This study explored how enzyme type (cellulase and pectinase), concentration, and mixing ratio influence the functional compounds and antioxidant activities of purple sweet potato (Ipomoea batatas L.). The enzyme treatment significantly impacted all measured parameters. At a cellulase concentration of 30 units, the total anthocyanin content reached 399.4 mg/100g dry weight (DW), representing a 163% increase compared to the control (151.6 mg/100g DW). Total polyphenol (1,799.7 mg GAE/100g DW) and flavonoid (475.3 mg CE/100g DW) contents also peaked under these conditions, while higher enzyme concentrations or increased pectinase ratios reduced extraction efficiency. The highest ABTS radical scavenging activity was noted at 30 units of cellulase (954.0 mg TE/100g DW) and at 80 units in a combined treatment of cellulase (2) to pectinase (1) (927.2 mg TE/100g DW), suggesting that moderate enzyme synergy enhances antioxidant release. Conversely, DPPH activity decreased with higher enzyme concentrations, with all combined treatments yielding lower results than the control. Overall, the optimal condition for enhancing both functional compound extraction and antioxidant activity in purple sweet potato was identified as a single treatment with cellulase at 30 units.

This study optimized the extraction of β-carotene and antioxidant compounds from orange-fleshed sweet potato (Ipomoea batatas L.) using response surface methodology (RSM) with ethyl lactate as a green solvent. A central composite design (CCD) was utilized to evaluate how the solvent-to-sample ratio, temperature, and extraction time affected efficiency. The regression model was statistically significant (Adj. R2=0.67), revealing that the solvent-to-sample ratio was the most influential factor, while temperature and time had relatively minor effects. The optimal conditions identified were a ratio of 12 mL/g, a temperature of 35°C, and an extraction time of 30 minutes, which resulted in a yield of 27 mg/100g of β-carotene, along with high levels of polyphenols, flavonoids, and strong antioxidant activities as measured by DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulfonic acid)) assays. Validation experiments demonstrated a close alignment between predicted and experimental values, confirming the model's robustness. These findings indicate that ethyl lactate effectively extracts not only carotenoids but also a wide range of antioxidants, underscoring its potential as a sustainable solvent for developing functional food ingredients.

Edible mushrooms are recognized as a rich source of diverse metabolites, including polysaccharides, amino acid derivatives, terpenoids, polyphenols, sterols, and flavonoids. These compounds have been extensively reported to have antioxidant, anti-inflammatory, immunomodulatory, anticancer, and metabolic regulatory activities, thereby underscoring their scientific and industrial significance in nutraceutical and pharmaceutical applications. However, conventional extraction methods, which are simple and cost-effective, have limitations in large-scale processes, including long processing times, excessive use of solvents, low yields, and degradation of heat-sensitive compounds, which limit scalability. Therefore, eco-friendly extraction methodologies have emerged as sustainable alternatives. Advanced extraction strategies using food-grade solvents, such as deep eutectic solvents, in conjunction with ultrasound or microwave assistance, enable selective recovery of metabolites under mild conditions, enhancing yield and minimizing the environmental impact. In this review recent progress in advanced extraction methodologies, with respect to efficiency, selectivity, and sustainability, are critically assessed. The industrial implications, including case studies of advanced extraction methodologies applied to secondary metabolites, and the potential of edible mushrooms as renewable bioresources or the development of nextgeneration functional foods and natural therapeutics, are also discussed.

리차드 오티(Richard Auty), 마이클 로스(Michael Ross) 등과 같은 학자들은 원자재 생산과 수출에 기반하고 있는 국가에서 반복해서 나타 나는 정치 경제적 불안정, 분쟁, 빈곤, 불평등, 환경 오염, 인권 침해 등 의 악순환 현상을 두고 ‘자원의 저주(resource curse)’ 혹은 ‘풍요의 역 설(paradox of plenty)’로 불렀다. 본 연구의 목적은 아프리카의 대표적 인 자원의 저주 사례라고 꼽히는 콩고민주공화국(DRC) 카탕가 지역 광 산 개발 사례를 통해, 자원의 저주가 반복적으로 나타나는 원인을 얌비 (Llambí)의 ‘지대 국가’ 개념을 통해 분석하는 것이다. 분석 결과, 역사 적으로 카탕가 지역의 광산 개발은 DRC 발전에 중추적 역할을 해왔으 며, 지대 국가는 역사적 변화에 따라 지대 추구 방식을 변화 시켜왔다. 특히 2000년대 이후 광산 부문의 구조가 대규모 산업 광산 개발과 전통 적 소규모 광산 개발로 이분화되는 과정에서 DRC에는 ‘신(新) 지대 국 가’가 등장했음을 알 수 있었다. 신 지대 국가의 지대 추구 방식은 DRC 가 엄청난 규모의 광산 투자를 통해 광산 붐을 맞이하고 있음에도 불구 하고, 여전히 산업 구조의 다각화를 이루지 못하고 빈곤율이 높으며, 광 산 추출 과정에서의 각종 사회 환경적 문제를 양산하는 ‘자원의 저주’에 서 벗어나지 못하는 주된 이유 중 하나임을 밝혔다.

