Drought stress is one of the major factors that reduce plant growth and productivity. This study was conducted to investigate the effect of exogenous acetic acid pretreatment on drought stress tolerance response in plants. Fourteen-day-old alfalfa plants were pretreated with 15 mM acetic acid, and then subsequently subjected to drought stress for 6 days. The fresh weight and relative water content in the leaves of acetic acid pretreated alfalfa plants were increased compared to the control group. The chlorophyll and carotenoid contents were slightly decreased in the acetic acid treatment. The H2O2 and proline contents were also significantly decreased in the acetic acid treatment. These results suggest that the scavenging mechanism of reactive oxygen species in alfalfa activated by acetic acid pretreatment is involved in conferring tolerance to drought stress.
To develop farm-made high effective vinegar, this study prepared apple vinegar using four kinds of acetic acid bacteria isolated from a natural fermentation liquid of ‘Cheongsoo’ grapes and analyzed vinegar samples fermented 93% apple juice and 7% alcohols at 30℃ for 20 days. To accomplish this, quality characteristics such as pH, total acidity, reducing sugar, organic acid, color, total polyphenol contents, and antioxidant activity contents were determined. The pH decreased while total acidity of all samples gradually increased during fermentation period. The vinegar with AP 21 strain tended to increase the total acidity quicker than other stains. Reduced sugar content remained high until the last fermentation day. Furthermore, reduced sugar contents of all vinegars increased as fermentation progressed by decomposing sucrose present in apples. When physiological activities were compared, apple vinegars fermented with AP 21 and 30 strains had higher total polyphenol and flavonoid contents than other samples. However, there was no significant difference in antioxidant activity between samples. These results indicate that strain 21 is the most suitable starter as acetic acid bacteria for producing farm-made vinegar.
농업 재배지 토양으로부터 auxin 생성세균 KSD16, KSD33 그리고 KSD36를 분리하였다. 분리 균주 KSD16, KSD33 그리고 KSD36 는 16S rRNA 유전자 계통분석을 통해 Arthrobacter 속으로 분류되 었다. 이들 균주는 R2A배지에 0.1% L-tryptophan를 첨가한 배지에서 28℃, 48 시간 배양한 결과, auxin 의 일종인 indole-3-acetic acid (IAA)를 204.4 mg L-1 생성하는 것으로 확인되었다. IAA 생성세균의 녹 두종자 발아에 미치는 영향을 확인한 결과, Arthrobacter 속 균주 KSD16, KSD33 그리고 KSD36 는 대조 군에 비해 뿌리길이와 발근수가 증가하였다. Arthrobacter 속 균주의 녹두 성장촉진 효과를 확인한 결과, 녹두의 발아율이 대조군보다 73.4 % 증가하는 특징을 나타내었다.
Salinity is a major abiotic stress for crop plants that cause reduced food production. The application of plant growth-promoting microorganisms can improve the adaptability of plants to biotic and abiotic stresses. Therefore, in the current study, we aimed to enhance the mitigation effects of artificially applied rhizobacterium Klebsiella variicola AY13 on salinity stress in Trifolium repens L. The results suggested that AY13 innately produced indole-3-acetic acid and accelerated the morphological adaptation of T. repens to salt stress conditions. Furthermore, AY13 promotes a Trp-dependent pathway for indole-3-acetic acid (IAA) production, as adding L-tryptophan (L-Trp) increased IAA production in pure culture. AY13 improved plant growth by maintaining relative water content and minimizing water loss in excised leaves. Moreover, AY13 inoculation significantly reduced the endogenous levels of abscisic acid and antioxidants such as glutathione and catalase. These results suggest that AY13 plays a crucial role in reprogramming stress-related metabolism and enhancing plant stress tolerance.
본 연구는 식물검역 분야에서 주요하게 사용되고 있는 메틸브로마이드 훈증제로 인해 발생하는 약해를 저감하기 위한 물질을 모델식물인 애기장대를 이용하여 스크리닝하였다. 사전연구를 통하여 메틸브로마이드 훈증제의 식물 독성 메커니즘으로 활성산소발생와 식물 성장 호르몬인 옥신의 식물체 내 분배억제효과가 발생하는 것을 바탕으로 하여, 약해 저감물질후보군으로 활성산소를 제거하는 역할을 하는 ROS scavenger 2종 (NAC, GSH)과 옥신을 훈증제 처리 전 애기장대에 처리한 후 약해의 저감 정도를 육안평가와 더불어 관련 유전자의 발현을 확인하였다. 연구 결과 메틸브로마이드에 의해 유도된 약해는 옥신보다는 활성산소를 저감시키는 물질후보군들에서 약해 저감효과가 나타났다. 이 중 GSH을 이용하여 농도구배하여 전처리하였을 때, 5 mM GSH 전처리 후 메틸브로마이드 훈증 시 약해 저감효과가 두드러졌다. GSH 전처리 시 식물체 내에 MBF1c와 HSP70 유전자 발현이 증가하는 것을 확인하였으며, 이는 메틸브로마이드 훈증으로 유도되는 약해를 방어하는 역할을 담당하였을 것이라고 평가된다. 따라서, 식물검역 훈증제 메틸브로마이드에 의해 발생하는 약해를 저감하는 데 GSH의 사용가능성을 평가하였으며, 이를 기반으로 다양한 식물체에 적용하여 수출입 시 약해로 인한 경제적 손실을 감소시킬 수 있기를 기대한다.
