[Application of microwave vacuum drying with process management in extract drying of personalized traditional Chinese medicine preparations].

Extracts are important intermediates in the production of traditional Chinese medicines preparations. The drying effect of extracts will directly affect the subsequent production process and the quality of the preparation. To meet the requirements of high drug loading, short time consumption, and simple production process of personalized traditional Chinese medicine preparations, this study explored the application of multi-program microwave vacuum drying process in the extract drying of personalized traditional Chinese medicine preparations. The influencing factors of microwave vacuum drying process were investigated for 5 excipients and 40 prescriptions. Taking the feasibility of drying, drying rate, drying time, and dried extract status as indicators, this study investigated the feeding requirements of microwave vacuum drying. With the dried extract status as the evaluation indicator, the three drying programs(A, B, and C) were compared to obtain the optimal drying condition. The experimental results showed that the optimal feeding conditions for microwave vacuum drying were material layer thickness of 2 cm and C program(a total of 7 drying processes), which solved the problem of easy scorching in microwave drying with process management. Furthermore, the preset moisture content of the dried extract in microwave drying should be 4%-5%, so that the dried extract of traditional Chinese medicine preparation had uniform quality, complete drying, and no scorching. This study lays a foundation for the application of microwave drying in the production of traditional Chinese medicine preparations, promoting the high-quality development of personalized traditional Chinese medicine preparations.

Differences in physicochemical properties of pectin extracted from pomelo peel with different extraction techniques.

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.

Microwave hyperthermia enhances radiosensitization by decreasing DNA repair efficiency and inducing oxidative stress in PC3 prostatic adenocarcinoma cells.

PURPOSE: Radiotherapy (RT) is the primary treatment for prostate cancer (PCa); however, the emergence of castration-resistant prostate cancer (CRPC) often leads to treatment failure and cancer-related deaths. In this study, we aimed to explore the use of microwave hyperthermia (MW-HT) to sensitize PCa to RT and investigate the underlying molecular mechanisms. METHODS: We developed a dedicated MW-HT heating setup, created an in vitro and in vivo MW-HT + RT treatment model for CRPC. We evaluated PC3 cell proliferation using CCK-8, colony experiments, DAPI staining, comet assay and ROS detection method. We also monitored nude mouse models of PCa during treatment, measured tumor weight, and calculated the tumor inhibition rate. Western blotting was used to detect DNA damage repair protein expression in PC3 cells and transplanted tumors. RESULTS: Compared to control, PC3 cell survival and clone formation rates decreased in RT + MW-HT group, demonstrating significant increase in apoptosis, ROS levels, and DNA damage. Lower tumor volumes and weights were observed in treatment groups. Ki-67 expression level was reduced in all treatment groups, with significant decrease in RT + MW-HT groups. The most significant apoptosis induction was confirmed in RT + MW-HT group by TUNEL staining. Protein expression levels of DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways significantly decreased in RT + MW-HT groups. CONCLUSION: MW-HT + RT treatment significantly inhibited DNA damage repair by downregulating DNA-PKcs, ATM, ATR, and P53/P21 signaling pathways, leading to increased ROS levels, aggravate DNA damage, apoptosis, and necrosis in PC3 cells, a well-established model of CRPC.

Sustainable green extraction of anthocyanins and carotenoids using deep eutectic solvents (DES): A review of recent developments.

Recently, deep eutectic solvents (DES) have been extensively researched as a more biocompatible and efficient alternative to conventional solvents for extracting pigments from natural resources. The efficiency of DES extraction for the anthocyanin and carotenoid can be enhanced by microwave-assisted extraction (MAE) and/or ultrasound-assisted extraction (UAE) techniques. Apart from the extraction efficiency, the toxicity and recovery of the pigments and their bioavailability are crucial for potential applications. A plethora of studies have explored the extraction efficiency, toxicity, and recovery of pigments from various natural plant-based matrices using DES. Nevertheless, a detailed review of the deep eutectic solvent extraction of natural pigments has not been reported to date. Additionally, the toxicity, safety, and bioavailability of the extracted pigments, and their potential applications are not thoroughly documented. Therefore, this review is designed to understand the aforementioned concepts in using DES for anthocyanin and carotenoid extraction.

Comparison evaluation pretreatments on the quality characteristics, oxidative stability, and volatile flavor of walnut oil.

