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This study explored the structures of three polysaccharides from Bupleurum chinense DC. (BCPRs), and evaluated their antioxidant and anti-aging properties. The HPGPC and ion chromatography analyses revealed that the molecular weights of the BCPRs ranged from 12.05 to 21.20 kDa, and were primarily composed of rhamnose, arabinose, xylose, galactose, glucose and galacturonic acid. Methylation and NMR studies identified 10 PMAAs, establishing the various backbones of BCPRs 1-3. BCPR-3 demonstrated potent antioxidant activities, including DPPH, ABTS, hydroxy, and superoxide radicals scavenging in vitro. At concentrations between 125 and 500 μg/mL, BCPR-3 increased T-AOC, SOD and GSH-Px activities, while decreasing MDA levels in H 2 O 2 -induced SH-SY5Y cells. In addition, RNA-seq results indicated that BCPR-3 considerably downregulated the expression of 49 genes and upregulated five genes compared with the control group. KEGG analysis suggested that these differentially expressed genes (DEGs) were predominantly involved in the TNF and PI3K/Akt signaling pathways. Furthermore, in vivo experiment with Drosophila melanogaster showed that BCPR-3 could extend the average lifespan of flies. In conclusion, polysaccharides from B. chinense exhibited potential antioxidant and anti-aging activities, which could be developed as new ingredients to combat oxidative stress damage and slow the aging process., Competing Interests: Declaration of competing interest The authors have declared that no competing interests exist., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Selenium-containing polysaccharides have potential as an organic selenium dietary supplement, owing to their low toxicity, few side effects, and easy absorption attributes. In this study, we isolated two novel homogeneous selenium-containing polysaccharides from Rosa laevigata Michx fruits (Se-RLFPs). Results from primary structural analysis revealed that Se-RLFPs were α - pyranose, and were both composed of rhamnose, xylose, glucose with an average molecular weight of 24 and 16 KDa, respectively. Selenium contents in Se-RLFP-I and Se-RLFP-II were 16.49 μg/g and 21.61 μg/g, respectively. Results from analysis of antioxidant and neuroprotective activity of the polysaccharides revealed that Se-RLFPs had a radical scavenging effect. Specifically, they effectively protected SH-SY5Y cells from H 2 O 2 -induced damage by enhancing antioxidant enzyme activities (SOD), total antioxidant capacity (T-AOC) and suppressing malondialdehyde (MDA) levels. Western blots showed that the underlying mechanisms of action may be related to the Nrf2/HO-1 signaling pathway. Taken together, these results suggested that Se-RLFPs have potential as a pharmaceutical agent for treatment of neurodegenerative diseases (NDDs) or as a selenium-complementary ingredient in functional foods., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Hot water extraction and chromatographic purification methods were used to extract and purify two polysaccharides (RAPS-1 and RAPS-2) from the roots of alfalfa. Subsequently, RAPS-2 was modified using the HNO 3 /Na 2 SeO 3 method to obtain Se-RAPS-2. The structural features, antioxidant and in vitro anti-tumor activities of the three polysaccharides were evaluated. The structural analysis revealed that RAPS-1 (Mw = 10.0 kDa) was composed of rhamnose, xylose, arabinose, galacturonic acid, mannose and glucose, whereas RAPS-2 (Mw = 15.8 kDa) consisted of rhamnose, xylose, galacturonic acid, mannose, glucose and galactose. RAPS-1 contained 1 → 2, 1 → 4, 1 → 3, and 1 → 6 or 1 → glycosidic bonds; however, while RAPS-2 lacked 1 → 4 glycosidic linkages. The molecular weight of Se-RAPS-2 was 11.0 kDa less than that of RAPS-2. The results of activities demonstrated that Se-RAPS-2 displayed superior antioxidant activity and inhibitory effect in HepG2 cells than RAPS-1 and RAPS-2., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled, “Structural features, selenization modification, antioxidant and anti-tumor effects of polysaccharides from alfalfa roots”., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Medicago