Homogenization-assisted cavitation hybrid rotation extraction and macroporous resin enrichment of dihydroquercetin from Larix gmelinii

Dihydroquercetin nanoparticles nasal gel is a promising formulation for amelioration of Alzheimer's disease

Dihydroquercetin is a natural flavonoid with anti-inflammatory, antioxidant, and neuroprotective activities. Dihydroquercetin exhibits a great neuroprotector promise in Alzheimer's disorder via preventing the aggregation of amyloid-beta-peptide-Aβ(1-42). The goal of the study was to create dihydroquercetin-loaded-chitosan nanoparticles (DHQ-CS NPs) loaded to a mucoadhesive, thermosensitive in-situ gel for direct nasal administration to cure Alzheimer's disorder. Loading drug in chitosan nanoparticles and incorporation into thermosensitive gel enhanced residence time and reduced mucociliary-clearance. Different in-vitro-physicochemical-characteristics of gels and nanoparticles-characterization were used to evaluate the formulations. The therapeutic effectiveness of DHQ-CS NPs gel was evaluated behaviorally, biochemically and histopathologically in Alzheimer's-rat-model compared to intranasal DHQ gel. The small particles-size was obtained = 235.3 nm of DHQ-CS NPs. The DHQ-CS NPs gel demonstrated a greater release rate compared to the raw DHQ gel. Additionally, the nasal-administration of the DHQ-CS NPs gel showed better In-vivo results compared to DHQ gel, through improvement of memory and learning deficits and also the exploratory behavior and new object memory in streptozotocin induced-Alzheimer rats. Biochemically, the intranasal DHQ-CS NPs gel, showed reduced both Aβ-protein formation and tau protein hyperphosphorylation, inhibition of acetylcholine esterase activity and oxidative stress in the brain with increase of total antioxidants in the brain and serum, compared to DHQ gel. Histopathologically, the DHQ-CS NPs nasal gel produced improvement in the hippocampal and cerebral cortex structures, being comparable to the normal group. Consequently, the intranasal DHQ-CS NPs loaded in-situ gel seems to be a promising therapeutic formulation for Alzheimer's disease medication.

Ozonation degradation of wastewater using rotational hydrodynamic cavitation reactor with a conical rotor

Water pollution caused by an abusive discharge of dye-containing wastewater leads to serious ecological risks. Conventional wastewater treatment methods have shortcomings of incomplete degradation, long-time treatment and secondary pollution. For the first time, a rotational hydrodynamic cavitation reactor (RHCR) equipped with a conical rotor has been designed to enhance the ozonation process for effective degradation of pollutants. The effects of rotational speed, discharge voltage, gas flow rate, liquid flow rate and initial pH on methylene blue (MB) degradation were deeply investigated. The optimised conditions were initial pH = 9, rotational speed = 1800 rpm, discharge voltage = 9.3 kV, gas flow rate = 60 mL/min and liquid flow rate = 80 mL/min. With the integration of ozonation and cavitation in RHCR, the MB degradation efficiency reached 95.2%, which was 15.6% higher than that of the individual ozonation method. The degradation process was proven to track the first-order kinetic model, with the reaction rate and synergy index were 0.232 min-1 and 1.78, respectively. Through the quenching experiments, it can be confirmed that the contribution proportion of hydroxyl radical during degradation was increased by 8.7% due to the enhancement of cavitation. A required energy consumption of 74.7 kWh/order/m3 and a total expense of 8.7 $/m3 were calculated. The energy consumption of the RHCR was approximately 80% lower than that of the recently reported degradation system combining ozonation and cavitation, with total expense reduced by 52%. The findings of this work provide a new water treatment method and offered theoretical references for the design of RHCR.

Adsorption and desorption characteristics of flavonoids from white tea using macroporous adsorption resin

White tea contains the highest flavonoids compared to other teas. While there have been numerous studies on the components of different tea varieties, research explicitly focusing on the flavonoid content of white tea remains scarce, making the need for a good flavonoid purification process for white tea even more important. This study compared the adsorption and desorption performance of five types of macroporous resins: D101, HP20, HPD500, DM301, and AB-8. Among the tested resins, AB-8 was selected based on its best adsorption and desorption performance to investigate the static adsorption kinetics and dynamic adsorption-desorption purification of white tea flavonoids. The optimal purification process was determined: adsorption temperature 25 °C, crude tea flavonoid extract pH 3, ethanol concentration 80 %, sample loading flow rate and eluent flow rate 1.5 BV/min, and eluent dosage 40 BV. The results indicated that the adsorption process followed pseudo-second-order kinetics. Under the above purification conditions, the purity of the total flavonoids in the purified white tea flavonoid increased from approximately 17.69 to 46.23 %, achieving a 2.61-fold improvement, indicating good purification results. The purified white tea flavonoid can be further used for nutraceutical and pharmaceutical applications.

