Optimization for ultrasonic-microwave synergetic extraction of total iridoid glycosides and screening of analgesic and anti-inflammatory active fractions from patrinia scabra Bunge (Valerianaceae)

Background Patrinia scabra Bunge is a well-known herbal medicine for its favorable treatment on inflammatory diseases owing to its effective ingredients, in which iridoid glycoside plays an extremely significant role. This article aimed to improve the content of total iridoid glycosides in crude extract through a series optimization of extraction procedure. Moreover, considering that both pain and inflammation are two correlated responses triggered in response to injury, irritants or pathogen, the article investigated the anti-inflammatory and analgesic activities of P. scabra to screen out the active fraction. Method P. scabra was extracted by ultrasonic-microwave synergistic extraction (UMSE) to obtain total iridoid glycosides (PSI), during which a series of conditions were investigated based on single-factor experiments. The extraction process was further optimized by a reliable statistical method of response surface methodology (RSM). The elution fractions of P. scabra extract were prepared by macroporous resin column chromatography. Through the various animal experiment including acetic acid-induced writhing test, formalin induced licking and flinching, carrageenan-induced mice paw oedema test and xylene-induced ear edema in mice, the active fractions with favorable analgesic and anti-inflammatory effect were reasonably screen out. Results The content of PSI could reach up to 81.42 ± 0.31 mg/g under the optimum conditions as follows: ethanol concentration of 52%, material-to-liquid ratio of 1:18 g/mL, microwave power at 610 W and extraction time of 45 min. After gradient elution by the macroporous resin, the content of PSI increased significantly. Compared with other concentrations of elution liquid, the content of PSI in 30 and 50% ethanol eluate was increased to reach 497.65 and 506.90 mg/g, respectively. Owing to the pharmacology experiment, it was reasonably revealed that 30 and 50% ethanol elution fractions of P. scabra could relieve pain centrally and peripherally, exhibiting good analgesic and anti-inflammatory activities. Conclusion Patrinia scabra possessed rich iridoids and exhibited significant analgesic and anti-inflammatory activities.

Lab Scale Extracted Conditions of Polyphenols from Thinned Peach Fruit Have Antioxidant, Hypoglycemic, and Hypolipidemic Properties

Thinned peach polyphenols (TPPs) were extracted by ultrasonic disruption and purified using macroporous resin. Optimized extraction conditions resulted in a TPPs yield of 1.59 ± 0.02 mg GAE/g FW, and optimized purification conditions resulted in a purity of 43.86% with NKA-9 resin. TPPs composition was analyzed by UPLC-ESI-QTOF-MS/MS; chlorogenic acid, catechin, and neochlorogenic acid were the most abundant compounds in thinned peaches. Purified TPPs exhibited scavenging activity on DPPH, ABTS, hydroxyl radical, and FRAP. TPPs inhibited α-amylase and α-glucosidase by competitive and noncompetitive reversible inhibition, respectively. TPPs also exhibited a higher binding capacity for bile acids than cholestyramine. In summary, TPPs from thinned peaches are potentially valuable because of their high antioxidant, hypoglycemic, and hypolipidemic capacities, and present a new incentive for the comprehensive utilization of thinned peach fruit.

Protective Effect of Effective Components of Coreopsis tinctoria Nutt on Retinopathy of db/db Diabetic Mice

Objective. Diabetic retinopathy (DR) is one of the main diabetic microvascular complications in clinical practice, which features a complicated mechanism and insignificant efficacy. Therefore, it is urgent to find effective drugs. Xinjiang Coreopsis tinctoria Nutt is a rare alpine wild plant with unique effects and extremely high medicinal value. Preliminary studies have shown that it can reduce elevated blood sugar, unhealthy lipids, and antioxidants. This study was intended to investigate the protective effect of the effective components of Coreopsis tinctoria Nutt on the retinopathy of db/db diabetic mice and provide experimental basis for exploring the efficacy of Coreopsis tinctoria Nutt and the development of new drugs for the treatment of DR. Method. The db/db diabetic mouse models were used, and the effective components of Coreopsis tinctoria Nutt were obtained from Coreopsis tinctoria Nutt using macroporous resin enrichment method after alcohol extraction. These mice were divided into the normal group, model group, and high-dose Coreopsis tinctoria Nutt groups, the positive drug metformin group, and the metformin and Coreopsis tinctoria Nutt combination group. After these db/db type 2 diabetes mouse models were intervened for 10 weeks, their weight, blood sugar, glycosylated hemoglobin, serum MDA, SOD, and other indicators of each group were tested, and the expression changes of VEGF, ICAM1, PEDF, Bcl-2 in mouse retina were observed by immunohistochemistry method. Result. The effective components of Coreopsis tinctoria Nutt were obtained using macroporous resin enrichment method after alcohol extraction, which were mainly comprised of chlorogenic acid, flavone mariside, mariside, dicaffeoyl quinic acid, and flavone oxanine, with a total content of 532.82 mg/g, and the total flavonoid content of 330 mg/g. The effective components of Coreopsis tinctoria Nutt significantly reduced blood sugar and glycosylated hemoglobin and improved oxidative stress levels in db/db diabetic mice. Meanwhile, they reduced the expression of VEGF and ICAM1 in retinopathy and increased the expression of Bcl-2 and PEDF. The combination of Coreopsis tinctoria Nutt and metformin has the most significant effect. Conclusion. Coreopsis tinctoria Nutt can prevent and treat early diabetic retinopathy by affecting the expression of retinopathy-related factors.