Crocin is a glycosyl ester of crocetin acid and is classified as a water-soluble carotenoid. It is abundant in Gardenia jasminoides (Ellis GJE.) GJE is a natural ingredient widely used to impart an orange-yellow hue to traditional Vietnamese products such as cakes, jelly, and fish sauce. Crocin, a key bioactive compound in Gardenia, has been used in medicine for its antioxidant, anticancer, and memory-enhancing properties. In this study, we introduced an effective strategy for the extraction of crocin pigments derived from Gardenia. The pretreatment of Gardenia is crucial in the extraction process, with the most effective method involving freeze-drying Gardenia followed by grinding with liquid nitrogen to enhance the extraction efficiency. Second, this study focused on optimizing crocin extraction using ultrasound-assisted methods by evaluating key parameters, including ultrasonic amplitude, extraction time, materialto- solvent ratio, and solvent concentration. The crocin content reached 95.04±0.81 mg ․ g–1dw. Finally, the optimal ultrasound-assisted extraction conditions were determined using response surface methodology, ensuring the maximum extraction efficiency of crocin (ultrasonic amplitude (60.41%), extraction time (5.95 min), solvent concentration (41.48%), and material/solvent ratio (2.7 g/100 mL). The maximum concentration of crocin from Gardenia was determined to be 97.05±1.00 mg ․ g–1dw.

In this study, domestic soybean cultivars were extracted using water, 70% ethanol, and 100% ethanol. The contents of polyphenols, flavonoids, and antioxidant activities of these extracts were measured. For the water extracts, the polyphenol content was significantly higher in the Daewon cultivar compared to the others. Ethanol extracts contained lower levels than the water extracts, and, unlike the water extracts, there was no significant difference between the cultivars. The flavonoid content in the Jinpung cultivar was the highest among the water extracts, and this content was greater in the water extract than in the ethanol extract. In terms of ABTS radical scavenging activity, Daewon and Taekwang exhibited significantly higher activity in the water extracts. The Jinpung cultivar showed the highest activity in the 70% ethanol extract, which was slightly lower than that of the water extract. DPPH radical scavenging activity was found to be higher in Taekwang than in the other cultivars. In the 70% ethanol extract, Taekwang demonstrated high antioxidant activity, similar to that of the water extract. A correlation analysis of antioxidant components and antioxidant activity in soybean cultivars revealed the highest r value of 0.9326 between the contents of flavonoid compounds and polyphenol compounds.

Phellinus linteus, a medicinal mushroom with potent antioxidant properties, contains bioactive compounds, such as polyphenols and flavonoids. To optimize the extraction of skin-whitening compounds, ultrasound-assisted extraction combined with statistically based optimization was used to simultaneously extract total polyphenol content (TPC), radical scavenging activity (RSA), and tyrosinase activity inhibition (TAI). Extraction variables, including extraction time (X1:4.8 ~ 55.2 min), extraction temperature (X2:26.4 ~ 93.6oC), and ethanol concentration (X3:13.0 ~ 97.0%), were varied in 17 experimental cycles based on a central composite design. Quadratic regression models for TPC, RSA, and TAI had coefficients of determination (R2) greater than 0.92, demonstrating well-fitted models and statistical significance. Analysis of variance revealed that all three variables significantly influenced extraction efficiency (p < 0.0041), with ethanol concentration (X3) having the most pronounced effect. The optimal extraction conditions were 80.0 min, 82.5oC, and 64.8% ethanol, yielding predicted values of 6.42 mg GAE/g DM for TPC, 73.71% for RSA, and 85.04% for TAI. These results suggest that a moderate ethanol concentration combined with adequate thermal input maximizes the extraction of antioxidant and tyrosinase inhibitory activities specifically associated with skin-whitening effects.

