Kinetic and thermodynamic characteristics of ultrasound-assisted extraction for recovery of paclitaxel from biomass

Effects of slit dual-frequency ultrasound-assisted pulping on the structure, functional properties and antioxidant activity of Lycium barbarum proteins and in situ real-time monitoring process

To improve the protein dissolution rate and the quality of fresh Lycium barbarum pulp (LBP), we optimized the slit dual-frequency ultrasound-assisted pulping process, explored the dissolution kinetics of Lycium barbarum protein (LBPr), and established a near-infrared spectroscopy in situ real-time monitoring model for LBPr dissolution through spectral information analysis and chemometric methods. The results showed that under optimal conditions (dual-frequency 28-33 kHz, 300 W, 31 min, 40 °C, interval ratio 5:2 s/s), ultrasonic treatment not only significantly increased LBPr dissolution rate (increased by 71.48 %, p < 0.05), improved other nutrient contents and color, but also reduced the protein particle size, changed the amino acid composition ratio and protein structure, and increased the surface hydrophobicity, zeta potential, and free sulfhydryl content of protein, as well as the antioxidant activity of LBPr. In addition, ultrasonication significantly improved the functional properties of the protein, including thermal stability, foaming, emulsification and oil absorption capacity. Furthermore, the real-time monitoring model of the dissolution process was able to quantitatively predict the dissolution rate of LBPr with good calibration and prediction performance (Rc = 0.9835, RMSECV = 2.174, Rp = 0.9841, RMSEP = 1.206). These findings indicated that dual-frequency ultrasound has great potential to improve the quality of LBP and may provide a theoretical basis for the establishment of an intelligent control system in the industrialized production of LBP and the functional development of LBPr.

Comparative analysis of three kinds of extraction kinetic models of crude polysaccharides from Codonopsis pilosula and evaluate the characteristics of crude polysaccharides

In this study, the second-order model, Fick's second law of diffusion, and the Peleg model were used to evaluate the extraction kinetic model of polysaccharide (CPP) from Codonopsis pilosula. The characteristic functional groups, surface structure, and physical and chemical properties of CPP were analyzed by multi-spectroscopic and microscopic techniques. The results showed that the extraction process agreed well with the second-order model, Fick's second diffusion law, and Peleg model. Rheological tests showed that CPP exhibited different viscosity changes under different conditions (Solution viscosity was inversely proportional to temperature, time, etc.; proportional to polysaccharide concentration, Na+ content, etc.). CPP was composed of molecular aggregates composed of small particles, with more pore structure and basically completely decomposed at 130 °C. The hypoglycemic study showed that CPP had a strong inhibitory effect on α-glycosidase than α-amylase. The morphology and subsequent structural features, anti-diabetic potential, and rheological properties of CPP were revealed to provide a theoretical basis for the development of pharmaceutical preparations or health food and functional food for the treatment of diabetes.

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Supplementary Information

The online version contains supplementary material available at 10.1007/s13399-022-02518-w.

Preparation and application of modified three-dimensional cellulose microspheres for paclitaxel targeted separation

In this article, we successfully prepared three-dimensional cellulose microspheres modified by molecularly imprinted polymer for paclitaxel recognition and separation (3D-CM &PTX&MIPs). The material was characterized by Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), Thermogravimetric Analysis (TG) and diffraction of X-rays (XRD). Under the optimized adsorption conditions, the maximum adsorption capacity reached 65.7 mg/g. And after 5 runs of reuse, (3D-CM&PTX&MIPs) still maintained a reusability rate of 90%. Besides, (3D-CM&PTX&MIPs) showed excellent selectivity for target PTX. Finally, (3D-CM&PTX&MIPs) was used for PTX recognition and separation in the extracts of yew leaves. This research laid a good foundation and scientific basis for the efficient, environmentally friendly, and rapid enrichment of metabolites in plants using bio-based molecularly imprinted polymers.

Optimization of Taxol Extraction Process Using Response Surface Methodology and Investigation of Temporal and Spatial Distribution of Taxol in Taxus mairei

Taxus mairei is an important source for industrial extraction of taxol in China. However, the standard and steps of extraction are currently not uniform, which seriously affects the taxol yield. In the present study, the influence of four factors (methanol concentration, solid-liquid ratio, ultrasonic extraction temperature, and ultrasonic extraction time) on the taxol yield was successively explored in T. mairei. A response surface methodology (RSM) was used to optimize the extraction process based on the single-factor experiments above. The optimal conditions were as follows: methanol concentration was 90%, solid-liquid ratio was 1:15 (g/mL), ultrasonic extraction temperature was 40 °C and ultrasonic extraction time was 60 min. Moreover, the twigs and needles from T. mairei with different tree ages were treated by the optimum extraction process, which further revealed temporal and spatial distribution of taxol in the reproducible tissues. Interestingly, the taxol content was relatively higher in needles of T. ‘Jinxishan’ (a cultivar from T. mairei with yellow aril, FY), but was less in FY twigs. The accumulation of taxol in twigs and leaves of females (with red aril, FR) was significantly higher than that of males (M); however, the content showed a decreasing trend with the increasing tree ages. Therefore, it is suitable to increase the proportion of female trees especially the FY leaves as raw materials for the industrial production of taxol from T. mairei, and the tree ages should be better controlled at 3–7 years.

