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White tea is a famous Chinese tea that is cooked at boiling point before drinking. The simultaneous distillation‐extraction (SDE) was used to collect volatile compounds during tea cooking. The SDE extract was dominated with green, floral, roasted and woody notes, and weak sweet note. There were 32 volatile compounds identified via gas chromatography–mass spectrometry analysis, and 19 of them had strong fragrance based on the gas chromatography‐olfactometry analyzed results. Hexanal, 2‐hexenal, cis‐3‐hexen‐1‐ol, and camphene were the main contributors to the green note. The floral note was mainly contributed by 2‐hexanone, benzeneacetaldehyde, trans‐linalool oxide, and linalool, and the sweet note was induced by trans‐β‐damascenone. The roasted note was mainly contributed by 2‐pentyl‐furan. The woody note was mainly contributed by trans‐α‐ionone and trans‐β‐ionone. Four putative reaction pathways, including amino acid degradation, carotene degradation, Maillard reaction, and glycosides hydrolysis, were figured out to explain the generation of aromatic‐active volatiles at high temperatures. This study added our knowledge on tea aroma under cooking as well as other thermal treatments. Total 32 volatile compounds were identified via gas chromatography–mass spectrometry analysis. Among them, 19 volatile substances had significant fragrance based on gas chromatography‐olfactometry analysis. Hexanal, 2‐hexenal, cis‐3‐hexen‐1‐ol, and camphene contributed green note. 2‐Hexaone, benzeneacetaldehyde, trans‐linalool oxide, and linalool contributed floral note. trans‐β‐Damascenone contributed sweet note. 2‐Pentyl‐furan contributed roasted note. trans‐α‐Ionone and trans‐β‐ionone contributed woody note. Amino acid degradation, carotene degradation, Maillard reaction, and glycosides hydrolysis were figured out to explain the generation of aromatic‐active volatiles at high temperatures.

Ginkgo biloba leaves have various health benefits due to the presence of bioactive compounds such as polyprenyl acetates, flavonoids, and terpene trilactones. However, there is little literature reported on the aromatic acids in Ginkgo biloba leaves. In this work, five aromatic acids including shikimic acid (SA), 6-hydroxykynurenic acid (6-HKA), protocatechuic acid (PA), gallic acid (GAA), and p-hydroxybenzoic acid (PHBA) were simultaneously extracted from Ginkgo biloba leaves by employing the green deep eutectic solvents (DESs). A DES tailor-made from xylitol, glycolic acid and 1,5-pentanedioic acid at a molar ratio of 1:3:1 with 50% (w/w) water addition, named as NGG50, gave higher extraction yields for the five aromatic acids. Main factors affecting the extraction process were further optimized. The highest extraction yields of SA, GAA, 6-HKA, PA, and PHBA were 94.15 ± 0.96 mg/g, 332.69 ± 5.19 μg/g, 25.90 ± 0.61 μg/g, 429.89 ± 11.47 μg/g and 67.94 ± 0.37 μg/g, respectively. The NGG50-based extraction process developed here was a successful attempt of simultaneously extracting five aromatic acids from Ginkgo biloba leaves for the first time, which could provide a new exploitation direction of Ginkgo biloba leaves.

Brown seaweed is a promising source of polysaccharides and phenolics with industrial utility. This work reports the development of a green enzyme-assisted extraction method for simultaneously extracting polysaccharides and phenolics from the brown seaweed Padina gymnospora. Different enzymes (Cellulast, Pectinex, and Alcalase), individually and in combination, were investigated, with Alcalase alone showing the highest efficiency for the simultaneous extraction of polysaccharides and phenolics. Yields from Alcalase-assisted aqueous extraction were higher than those obtained using either water alone or conventional ethanol extraction. Alcalase-assisted extraction was subsequently optimized using a response surface methodology to maximize compound recovery. Maximal polysaccharide and phenolic recovery was obtained under the following extraction conditions: a water-to-sample ratio of 61.31 mL/g, enzyme loading of 0.32%, temperature of 60.5 °C, and extraction time of 1.95 h. The extract was then fractionated to obtain alginate-, fucoidan-, and phenolic-rich fractions. Fractions exhibited potent 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity with IC50 values of 140.55 µg/mL, 126.21 µg/mL, and 48.17 µg/mL, respectively, which were higher than those obtained from conventional extraction methods. The current work shows that bioactive polysaccharides and phenolics can be obtained together in high yield through a single aqueous-only green and efficient Alcalase-assisted extraction.