In this study, we applied various thermal pretreatment methods (e.g., hot-air, microwave, and stir-frying) to process walnut kernels, and conducted comparative analysis of the physicochemical properties, nutritional components, in vitro antioxidant activity, and flavor substances of the extracted walnut oil (WO). The results indicated that, thermal pretreatment significantly increased the extraction of total trace nutrients (e.g., total phenols, tocopherols, and phytosterols) in WO. The WO produced using microwave had 2316.71 mg/kg of total trace nutrients, closely followed by the stir-frying method, which yielded an 11.22% increase compared to the untreated method. The WO obtained by the microwave method had a higher Oxidative inductance period (4.05 h) and oil yield (2.48%). After analyzing the flavor in WO, we found that aldehydes accounted for 28.77% of the 73 of volatile compounds and 58.12% of the total flavor compound content in microwave-pretreated WO, these percentages were higher than those recorded by using other methods. Based on the comprehensive score obtained by the PCA, microwave-pretreatment might be a promising strategy to improve the quality of WO based on aromatic characteristics.

Spatiotemporal modeling of nano-delivered chemotherapeutics for synergistic microwave ablation cancer therapy.

BACKGROUND AND OBJECTIVE: The effectiveness of current microwave ablation (MWA) therapies is limited. Administration of thermosensitive liposomes (TSLs) which release drugs in response to heat has presented a significant potential for enhancing the efficacy of thermal ablation treatment, and the benefits of targeted drug delivery. However, a complete knowledge of the mechanobiological processes underlying the drug release process, especially the intravascular drug release mechanism and its distribution in response to MWA needs to be improved. Multiscale computational-based modeling frameworks, integrating different biophysical phenomena, have recently emerged as promising tools to decipher the mechanobiological events in combo therapies. The present study aims to develop a novel multiscale computational model of TSLs delivery following MWA implantation. METHODS: Due to the complex interplay between the heating procedure and the drug concentration maps, a computational model is developed to determine the intravascular release of doxorubicin from TSL, its transvascular transport into the interstitium, transport in the interstitium, and cell uptake. Computational models can estimate the interplays among liposome and drug properties, tumor perfusion, and heating regimen to examine the impact of essential parameters and to optimize a targeted drug delivery platform. RESULTS: Results indicated that the synergy of TSLs with MWA allows more localized drug delivery with lower side effects. The drug release rate and tumor permeability play crucial roles in the efficacy of TSLs during MWA treatment. The computational model predicted an unencapsulated drug lime around the ablated zone, which can destroy more cancer cells compared to MWA alone by 40%. Administration of TSLs with a high release rate capacity can improve the percentage of killed cancer cells by 24%. Since the heating duration in MWA is less than 15 min, the presented combination therapy showed better performance for highly permeable tumors. CONCLUSION: This study highlights the potential of the proposed computational framework to address complex and realistic scenarios in cancer treatment, which can serve as the future research foundation, including advancements in nanomedicine and optimizing the pair of TSL and MWA for both preclinical and clinical studies. The present model could be as a valuable tool for patient-specific calibration of essential parameters.

Green Approach to Enhance the Recovery of Polyphenols from Blackcurrant and Bilberry Leaves: Evaluation of Microwave-Assisted and Pressurized Liquid Extraction.

The aim of the present study was to evaluate microwave-assisted (MAE) and pressurized liquid extraction (PLE) for the recovery of polyphenols from blackcurrant and bilberry leaves and the preservation of their antioxidant activity. The extractions were carried out varying the solvent/solid (SS) ratio, temperature and time. During MAE, increasing the SS ratio increased the polyphenol concentration in the extracts from blackcurrant and bilberry leaves, while increasing the temperature had a positive effect only on bilberry polyphenols. During PLE, only a temperature increase was a determining factor for the isolation of blackcurrant leave polyphenols. Based on polyphenol recovery, optimal extraction parameters were established resulting in a yield of 62.10 and 56.06 mg/g dw in the blackcurrant and bilberry MAE extracts and 78.90 and 70.55 mg/g dw in the PLE extracts. The optimized extracts were profiled by UPLC ESI MS2, and their antioxidant capacity was evaluated through FRAP, DPPH, ABTS and ORAC assays. The characterization of the extracts by UPLC ESI MS2 confirmed flavonols as the predominant compounds in both blackcurrant and bilberry leaves, while flavan-3-ols and procyanidins were the main compounds responsible for high antioxidant capacity as confirmed by the ABTS and ORAC assays. Due to the extract composition and antioxidant capacity, PLE proved to be a technique of choice for the production of blackcurrant and bilberry leave extracts with high potential for use as value-added ingredients in the food and nutraceutical industry.

