Separation and Purification of Two Saponins from Paris polyphylla var. yunnanensis by a Macroporous Resin

An effective method for separating and purifying critical saponins (polyphyllin II and polyphyllin VII) from a Paris polyphylla var. yunnanensis extract was developed in this study which was environmentally friendly and economical. Static adsorption kinetics, thermodynamics, and the dynamic adsorption-desorption of macroporous resins were investigated, and then the conditions of purification and separation were optimized by fitting with an adsorption thermodynamics equation and a kinetic equation. Effective NKA-9 resin from seven macroporous resins was screened out to separate and purify the two saponins. The static adsorption and dynamic adsorption were chemical and physical adsorption dual-processes on the NKA-9 resin. Under the optimum parameters, the contents of polyphyllin II and polyphyllin VII in the product were 17.3-fold and 28.6-fold those in plant extracts, respectively. The total yields of the two saponins were 93.16%. This research thus provides a theoretical foundation for the large-scale industrial production of the natural drugs polyphyllin II and polyphyllin VII.

Optimization of Ultrasound-Assisted Cellulase Extraction from Nymphaea hybrid Flower and Biological Activities: Antioxidant Activity, Protective Effect against ROS Oxidative Damage in HaCaT Cells and Inhibition of Melanin Production in B16 Cells

In this study, ultrasonic-assisted cellulase extraction (UCE) was applied to extract flavonoids and polyphenols from the Nymphaea hybrid flower. The extraction conditions were optimized using the response surface method (RSM) coupled with a Box-Behnken design. The crude extract of Nymphaea hybrid (NHE) was further purified using AB-8 macroporous resins, and the purified extract (NHEP) was characterized by FTIR and HPLC. In vitro activity determination by chemical method showed that NHEP displayed strong free radical scavenging abilities against the DPPH and ABTS radicals, good reduction power, and hyaluronidase inhibition. The cell viability by CCK-8 assays showed that NHEP had no significant cytotoxicity for B16 and HaCaT cells when the concentration was below 100 μg/mL and 120 μg/mL, respectively. NHEP with a concentration of 20–160 μg/mL can more effectively reduce the ROS level in H₂O₂ damaged HaCaT cells compared with 10 μg/mL of VC. The 40 μg/mL of NHEP had similar activity against intracellular melanin production in the B16 melanoma cells compared with 20 μg/mL Kojic acid. Good activities of antioxidation, whitening and protective effect against H₂O₂-induced oxidative damage promote the potential for NHEP as a functional raw material in the field of cosmetics and medicine.

Macroporous resin-assisted enrichment, characterizations, antioxidant and anticandidal potential of phytochemicals from Trachyspermum ammi

Extract of de-oiled seeds of Trachyspermum ammi was purified using macroporous resins and the performance of three resins were evaluated to enrich major phytochemical component. A HPLC method has been developed to separate major phytochemical constituents in the crude (CTAE) and partially purified extracts (PTAE). Macroporous resin assisted enrichment and purification suggested XAD-16 as the most efficient (yield 29.8%) followed by XAD-7HP and Diaion HP-20. Concentrated PTAE was subjected to multiple preparative-TLC to afford three compounds, namely, rosmarinic acid-3-O-glucopyranoside (TA-1), kaempferol-(coumaroyl-glucosyl)-rhamnoside (TA-2) and quercetin-3-O-galactoside (TA-3). The structure of these compounds was elucidated from their corresponding spectroscopic characterizations in FT-IR, HR-MS, and partially by ¹ H NMR. Total phenolic and flavonoid contents of the extracts were determined. Antioxidant activity by DPPH and ABTS radical scavenging, CUPRAC assays indicated the highest antioxidant potential of CTAE. Among the compounds, TA-1 exhibited the highest scavenging activity in ABTS (IC₅₀ 33.41 µg/ml) and DPPH (IC₅₀ 69.23 µg/ml), however, relatively lower than CTAE. In vitro anti-candidal activity against virulent strains of Candida spp. revealed C. albicans 4718 as the most susceptible (23.9 µg/ml) to PTAE. PRACTICAL APPLICATIONS: Seeds of Trachyspermum ammi has been extensively investigated for volatile aromatic components of the essential oil. However, the de-oiled seeds have rarely been exploited for potential bioactive phenolics. The present investigation envisaged possible utilization of the de-oiled Trachyspermum seeds for its phenolic constituents, which could be used as natural antioxidant with additional benefits of anticandidal properties. Indeed, macroporous resin assisted enrichment and purification of extracts of T. ammi seeds generate valuable reference compounds, rosmarinic acid-3-O-glucopyranoside, kaempferol-(coumaroyl glucosyl)-rhamnoside, and quercetin-3-O-galactoside.

