• Membrane and Water Treatment
• /
• 제6권4호
• /
• pp.309-321
• /
• 2015

We report in this study the synthesis of mixed matrix reverse osmosis membranes by interfacial polymerization (IP) of thin film nanocomposite (TFNC) on porous polysulfone supports (PS). This paper investigates the synthesis of ZnO nanoparticles (NPs) using the sol-gel processing technique and evaluates the performance of mixed matrix membranes reached by these aerogel NPs. Aqueous m-phenyl diamine (MPD) and organic trimesoyl chloride (TMC)-NPs mixture solutions were used in the IP process. The reaction of MPD and TMC at the interface of PS substrates resulted in the formation of the thin film composite (TFC). NPs of ZnO with a size of about 25 nm were used for the fabrication of the TFNC membranes. These membranes were characterized and evaluated in comparison with neat TFC ones. Their performances were evaluated based on the water permeability and salt rejection. Experimental results indicated that the NPs improved membrane performance under optimal concentration of NPs. By changing the content of the filler, better hydrophilicity was obtained; the contact angle was decreased from $74^{\circ}$ to $32^{\circ}$. Also, the permeate water flux was increased from 26 to 49 L/m2.h when the content of NPs is 0.1 (wt.%) with the maintaining of lower salt passage of 1%.

• Natural Product Sciences
• /
• 제29권2호
• /
• pp.83-90
• /
• 2023

To our knowledge, this is the first study aiming to optimize the extraction conditions of total phenolic compounds (TPC) and total flavonoids contents (TFC) from Argania spinosa leaves using Response Surface Methodology (RSM) with a Box-Behnken design (BBD). The optimal conditions obtained were 5% (w/v) solvent-to-solid ratio, 72.33% ethanol concentration, and 10h ours as an extraction time, which resulted in an extract with maximum TPC (131.63 mg GAE/g dw) and TFC (10.66 mg QE/g dw). Under the optimal extraction conditions, the antioxidant activity of the extracts of leaves of argan tree showed a moderate antiradical capacity of DPPH (IC₅₀ = 0,130 mg/mL) and ABTS (IC₅₀ = 0.198 mg/mL). However, the leaves of argan tree showed a very interesting reducing power of Iron (IC₅₀ = 0.448 mg/ml) which is similar to that of the ascorbic acid (IC₅₀ = 0.371 mg/mL).

• 한국축산식품학회지
• /
• 제44권5호
• /
• pp.1126-1141
• /
• 2024

Antioxidant activity of freeze-dried paprika powder and storage properties of emulsion-type pork sausages containing diverse concentrations of this powder (0%, 1%, 2%, and 3%) were analyzed. Antioxidant activities of red and yellow paprika powders were analyzed by evaluating their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), total phenol content (TPC), and total flavonoid content (TFC). The yellow paprika powder exhibited remarkably higher DPPH radical scavenging activity, FRAP values, and TPC than the red paprika powder (p<0.05), while TFC showed no remarkable difference between them (p>0.05). Storage properties of sausages containing the yellow paprika powder were analyzed by evaluating their water holding capacity, cooking yield, and thiobarbituric acid reactive substance (TBARS), and volatile basic nitrogen (VBN) values. The 3% yellow paprika powder group showed remarkably higher water-holding capacity and cooking yield compared to the 0% group (p<0.05). TBARS values were remarkably lower in the 2% and 3% yellow paprika powder groups than in the 0% group at all weeks (p<0.05). VBN value was remarkably lower in the 3% yellow paprika powder group than in the 0% group at all weeks (p<0.05). Overall, addition of 3% yellow paprika powder improved the storage properties of emulsion-type sausages.

• Journal of the Korean Wood Science and Technology
• /
• 제46권1호
• /
• pp.38-47
• /
• 2018

본 연구에서는 해당화 부위별 열수추출물에 대한 항산화 활성을 분석하였다. 해당화의 부위별 추출물의 총 페놀성 화합물과 총 플라보노이드 함량은 잎에서 가장 높았으며, 각각 107.29, 24.28 mg/g로 나타났다. DPPH와 ABTS 라디칼 소거능은 꽃, 잎, 씨, 열매, 과육 추출물 순으로 활성이 높았으며, 꽃 추출물의 DPPH, ABTS 라디칼 소거능은 각각 $IC_{50}=0.87$, $0.27mg/m{\ell}$로 나타났다. 항산화 활성이 가장 높았던 꽃과 잎 추출물에서는 gallic acid가 각각 4.51, 0.97 mg/g로 다른 부위별 열수추출물에서보다 높았다. 해당화 부위별 열수추출물을 분획한 결과(A-F), 꽃 추출물의 C 분획물에서 높은 항산화 활성을 확인하였다. 이것은 총 페놀성 화합물과 총 플라보노이드 함량(3305.43, 878.42 mg/g)에 의한 것이며, p-value < 0.001에서 총 페놀성 화합물과 총 플라보노이드의 함량이 증가할수록 라디칼 소거능이 증가하는 상관관계 결과와 일치하였다. 따라서 해당화 열수추출물은 식품, 화장품, 의약품 산업 등에서 천연 항산화제로 사용가능할 것이다.