Synthesis of high-purity magnesium hydroxide using dolomite and bittern is important for use in various applications. We synthesized magnesium hydroxide using bittern and dolomite, which are domestic resources. In Bittern, there is a high concentration of Mg2+ ions, but the impurity Ca2+ ion content is also significant, requiring a purification process to remove it. There are two main methods for this purification. Firstly, there is a separation method that utilizes the difference in solubility between Mg2+ ions and Ca2+ ions by using sulfuric acid on dolomite. Adding MgSO4 solution from dolomite to Bittern removes Ca2+ ions as CaSO4. This process simultaneously purifies Ca impurities and increases the Mg/Ca ratio by adding extra Mg2+ ions. In this study, purified bittern was obtained by using dolomite and sulfuric acid to extract MgSO4, which was then used to purify Ca2+ ions. High-purity Mg(OH)2 was synthesized by optimizing the NaOH and NH4OH ratio as an alkaline precipitant. Mg(OH)2 synthesis technology made by effectively removing Ca ions from dolomite and bittern can contribute to domestic pilot production.

결빙되거나 적설이 있는 도로와 같이 마찰이 작은 노면에서는 일반 노면과 비교했을 때 제동거리가 크게 증가하기 때문에 심각한 교통사고로 이어질 수 있다. 이에 블랙 아이스(Black ice)와 같은 노면 위험을 감지 하기 위한 노면 분류 기술에 대한 연구가 지금까지 지속적으로 이루어지고 있다. ESC(Electronic Stability Control) 시스템은 차량 자세 제어를 통해 마찰이 작은 노면에서 차량의 미끄러짐 및 전복을 방지하는 능동 안전시스템(Active safety system)이다. ESC 시스템의 성능을 위해서는 정확한 노면 마찰 계수(Road friction coefficient) 추정을 통한 노면 분류가 중요하다. 최근의 노면 분류 기술은 카메라, LiDAR 등의 이미 지 기반의 방법에 중점을 두고 연구가 진행되고 있다. 그러나 이러한 이미지 기반의 방법들은 정확도가 낮을 뿐만 아니라 높은 계산 복잡도의 문제를 가지고 있다. 이뿐만 아니라 높은 비용으로 인해 상용화 측면에서도 단점을 드러내고 있다. 본 연구에서는 그림1처럼 센서 융합 기술을 활용하여 이미지 기반 방법의 문제점을 해결하고자 한다. 차량 횡방향 동역학 모델(Vehicle lateral dynamic model)을 선형화하여 칼만 필터(Kalman filter)를 적용한 노면 마찰 계수 추정 알고리즘을 설계하고, 기계학습(Machine learning) 모델을 적용하여 블랙 아이스 검출 알고 리즘을 설계한다. 전기차 CAN 버스로부터 얻을 수 있는 차량 종방향 가속도(Vehicle longitudinal acceleration)를 제어 입력으로 하고, 요 레이트(Yaw rate)를 측정값으로 하여 칼만 필터에 적용하여 차량 종 방향 속도(Vehicle longitudinal velocity)와 차량 횡방향 속도(Vehicle lateral velocity), 요 레이트, 차량 횡방 향 힘(Vehicle lateral force)을 추정한다. 이때 전통적인 칼만 필터 대신 EKF-UI(Extended kalman filter with unknown input)를 적용하여 시스템 행렬의 크기를 줄여 계산 복잡도를 감소시키고 차량의 거동 변화 를 보다 정확하게 반영할 수 있도록 하였다. 추정된 차량 종방향 속도, 차량 횡방향 속도, 요 레이트를 통해 사이드 슬립 각(Side slip angle)을 구해 사이드 슬립 각과 차량 횡방향 힘의 관계를 이용해 특징들을 찾아 기계학습 모델(e.g. 앙상블 기법, SVM 등)을 적용하여 블랙 아이스를 검출할 수 있다. MATLAB/Simulink SW 및 CarSim을 사용하여 개발한 알고리즘의 성능을 검증하였으며, 본 연구의 결과는 ESC 시스템의 성능 을 개선시켜 차량의 미끄러짐으로 인한 교통사고의 예방에 도움이 될 것으로 예상한다. 여기에 스마트 타이 어(Smart tire)의 센서도 추가해 노면과 타이어 사이의 직접적인 데이터를 추가해 검출 성능을 높일 것이다.