Preparation and characterization of young Prunus persica fruit fraction and its anti-inflammatory effect on a transgenic zebrafish model

Young Prunus persica fruits (YPF) contain substances that are distinct from those found in the mature fruits. Response surface methodology was used to explore the influences of extraction conditions including ultrasonic time (X₁), ethanol proportion (X₂), liquid-to-solid ratio (X₃) and temperature (X₄) on UV-absorbing components from YPF. To purify the extract, the adsorption/desorption properties of 280 nm-absorbing components on AB-8 resin were investigated. A total of 11 metabolites (amino acids, glycosylated amino acids and phenolics) were identified in the UV-absorbing fraction of YPF (YPF-F) based on LC-MS/MS assays. In a study of in vivo anti-inflammatory activity, YPF-F significantly decreased the number of inflammatory cells that migrated to the lateral line location in CuSO₄-induced transgenic fluorescent zebrafish. YPF should be utilized as a high value resource of functional foods.

Adsorption and Desorption Properties of Total Flavonoids from Oil Palm (Elaeis guineensis Jacq.) Mature Leaf on Macroporous Adsorption Resins

Three different macroporous resins (XAD7HP, DAX-8, and XAD4) were evaluated for their adsorption and desorption properties in preparing flavonoid-enriched oil palm (Elaeis guineensis Jacq.) leaf extract. The influences of initial concentration, solution pH, contact time, and desorption solvent (ethanol) concentration were determined by static sorption/desorption methods. The optimal condition for adsorption of flavonoids was achieved when the solution of the extract was adjusted to pH 7, reaching equilibrium after 1440 min at 298 K. The adsorption process was well described by a pseudo-second-order kinetics model, while the adsorption isotherm data fitted well with a Freundlich model. The adsorption by each resin was via an exothermic and physical adsorption process. Based on the static experiment results, XAD7HP was found to be the most appropriate adsorbent, while 80% ethanol was the best solvent for desorbent. Further evaluation of its dynamic adsorption and desorption characteristics on a packed glass column showed that XAD7HP could enrich the OPL total flavonoid content by a 3.57-fold increment. Moreover, UHPLC–UV/PDA and UHPLC–MS/MS analysis revealed that apigenin and luteolin derivatives were selectively adsorbed by XAD7HP. Additionally, both the crude OPL extract and the flavonoid-enriched fraction have good DPPH and NO free radical scavenging activities. Multiple interactions between the flavonoids and cross-linked polymeric XAD7HP resin through van der Waals forces and hydrogen bonding described the sorption processes. Therefore, by utilizing this method, the flavonoid-enriched fraction from crude OPL extract could be used as a potential bioactive ingredient in nutraceutical and pharmaceutical applications at minimum cost with optimum efficiency.

Separation and Enrichment of Three Coumarins from Angelicae Pubescentis Radix by Macroporous Resin with Preparative HPLC and Evaluation of Their Anti-Inflammatory Activity

In order to enrich and separate three coumarins (columbianetin acetate, osthole and columbianadin) from Angelicae Pubescentis Radix (APR), an efficient method was established by combining macroporous resins (MARs) with preparative high-performance liquid chromatography (PHPLC). Five different macroporous resins (D101, AB-8, DA-201, HP-20 and GDX-201) were used to assess the adsorption and desorption characteristics of three coumarins. The result demonstrated that HP-20 resin possessed the best adsorption and desorption capacities for these three coumarins. Moreover, the adsorption dynamics profiles of three coumarins were well fitted to the pseudo second order equation (R² > 0.99) for the HP-20 resin. The adsorption process was described by the three isotherms models including Langmuir (R² > 0.98, 0.046 ≤ R_L ≤ 0.103), Freundlich (R² > 0.99, 0.2748 ≤ 1/n ≤ 0.3103) and Dubinin Radushkevich (R² > 0.97). The contents of columbianetin acetate, osthole and columbianadin in the product were increased 10.69-fold, 19.98-fold and 19.68-fold after enrichment, respectively. Three coumarins were further purified by PHPLC and the purities of them reached above 98%. Additionally, the anti-inflammatory effects of these three coumarins were assessed by Lipopolysaccharide (LPS)-induced RAW 264.7 cells. It was found that the production of NO and MCP-1 was obviously inhibited by three coumarins. Columbianetin acetate, osthole and columbianadin could be used as potentially natural anti-inflammatory ingredients in pharmaceutical products. It was concluded that the new method combining MARs with PHPLC was efficient and economical for enlarging scale separation and enrichment of columbianetin acetate, osthole and columbianadin with anti-inflammatory effect from the APR extract.

