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The central Inner Mongolia, located at the intersection of the northern margin of the North China Craton (NCC) and the Central Asian Orogenic Belt, is crucial for deciphering the Late Palaeozoic tectonic evolution associated with the subduction and closure of the Palaeo‐Asian Ocean (PAO). Our study focused on petrology, detrital zircon LA–ICP–MS U–Pb geochronology and whole‐rock geochemistry for the Late Carboniferous to Permian sandstones within the Shuanmazhuang, Dahongshan, Naobaogou, and Laowopu formations in Siziwang Banner, central Inner Mongolia. This comprehensive analysis shed light on the dynamic interplay between the NCC and the South Mongolia Block. Detrital zircon U–Pb ages in investigated samples mainly cluster between 250 and 2650 Ma, with significant peaks at 2.4–2.5 Ga, 1.8–2.0 Ga, 400–430 Ma, and 250–320 Ma, respectively. The geochemistry data are characterized by SiO2 contents (56.29–77.95 wt. %), Na2O / K2O ratios (0.45–1.58) and SiO2/Al2O3 ratios between 4.33 and 7.44. Moreover, they exhibit the slight enrichment in large ion lithophile elements (Rb and Ba) and the depletion in high field strength elements (Nb, Ta, Th, and U). These facts indicate that the sedimentary detritus predominantly originates from felsic sources, probably deriving from the Late Carboniferous–Permian continental island arc‐related intermediate‐acid igneous rocks, the Late Ordovician‐Silurian magmatic rocks in the Bainaimiao arc and the basements of the NCC. Furthermore, our present results also suggest that during the Early–Middle Permian, accelerating oceanic crust subduction triggered significant magmatic events in Siziwang Banner, leading to rapid uplift and the erosion of arc magmatic rocks, as well as the abundant corresponding sediments. Subsequently, the gradual convergence and eventual collision between the NCC and the Southern Mongolian Block took place at the end of the Permian, representing final closure of the PAO. [ABSTRACT FROM AUTHOR]

Dendrobium nobile is a beautiful orchid and a widely used medicinal plant. In vitro antioxidant assays suggested that D. noblie flower extracts showed significantly higher 2, 2′-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging rates and much more ferric-reducing power than those of root, stem, leaf and fruit. To better understand the antioxidant basis of D. nobile flower, high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was used for metabolic identification and quantification. Finally, there were 72 metabolites among the total of 712 identified components showed significant association (coefficient >0.8, p < 0.05) with ABTS scavenging rates, DPPH scavenging rates, and ferric-reducing power. The three enriched classes of flower metabolites, including amino acids and their derivatives, organic acids and their derivatives, and flavonoids, formed the main antioxidant basis. The significantly accumulated rutin, astragalin, isomucronulatol-7-O-glucoside, quercetin 4′-O-glucoside, methylquercetin O-hexoside, caffeic acid, caffeic acid O-glucoside, and p-coumaric acid (Log2(fold change) >2, p < 0.01 , distribution in flower >0.1%) made a key contribution to the higher antioxidant activities in flower. The relative quantification results of HPLC-MS/MS were verified by the common quantification methods. The antioxidant basis revealed of D. nobile flower will be helpful in the production of healthy or beauty products. [ABSTRACT FROM AUTHOR]

Dendrobium liquor obtained by soaking Dendrobium in Chinese liquor is considered as a health drink in China. Here, we found the pretreatment of extract of Dendrobium nobile Lindl. liquor (DNLE) attenuated the oxidative damage to cells caused by H2O2, while the abilities of DNLE of eliminating extracellular free radicals and promoting the activities of intracellular antioxidant enzymes were observed. Quantitative proteomics identified 375 differentially expressed proteins caused by H2O2 treatment in 293T cells. However, only 12 differentially expressed proteins were found in DNLE‐pretreated cells which under the same oxidative damage. This suggested that the pretreatment of DNLE could suppress the disorder of protein expressions caused by oxidative stress which could induce cell death. Besides, DNLE was helpful for avoiding the unfolded protein response (UPR) and cell cycle disorder caused by oxidative stress. Taken together, these results demonstrated that Dendrobium liquor could be a healthy herbal drink with antioxidant function. Practical applications: Dendrobium is used as an edible herb and a tonic food in traditional Chinese medicine. Dendrobium liquor obtained by soaking Dendrobium with Chinese liquor is also regarded as a nourishing health drink. However, there is rare research data on biological activity of Dendrobium liquor. Our current results demonstrated that the extract of Dendrobium nobile Lindl. liquor (DNLE) possessed the ability of eliminating free radicals in/out the human cells. More importantly, DNLE could help cells to resist the interference on cell life activities caused by oxidative stress. Since many evidences suggested that oxidative stress is linked to human disease and aging, and chemical antioxidant has some side effects on health, Dendrobium liquor can serve as a natural health drink with antioxidant function. Furthermore, the active ingredients in DNLE also possess the potential to be developed as natural antioxidant additive in food and cosmetics. [ABSTRACT FROM AUTHOR]