• Journal of Ecology and Environment
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• 제46권2호
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• pp.136-143
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• 2022

Background: In northern Thailand, the longan flower is the principal nectar source for honey production. Microorganisms play a critical function in the agricultural ecology. The morphological characteristics of fungal species found in longan pollen were studied. Aspergillus spp. were found to be invertase-producing strains and were employed in the longan syrup production process. The purpose of this study was to evaluate the effects of invertase-added longan syrup on the adult honey bee population numbers that were fed by this syrup for 16 weeks. Results: Different fungal species were found in longan pollen samples. Aspergillus was the main genus, with three predominant sections: Nigri, Flavi, and Terrei. Other isolated species were Trichoderma spp., Rhizopus spp., Neurospora spp., Chaetomium spp., Fusarium spp. and Penicillium spp. However, Aspergillus spp. is the only fungal species that produces the enzyme invertase. The invertase-producing strains belonging to the Aspergillus section Nigri were found to be A. niger LP5 with an optimum activity at pH 6.0 and 60℃. When A. niger LP5 invertase was used for longan syrup processing, the highest levels of glucose (3.45%) and fructose (2.08%) were found in invertase added longan syrup (C), while fresh (A) and boiled longan syrup (B) had lower contents of both sugars. The sucrose content was detected in (A) at 4.25%, while (B) and (C) were at 4.02% and 3.08%, respectively. An appropriate amount of sugar to feed and maintain the honey bee population was considered. The data showed no statistically significant differences between the two selected forms of longan syrup compared to the sugar syrup examined by the adult honey bee population. Conclusions: The main species of isolated fungi from longan pollen were Aspergillus spp. The discovery of an invertase-producing strain of A. niger LP5 has enabled its application for enzyme utilization in the invert sugar preparation process. The adult worker bee populations fed by longan syrup from both boiled and invertase-added sources showed an increasing trend. Artificial syrup made from longan fruit to feed honey bees when natural food sources are limited can be applied.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.318-322
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• 2006

알칼리와 고온에 대한 내성을 가진 invertase를 대량생산하기 위하여 호알칼리성이며 고온성 세균인 Bacillus sp. TA-11의 세포내 invertase유전자를 pUC 19벡터를 이용하여 E. coli HB101에 클로닝 시키고 발현시켜 invertase를 강력하게 생산하는 재조합 E. coli (pYC17)를 얻었다. 재조합 E. coli(pYC17)를 이용한 invertase 생산 최적조건을 검토한 결과 E. coil(pYC17)를 0.25% sucrose, 0.5% yeast extract, 0.1% $K_2HPO_4$와 0.1% $KH_2PO_4$을 함유한 SY배지(초기 pH 9.0)에 접종하여 37$^{\circ}C$에서 9시간 배양하였을 때 친주보다도 많은 47.7 U/ml-cell free extract의 invertase가 생산되었다.

• KSBB Journal
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• 제8권4호
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• pp.313-319
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• 1993

다공성 실리카표변에 폴리에틸렌이민과 글루타르 알데히드로 전화당 효소를 고정화시키고 자당과 에 탄올로부터 메틸 프룩토시드를 합성한 결과 다음과 같은 결론을 얻었다. 다공성 설리카를 폴리에틸렌이 민으로 표면처리하여 얻어진 고정화 담체는 그 다공 성 구조와 표면화학적 특성이 효소의 고정화에 적합 하여 전화당 효소에 대한 고정화 함량 120mg/g, 활 성도 lOOD/mg을 얻어 배당체의 합성반응에서 필요 로 하는 고정화 촉매를 제조할 수 었었으며 고정화 담체 표변에 형성된 폴리에틸렌이민 피막은 효소 부근에 친수성 분위기를 유지하여 높은 효소활성을 나 타내었고 에틸 프룩토시드가 효소에 접근하여 가수 분해되는 반응을 억제하여 메틸 프룩토시드의 수율 과 농도를 크게 증가시켰다. 자당과 메탄올 수용액 으로부터 메틸 프룩토시드를 합성한 결과, 자당 농도 O.291mol/l , 메탄올 농도 30%(v/v), 반응온도 $25^{\circ}C$, pH 4.8, 효소활성도 2U/ml일 때 자당의 전화 율 91.2%, 에틸 프룩토사드 농도 27.0g/l , 그 평균 수율 55.9%을 얻었으며, 위의 연구결과로부터 고정화 효소에 의한 배당체의 합성반응이 연속생산공정 으로 연구개발 될 수 있을 것으로 기대된다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.74.2-74
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• 2003