Integrated extraction and purification of total bioactive flavonoids from Toona sinensis leaves

An integrated procedure was developed to extract and purify total flavonoids from Toona sinensis leaves for the first time, in which pressurized liquid extraction was performed in tandem with HPD100 macroporous resin column. Consequently, the total flavonoids can be extracted using 10% EtOH, and the recovery and purity of total flavonoids was 71.05% and 66.60%. Moreover, products of high quality were obtained in an environmentally friendly process with lower consumption of time and solvent. The results demonstrated that the integrated extraction-adsorption procedure was an efficient process for the preparation of total bioactive flavonoids from Toona sinensis leaves.

Partial Purification, Identification, and Quantitation of Antioxidants from Wild Rice (Zizania latifolia)

To provide further insights into the potential health-promoting antioxidants from wild rice (Zizania latifolia), which is an abundant but underutilized whole grain resource in East Asia, a partial purification based on D101 macroporous resin was carried out for the purification and enrichment of the antioxidants from the bioactive ethanol extracts of wild rice. On that basis, 34 phenolic compounds in the antioxidant fractions were identified by a high-performance liquid chromatography-linear ion trap quadrupole-Orbitrap-mass spectrometry (HPLC-LTQ-Orbitrap-MSⁿ). The results suggested that phenolic acids could be enriched in the 10% ethanol-eluted fraction whereas flavonoids (including procyanidins and flavonoid glycosides) could be enriched in 20⁻30% ethanol-eluted fractions. A quantitative analysis determined by the multiple reaction monitoring mode of the ultra-performance liquid chromatography-triple quadrupole-tandem mass spectrometry (UPLC-QqQ-MS/MS) revealed a high content of procyanidins in wild rice. Compared with phenolic acids, flavonoids may contribute more to the potent antioxidant activity of wild rice. This is the first study on the antioxidants from wild rice Z. latifolia. These findings provide novel information on the functional components of wild rice, and will be of value to further research and development on Z. latifolia.

Enrichment and Purification of the Bioactive Flavonoids from Flower of Abelmoschus manihot (L.) Medic Using Macroporous Resins

Flower of Abelmoschus manihot (FAM) is clinically effective to treat chronic kidney disease (CKD) with a relatively high dosage. To improve the efficacy and the compliance of patients, macroporous resins were adopted to enrich and purify flavonoids from FAM, which are thought to be the major renal protective constituents in FAM. After screening six different kinds of macroporous resins, HPD-100 was selected for its great adsorption and desorption capacity. Then, orthogonal design tests were used to optimize parameters in the processes of impurity removal and flavonoids of FAM desorption on column chromatogram. Moreover, process scale-up was performed, and purification effects maintained after amplification. After purification, the content of seven main flavonoids in the product increased from 8.29% to 51.43%. Protective and anti-inflammatory effects of crude extract and the flavonoid component of FAM after purification were investigated on the adriamycin-damaged HK-2 cells and lipopolysaccharide-stimulated Raw 264.7 cells models. Both bioactivities were improved greatly after purification for these two cell models. Therefore, the purification process had enriched the main bioactive constituents with potential alleviating kidney injury activities. The flavonoid component of FAM is worthy of being developed as an improved remedy for CKD with better patients' compliance.