Oil and protein from silkworm (Bombyx mori var. Leung Pairoj) pupae, by-product from sericulture, were extracted and evaluated for their potential uses as skin biomoisturizer. The silkworm pupae (SWP) oil and protein were simultaneously extracted by using three-phase partitioning (TPP) method and determined for their physicochemical properties including fatty acid and amino acid content, respectively. The highest yields of oil and protein at 8.24 ± 0.21% and 8.41 ± 0.26% w/w, respectively were obtained from 18 h extraction. Fatty acid analysis of SWP oil was rich in linolenic acid (37.81 ± 0.34%), oleic acid (28.97 ± 0.13%), palmitic acid (21.27 ± 0.05%), stearic acid (6.60 ± 0.09%) and linoleic acid (4.73 ± 0.21%). The clear yellow SWP oil possessed saponification value of 191.51 mg/g, iodine value of 119.37 g I2/g and peroxide value of 2.00 mg equivalent O2/kg. The SWP protein composed of 17 amino acids which aspartic acid, glutamic acid, glycine and serine were the major residues. SDS-PAGE analysis revealed that the SWP protein consisted of distinct protein at around 51, 70, 175 and over 175 kDa. Cytotoxicity of the SWP oil and protein was evaluated by using MTT assay and they showed low cytotoxicity toward keratinocyte cell (HaCat cell line). The SWP oil provided moisturizing effect on pig skin comparable to olive oil, while 1% and 2% of SWP protein showed higher moisturizing efficacy than 3% hydrolyzed collagen. The study indicated that the SWP oil and protein could be potential biomoisturizers for cosmetic products.

Microwave-assisted extraction was applied to extract rutin; quercetin; genistein; kaempferol; and isorhamnetin from Flos Sophorae Immaturus. Six independent variables; namely; solvent type; particle size; extraction frequency; liquid-to-solid ratio; microwave power; and extraction time were examined. Response surface methodology using a central composite design was employed to optimize experimental conditions (liquid-to-solid ratio; microwave power; and extraction time) based on the results of single factor tests to extract the five major components in Flos Sophorae Immaturus. Experimental data were fitted to a second-order polynomial equation using multiple regression analysis. Data were also analyzed using appropriate statistical methods. Optimal extraction conditions were as follows: extraction solvent; 100% methanol; particle size; 100 mesh; extraction frequency; 1; liquid-to-solid ratio; 50:1; microwave power; 287 W; and extraction time; 80 s. A rapid and sensitive ultra-high performance liquid chromatography method coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (EIS-Q-TOF MS/MS) was developed and validated for the simultaneous determination of rutin; quercetin; genistein; kaempferol; and isorhamnetin in Flos Sophorae Immaturus. Chromatographic separation was accomplished on a Kinetex C18 column (100 mm × 2.1 mm; 2.6 μm) at 40 °C within 5 min. The mobile phase consisted of 0.1% aqueous formic acid and acetonitrile (71:29; v/v). Isocratic elution was carried out at a flow rate of 0.35 mL/min. The constituents of Flos Sophorae Immaturus were simultaneously identified by EIS-Q-TOF MS/MS in multiple reaction monitoring mode. During quantitative analysis; all of the calibration curves showed good linear relationships (R2 > 0.999) within the tested ranges; and mean recoveries ranged from 96.0216% to 101.0601%. The precision determined through intra- and inter-day studies showed an RSD% of <2.833%. These results demonstrate that the developed method is accurate and effective and could be readily utilized for the comprehensive quality control of Flos Sophorae Immaturus.

The extraction of nucleic acid is recognized as one of the most essential steps in molecular biology for initiating other downstream applications such as sequencing, amplification, hybridization, and cloning. Many commercial kits and methods are currently available that allow the extraction of only one type of nucleic acids-DNA or RNA. However, in parallel clinical detection of several diseases, a method for simultaneous extraction of both DNA and RNA from the same source is needed in such cases. In this study, a method for simultaneous extraction of DNA and RNA from bacteria based on magnetic nanoparticles （MNPs） was described. Lysis buffers were prepared to help the nucleic acid released and adsorbed to MNPs. Then, two washing buffers were used to remove the contamination of proteins and carbohydrates. The nucleic acids were finally eluted by Deoxyribonuclease （DNase） and Ribonucleases （RNase） free water. Different factors which might affect the purification of the nucleic acid were investigated, and the quantity and quality parameters of the nucleic acid were also recorded. The DNA and RNA extracted from bacteria were then respectively subjected to polymerase chain reaction （PCR） and reverse transcription PCR （RT-PCR） to further confirm its quality. The results indicated that our method can be successfully used to simultaneously extract DNA and RNA from bacteria.

One of the considerable and disputable areas in analytical chemistry is a single-step simultaneous extraction of acidic and basic pollutants. In this research, a simple and fast coextraction of acidic and basic pollutants (with different polarities) with the aid of magnetic dispersive micro-solid phase extraction based on mixed hemimicelles assembly was introduced for the first time. Cetyltrimethylammonium bromide (CTAB)-coated Fe₃O₄ nanoparticles as an efficient sorbent was successfully applied to adsorb 4-nitrophenol and 4-chlorophenol as two acidic and chlorinated aromatic amines as basic model compounds. Using a central composite design methodology combined with desirability function approach, the optimal experimental conditions were evaluated. The opted conditions were pH = 10; concentration of CTAB = 0.86 mmol L⁻¹; sorbent amount = 55.5 mg; sorption time = 11.0 min; no salt addition to the sample, type, and volume of the eluent = 120 μL methanol containing 5 % acetic acid and 0.01 mol L⁻¹ HCl; and elution time = 1.0 min. Under the optimum conditions, detection limits and linear dynamic ranges were achieved in the range of 0.05–0.1 and 0.25–500 μg L⁻¹, respectively. The percent of extraction recoveries and relative standard deviations (n = 5) were in the range of 71.4–98.0 and 4.5–6.5, respectively. The performance of the optimized method was certified by coextraction of other acidic and basic compounds. Ultimately, the applicability of the method was successfully confirmed by the extraction and determination of the target analytes in various water samples, and satisfactory results were obtained.