• Journal of Korean Neurosurgical Society
• /
• 제46권4호
• /
• pp.322-327
• /
• 2009

Objective : Posterior lumbar interbody fusion (PLIF) is considered to have the best theoretical potential in promoting bony fusion of unstable vertebral segments by way of a load sharing effect of the anterior column. This study was undertaken to investigate the efficacy of PLIF with cages in chronic degenerative disc disease with Modic degeneration (changes of vertebral end plate). Methods : A total of 597 patients underwent a PLIF with threaded fusion cages (TFC) from 1993 to 2000. Three-hundred-fifty-one patients, who could be followed for more than 3 years, were enrolled in this study. Patients were grouped into 4 categories according to Modic classification (no degeneration : 259, type 1 : 26, type 2 : 55, type 3 : 11). Clinical and radiographic data were evaluated retrospectively. Results : The clinical success rate according to the Prolo's functional and economic outcome scale was 86% in patients without degeneration and 83% in patients with Modic degeneration. The clinical outcomes in each group were 88% in type 1, 84% in type 2, and 73% in type 3. The bony fusion rate was 97% in patients without degeneration and 83% in patients with Modic degeneration. The bony fusion rate in each group was 81% in type 1, 84% in type 2, and 55% in type 3. The clinical success and fusion rates were significantly lower in patients with type 3 degeneration. Conclusion : The PLIF with TFC has been found to be an effective procedure for lumbar spine fusion. But, the clinical outcome and bony fusion rates were significantly low in the patients with Modic type 3. The authors suggest that PLIF combined with pedicle screw fixation would be the better for them.

• 한국균학회지
• /
• 제46권1호
• /
• pp.51-57
• /
• 2018

본 연구에서는 표고버섯 원목재배 방법을 통하여 생산한 버섯의 품종별 항산화 특성을 분석하였다. 원목재배 표고버섯 추출물의 총 폴리페놀과 총 플라보노이드 함량을 측정한 결과는 5.10~10.88 mg GAE/g과 0.76~5.78 mg QE/g으로 나타났으며, 원목재배용 표고버섯 품종 중에서 천백고가 다른 품종들에 비해서 가장 높게 나타났다(총 폴리페놀 10.88 mg GAE/g, 총 플라보노이드 5.78 mg QE/g). 원목재배 표고버섯 추출물의 DPPH 라디칼 소거 활성과 FRAP을 측정한 결과 추출물의 농도에 비례하여 전자공여능과 환원력이 증가하였으며, 원목 재배용 표고버섯 중에서 천백고는 0.2~2.0 mg/mL 농도 범위에서 38.19~90.11%과 0.075~0.231로 다른 품종들에 비해서 가장 높게 나타났다. 본 연구를 통해 원목재배용 표고버섯 품종에 따른 항산화 활성을 확인하였으며, 향후 원목재배용 표고버섯 품종 개발과 항산화 활성 연구에 있어 기초 자료로서 활용될 수 있을 것이다.

• 멤브레인
• /
• 제34권4호
• /
• pp.205-215
• /
• 2024

본 연구는 폴리케톤(PK) 지지체를 이용한 유기용매 역삼투(OSRO) 분리막 제조를 목적으로 하였다. 비용매 유도상분리 방법(NIPS)을 통해 PK 지지체를 제작하였고, PK 지지체 위에 polyamide layer를 계면 중합하여 thin-film composite(TFC) 형태로 OSRO 분리막을 완성하였다. 이후 OSRO 분리막의 표면과 단면 구조 및 표면의 화학적 구조를 분석하였고 수투과도와 염 제거율은 각각 약 1.28 LMH/bar와 99.0%의 결과를 얻었다. 또한 OSRO 분리막의 polyamide layer는 유기용매침지 1일 동안 매우 안정적이었고, 단일 유기용매 투과도 경향성은 유기용매 나노여과(OSN) 분리막의 투과도 모델과 일치하였다. OSRO 분리막의 MWCO는 MeOH 상에서 240 g/mol이었다. OSRO 분리막의 MeOH-toluene 혼합용액에 대한 투과도와 separation factor는 상용 OSN 분리막보다 각각 200%와 60%의 높은 결과를 얻었다.

• 한국환경과학회:학술대회논문집
• /
• 한국환경과학회 2008년도 추계학술발표회 발표논문집
• /
• pp.193-197
• /
• 2008

까마중과 어성초의 에탄올 추출물의 기능적 특성을 검토하고, 환원력을 기준한 항산화 활성과 아질산염 소거능을 측정하였다. 추출액의 가용성 고형분은 까마중 잎>어성초>까마중뿌리>까마중 열매의 순이었으나 TFC함량은 어성초가 가장 높고 까마중의 경우 잎>열매>뿌리의 순이었다. 한편 항산화활성은 까마중 잎>어성초>까마중 열매>까마중 뿌리의 순이었다. 아질산염 소거능은 실험 pH범위에서 까마중 잎이 어성초 보다 높았으며, 모든 추출액에 대하여 낮은 pH에서의 NSA가 더 높은 값을 보였다.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2011년도 추계학술대회 논문집
• /
• pp.394-395
• /
• 2011

• 한국막학회:학술대회논문집
• /
• 한국막학회 2004년도 춘계 총회 및 학술발표회
• /
• pp.82-85
• /
• 2004

Flux-enhancement mechanism of thin-film-composite (TFC) membranes for the reverse comosis (RO) process was newly explained by positron annihilation lifetime spectroscopy (PALS) that has been found to be applied for detecting molecular vacancies or pores having sizes that are equivalent to salt or hydrate ions in RO membrane.(omitted)