Sativa L., a nutrient-rich plant used as feed for cattle and sheep, is widely planted globally. This study investigated the structural characteristics and activities of three kinds of novel polysaccharides (APS1, APS2 and APS3) isolated from the stems of M. sativa as well as its two selenium modified products (Se-APS2 and Se-APS3). APS1 (Mw = 13.4 KDa) and APS2 (Mw = 11.2 KDa) were composed of rhamnose, arabinose, mannose and galactose with different molar ratio, APS3 (Mw = 18.6 KDa) was composed of rhamnose, arabinose, fructose, mannose and galactose. All APS1-3 contained 1 → 3 : 1 → 6 : 1 → 4 : 1 → 2 glycosidic bonds in a ratio of 0.74:0.09:0.05:0.12, 0.34:0.20:0.36:0.10 and 0.63:0.17:0.06:0.14, respectively. The selenium content of Se-APS2 (Mw = 9.0 KDa) and Se-APS3 (Mw = 10.2 KDa) were 1.05 and 2.57 µg/mg, respectively. Their surface morphology and thermal stability were determined by scanning electron microscope (SEM) and thermal analysis (TGA), respectively. Further, the antioxidant and neuroprotective activities of the three natural polysaccharides and two Se-polysaccharides were studied. Interestingly, Se-polysaccharides not only exhibited higher antioxidant activity, but also higher neuroprotective activity compared to natural polysaccharides., Competing Interests: Declaration of Competing Interest The authors have declared that no competing interests exist., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Xanthine oxidase (XO) has emerged as an important target for the treatment of hyperuricemia and gout. In this study, to obtain novel nonpurine XO inhibitors, a series of 1-alkyl-5/6-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)-1H-indole-3-carbonitriles (1a-1u, 2c, 2e, 2h and 2n) were designed using a bioisosteric replacement strategy and were synthesized through a five-step procedure with good yields. Thereafter, the in vitro XO inhibitory potencies of these compounds were evaluated by spectrophotometry, showing inhibitory profiles in the micromolar/submicromolar range. Particularly, compound 1h emerged as the strongest XO inhibitor, with an IC 50 value of 0.36 μM, which was approximately 21-fold more potent than the positive control allopurinol. Additionally, the structure-activity relationships revealed that the 5-oxo-4,5-dihydro-1,2,4-oxadiazole moiety linked at the 5-position of the indole scaffold was more preferable than the 6-position for the XO inhibitory potency. Enzyme kinetic studies indicated that compound 1h acted as a mixed-type XO inhibitor. Moreover, molecular modeling studies were performed on compound 1h to gain insights into its binding modes with XO. The results showed that the 5-oxo-4,5-dihydro-1,2,4-oxadiazole moiety could interact with Arg880 and Thr1010 in the innermost part of the active pocket through hydrogen bonds, while the cyano group could form hydrogen bonds with Asn768 and Lys771 in the subpocket. Furthermore, the in vivo hypouricemic effect of compound 1h was further investigated in a hyperuricemia rat model induced by potassium oxonate. The results suggested that compound 1h could effectively reduce serum uric acid levels at an oral dose of 10 mg/kg. Therefore, compound 1h could be a promising lead compound for the treatment of hyperuricemia and gout., 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 © 2020 Elsevier Masson SAS. All rights reserved.)

Three new pentacyclic triterpenoid saponins (1-3), together with medicagenic acid (4) were isolated and purified from 70% EtOH extract of Medicago sativa L. by different column chromatographic and semi-preparative HPLC. Their structures were established by direct interpretation of their spectral data, mainly HR-ESI-MS, 1D-NMR, 2D-NMR, and chemical methods, as well as comparison with literature data. Additionally, all isolates were evaluated for their neuroprotective activities against H 2 O 2 -induced damage in human neuroblastoma SHSY5Y cells. As a results, compounds 1 and 2 (67.14% and 73.05%) exhibited potent neuroprotective activities. These findings provide new insights into developing better treatment of neurodegenerative diseases for M. sativa in the future., (Copyright © 2020. Published by Elsevier Ltd.)

