째에 각각 3.86 $kg/cm^2$와 3.85 $kg/cm^2$로 나타나 파이타제 첨가에 따른 차이를 보였다(p<0.05). 질소 배설량과 흡수량은 처리구간에 차이가 없었으나(p>0.05), 인 배설량과 흡수량은 파이타제 첨가구에서 대조구에 비해 배설량이 크게 감소하고 흡수량은 증가하였다(p<0.05). 파이타제 첨가에 따른 영양소와 아미노산의 소화율은 조섬유, 조회분, 칼슘과 인, 필수 아미노산 중 lysine, methionine, phenylalanine, 비필수 아미노산 중 alanine, cystine, glutamic acid, glycine, tyrosine의 소화율을 유의적으로 증가시켰다(p<0.05). 이 실험 결과 산란계에 미생물유래 파이타제 급여는 산란율을 향상시키고, 인 배설량을 낮추며, 흡수량을 증가시키지만, 계란 품질에 미치는 영향이 없었고, 소화율에 대한 영향은 추후의 연구가 필요하다고 사료된다.

• Journal of Animal Science and Technology
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• 제51권2호
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• pp.177-182
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• 2009

산업용 균주인 Pichia pastoris에서 재조합 발현된 당화된 인간유래 MINPP (multiple inositol polyphosphate phosphatase) 효소는 기질 피틴태인(InsP6)에 대한 파이테이즈 효소활성을 나타내었고 탈당화시 그 효소활성이 30% 감소되었다. 그 효소의 기질 $InsP_6$에 대한 최적 pH 활성은 중성범위인 pH 7.4였다. 기질특이성 측면에서 인간 MINPP 효소는 para-nitrophenylphosphate (pNPP), ATP, ribose-1-phosphate (R-1-P)와 같은 유기인산화합물(organic phosphate conjugates)의 분해활성은 매우 낮은 대신, 기질 $InsP_6$를 효과적으로 분해하였고 특히 화학적 자극제인(chemical stimulator)인 1 mM 2-phosphoglycolate (2-PG)의 첨가에 따른 기질 2,3-bisphosphoglycerate (2,3-BPG)에 대한 효소활성이 2-PG를 첨가하지 않을때 보다 1.2배 증가되었지만 기질 $InsP_6$에 대한 효소활성에는 영향을 주지 않았다. 또한 2 mM $Mg^{2+}$ 이온과 100 mM $Cl^-$ 이온의 첨가는 MINPP 효소의 기질 2,3-BPG에 대한 효소활성에 역시 영향을 주지 않았다.