A new flavonol acylglycoside from the fruits of Nitraria tangutorum Bobr

Phytochemical profiles and evaluation of the biological potential of ethyl acetate and n-butanol fractions of the aerial parts of Cistus albidus L

The phytochemical profiles of the ethyl acetate (EAFCA) and n-butanol (BFCA) fractions of the aerial parts of Cistus albidus L., were characterised by a developed LC-ESI-MS/MS method, using 53 fingerprint phytochemicals, revealing the presence of 26 and 22 compounds, respectively with quinic acid, gallic acid, protocatechuic acid, catechin, gentisic acid, tannic acid, ellagic acid, quercitrin, astragalin as the major compounds of the EAFCA, in very higher amounts than in the BFCA. The antioxidant activity was evaluated using six methods (DPPH•, ABTS•+, GOR•, CUPRAC, FRAP and Phenanthroline). In agreement with its highest polyphenolic content (430.12 ± 1.02 µg GAE/mg of extract) and largest amounts of identified polyphenolics, the EAFCA exhibited a higher antioxidant activity than the BFCA. Additionally, the EAFCA showed the highest acetylcholinesterase (AChE) inhibition (IC50 of 25.1 ± 2.58 µg/mL). Moreover, both EAFCA and BFCA demonstrated high photoprotective activity, with sun protection factor (SPF) values of 36.49 and 36.52, respectively.

The Role of Natural and Synthetic Flavonoids in the Prevention of Marine Biofouling

Marine biofouling is a major concern for the maritime industry, environment, and human health. Biocides which are currently used in marine coatings to prevent this phenomenon are toxic to the marine environment, and therefore a search for antifoulants with environmentally safe properties is needed. A large number of scientific papers have been published showing natural and synthetic compounds with potential to prevent the attachment of macro- and microfouling marine organisms on submerged surfaces. Flavonoids are a class of compounds which are highly present in nature, including in marine organisms, and have been found in a wide range of biological activities. Some natural and synthetic flavonoids have been evaluated over the last few years for their potential to prevent the settlement and/or the growth of marine organisms on submerged structures, thereby preventing marine biofouling. This review compiles, for the first-time, natural flavonoids as well as their synthetic analogues with attributed antifouling activity against macrofouling and microfouling marine organisms.

Chemical Profiling of Nitraria roborowskii Kom. by UPLC-Q-Orbitrap-MS and Their Hypolipidemic Effects in Vivo

The Nitraria roborowskii Kom. (NRK) berries, as fruits of the genus Nitraria of the Zygophyllceae family, have been widely used as folk medicine. Modern pharmacological research has demonstrated that Nitraria berries had hypolipidemic, hypoglycemic, and immunomodulatory effects. However, more research needs to be reported on the chemical composition and biological activity of NRK. Hence, the phenolic compounds in the NRK berries were comprehensively analyzed and characterized by Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS) in this study. In total, 52 phenolics were identified, and all were reported for the first time. In addition, the hypolipidemic efficacy of NRK berries extract was studied in the hyperlipidemic mouse model. After treatment, the high dose group of NRK substantially reversed total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels. Through lipidomics technology, 27 potential biomarkers were characterized. And there was a significant callback at 25 of them after NRK treatment by using statistical analysis methods. Pathway analysis results demonstrated that NRK might exert therapeutic effects by regulating glycerophospholipid and glycerolipid metabolism pathways. This study could provide firsthand information on NRK berries for their phenolic compounds and potential application in preventing and treating hyperlipidemia.

