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Plant seeds are not merely reproductive organs, they are also carriers of microorganism, particularly, inherent and non-invasive characteristic endophytes in host plant. Therefore, in this study, the endophytic diversity of Angelica seeds was studied and compared with endophytes isolated from healthy leaves, stems, roots, and seeds of A. sinensis using 20 different media. The metabolites of endophytic strains were evaluated with six different methods for their antioxidant activity and the paper disc diffusion method for antimicrobial activities. As a result, 226 endophytes were isolated. Compared with the biodiversity and abundance of uncultured fungi from Angelica seed, the result showed that the most frequent endophytic fungi were Alternaria sp. as seen in artificial media; moreover, compared with artificial media, the pathogenic fungi, including Fusarium sp. and Pseudallescheria sp., were not found from the Angelica seed, the results suggested it may not be inherent endophytes in plants. In addition, bacteria from seven phyla were identified by high-throughput sequencing, while five phyla of endophytic bacteria were not isolated on artificial media including Proteobacteria, Actinobacteria, Bacteroidetes, Microgenomates, and Saccharibacteria. Furthermore, the sample JH-4 mycelium displayed the best antioxidant activity, and the active constituent may be a flavonoid as determined by total phenol and flavonoid content. Moreover, YH-12-1 mycelium had strong inhibitory activity against the five tested strains and the minimum inhibitory concentration (MIC) against Pseudomonas aeruginosa and Streptococcus pneumoniae was found to be 25 μg/mL. Our results confirm that plant endophytes are rich in biodiversity and contain important resource of many uncultured microorganisms.

The fully cored CSDP-2 Well, drilled in the central uplift region of the South Yellow Sea, China, provides indispensable and very significant research opportunities to understand the evolution of life, paleoclimate, paleogeography, and tectonics during the Permian in the South Yellow Sea area of the Yangtze paleoblock. We here analyze 118 samples from 893.7 to 1798.8 m depth of the CSDP-2 borehole core and recognize three Permian palynological assemblages, Laevigatosporites minimus – Florinites florini (MF) for the Kungurian mid-lower Qixia Formation, Crucisaccites quadratoides – Limitisporites rhombicorpus (QR) for the Capitanian lower Longtan Formation and Macrotoispora media – Anticapipollis tornatilis (MT) for the Wuchiapingian upper Longtan Formation, in an ascending order. These palynological assemblages indicate a warm and semi-humid rainforest paleoenvironment and a drying tendency of the paleoclimate. The present study area belongs to the Yangtze paleoblock in paleogeography and is a part of the Cathaysia flora based on mega-plant fossil records. However, our palynological assemblages show similarities to those of both South China and North China subzones and, especially, their pollen contents with arid coniferous affinities highly similar to those in the north part of the South China subzone. The presence of conifers might suggest a more arid climate in the North China subzone had started to affect the Yellow Sea area in the Lopingian (Permian). [ABSTRACT FROM AUTHOR]

Abstract This study focuses on the Mesozoic–Cenozoic tectono-thermal events in the Central Uplift of the South Yellow Sea Basin (SYSB) based on the CSDP-2 borehole. CSDP-2 is the first borehole to penetrate the integrated Paleozoic–Mesozoic sedimentary strata and recovered approximately 2736 m of core. The drilling results confirm a significant stratigraphic hiatus, i.e., Indosinian unconformity, between the Neogene–Quaternary and the underlying Lower Triassic. The eroded thickness estimated from sonic log and vitrinite reflectance data range from ∼1200 to 1400 m. Multiple paleo-thermometer data from the CSDP-2 cores, including vitrinite reflectance, apatite/zircon fission-track (AFT/ZFT) and fluid inclusions, were used to reconstruct the Mesozoic–Cenozoic thermal history in the study area. There was a continuous heating process during the early Mesozoic. The peak paleo-temperature may have reached up to 160 °C (base Permian) during the Late Jurassic, with the highest paleo-geothermal gradient of approximately 58.8 °C·km−1. The tectono-thermal evolution was dominated by the Mesozoic intracontinental collision between the Yangtze Craton and the Sino-Korean platform. The heating process was mainly caused by rapid burial on the passive continental margin and igneous activities. The paleo-temperature significantly decreased following the Late Jurassic. Two rapid cooling processes ca. 100–65 Ma and ca. 35 Ma are suggested by the AFT modeling results. Cooling history indicates that the tectonic uplift and denudation likely occurred from the Early Cretaceous to the Miocene. The reconstruction results of thermal evolution confirm that the Mesozoic–Paleozoic source rocks are mature or even highly mature, and hydrocarbon generation, migration and charge undoubtedly occurred in the Central Uplift, showing substantial hydrocarbon potential. Moreover, the reconstruction of the tectono-thermal history provides important constraints for regional tectonic studies. Highlights • Mesozoic–Cenozoic tectono-thermal events in the Central Uplift of the South Yellow Sea Basin was discussed. • Tectono-thermal history was reconstructed based on multiple paleo-thermometer data from the CSDP-2 borehole. • Substantial hydrocarbon potential in the marine deposits in the SYSB was confirmed. [ABSTRACT FROM AUTHOR]