Arabidopsis infected with beet curly top virus (BCTV) has the systemic symptoms like stunting of Plant growth, curling of leaves and shoot tips, and callus induction. The regulation of sucrose metabolism by BCTV infection is essential for obtaining the energy source in the process of virus replication and symptom development. Sucrose metabolism-associated gene expression and biochemical enzyme activity were analyzed with the rossette leaves and inflorescencestems of BCTV infected Arabidopsis by the time course of 1, 7, 14, 21 day postinoculation. The expression of invertase and sucrose synthase genes ( encoding sucrose-cleaving enzymes )was increased and reversely the level of Atkin10a ( sucrose non-fermenting gene ) was decreased, resulting by semi-quantitative reverse transcription polymerase chain reaction. The biochemical analysis of invertase and sucrose synthase activity was performed. The activity of neutral invertase in the inflorescence stems was elevated remarkably. The photosynthetic response in the source of sucrose metabolism was consistent with the down-regulation of ribulose 1,5 bisphosphate carboxylase gene, and lower activity than mock-inoculated plants. The levels of genes pertaining to the cell cycle, hormone, and biotic stress-related pathway showed an increase or a decrease dependent on viral symptoms. Therefore, sucrose sensing by BCTV infection can regulate the expression of sucrose metabolism-related key enzymes such as invertase and Atkin10a, and these gene products might influence to symptom development.

• 한국응용곤충학회지
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• 제17권3호
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• pp.139-142
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• 1978

적성병균에 감염된 배나무 잎에서 건전부위, 병반인접부위 및 병반부위별로 몇가지 가수분해효소의 활성을 측정한 결과는 다음과 같다. 1. Cellulase (Cx), Invertase 및 $\beta-amylase$의 활성은 감염부위에서 보다 건전부위에서 더 높았고 모두 pH 7.0부근인 중성측에서 최대활성이 나타났다. 2. Pectinmethylesterase, Polygalacturonase 및 Phosphatase의 활성은 병반인접부위에서 높았다. 3. Pectinmethylesterase의 활성은 건전부위와 병반 및 그인접부위 간에 pH에 따라 심한 활성차리가 인정되었다.

• 원예과학기술지
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• 제34권6호
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• pp.898-911
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• 2016

Sugars play many important roles in plant metabolism and directly influence fruit quality. The effects of two edible coatings, 2% calcium chloride and 1% pullulan, on sugar metabolism in postharvest Huangguan pear fruit were investigated during cold storage. The respiration rate, sugar content and composition, sucrose metabolism enzyme activities [acid invertase (AIV), neutral invertase (NI), sucrose synthase (SS), and sucrose phosphate synthase (SPS)] and expression of the AIV gene were analyzed during storage at $0^{\circ}C$ for 210 days. Coating treatments slowed the decrease of sucrose and hexose, the respiration rate, and the activities of AIV, NI, SS and SPS, thus maintaining high total soluble solids (TSS) and titratable acid (TA) contents in the fruit. There were no significant differences in AIV expression or activity between the treated and control groups of fruits. Both of the coatings could inhibit the activities of sucrose-cleaving enzymes, thus slowing the decrease of sugar content and maintaining high fruit quality during cold storage.

• 한국식품영양과학회지
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• 제23권4호
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• pp.680-685
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• 1994

Total nitrogen content, proline, free amino acids, sugars, invertase and diastase activities in native bee-honey (NBH) and foregin bee-honey (FBH) harvested from our different areas of Kangwon , Korea were determined. The total nitrogen contents of NBH and FBH were 0.077$\pm$0.033mg% and 0.055$\pm$0.022mg%, respectively. Proline content in NBH was 42$\pm$10mg% and waqs found to be much lower than that in FHB. Phenylalanine and proline were major free amino acids both in NBH and FBH . The content of total free amino acid in FBH were twice as much as that in NBH , however isomaltose content in NBH were almost two times more than that in FBH. Other sugars including fructose, glucos , sucrose and maltose were also analyzed. No differences were found between NBH and FBH in invertase activities, but comparing to these of FBH ,lower values of diastase activity in NBH were observed.