간장게장은 우리나라 전통 식품 중의 하나로 생 꽃게를 세척한 후 간장소스를 첨가하고 저온에서 숙성시켜 포장 하여 상업적으로 판매하고 있다. 하지만, 간장게장 제조 특성 상 열처리를 하지 않기 때문에, 간장게장의 미생물학적 품질을 유지하는데 어려움이 따른다. 따라서 본 연구에서는 원물 꽃게의 초기 미생물 저감화를 위해 여러 살균세척제의 효능을 비교하고 저장 중 간장게장 제품의 미생물학적 품질을 유지하기 위해 키토산의 항균 효능을 평가하였다. 먼저, 상온에서 생 꽃게를 염소수(50 mg/L), 과초산(40 mg/L), acetic acid (5%), lactic acid(5%)에 각각 10분간 침지시켜 일반세균수를 분석하였다. 결과를 살펴보면, 여러 살균세척제 중 5% acetic acid 세척이 생 꽃게에 존재하는 일반세균수를 약 1.5 log CFU/g까지 감소시켜 가장 효과적인 것으로 나타났다. 키토산 효능을 평가하기 위해 현재 상업적으로 제조되고 있는 간장게장(방법 1; 전해수 세척), 5% acetic acid로만 세척된 꽃게(방법 2), 5% acetic acid로 세척된 꽃게에 0.5%(방법 3)와 1%(방법 4)의 수용성 키토산이 첨가된 간장으로 제조된 간장게장을 각각 4oC와 12oC에서 최대 30일까지 저장하면서 일반세균수, 대장균군 및 대장균수를 측정하였다. 12oC에서 저장된 간장게장의 일반세균 수는 7일이 지났을 때 약 8 log CFU/g까지 증가하였다. 4oC의 경우, 1% 키토산이 첨가된 군(방법 4)에서 20 일 동안 약 2.9 log CFU/g까지만 증가한 것으로 나타나 키 토산 무첨가군(방법 1과2)과 0.5% 첨가군(방법 3)(4.2~4.5 log CFU/g)에 비하여 훨씬 효과적이었다. 본 결과에 따라, 생 꽃게를 5% acetic acid로 세척한 후 간장게장에 1% 키토산을 첨가하여 냉장온도에서 저장한다면 간장게장 제품의 미생물학적 품질 향상에 큰 도움이 될 것으로 여겨진다.
Drosophila melanogaster is mainly found in fermented and rotten fruits and is tolerant to chemicals emitted during the fermentation process. Its distinctive habitat suggests an evolutionary adaptation to environmental chemicals. In order to understand the physiological adaptation of D. melanogaster to the chemicals, we treated LC20 concentration of three chemicals (acetic acid, ethanol and 2-phenylethanol) and differential expression of the female whole body transcripts were compared with control fly (no chemical treatment). Compared to control fly, 94, 137 and 59 genes were up-regulated, while 85, 184 and 166 genes were down-regulated in acetic acid, 2-phenylethanol and ethanol treated flies, respectively. According to the KEGG enrichment analysis, genes categorized in metabolic pathway, Toll/IMD signaling pathway, lysosome and autophagy were ranked in the top groups of most changed gene sets after three chemical treatment. In addition, we selected 7 genes showing different expression levels in transcriptome analysis, and investigated their expression changes in the flies exposed to various concentration of three chemicals using quantitative PCR.