Polyphenol recovery from sorghum bran waste by microwave assisted extraction: Structural transformations as affected by grain phenolic profile.

Sorghum milling waste stream (bran), contains diverse phenolic compounds with bioactive properties. The study determined the potential of microwave assisted extraction (MAE) to recover the bran phenolic compounds. Red, white, and lemon-yellow pericarp sorghum brans were subjected to MAE and phenolic yield and structural transformation vs conventional extraction (control) assessed by UPLC-MS/MS, Folin-Ciocalteu and Trolox equivalent antioxidant capacity methods. Phenols yield increased from 3.7-20.3 to 12.6-75.5 mg/g, while antioxidants capacity increased average 3.3X in MAE extracts vs controls. Hydroxycinnamic acids increased most dramatically (3.0-32X) in MAE extracts (0.08-2.64 to 2.57-8.01 mg/g), largely driven by release of cell-wall derived feruloyl- and coumaroyl-arabinose. MAE hydrolyzed flavonoid glycosides into aglycones, and depolymerized condensed flavonoid heteropolymers into flavanones, flavanols and (deoxy)anthocyanidins. Thus, MAE dramatically enhances yield of valuable phenolics from sorghum bran waste, but also alters the phenolic profile in ways that may influence their chemical and biological properties.

Optimization and characterization of chestnut shell pigment extract obtained microwave assisted extraction by response surface methodology.

The objective of this study is to find optimum conditions to valorize chestnut shell bioactive compounds with coloring pigments through microwave-assisted extraction. With this aim, response surface methodology with central composite design was used. Microwave power (800 W), extraction time (12 min) and solvent concentration (NaOH: 0.115 mol/L) were determined as the optimum conditions to maximize the responses like color value, total phenolic content and total antioxidant capacity. In the optimized extract (OE), characterization of brown melanin like pigments were assessed by Spectrophotometer, Fourier Transform Infrared Spectrometer and major phenolics were identified as; gallic acid, ellagic acid, protocatechuic acid, catechin, and epicatechin as 0.53, 0.48, 0.46, 0.46, 0.14 mg/g dried weight (dw) by High Performance Liquid Chromatography, respectively. In terms of antibacterial activity, OE inhibited the growth of Staphylococcus aureus. Consequently, chestnut shells were successfully processed into natural coloring agents that were possessing strong brown color properties as well as high bioactive potential.

Transformable Magnetic Liquid-Metal Nanoplatform for Intracellular Drug Delivery and MR Imaging-Guided Microwave Thermochemotherapy.

Improved techniques for the administration of chemotherapeutic drugs are required to enhance tumor therapy efficacy and reduce the side effects of chemotherapy due to insufficient targeting and limited intratumoral drug release. Controlled drug delivery systems combined with thermotherapy are expected to play an important role in personalized tumor therapy. Herein, a novel microwave-responsive transformable magnetic liquid-metal (MLM) nanoplatform is designed for effective endosomal escape that facilitates intracellular drug delivery and enhanced anticancer therapy. The MLM nanoplatform exhibits a sensitive magnetic resonance imaging function for imaging-guided therapy and brilliant synergistic effects of chemotherapy with microwave thermal therapy to kill tumor cells. Once endocytosed by targeted tumor cells, the deep penetration of microwave energy can be absorbed by the MLM nanoplatform to convert heat and reactive oxygen species, which induces the shape transformation from nanospheres to large rods, resulting in the physical disruption of the endosomal membrane for intracellular drug release. Furthermore, the MLM nanoplatform synergistic therapy could activate immunomodulatory effects by M1 macrophage polarization and T cell infiltration, thus inhibiting tumor growth and lung metastasis. This work based on microwave-driven transformable magnetic liquid-metal nanoplatform provides novel ways to precisely control drug delivery and high-efficiency cancer therapy.

Natural antioxidants (rosemary and parsley) in microwaved ground meat patties: effects of in vitro digestion.