Breast cancer remains the most commonly diagnosed malignancy among women, which is frequently associated with adverse side-effects and high metastasis. Bupleurum chinense DC. has been empirically and extensively used as the core prescription for more than half of Chinese formulations for the adjuvant therapy of breast cancer, and its biological activity against breast cancer has been proven by both in vitro and in vivo experiments. Saikosaponin compounds are the characteristic constituent of B. chinense , which exhibit significant cytotoxicity toward several cancer cells. However, the specific mechanisms of these compounds in the treatment of breast cancer have not been comprehensively understood. Therefore, we aimed to determine more potentially therapeutic targets and investigate the biological mechanisms of B. chinense . In the present study, we adopted network pharmacology and bioinformatics analysis to facilitate this requirement. Consequently, the network analysis revealed that saikosaponin-f (39), saikosaponin-d (14), saikosaponin-c (26), saikosaponin-h (54), saikosaponin-g (41), 3'',6''- O -diacetylsaikosaponin-d (20), 11α-methoxy-saikosaponin-f (40), and 6''- O -acetylsaikosaponin-b 1 (48) might play important roles in the treatment of breast cancer. In addition, the apoptosis regulator Bcl-2 (BCL-2), C-X-C chemokine receptor type 4 (CXCR4), probable ATP-dependent RNA helicase DDX5 (DDX5), protein kinase C alpha (PRKCA), and proto-oncogene tyrosine-protein kinase Src (SRC) were the potential therapeutic targets that exhibited intense interactions. Mechanistically, a gene enrichment analysis revealed that the action of B. chinense against breast cancer was achieved by the regulation of several biological signaling pathways, such as pathways in cancer, PI3K-Akt signaling pathway, EGFR tyrosine kinase inhibitor resistance, microRNAs in cancer, etc. More importantly, we verified that the predictions involving saikosaponin-d by the cytotoxicity assay, apoptosis analysis, and RNA sequencing methods were partly consistent with those obtained from the network pharmacology prediction., Competing Interests: The authors declare that they have no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Rosa laevigata fruit, at present, is becoming increasingly popular as a functional foodstuff with several nutritional and medicinal properties. To explore the acetylcholinesterase (AChE) inhibitory activity of extracts from the Rosa laevigata Michx. fruit (RLMF), a simple and efficient enrichment purification technology based on microwave-assisted extraction (MAE) and multi vacuum extraction columns (VEC) was applied to screen and identify triterpenoids (TTs) in the RLMF extracts. The MAE conditions were optimized using the Box-Behnken design (BBD) with a quadratic regression model and the response surface method (RSM). The optimum conditions were as follows: ethanol concentration, 69%; extraction time, 12 min; ratio of liquid to raw material, 26 : 1 mL g -1 ; and microwave power, 528 W. Under these conditions, the maximum content of triterpenoids reached 62.48 ± 0.25 mg g -1 , which was close to the predicted value of 62.69 mg g -1 . In addition, two pure polyhydroxy triterpenoids: 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid (1) and 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid-28- O -β-d-glucopyrannoside (2) were isolated and enriched to more than 500 mg by a multi VEC method. Furthermore, the quantities of compounds 1 and 2 from RLMF were 5.36 and 10.37 mg g -1 , respectively, as determined using HPLC. These compounds were further assessed for acetylcholinesterase inhibitory and neuroprotection properties. The results showed that 1 and 2 showed potent AChE inhibitory activities with IC 50 values of 29.22 and 45.47 μg mL -1 , respectively. At high concentration, compounds 1 and 2 produced a 92% and 89% inhibition on the target enzyme, which was consistent with docking results between AChE and each isolate. Moreover, both 1 and 2 exhibited potential neuroprotective activities against H 2 O 2 -induced SHSY5Y cell death., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Rosa laevigata fruit has been known as a functional foodstuff for a long time. Recently, increasing attention has been given to polysaccharides from R. laevigata fruit due to their numerous medicinal and nutritional properties. In this study, a rapid and effective approach for the extraction and separation of polysaccharides from the title fruit was developed using microwave-assisted aqueous two-phase extraction (MA-ATPE) with a PEG/ammonium sulfate system. After analysis of the response surface methodology (RSM) data based on a Box-Behnken design (BBD), a model was proposed and was found to predict an optimum yield value of 258.99 mg g -1 which is in good agreement with the experimental value (258.59 mg g -1 ). Two selenium (Se)-containing polysaccharides, Se-RLFP-1 and Se-RLFP-2, were isolated from R. laevigata fruit. Their chemical structures were elucidated by acid hydrolysis, weight-average molecular mass and Se-content analysis, along with UV, FT-IR, 1 H and 13 C NMR spectroscopy. As a result, Se-RLFP-1 was found to be mainly composed of mannose, glucose, galactose and xylose in a molar ratio of 1.4 : 7.9 : 1.0 : 1.5, while Se-RLFP-2 was composed of mannose, rhamnose, glucose, galactose and xylose (12.6 : 1.0 : 38.3 : 5.6 : 19.6). Furthermore, the antioxidant properties of the polysaccharides were investigated on the basis of FRAP, ABTS and DPPH radical scavenging assays. The results showed that the two polysaccharides had a noticeable effect on the radical scavenging of ABTS and DPPH, especially at high concentrations. In addition, the neuroprotective effect of Se-RLFP-1 and Se-RLFP-2 against oxidative stress induced by H 2 O 2 in SH-SY5Y neuroblastoma cells was also investigated. In particular, Se-RLFP-1 exhibited obvious neuroprotective activity at a concentration of 100 μg mL -1 .