Antioxidative and Antimicrobial Evaluation of Bark Extracts from Common European Trees in Light of Dermal Applications

Plant species have developed effective defense strategies for colonizing diverse habitats and protecting themselves from numerous attacks from a wide range of organisms, including insects, vertebrates, fungi, and bacteria. The bark of trees in particular constitutes a number of components that protect against unwanted intruders. This review focuses on the antioxidative, dermal immunomodulatory, and antimicrobial properties of bark extracts from European common temperate trees in light of various skin pathogens, wound healing, and the maintenance of skin health. The sustainability aspect, achieved by utilizing the bark, which is considered a byproduct in the forest industry, is addressed, as are various extraction methods applied to retrieve extracts from bark.

Solubility Enhancement of Dihydroquercetin via "Green" Phase Modification

Dihydroquercetin (DHQ) is a promising antioxidant for medical applications. The poor water solubility of this flavanonol at ambient conditions inhibits its implementation in clinical practice as an injectable dosage form. Thus, increasing water solubility is a critical step toward solving this problem. Herein we attempted to deal with this problem via DHQ phase modification while at the same time adhering to the principles of green chemistry as much as possible. Lyophilization is an appropriate method to achieve phase modification in an environment-friendly way. This method was employed to generate new phase modifications of DHQ that were then characterized. Mixtures of water with ethanol or acetonitrile were used as solvents for the preparation of the lyophilizates, DHQ_E, and DHQ_A, respectively. The results of dissolution testing of the obtained DHQ_E and DHQ_A demonstrated that the lyophilization increased water solubility at least 30-fold times. These new DHQ modifications were studied by scanning electron microscopy, mass-spectrometry, nuclear magnetic resonance spectroscopy, infrared spectroscopy, X-ray powder diffraction, and thermal analysis. Their solid-state phases were confirmed to differ from the initial DHQ substance without any changes in the molecular structure. Both DHQ_E and DHQ_A showed as high antioxidant activity as the initial DHQ. These data demonstrate the potential of DHQ_E and DHQ_A as active pharmaceutical ingredients for injectable dosage forms.

Production of Taxifolin from Astilbin by Fungal Biotransformation

Taxifolin is known to have multiple biological functions. It has been widely used as a multifunctional food additive, and consequently, the global demand for taxifolin is increasing. The main method for taxifolin production is an extraction from larch wood, but the global resources of larch are limited. Astilbin, taxifolin-3-o-rhamnoside, is abundant in many plants and much more readily available, meaning taxifolin can be obtained by deglycosylation of astilbin. In this study, a fungal strain, Aspergillus fumigatus SQH4, was isolated from an enrichment culture of Smilax glabra rhizome to achieve the deglycosylation reaction. A culture of SQH4, adjusted to pH 6.5, with 5 g/L astilbin achieved a yield of taxifolin of 91.3% after biotransformation for 14 h at 35 °C. These findings offer an alternative method for the production of taxifolin.

Green Extraction of Six Phenolic Compounds from Rattan (Calamoideae faberii) with Deep Eutectic Solvent by Homogenate-Assisted Vacuum-Cavitation Method

A homogenate-assisted vacuum-cavitation extraction (HVE) method with a “green” solvent (a deep eutectic solvent, DES) was developed to extract phenolic compounds from rattan (Calamoideae faberii). In this study, the optimum molar ratio of choline chloride (ChCl) and ethylene glycol (EG) was 1:3, the optimum volume ratio of ChCl-EG:H₂O was 6:4, the solid-liquid ratio of HVE was 1:15, and the extraction time of homogenate and vacuum-cavitation were 2.0 min and 25 min, respectively. Under the optimum parameters of HVE, the extraction yield of total phenolic content with ChCl-EG solution was 6.82 mg/g. The higher total phenolic content was detected in fruit tissues (seeds 81.24 ± 1.55 mg/g, episperm 43.21 ± 0.87 mg/g, and arillus 38.47 ± 0.74 mg/g), followed by in leaves (sheath 19.5 ± 0.38 mg/g and blade 17.81 ± 0.33 mg/g). In addition, the content of specific phenolic compounds in aqueous and DES extracts was determined. Chlorogenic acid was the most abundant phenol in most organs of the rattan plant. Gallic acid was mainly distributed in the arillus; protocatechuic acid was mainly distributed in the arillus, sheath, and blade; protocatechuic aldehyde was mainly distributed in the blade, seed, and sheath; (+)-catechins were mainly distributed in the episperm, seed, and sheath; and epigallocatechin gallate was mainly distributed in the blade. The recovery rates of gallic acid, protocatechuic acid, protocatechuic aldehyde, (+)-catechins, chlorogenic acid, and epigallocatechin gallate were 93.77%, 94.09%, 97.32%, 97.83%, 94.41%, and 92.47%, respectively, by AB-8 resin.