BACKGROUND: Minimizing food oxidation remains a challenge in several environments. The addition of rosemary extract (150 mg kg-1) and lyophilized parsley (7.1 g kg-1) at equivalent antioxidant activity (5550 µg Trolox equivalents kg-1) to meat patties was assessed in terms of their effect during microwave cooking and after being subjected to an in vitro digestion process. RESULTS: Regardless of the use of antioxidants, cooking caused a decrease of the fat content as compared to raw samples, without noticing statistical differences in the fatty acid distribution between raw and cooked samples [44%, 47% and 6.8%, of saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), respectively]. However, the bioaccessible lipid fraction obtained after digestion was less saturated (around 34% SFA) and more unsaturated (35% MUFA +30% PUFA). Cooking caused, in all types of samples, an increased lipid [thiobarbituric acid reactive substances (TBARS)] and protein (carbonyls) oxidation values. The increase of TBARS during in vitro digestion was around 7 mg malondialdehyde (MDA) kg-1 for control and samples with parsley and 4.8 mg MDA kg-1 with rosemary. The addition of parsley, and particularly of rosemary, significantly increased the antioxidant activity (DPPH) of cooked and digested microwaved meat patties. CONCLUSION: Whereas rosemary was effective in minimizing protein oxidation during cooking and digestion as compared to control samples, parsley could only limit it during digestion. Lipid oxidation was only limited by rosemary during in vitro digestion. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Upcycling crab shell waste into biochar for treatment of palm oil mill effluent via microwave pyrolysis and activation.

The escalating consumer demand for crabs results in a growing amount of waste, including shells, claws, and other non-edible parts. The resulting crab shell waste (CSW) is disposed of via incineration or landfills which causes environmental pollution. CSW represents a potential biological resource that can be transformed into valuable resources via pyrolysis technique. In this study, microwave pyrolysis of CSW using self-purging, vacuum, and steam activation techniques was examined to determine the biochar production yield and its performance in treating palm oil mill effluent (POME). The biochar produced through microwave pyrolysis exhibits yields ranging from 50 to 61 wt%, showing a hard texture, low volatile matter content (≤34.1 wt%), and high fixed carbon content (≥58.3 wt%). The KOH-activated biochar demonstrated a surface area of up to 177 m2/g that is predominantly composed of mesopores, providing a good amount of adsorption sites for use as adsorbent. The biochar activated with steam removed 8.3 mg/g of BOD and 42 mg/g of COD from POME. The results demonstrate that microwave pyrolysis of CSW is a promising technology to produce high-quality biochar as an adsorbent for POME treatment.

Improvement of the production of bio-oil and biodiesel from Egyptian Jatropha seeds by using microwave and ultrasonic.

Bio-diesel is used for engine as a replacement of diesel fuel which is characterized by lower emission, low pollution and renewable some of fuel. This study focus on how to enhance the production of bio-oil from Jatropha seeds by using microwave and ultrasonic as pre-treatments. To achieve that, the effects of extraction temperature (60, 80, 100 and 120 °C) and extraction screw speed (60, 90 and 120 rpm) on oil extraction yield and quality, extraction energy requirements and extraction time and were studied. Studying the effect of pretreatments by microwave and ultrasonic on the yield, energy and time of extraction were studied. The results most important indicate that the highest oil yield (25.1%) was recorded at 120 °C extraction temperature and 60 rpm screw speed. The energy required for extraction ranged from 8 to 11.5 W.h depending on temperature and speed of extraction. The results indicated that using both pretreatments improve the oil yield by 5.03% for microwave and by 6.75% for ultrasonic. Finally, the results concluded that to produce 1 kg of biodiesel you need 1.1 kg raw oil and consume from 2052.5 W.h energy requirement.

Fundamental properties and phosphorus transformation mechanism of soybean straw during microwave hydrothermal conversion process.

Microwave hydrothermal (MHT) conversion is emerging as a promising technology for the disposal and reutilization of biowastes. This study investigated the fundamental properties and phosphorus transformation mechanism of soybean straw during the MHT conversion process. The oxygen-containing functional groups in soybean straw were stripped, and a trend of dehydration was observed as the temperature increased during the MHT process. Cellulose was identified as the major component of the MHT solid products at high temperature. Glucose and glucuronic acid in the MHT liquid products were gradually converted to formic acid and acetic acid with increasing temperature and holding time. The characteristics of the MHT products directly affected the changes in P speciation and transformation. Most of the P was distributed in liquid products and the impact of holding time was not significant on P distribution at low MHT temperature. With the increase in temperature and holding time, P gradually transferred into the solid products. The proportion of organic phosphorus and soluble inorganic phosphorus in soybean straw was high, and it decreased noticeably after the MHT process. The increase in MHT temperature promoted the conversion of OP and AP into IP and NAIP respectively. P K-edge X-ray absorption near edge structure analysis reveals that Ca5(PO4)3(OH) was the major component of soybean straw and more Ca5(PO4)3(OH) was formed at lower MHT temperature. This study provides fundamental knowledge on the property changes of soybean straw and the transformation of phosphorus during MHT conversion process, which is essential for its disposal and further utilization.