Hypoglycemic effect of Nitraria tangutorum fruit by inhibiting glycosidase and regulating IRS1/PI3K/AKT signalling pathway and its active ingredient identification by UPLC-MS

The hypoglycemic effect of NTB-40 (40% ethanol fraction of Nitraria tangutorum fruit) in type I/II diabetic mice and its underlying mechanism and active ingredient structure were investigated. The postprandial blood glucose (PBG) lowering effect of NTB-40 treatment was confirmed by maltose, starch, and sucrose tolerance tests in alloxan-induced DM mice and sucrase and maltase inhibitory activities in vitro. More importantly, long-term dosing experiments in high-fat diet-STZ-induced diabetic mice further demonstrated that NTB-40 intervention could improve glycolipid metabolism disorder and insulin resistance (IR) by maintaining glucose homeostasis (FBG, OGTT, ITT, FINS, and HOMA-IR) and lipid homeostasis (TC, TG, HDL-C, LDL-C, and FFA), reducing inflammation (IL-6, IL-1β, and TNF-α) and oxidative stress (SOD and MDA), ameliorating the liver's histological structural abnormalities, and modulating the IRS1/PI3K/AKT signaling pathway and downstream targets (FOXO1, GSK3β, GLUT4) for decreasing hepatic gluconeogenesis and promoting glycogen synthesis and glucose uptake. All these results indicated that NTB-40 had an anti-diabetic effect by modulating the IRS1/PI3K/AKT signaling pathway and inhibiting α-glucosidase activity. Finally, the main chemical components of NTB-40, including phenolic acids, flavonoids, and alkaloids, were assigned by UPLC-Triple-TOF MS/MS.

Contrasting Regulators of the Onset and End of the Seed Release Phenology of a Temperate Desert Shrub Nitraria tangutorum

Seed release is crucial in the reproductive cycle of many desert plant species, but their responses to precipitation changes are still unclear. To clarify the response patterns, we conducted a long-term in situ water addition experiment with five treatments, including natural precipitation (control) plus an extra 25%, 50%, 75%, and 100% of the local mean annual precipitation (145 mm), in a temperate desert in northwestern China. Both the onset and end of the seed release phenophase of the locally dominant shrub, Nitraria tangutorum, were observed from 2012 to 2018. The results showed that both the onset and end time of seed release, especially the end time, were significantly affected by water addition treatment. On average, the end time of seed release was advanced by 3.9 d, 7.3 d, 10.8 d, and 3.8 d under +25%, +50%, +75%, and +100% water addition treatments, respectively, over the seven-year study, compared with the control. The changes in the onset time were relatively small (only several hours), and the duration of seed release was shortened by 4.0 d, 7.5 d, 10.8 d, and 2.0 d under +25%, +50%, +75%, and +100% water addition treatments, respectively. The onset and end time of seed release varied greatly between the years. Preceding fruit ripening and summer temperature jointly regulated the inter-annual variation of the onset time of seed release, while the cumulative summer precipitation played a key role in driving the inter-annual variation of the end time. The annual mean temperature controlled the inter-annual variation of the seed release duration, and these interactions were all non-linear.

Alkaloids and phenolics identification in fruit of Nitraria tangutorum Bobr. by UPLC-Q-TOF-MS/MS and their a-glucosidase inhibitory effects in vivo and in vitro

Nitraria tangutorum Bobr. (NTB), mainly distributed in the Qaidam Basin of Tibetan Plateau, have high economic, ecological and medicinal value. The chemical compositions in the NTB fruits were tentatively analyzed and characterized by applying UPLC-Q-TOF-MS/MS. Total 45 constituents, including 9 hydroxycinnamic acids derivatives, 12 flavonols, 4 flavonoids, 1 trolox derivative, 8 β-carboline alkaloids, 4 tryptophan derivatives, and 7 other amino acid derivatives were identified by comparing with standard products, and analyzing their retention times, characteristic fragment ions and deprotonated molecule ions. The activity studies in vitro indicated that NTB-Z and NTB-C extracts had marked inhibitory effects against sucrase and maltase. Further sucrose/maltose/starch tolerance experiment demonstrated that both NTB-Z and NTB-C extracts at 400 mg/kg could markedly lower the postprandial blood glucose (PBG) level in diabetic animals. All these results indicated that the NTB fruits could be used as the functional health food or medicine for controlling postprandial blood glucose level.