Preparative separation of phloridzin from apple leaves using macroporous resins followed by preparative high-performance liquid chromatography

Phloridzin is one of the major phenolic compounds in apple and has been widely used in medicine for a long time due to its significant biomedical activities. In this article, macroporous resin was used for purification of phloridzin from apple leaves. The HPD-300 resin was selected for the enrichement of phloridzin according to its high adsorption and desorption capacities. The adsorption kinetics and isotherms were constructed on the HPD-300 resin and fitted well to the pseudo-second-order kinetic model and Langmuir model, respectively. Dynamic adsorption and desorption tests were performed on the column packed with HPD-300 resin to optimize the operating parameters. After one round treatment with HPD-300 resin, the purity of phloridzin in the product increased from 11.4 to 50.1% with a recovery yield of 79.3%. Subsequently, preparative high-performance liquid chromatography was employed for the purification of phloridzin. The purity of phloridzin could reach above 98% after further recrystallization with a recovery yield of 75.8%.

Orthogonal strategy development using reversed macroporous resin coupled with hydrophilic interaction liquid chromatography for the separation of ginsenosides from ginseng root extract

Ginsenosides have been widely conceded as having various biological activities and are considered to be the active ingredient of ginseng. Nowadays, preparative high-performance liquid chromatography is considered to be a highly efficient method for ginseng saponins purification and preparation. However, in the process of practical application, due to the complex and varied composition of natural products and relatively simple pretreatment process, it is likely to block the chromatographic column and affect the separation efficiency and its service life. In this work, an orthogonal strategy was developed; in the first-dimension separation, reverse-phase macroporous resin was applied to remove impurities in ginseng crude extracts and classified ginseng extracts into protopanaxatriol and protopanaxadiol fractions. In the second-dimension separation, the obtained fractions were further separated by a preparative hydrophilic column, and finally yielded 11 pure compounds. Eight of them identified as ginsenoside Rh₁ , Rg₂ , Rd, Rc, Rb₂ , Rb₁ , Rg₁ , and Re by standards comparison and electrospray ionization mass spectrometry. The purity of these ginsenosides was assessed by high-performance liquid chromatography with UV detection.

Enrichment and Cytotoxic Activity of Curcuminoids from Turmeric Using Macroporous Resins

Curcuminoids are functional secondary metabolites abundant in turmeric. In the present study, a simple and efficient method for enrichment of curcuminoids from turmeric was developed using macroporous resin. Eight different types of macroporous resins were examined by static adsorption/desorption properties and the type of XDA-7 was selected as the optimum one. Under the optimized conditions, the final contents of refined extract excluded 84.2% of impurities, by comparison with crude extract in a scale-up experiment. Meanwhile, 8 representative curcuminoids including 4 dihydro- and tetrahydro-curcuminoids were enriched, isolated, and identified by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) data. In addition, the individual curcuminoids were prepared to evaluate their cytotoxic activity toward HeLa tumor cell lines. All compounds, especially the trace amount of curcuminoids, demonstrated notable cytotoxic activity. The results supported that those trace amount of curcuminoids can be good candidates for drug development as anticancer agents. The purification process was simple and efficient, which could afford a potential method to enrich and concentrate not only the major curcuminoids, but also the trace amount of ones from turmeric raw materials for industrial applications.

Preparative Separation and Purification of the Total Flavonoids in Scorzonera austriaca with Macroporous Resins

The use of macroporous resins for the separation and purification of total flavonoids to obtain high-purity total flavonoids from Scorzonera austriaca was studied. The optimal conditions for separation and purification of total flavonoids in S. austriaca with macroporous resins were as follows: D4020 resin columns were loaded with crude flavonoid extract solution, and after reaching adsorptive saturation, the columns were eluted successively with 5 bed volumes (BV) of water, 5 BV of 5% (v/v) aqueous ethanol and 5 BV of 30% (v/v) aqueous ethanol at an elute flow rate of 2 BV·h⁻¹. Total flavonoids were obtained from the 30% aqueous ethanol eluate by vacuum distillation recovery. The content of flavonoid compounds in the total flavonoids was 93.5%, which represents an improvement by about 150%. In addition, five flavonoid compounds in the product were identified as 2″-O-β-d-xylopyranosyl isoorientin, 6-C-α-l-arabipyranosyl orientin, orientin, isoorientin and vitexin by LC-ESI-MS analysis and internal standard methods. The results in this study could represent a method for the large-scale production of total flavonoids from S. austriaca.