Magnetic Bimetallic Heterointerface Nanomissiles with Enhanced Microwave Absorption for Microwave Thermal/Dynamics Therapy of Breast Cancer.

Microwave thermotherapy (MWT) has shown great potential in cancer treatment due to its deep tissue penetration and minimally invasive nature. However, the poor microwave absorption (MA) properties of the microwave thermal sensitizer in the medical frequency band significantly limit the thermal effect of MWT and then weaken the therapeutic efficacy. In this paper, a Ni-based multilayer heterointerface nanomissile of MOFs-Ni-Ru@COFs (MNRC) with improved MA performance in the desired frequency band via introducing magnetic loss and dielectric loss is developed for MWT-based treatment. The loading of the Ni nanoparticle in MNRC mediates the magnetic loss, introducing the MA in the medical frequency band. The heterointerface formed in the MNRC by nanoengineering induces significant interfacial polarization, increasing the dielectric loss and then enhancing the generated MA performance. Moreover, MNRC with the strong MA performance in the desired frequency range not only enhances the MW thermal effect of MWT but also facilitates the electron and energy transfer, generating reactive oxygen species (ROS) at tumor sites to mediate microwave dynamic therapy (MDT). The strategy of strengthening the MA performance of the sensitizer in the medical frequency band to improve MWT-MDT provides a direction for expanding the clinical application of MWT in tumor treatment.

A two-stage exacerbated hypoxia nanoengineering strategy induced amplifying activation of tirapazamine for microwave hyperthermia-chemotherapy of breast cancer.

Microwave hyperthermia (MH) is an emerging treatment for solid tumors, such as breast cancer, due to its advantages of minimally invasive and deep tissue penetration. However, MH induced tumor hypoxia is still an obstacle to breast tumor treatment failure. Therefore, an original nanoengineering strategy was proposed to exacerbate hypoxia in two stages, thereby amplifying the efficiency of activating tirapazamine (TPZ). And a novel microwave-sensitized nanomaterial (GdEuMOF@TPZ, GEMT) is designed. GdEuMOF (GEM) nanoparticles are certified excellent microwave (MW) sensitization performance, thus improving tumor selectivity to achieve MH. Meanwhile MW can aggravate the generation of thrombus and caused local circulatory disturbance of tumor, resulting in the Stage I exacerbated hypoxia environment passively. Due to tumor heterogeneity and uneven hypoxia, GEMT nanoparticles under microwave could actively deplete residual oxygen through the chemical reaction, exacerbating hypoxia level more evenly, thus forming the Stage II of exacerbated hypoxia environment. Consequently, a two-stage exacerbated hypoxia GEMT nanoparticles realize amplifying activation of TPZ, significantly enhance the efficacy of microwave hyperthermia and chemotherapy, and effectively inhibit breast cancer. This research provides insights into the development of progressive nanoengineering strategies for effective breast tumor therapy.

Effects of microwave drying on physicochemical characteristics, microstructure, and antioxidant properties of propolis extract.

BACKGROUND: The heat sensitivity of phenolics and flavonoids leads to considerable losses of these compounds during conventional drying. Microwave drying has the advantage of shorter drying time and rigorous process control, minimizing damage to heat-sensitive compounds. Microwave drying kinetics and the impacts of microwave drying on physicochemical characteristics, morphological structure, antioxidant properties, total phenolics, and flavonoid content of propolis extract were investigated. RESULTS: Increasing the microwave power output from 180 to 900 W resulted in a 67% reduction in drying time. Morphological changes were more noticeable at higher microwave power levels as shown in scanning electron microscopy images. Water activity values of microwave dried propolis extracts were below 0.4, which satisfied the requirement for shelf-stable dry products. The solubility of microwave dried propolis extract increased with increasing microwave power level, and the highest solubility was achieved for the propolis extract microwave dried at 900 W. Microwave dried propolis extracts exhibited lower total phenolic content levels than fresh propolis extract. The microwave power level did not affect the total flavonoid content but it affected 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity of microwave dried propolis extracts. The DPPH free-radical scavenging activity closest to the fresh propolis extract was obtained for the microwave dried propolis extract at 900 W. This also showed the highest 6-hydroxy-2,5,7,8-tetramethyl-2-carboxylic acid (Trolox) equivalent antioxidant capacity. CONCLUSION: Microwave drying of propolis extract at 900 W was found to be the most efficient drying condition because it yielded the shortest drying time, the highest effective moisture diffusivity, and phenolic and flavonoid content levels that were very similar to those in fresh propolis extract. © 2023 Society of Chemical Industry.