상수도 배관에서 누수 또는 이상을 감지하는 기계학습 및 인공신경망 분류 모델에 대한 연구가 활발히 진행되어 왔다. 그러나 누수음 데이터는 시간과 환경에 따라 계속 변동하기 때문에, 입력 데이터의 변화에도 일정 수준 이상의 분류 성능을 유지하는 분류 모델을 찾는 데 어려움이 있다. 본 연구에서는 모델 선택과 초매개변수 조정보다 데이터 전처리 방법이 분류 성능 향상에 더 큰 영향을 미친다는 점에 주목했다. 변동성이 큰 누수음의 특징을 효과적으로 추출하기 위해 푸리에 변환 및 MFCC(Mel-Frequency Cepstral Coefficients)를 사용하였으며, 일부 정보가 중복될 가능성을 고려하여 다중공선성에 덜 민감한 트리 기반 모델을 사용해 누수음의 분류 성능을 평가했다. 연구 결과, 푸리에 변환과 MFCC를 결합한 데이터 세트를 사용했을 때 LightGBM 모델의 분류 정확도가 84.62%로 나타났으며, 각각의 전처리 방법을 단독으로 사용했을 때보다 더 높은 성능을 달성하였다. 이 결과는 두 전처리 방법의 상호 보완적 특성이 분류 성능 향상에 기여했음을 입증하며, 상수도 관망 누수 탐지 시스템 개발에 중요한 기여를 할 것으로 기대된다.

This paper introduces a simple and reliable photometric calibration method to extract Hα line flux from narrowband images. The equivalent width of the Hα line (EWHα) is derived using two- and simplified three-filter methods. Synthetic photometry of CALSPEC stars demonstrates the dependency of EWHα on the V − R color, described by a skewed Gaussian function within −0.1 < V − R < 0.7. Systematic errors of the two- and three-filter methods are analyzed under 0%–10% R-band flux contamination. Although the three-filter method underestimates EWHα by 10%, it exhibits less scatter compared to the two-filter method. The simplified three-filter method was validated with the Landolt SA 107 field and surpasses the two-filter method in terms of precision and accuracy. Additionally, applying our method to V960 Mon yields EWHα consistent with high-resolution spectroscopic results.

In order support the design support system of small and medium-sized shipbuilding companies that carry out designs using 2D CAD, this study developed a system that automatically calculates the cable length by extracting the Y-axis value expressed as text data in 2D CAD. By setting the equipment where the cable starts and ends, the essential route and the installation rate were checked so that the optimal route of the cable could be calculated. As a result, the value calculated based on the optimal route and length of the cable by extracting the data of 2D CAD through this study was the same as the value previously calculated by the actual user, and the installation rate was less than 130% so there was no problem with the on-site installation. In addition, it was confirmed that the cable length calculated through this was reduced by about 7% compared to the existing work.

Nanoparticles, especially those derived from plant extracts, are becoming increasingly popular as a bio-based, environmentally friendly alternative to conventional technologies. The Maui rose, a flowering plant with medicinal and therapeutic properties, is one of the most important of these materials because its extract component has antibacterial, antioxidant and anti-inflammatory biological activity. In this work, we report on synthesizing and characterizing iron oxide nanoparticles (Fe2O3) extracted from flower plants (Borago), to create persistent and environmentally friendly antibacterial agents. As part of the chemical formation process, Fe2O3 nanoparticles were extracted from specific flower plants utilizing a series of carefully regulated chemical reactions. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) of the samples were studied. The nanoparticles produced were analyzed using common microbiological methods and studies (EDS). The antibacterial activity of the Fe2O3 nanoparticles and their effect on a range of microorganisms were evaluated. The results demonstrated that Fe2O3 nanoparticles were successfully synthesized with a specific crystal structure and good anti-bacterial activities.

Sage (Salvia officinalis) contains various active compounds, including flavonoids and terpenes. In this study, the terpenes content, including camphor, borneol, and eucalyptol, was analyzed. Both subcritical water and conventional solvent extraction methods were used. Using subcritical water extraction, the optimal extraction conditions were determined based on temperature and time to selectively extract the desired components from the sage. These optimal extraction conditions were as follows: camphor (130°C for 5 min, 2.73±0.39 mg/g), borneol (130°C for 5 min, 0.72±0.07 mg/g), and eucalyptol (150°C for 5 min, 0.51±0.03 mg/g). A comparison of extracts obtained via subcritical water extraction technology and various solvents revealed that the extracts obtained using subcritical water extraction had higher levels of all three components. This indicates that subcritical water extraction is more efficient and faster than traditional solvent extraction methods. Moreover, these results suggest that subcritical water extraction technology has the potential to be applied as an eco-friendly alternative to traditional extraction methods for obtaining active compounds like terpenoids.