The test samples are polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs), highly toxic and widely prevalent organic pollutants in natural waters. The feasibility of using dispersive liquid–liquid microextraction (DLLME) for extracting PCBs and PAHs, followed by their determination by GC–MS, was assessed in the presence of both contaminants. A DLLME method employing a binary dispersing agent was proposed, ensuring the simultaneous extraction of analytes with efficiency ranging from 80 to 97%. The proposed procedure enabled the GC–MS determination of 16 PAHs and 7 PCBs in natural waters in a wide concentration range of 2.0 × 10 –5 –0.04 µg/mL with an average error of 7–18% for PAHs and 11–18% for PCBs. The relative standard deviations for repeatability and reproducibility were found to be 3.1–6.5 and 4.3–7.7%, respectively, for PAHs, and 2.8–5.3 and 3.4–6.0%, respectively, for PCBs.

The frequency of vibration signals generated by piston pumps under the operating environment of variable speed shows non-stationary and nonlinear characteristics, leading to poor focusing of spectral energy in traditional time–frequency analysis, and the interference of variable speed increases the difficulty of the signal noise reduction and feature extraction process, which in turn enhances the diagnostic complexity of vibration signal processing and health diagnosis. In order to address this problem, this paper proposes a research method based on synchro-extracting transform (SET) and snake optimization (SO) extreme learning machines (ELM) to identify the health status of variable-speed piston pumps. Firstly, the effectiveness of the SET method in processing nonlinear signals and anti-noise is verified by single-signal and multi-signal simulation; then, a test platform for plunger pump health diagnosis is built, and the raw data with different wear levels of the distributor disk are collected, and the data are processed using SET and angular-domain sampling techniques to eliminate the influence of speed changes; and eight angular-domain and order-domain features with significant differentiation are extracted as input features; finally, a method is proposed to identify the health state of variable-speed plunger pumps. as input features; and finally, an SO algorithm is proposed to optimize ELM for health diagnosis, which solves the random assignment problem of ELM by optimizing the initial weights and bias parameters of ELM through the SO algorithm and significantly improves the classification accuracy and computational efficiency and also compares with PSO-ELM and ELM. The results show that SO-ELM can effectively solve the random assignment problem of initial weights and thresholds that exists in ELM and accurately extract fault information; SO-ELM model is better than PSO-ELM and ELM in terms of comprehensive performance such as precision rate, recall rate, and F1-score, and the average diagnostic correctness of SO-ELM model is 96.1%, which is higher than the average diagnostic correctness. The average correct diagnosis rate of SO-ELM model is 96.1%, which is 4.0% and 2.6% higher than that of ELM (92.1%) and PSO-ELM (93.5%), respectively, which can effectively diagnose the health state of the variable-speed axial piston pump, and verifies the effectiveness of the method.

Wuliangye baijiu is one of the most famous baijiu in China, with a rich, harmonic aroma profile highly appreciated by consumers. Thousands of volatiles have been identified for the unique aroma profile. Among them, fatty acid esters have been identified as the main contributors to the aroma profile. In addition, many non-ester minor compounds, many of which are more polar than the esters, have been identified to contribute to the characteristic aroma unique to Wuliangye baijiu. The analysis of these minor compounds has been challenging due to the dominance of esters in the sample. Thus, it is desirable to fractionate the aroma extract into subgroups based on functional group or polarity to simplify the analysis. This study attempts a new approach to achieve simultaneous volatile extraction and fractionation using tandem LiChrolut EN and silica gel solid-phase extraction (SPE) columns. A baijiu sample (10 mL, diluted in 40 mL of water) was first passed through the LiChrolut EN (1.0 g) column. The loaded LiChrolut EN column was then dried with air and coupled with a silica gel (5.0 g) SPE column with anhydrous Na2SO4 (10.0 g) in between. The volatile compounds were eluted from the LiChrolut EN column and simultaneously fractionated on the silica gel column based on polarity. The simultaneous extraction and fractionation technique enabled the fractionations of all fatty acid esters into less polar fractions. Fatty acids, alcohols, pyrazines, furans, phenols, hydroxy esters, and other polar compounds were collected in more polar fractions. This technique was used to study the volatile compounds in Wuliangye, Moutai, and Fengjiu baijiu. In addition to fatty acid esters, many minor polar compounds, including 2,6-dimethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-3,5-dimethylpyrazine, p-cresol, and 2-acetylpyrrole, were unequivocally identified in the samples. The procedure is fast and straightforward, with low solvent consumption.