The Separation and Purification of Ellagic Acid from Phyllanthus urinaria L. by a Combined Mechanochemical-Macroporous Resin Adsorption Method

Ellagic acid is a phenolic compound that exhibits both antimutagenic and anticarcinogenic activity in a wide range of assays in vitro and in vivo. It occurs naturally in some foods such as raspberries, strawberries, grapes, and black currants. In this study, a valid and reliable method based on mechanochemical-assisted extraction (MCAE) and macroporous adsorption resin was developed to extract and prepare ellagic acid from Phyllanthus urinaria L. (PUL). The MCAE parameters, acidolysis, and macroporous adsorption resin conditions were investigated. The key MCAE parameters were optimized as follows: the milling time was 5 min, the ball mill speed was 100 rpm, and the ball mill filling rate was 20.9%. Sulfuric acid with a concentration of 0.552 mol/L was applied for the acidolysis with the optimized acidolysis time of 30 min and acidolysis temperature of 40 °C. Additionally, the XDA-8D macroporous resin was chosen for the purification work. Both the static and dynamic adsorption tests were carried out. Under the optimized conditions, the yield of ellagic acid was 10.2 mg/g, and the content was over 97%. This research provided a rapid and efficient method for the preparation of ellagic acid from the cheaply and easily obtained PUL. Meanwhile, it is relatively low-cost work that can provide a technical basis for the comprehensive utilization of PUL.

Ultrasonic-Assisted Aqueous Two-Phase Extraction Combined with Macroporous Resin Enrichment of Lignans from Flaxseed Meal and Their Antioxidant Activities

Background Secoisolariciresinol di glucoside (SDG) is a natural antioxidant generally extracted from flaxseed, which is one of the most important oil crops in China, the by-product of the flaxseed oil, i.e., flaxseed meal, still contains a lot of lignans. However, flaxseed meal is generally treated as waste, resulting in a huge waste of resources. Objective To establish an efficient and convenient method for extraction and purification of lignans from flaxseed meal. Methods First, we used response surface methodology (RSM) to optimize the extraction conditions of the ultrasonic-assisted aqueous two-phase system (UAATPS), and we obtained the purified extracts by macroporous resin purification (MRP). Second, the antioxidant ability of the extracts was studied in vitro. Results The best extraction conditions obtained were as follows: 9.0 wt% sodium hydroxide, 30.0 wt% isopropanol, extraction time 39 min, liquid-to-solid ratio of 52.0 mL/g, ultrasonic wave 560 W, and extraction temperature 40 °C. Under the optimal conditions, the purity of crude extracts (SDG-APTS-C) reached 21.5%. The desorption conditions of MRP were as follows: eluting 3 BV with ultrapure water, and then eluting with 25% ethanol at 2 BV/h to collect eluents. The purified extracts (SDG-ATPS-P) had a purity quotient of 73.9%, 52.4% higher than that of SDG-ATPS-C. Additionally, experiments conducted in this paper revealed that SDG-ATPS-C and SDG-ATPS-P could effectively remove DPPH, ABTS, and hydroxyl free radicals in vitro. Conclusions The method was validated for extracting SDG from flaxseed meal, thus achieving the reuse of flaxseed meal. Highlights This research provides some references for the application of UAATPS combined with MRP in natural products.

Preparation of Hydroxytyrosol by Acid Hydrolysis from Olive Leaves

Hydroxytyrosol (HT) is the main bioactive compound in olive leaves. However, olive leaves contain a lower level of HT and the extraction process of HT was rarely optimized. In this study, compared with two extraction methods, ultrasound was found to have a positive effect on improving the yield of HT. Therefore, ultrasound was used to assist hydrolysis of hydrochloric acid to extract HT from olive leaves. Response surface method and macroporous resins were applied to optimize the extraction process as well as enrichment of HT. The results showed that ultrasonic extraction time had a significant effect on the yield and the optimal extraction conditions were obtained: ultrasonic time was 120 min, hydrochloric acid concentration was 1.60 mol/L and the liquid-to-material ratio was 60.00 mL/g. Under the optimal extraction condition, the yield of HT was 14.11 ± 0.12 mg/g. NKA-Ⅱ macroporous resin was proved to be a suitable resin to enrich HT from extraction solution. The optimal condition for enriching HY was 250 mL of loading solution at the flow rate of 1.5 mL/min with 40 mL volume of 75% ethanol–eluent at a flow rate of 1.0 mL/min. The concentration of HT changed from 2.27% to 9.25% after enrichment by macroporous resin.

Adsorption and Desorption Characteristics of Total Flavonoids from Acanthopanax senticosus on Macroporous Adsorption Resins

We examined the application of six different resins with the aim of selecting a macroporous resin suitable for purifying Acanthopanax senticosus total flavonoids (ASTFs) from Acanthopanax senticosus crude extract (EAS) by comparing their adsorption/desorption capacities, which led to the selection of HPD-600. Research on the adsorption mechanism showed that the adsorption process had pseudo-second-order kinetics and fit the Freundlich adsorption model. Moreover, the analysis of thermodynamic parameters indicated that the adsorption process is spontaneous and endothermic. The optimal conditions for purification of ASTFs were determined as sample pH of 3, 60% ethanol concentration, and 3 BV·h−1 flow rate, for both adsorption and desorption, using volumes of 2.5 and 4 BV, respectively. The application of macroporous resin HPD-600 to enrich ASTFs resulted in an increase in the purity of total flavonoids, from 28.79% to 50.57%. Additionally, the antioxidant capacity of ASTFs was higher than that of EAS, but both were lower than that of L-ascorbic acid. The changes in ASTFs compositions were determined using ultra-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS), with the results illustrating that the levels of seven major flavonoids of ASTFs were increased compared to that in the crude extract.