The fruit fly, Drosophila melanogaster, is a good model organism in various areas of biological science. Since D. melanogaster has been thought to be adapted to the chemical stress environment caused by the overripen, decay and fermented fruits, identification of the genes involved in chemical tolerance and investigation of their expression patterns are essential for better understanding of the physiological evolution in D. melanogaster. For investigation of the gene expression level, quantitative real-time PCR (qRT-PCR) can be applied to quantify gene expression level and selection of reliable reference gene(s) for normalization is an accurate step. In the present study, therefore, we validated the expression stabilities of ten candidate reference genes using three softwares (geNorm, NormFinder and BestKeeper) in D. melanogaster exposed to different concentrations of acetic acid, ethanol and 2-phenylethanol. Although three programs resulted in slightly different gene stability ranks, but overall tbp encoding TATA box binding protein was most stable gene in acetic acid and ethanol exposed fly, while nd encoding NADH dehydrogenase was the most suitable reference gene in the case of 2-phenylethanol treatment. In the comparison of three chemical treatment condition, nd was also suggested to be most optimal reference gene. In addition, optimal number of reference gene for accurate normalization was calculated by geNorm pairwise analysis, and selection of multiple reference genes was suggested to be better for target gene normalization method than use of a single reference gene.
ZSM-5 zeolite membranes can be tuned for hydrophilicity with varied Si/Al ratio allowing dehydration of various organic-water mixtures. α-Al2O3 supports were dip coated by silicalite-1 seed particles, dried (180°C for 12h) and calcined (450°C for 5h) for the secondary growth process. Hydrothermal synthesis of ZSM-5 zeolite membranes was carried out at 180 °C for 48 h. SEM and XRD results indicate excellent crystal morphology with high purity and preferred orientation. Prepared membranes showed a maximum perm-selectivity of 24 at 30°C for H2/SF6 separation. At that condition, H2 and SF6 permeance was 212 and 9 GPU, respectively. It was found that the permeance was higher at low Si/Al ratios, so it is expected that prepared membrane can be applicable for acetic acid dehydration.
The hollow fiber composite membrane used in pervaporation test was prepared by dip coating method on the Polyether Sulfone hollow fiber using tartaric acid added PVA solution. And each membrane solution contains H2SO4 as acid catalyst for esterification reaction between PVA and TA. Also, to increase coating uniformity, specific amount of SDS(sodium dodecyl sulfate) was contained. Prepared membrane was characterized by IR spectroscopy, swelling to observe cross-linking degree of PVA and Tartaric acid then, finally used in pervaporation test. The pervaporation test was mainly studied about effect of catalyst amount in the membrane solution and the test was performed until pervaporation value converged.
Polygonum multiflorum (Polygonaceae family) is effective to cholesterol lowering effect, increased immunity effect and whitening effect. P. multiflorum root is used for medicinal herb that can be used as raw material for food. In this study, acetic acid fermentation was adding extracts of P. multiflorum root (0%, 1%, 3%, 5%) for the developing healthy beverage. In this study, we investigated the contents of free sugars, organic acids and inorganic components of P. multiflorum root. As a result of free sugars from P. multiflorum root analysis, three kind of free sugars were determined the glucose, sucrose and lactose by HPLC. Four kind of organic acids were found in lactic acid fermented P. multiflorum root. And oxalic acid, lactic acid and succinic acid were detected in organic acids. The content of lactose and lactic acid in lactic acid fermented P. multiflorum root was the highest among the free sugars and organic acids. The content of minerals were in high orders of sodium > calcium > magnesium in P. multiflorum by acetic acid fermentation. The content of inorganic components was highest in lactic acid fermented solution with 5% and proportional to the content of P. multiflorum
Polygonum multiflorum (Polygonaceae family) is effective to cholesterol lowering effect, increased immunity effect and whitening effect. P. multiflorum root is used for medicinal herb that can be used as raw material for food. In this study, acetic acid fermentation was adding extracts of P. multiflorum root(0%, 1%, 3%, 5%) for the developing healthy beverage. In this study, we investigated the contents of free sugars, organic acids and inorganic components of P. multiflorum root. As a result of free sugars from P. multiflorum root analysis, three kind of free sugars were determined the glucose, sucrose and lactose by HPLC. Four kind of organic acids were found in lactic acid fermented P. multiflorum root. And oxalic acid, lactic acid and succinic acid were detected in organic acids. The content of lactose and lactic acid in lactic acid fermented P. multiflorum root was the highest among the free sugars and organic acids. The content of minerals were in high orders of sodium> calcium> magnesium in P. multiflorum by acetic acid fermentation. The content of inorganic components was highest in lactic acid fermented solution with 5% and proportional to the content of P. multiflorum
Acetylcholinesterase (AChE) is an enzyme for hydrolyzing neurotransmitter acetylcholine. Soluble form of AChE is generated via alternative splicing and functions as a bioscavenger in Dropsophila melanogaster. In this study, effects of ethanol and acetic acid on the soluble AChE expression were investigated. Treatment of ethanol and acetic acid results in over-expression of soluble AChE in the abdomen in a dose-dependent manner. However, no apparent change in AChE expression was observed in the head. Our finding suggests that the soluble AChE is involved in chemical defense against high concentration of ethanol, which is a common by-product from fermented food,and acetic acid, the main metabolite of ethanol. Thus, high level of ethanol and acetic acid resistance in D. melanogaster appears to be evolved via the induction mechanism of soluble AChE expression.