Extraction of functional natural products employing microwave-assisted aqueous two-phase system: application to anthocyanins extraction from mulberry fruits.

Aqueous two-phase extraction (ATPE) has been extensively utilized for the extraction and separation of tiny-molecule substances as a new system (system with short-chain ethanol and inorganic salts). In this study, an innovative method of extracting anthocyanins from mulberry was developed, employing microwave-assisted extraction with ethanol/ammonium sulfate as a biphasic extractant. Response surface methodology (RSM) was utilized to optimize anthocyanin extraction conditions: 39% ethanol (w/w), 13% ammonium sulfate (w/w), and liquid-to-solid ratio of 45:1, microwave duration 3 min, microwave temperature 32 °C, and microwave power 480 Watt (W). High-performance liquid chromatography (HPLC) analysis demonstrated no significant differences in the structure of mulberry anthocyanins before and after MAATPE treatment, furthermore. The extraction behavior of MAATPE was due to hydrogen bonding, according to Fourier transform infrared spectroscopy (FT-IR). Scanning electron microscopy analysis found that MAATPE damaged the cell structure via a microwave enhancement effect, which was more favorable to anthocyanin dissolution than standard extraction methods. The DPPH free radical scavenging rate of mulberry extracts at 0.5 mg/mL was higher than that of vitamin C (96.4 ± 0.76%), and the ABTS free radical scavenging rate (82.52 ± 2.13%) was close to that of vitamin C, indicating that MAATPE-derived mulberry extracts have good antioxidant activity.

A Smart Bacteria-Capture-Killing Vector for Effectively Treating Osteomyelitis Through Synergy Under Microwave Therapy.

Osteomyelitis caused by deep tissue infections is difficult to cure through phototherapy due to the poor penetration depth of the light. Herein, Cu/C/Fe3O4-COOH nanorod composites (Cu/C/Fe3O4-COOH) with nanoscale tip convex structures are successfully fabricated as a microwave-responsive smart bacteria-capture-killing vector. Cu/C/Fe3O4-COOH exhibited excellent magnetic targeting and bacteria-capturing ability due to its magnetism and high selectivity affinity to the amino groups on the surface of Staphylococcus aureus (S. aureus). Under microwave irradiation, Cu/C/Fe3O4-COOH efficiently treated S. aureus-infected osteomyelitis through the synergistic effects of microwave thermal therapy, microwave dynamic therapy, and copper ion therapy. It is calculated the electric field intensity in various regions of Cu/C/Fe3O4-COOH under microwave irradiation, demonstrating that it obtained the highest electric field intensity on the surface of copper nanoparticles of Cu/C/Fe3O4-COOH due to its high-curvature tips and metallic properties. This led to copper nanoparticles attracted more charged particles compared with other areas in Cu/C/Fe3O4-COOH. These charges are easier to escape from the high curvature surface of Cu/C/Fe3O4-COOH, and captured by adsorbed oxygen, resulting in the generation of reactive oxygen species. The Cu/C/Fe3O4-COOH designed in this study is expected to provide insight into the treatment of deep tissue infections under the irradiation of microwave.

Phytochemical compounds with promising biological activities from Ascophyllum nodosum extracts using microwave-assisted extraction.

Phytochemical-rich antioxidant extracts were obtained from Ascophyllum nodosum (AN) using microwave-assisted extraction (MAE). Critical extraction factors such as time, pressure, and ethanol concentration were optimized by response surface methodology with a circumscribed central composite design. Under the optimal MAE conditions (3 min, 10.4 bar, 46.8 % ethanol), the maximum recovery of phytochemical compounds (polyphenols and fucoxanthin) with improved antioxidant activity from AN was obtained. In addition, the optimized AN extract showed significant biological activities as it was able to scavenge reactive oxygen and nitrogen species, inhibit central nervous system-related enzymes, and exhibit cytotoxic activity against different cancer cell lines. In addition, the optimized AN extract showed antimicrobial, and anti-quorum sensing activities, indicating that this extract could offer direct and indirect protection against infection by pathogenic microorganisms. This work demonstrated that the sustainably obtained AN extract could be an emerging, non-toxic, and natural ingredient with potential to be included in different applications.