Energy-efficient pretreatments for the enhanced conversion of microalgal biomass to biofuels

The physiological properties, including biochemical composition and cell wall thickness, of microalgal species have a remarkable effect on the pretreatment of biomass and its further conversion to biofuels. In the present study, multiple biofuels (bioethanol, higher alcohols (C3-C5), and biodiesel) were produced using energy-efficient microwave pretreatment, successive carbohydrate/protein fermentation, and lipid transesterification from three microalgal strains (Pseudochlorella sp., Chlamydomonas mexicana, and Chlamydomonas pitschmannii). The microwave pretreatment method required the lowest specific energy (5 MJ/kg) compared to ultrasound pretreatment. The proposed integrated approach achieved high conversion efficiency (46%) and maximum biomass utilization (93%) of C. mexicana with improved yields of bioethanol (0.46 g-ethanol/g-carbohydrates), higher alcohols (0.44 g-higher alcohols/g-proteins), and biodiesel (0.74 g-biodiesel/g-lipids). This study suggests that the application of an appropriate pretreatment method for microalgal strains having different physiological properties is essential for improving the extraction efficiency and conversion of biomass to biofuels with less waste production.

Ultrasound-Assisted Extraction of Taxifolin, Diosmin, and Quercetin from Abies nephrolepis (Trautv.) Maxim: Kinetic and Thermodynamic Characteristics

Extraction behaviors of the 3 flavonoids taxifolin, diosmin, and quercetin have been investigated in Abies nephrolepis leaves and bark. The following operation parameters—ethanol volume fraction, liquid–solid ratio, temperature, ultrasound irradiation power and time, and ultrasound frequency—were varied to study their effect on the yield of the 3 flavonoids during extraction. The results showed that a low extraction efficiency occurred at 293.15 K due to slow kinetics, while the situation was significantly improved at 333.15 K. The kinetic data for the extraction yields of the 3 flavonoids achieved good fits by the first-order kinetic model. From the thermodynamic analysis results, we realized that the ultrasound-assisted extraction of taxifolin, diosmin, and quercetin from the leaves and bark of A. nephrolepis was a spontaneous and endothermic process in which the disorder increased (ΔG⁰ < 0, ΔH⁰ > 0, and ΔS⁰ > 0). According to the response surface methodology (RSM) analysis, under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 39.25 min, ultrasound irradiation power of 160 W and temperature of 332.19 K), the total yield of the 3 flavonoids were 100.93 ± 4.01 mg/g from the leaves of A. nephrolepis (with 31.03 ± 1.51 mg/g, 0.31 ± 0.01 mg/g, 69.59 ± 2.57 mg/g for taxifolin, diosmin, and quercetin, respectively), and under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 36.80 min, ultrasound irradiation power of 150 W and temperature of 328.78 K), 16.05 mg/g ± 0.38 mg/g were obtained from the bark of A. nephrolepis (with 1.44 ± 0.05 mg/g, 0.47 ± 0.01 mg/g, 14.14 ± 0.38 mg/g for taxifolin, diosmin, and quercetin, respectively), which were close to the prediction values.

Kinetic models of the extraction of vanillic acid from pumpkin seeds

Vanillic acid is used in the food industry and perfumery, and the optimization of its extraction process from the natural source is important for saving time and money. The presence of vanillic acid in pumpkin seeds was proven using HPLC analysis. Computational optimization of the extraction shows that for the concentration of ethanol 40% and solmodul: V/m=20, the optimum condition for the extraction of vanillic acid from pumpkin seeds was 100 min and 450C. The estimation of fitting for each kinetic model to the experimental kinetic data was performed using the root mean square, standard deviation, and the correlation coefficient. Ponomarev model was shown as the most suitable with the highest accuracy among the six considered kinetic models. The enthalpy and entropy changes were positive, while the Gibbs free energy was negative and decreased when temperature increased during the thermodynamic analysis. Therefore, the extraction of vanillic acid from pumpkin seeds was endothermic, spontaneous, and irreversible.

Ultrasonic Assisted Extraction of Paclitaxel from Taxus x media Using Ionic Liquids as Adjuvants: Optimization of the Process by Response Surface Methodology

(1) Background: Ionic liquids (ILs) are considered "green" solvents and have been widely used in the extraction and separation field in recent years; (2) Methods: In this study, some common ILs and functionalized magnetic ionic liquids (MILs) were used as adjuvants for the solvent extraction of paclitaxel from Taxus x media (T. x media) using methanol solution. The extraction conditions of methanol concentration, IL type and amount, solid-liquid ratio, extraction temperature, and ultrasonic irradiation time were investigated in single factor experiments. Then, three factors of IL amount, solid-liquid ratio, and ultrasonic irradiation time were optimized by response surface methodology (RSM); (3) Results: The MIL [C₄MIM]FeCl₃Br was screened as the optimal adjuvant. Under the optimization conditions of 1.2% IL amount, 1:10.5 solid-liquid ratio, and 30 min ultrasonic irradiation time, the extraction yield reached 0.224 mg/g; and (4) Conclusions: Compared with the conventional solvent extraction, this ultrasonic assisted extraction (UAE) using methanol and MIL as adjuvants can significantly improve the extraction yield, reduce the use of methanol, and shorten the extraction time, which has the potentiality of being used in the extraction of some other important bioactive compounds from natural plant resources.