• Applied Biological Chemistry
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• 제27권2호
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• pp.112-118
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• 1984

설탕 가수분해효소인 invertase를 칼슘 알지네이트젤에 고정화시켰다. 고정화된 입자는 균일한 크기와 모양을 가졌으며 컬럼 충진에 사용 할수 있는 좋은 기계적 강도를 보였다. 최적 효소 활성을 얻기 위하여 알지네이트 젤의 농도, 염화칼슘의 농도, 그리고 염화칼슘 입자의 반응 시간에 따른 영향 등을 조사하였다. 그 결과 2% 알지네이트 젤을 0.2M 염화 칼슘에 2시간 반응시켰을 때 가장 좋은 활성을 보였으며 이해 68%의 효소 수율을 나타냈다. 최적화된 조건에 의해 제조한 고정화 효소는 143mM의 km, 최적 pH는 4.5를 보였으며 $55^{\circ}C$에서 높은 효소 활성 및 열 안정성을 보였다. 젤의 효소 허용 부하량은 20ml 당 150mg이었고 6일동안 컬럼을 통한 설탕의 연속 가수분해에서는 효소 활성에 어떤 감소도 보이지 않았다.

• Applied Biological Chemistry
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• 제27권1호
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• pp.45-51
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• 1984

K. marxianus inulase는 inulin 배지에서 생성이 증가되고, glucose나 fructose의 탄소원에 의하여 생성이 억제되는 유도효소로서 배양중 최대의 효소활성은 생장곡선의 정지기 초기에 나타났다. 부분 정제된 inulase는 inulin, sucrose, raffinose를 가수분해하며, 이 효소의 inulin과 sucrose에 대한 최적 pH와 최적온도는 동일하게 4.0과 $55^{\circ}C$였으며, 두 기질에 대하여 $Hg^{++}$와 $Ag^{+}$ 이온은 효소활성을 똑같이 크게 억제하는 반면, EDTA에 대해서는 영향이 없었다. 또한 이 효소의 특징은 invertase 활성도 동시에 가지고 있는 endo-type이며, inulin과 sucrose에 대한 Km 값은 각각 $1.2{\times}10^{-2}M$과 $1.3{\times}10^{-4}M$이었다.

• 미생물학회지
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• 제13권3호
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• pp.85-90
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• 1975

Crude cellulases freshly prepared from cultures of Aspergillus niger, Prnicillum motatum, Trichoderma vride 16273 and Trichoderma viride 16374 were assayed on 4 different substrates including Na-CMC, cellulose powder, starch and sucrose. Enzyme prepared from A. niger contained highly active hydrolytic enzymes of the 4 substrates assayed. P. notatum [yielded relatively lower amount of cellulase but the extracts were also highly reactive on starch and sucrose. Trichoderma viride 16274 yielded very little cellulase and invertase, but the extracts showed a high degree of amylase activity. Trichoderma viride 16374, however, yielded collulase comparable to that of Penicillium notatum, but lower activities of amylase and invertase were seen. Commercial cellulases prepared from Penicillium notatum (cellulase[K]) and Trichoderma viride(cellulase[J]) indicated enzyme activities closely parallel to the crude enzymes freshly prepared from fungus cultures. The optimum pH's of cellulolytic activities of cellulase[K] and cellulase[J] were 4.0 and 5.0 respectively. The optimum temperatures of the cellulolytic activities of cellulase[K] and cellualse[J] were 4.0 and 5.0 respectively. The optimum temperatures of the cellulolytic activities of cellulase [K] and cellulase [J] were $60{\circ}C$ and $50{\circ}C$ respectively. Assuming the average molecular weight of Na-CMC is about 115,000, the Km values of cellulase [K] and cellulase[J] were found to be $3.3{\times}10^{-5}/nM$ and $3.3{\times}10^{-4}/nM$ respectively.