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Traditional Tibetan medicine is important for discovery of drug precursors. However, knowledge of the chemical composition of traditional Tibetan medicines is very limited due to the lack of appropriate chromatographic purification methods. In the present work, Salvia prattii was taken as an example, and an off-line hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography preparative method was developed for the purification of phenylpropanoids with high purity from a crude sample of Salvia prattii. Based on the separation results of four different chromatographic stationary phases, the first-dimensional preparation was performed on an XAmide preparative column with the crude sample concentration of 62.0 mg/mL, and five main fractions were obtained from the 12.4 g crude sample with a recovery of 54.8%. An XCharge C18 preparative column was applied in the second-dimensional preparation to further isolate the phenylpropanoids from the redissolved first-dimensional fractions with concentration of approximately 50.0 mg/mL. The purities of the phenylpropanoids isolated from the crude sample of Salvia prattii were higher than 98%, indicating that the method was efficient for the purification of phenylpropanoids with high purity from Salvia prattii. Additionally, this method showed great potential in the preparation of phenylpropanoids and can serve as a good example for the purification of phenylpropanoids from other plant materials. [ABSTRACT FROM AUTHOR]

Dracocephalum heterophyllum (DH) is a Chinese herbal medicine used in treating hepatitis. However, the protective effects and pharmacological mechanisms of DH in hepatitis are unknown. In this study, we found that pretreatment with DH extract significantly ameliorated liver injury and suppressed the production of inflammatory cytokines, including tumor necrosis factor (TNF-α) and interferon-γ (IFN-γ) in Concanavalin A- (ConA-) induced hepatitis (CIH). DH recruited more CD11b+ Gr1+ myeloid-derived suppressor cells (MDSCs) to the liver and suppressed infiltration of macrophages (Kupffer cells) in the liver. The present work explores DH as an effective hepatoprotective medicine to inhibit inflammation and liver injury caused by hepatitis. [ABSTRACT FROM AUTHOR]

• COX-2 immobilized silica was packed in affinity solid-phase extraction column. • Method of preparative HPLC guided by the ASPE-HPLC system was constructed. • Two COX-2 inhibitors were targeted isolated from P. hookeri with the method. • The method was valuable for obtaining COX-2 inhibitors in natural sources. Pterocephalus hookeri , a classical Tibetan herb, is mainly used to treat rheumatoid arthritis (RA) and contains various constituents potentially with cyclooxygenase-2 (COX-2) selective inhibition. A novel strategy for screening and target separating COX-2 inhibitors from the extracts of P. hookeri based on affinity solid-phase extraction (ASPE) column combined with preparative high-performance liquid chromatography (pre-HPLC) was successfully developed. The potential COX-2 inhibitors of P. hookeri were screened and recognized by the ASPE-HPLC system, which strategy is to analyze the compounds isolated by the ASPE column. Then, the active compounds were targeted separated by pre-HPLC according to real-time chromatograms. The control drugs celecoxib and glipizide were analyzed to verify the specificity and accuracy of the developed method. As a result, two pure compounds with COX-2 binding affinities were successfully separated from P. hookeri. They were characterized as swertisin and scopoletin using 1H- and 13C NMR spectroscopy, and the in vitro COX-2 inhibitory activities were verified. Compounds with COX-2 inhibitory activities could be screened and targeted separated from crude extracts by this strategy, which indicated that the proposed method was feasible, robust and effective for rapid separation of COX-2 inhibitors from natural products. [ABSTRACT FROM AUTHOR]

• Novel polyamide coupled with MCI GEL® CHP20P MPC was employed for the preparative separation of bergenin from Saxifraga atrata. • Polyamide MPC was successfully used in enrichment of bergenin target fraction. • MCI GEL® CHP20P MPC was perfectly used in solving purification of bergenin from the target fraction. • The bergenin with >99% purity was isolated from Saxifraga atrata for the first time. In this study, polyamide and MCI GEL® CHP20P were employed as stationary phases in medium pressure chromatography (MPC) for the efficient preparative separation of bergenin from Saxifraga atrata. Ethanol–water, methanol-water, and acetonitrile-water mobile phases all showed good enrichment capacity for bergenin fraction when polyamide was used as a stationary phase. After 5 cycles of polyamide MPC using acetonitrile/water, 1.2 g of bergenin fraction was isolated from 180 g Saxifraga atrata herb. Further purification of this fraction was conducted using MCI GEL® CHP20P styrene-divinylbenzene beads. The bergenin fraction was separated into two fractions, and after three runs of MPC, 714.2 mg of bergenin with purity above 99% was obtained. The results demonstrate that the combination of polyamide and styrene-divinylbenzene MPC can be utilized for preparative isolation of compounds from natural products with high yield and purity. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of Saussurea medusa Maxim. led to the isolation of eleven compounds, including neoechinulin A (1), 8-hydroxypinoresinol (2), caruilignan D (3), 7(S)-hydroxyarctigenin (4), pinoresinol (5), arctigenin (6), arctii (7), epipinoresinol (8), loliolide (9), apigenin (10), and luteolin (11). Their structures were elucidated by spectroscopic methods and comparison with previously reported spectral data. Among them, compounds 1 and 2 were firstly obtained from this species, compounds 3 and 4 were isolated from the genus Saussurea for the first time. Furthermore, the chemotaxonomic significance of these compounds was discussed in details. • Eleven compounds are yielded from the whole herbs of Saussurea medusa Maxim. • This is the first report of some compounds isolated from S. medusa and genus Saussurea. • Two lignans can be used as valuable chemotaxonomic markers of S. medusa. [ABSTRACT FROM AUTHOR]

Saussurea obvallata (S. obvallata) is widely used in Qinghai-Tibet Plateau with high medicinal and edible values of reducing inflammation. But, the individual components and mechanisms of action still ill-defined. In this work, an integrated method using affinity ultrafiltration combined with preparative liquid chromatography was developed to identify and separate cyclooxygenase-2 (COX-2) inhibitors from S. obvallata. The sample was pretreated using on-line medium pressure liquid chromatography to yield the active fraction. Then, the potential COX-2 ligands were screened out using affinity ultrafiltration from the targeted fraction and the identified compounds were isolated via preparative liquid chromatography. As a result, four main compounds, coniferin (1), syringin (2), roseoside (3) and grasshopper ketone (4) were targeted isolated with IC 50 values of 12.34 ± 1.81, 4.04 ± 0.43, 13.91 ± 2.46 and 7.97 ± 1.21 µM, respectively. Results of this work demonstrated that the developed strategy was effective for the targeted separation of COX-2 inhibitors from natural product extracts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Objective: To establish a quantitative method for determination of gallic acid, original catechins, catechins, chlorogenic acid, caffeic acid, syringic acid in Lycium ruthenicum., Method: The sample was separated on an ODS column (4. 6 mm x 250 mm, 5 pnm), eluted with methanol and water containing 0. 1% acid with detected wavelength at 280 nm, and flow rate at 1. 0 mL x min(-1)., Result: The linearity of six components were good (r = 0.9999). The average recoveries (n=5) of the six constituents were 97. 70% (RSD 2.3%), 99.64% (RSD 1.8%), 100.7% (RSD 2.1%), 99.98% (RSD 2.6%), 99.60% (RSD 2.2%), 99.04% (RSD 2.4%), respectively., Conclusion: The method is rapid and precise. It can be used for quality control of Lycium ruthenicum juice.