Acetylcholinesterase (AChE) is a hydrolase that hydrolyzes the neurotransmitter acetylcholine. Soluble form of AChE is generated via alternative splicing and functions as a bioscavenger in Dropsophila melanogaster. In this study, effects of acetic acid on the soluble AChE expression were investigated. Treatment of acetic acid resulted in over-expression of soluble AChE in the abdomen in a dose-dependent manner. The soluble AChE was determined to be expressed in the fat body. However, no apparent change in AChE expression was observed in the head. Our finding suggests that the soluble AChE is involved in chemical defense against high concentration of acetic acid, which is a common by-product in fermenting foods. The high level of acetic acid resistance in D. melanogaster, thus, appears to have been evolved via the induction mechanism of soluble AChE expression.
토마토의 착과와 수확량은 여름철 비닐하우스내 고온스트레스로 인하여 감소하게 된다. 본 연구는 여름철 화천지역에 위치한 비닐하우스에서 지베렐린(GA3)과 2,4-Dichlorophenoxy Acetic Acid(2,4-D) 처리가 토마토의 수확량, 착과율, 착과 후 과실품질에 미치는 영향을 알아보기 위해 ‘Adoration‘ 품종을 이용하여 실험하였다. GA3 0-, 5-, 10-, 15mg·L−1와 2,4-D 0-, 5-, 10mg·L−1를 개화 초기에 처리한 후 착과율, 수확량, 과실품질과 관련된 형질을 관찰한 결과, GA3 10mg·L−1처리구에서 대조구에 비해 14.2%의 착과율 증가를 보였다. GA3처리구에서는 수확량, 과중, 상품과실 수에 유의한 차이가 있었다. 2,4-D를 개화기에 처리했을 경우 착과율, 수확량, 상품과의 과중에 영향을 미쳤으며 GA3과 2,4-D를 각각 5mg·L−1 농도로 혼합처리 하였을 때 가장 높은(62.5%) 착과율을 나타내었다. 과실크기와 고형물함량은 GA3처리구에서만 유의성 있는 차이를 보였다. 따라서 여름철 비닐하우스의 고온조건에서 GA3 0mg·L−1처리구와 2,4-D 5mg·L−1를 처리했을 때 착과율이 가장 높아 많은 수확량을 기대할 수 있을 것으로 판단된다.
고농도의 초산수용액을 분리⋅농축하기 위해 polyacrylonitrile (PAN) 중공사 복합막을 제조한 후 투과증발 분리실험을 통해 제조된 복합막의 분리성능을 확인하였다. 제조된 중공사 복합막의 코팅여부를 알아보고자 SEM 사진을 측정하였으며 코팅두께가 3.85 µm로 균일하게 코팅된 것을 확인할 수 있었다. 또한 막의 투과성능평가 실험을 수행한 결과 가교제의 농도와 가교온도가 증가함에 따라 투과도는 감소하고 선택도는 증가하는 경향을 나타내었고, 대표적인 결과로 가교제인 glutaraldehyde 농도 13 wt%, 가교온도 140°C에서 투과도 250 g/m2⋅hr, 선택도 13의 결과를 얻을 수 있었으며, 또 다른 가교제로서 poly (acrylic acid) 농도 9 wt%, 가교온도 140°C일 때 투과도 330 g/m2⋅hr, 선택도 9의 값을 얻을 수 있었다.
본 연구에서는 H1-길항체로 알려진 항히스타민제의 일종인 염산 아젤라스틴을 합성하기 위하여 phthalic anhydride, 4-chlorophenylacetic acid, hydrazine 2HCl를 이용하여 4단계 반응을 거쳐 합성하였다. 첫 번째 반응은 카르복실기와 히드록실기가 제거되는 반응이고, 두 번째 반응은 3-(4-chlorobenzylidene)phthalide의 비누화 반응이다. 세 번째 반응은 일차아민의 친핵성 첨가반응이 일어나는 반응이며, 네 번째 반응은 N-methyl-1-aza-bicyclo[3,2,0]heptane에 세 번째 반응의 생성물을 첨가하여 반응시키면 4-(4-chlorobenzyl)-1-(2H)phthalazinone가 합성되는 반응이다. 합성한 생성물을 FT-IR, 1H-NMR을 이용하여 분석하였고, 80%의 수율로 합성물을 얻었다.