The plastid-localized lipoamide dehydrogenase 1 is crucial for redox homeostasis, tolerance to arsenic stress and fatty acid biosynthesis in rice.

Soil contamination with arsenic (As) can cause phytotoxicity and reduce crop yield. The mechanisms of As toxicity and tolerance are not fully understood. In this study, we used a forward genetics approach to isolate a rice mutant, ahs1, that exhibits hypersensitivity to both arsenate and arsenite. Through genomic resequencing and complementation tests, we identified OsLPD1 as the causal gene, which encodes a putative lipoamide dehydrogenase. OsLPD1 was expressed in the outer cell layer of roots, root meristem cells, and in the mesophyll and vascular tissues of leaves. Subcellular localization and immunoblot analysis demonstrated that OsLPD1 is localized in the stroma of plastids. In vitro assays showed that OsLPD1 exhibited lipoamide dehydrogenase (LPD) activity, which was strongly inhibited by arsenite, but not by arsenate. The ahs1 and OsLPD1 knockout mutants exhibited significantly reduced NADH/NAD+ and GSH/GSSG ratios, along with increased levels of reactive oxygen species and greater oxidative stress in the roots compared with wild-type (WT) plants under As treatment. Additionally, loss-of-function of OsLPD1 also resulted in decreased fatty acid concentrations in rice grain. Taken together, our finding reveals that OsLPD1 plays an important role for maintaining redox homeostasis, conferring tolerance to arsenic stress, and regulating fatty acid biosynthesis in rice.

Molecular mechanisms underlying the toxicity and detoxification of trace metals and metalloids in plants.

Plants take up a wide range of trace metals/metalloids (hereinafter referred to as trace metals) from the soil, some of which are essential but become toxic at high concentrations (e.g., Cu, Zn, Ni, Co), while others are non-essential and toxic even at relatively low concentrations (e.g., As, Cd, Cr, Pb, and Hg). Soil contamination of trace metals is an increasing problem worldwide due to intensifying human activities. Trace metal contamination can cause toxicity and growth inhibition in plants, as well as accumulation in the edible parts to levels that threatens food safety and human health. Understanding the mechanisms of trace metal toxicity and how plants respond to trace metal stress is important for improving plant growth and food safety in contaminated soils. The accumulation of excess trace metals in plants can cause oxidative stress, genotoxicity, programmed cell death, and disturbance in multiple physiological processes. Plants have evolved various strategies to detoxify trace metals through cell-wall binding, complexation, vacuolar sequestration, efflux, and translocation. Multiple signal transduction pathways and regulatory responses are involved in plants challenged with trace metal stresses. In this review, we discuss the recent progress in understanding the molecular mechanisms involved in trace metal toxicity, detoxification, and regulation, as well as strategies to enhance plant resistance to trace metal stresses and reduce toxic metal accumulation in food crops.

[Research status of Bovis Calculus and relevant Chinese patent medicines based on bibliometric analysis].

With scarce resources, natural Bovis Calculus is expensive and hard to meet clinical demand. At the moment, four kinds of Bovis Calculus are available on the market: the natural product, in vitro cultured product, synthesized product, and the product formed in cow after manual intervention. In this study, papers on the four kinds of Bovis Calculus products and relevant Chinese patent medicines were searched from Web of Science, PubMed, and China National Knowledge Infrastructure(CNKI). CiteSpace, citexs AI, and CNKI were employed for bibliometric analysis and knowledge map analysis. On this basis, the status, trend, and focuses of research on Bovis Calculus and relevant Chinese patent medicines were summarized. The results suggested overall slow development in the research on Bovis Calculus and relevant Chinese patent medicines with three typical growth stages. It is consistent with the development of Bovis Calculus substitutes and the national policy for the development of traditional Chinese medicine. At the moment, the research on Bovis Calculus and relevant Chinese patent medicines has been on the rise. In recent years, there has been an explosion of research on them, particularly the quality control of Bovis Calculus and the Chinese patent medicines, the pharmacological efficacy of Chinese patent medicines, such as Angong Niuhuang Pills, and the comparison of the quality of various Bovis Calculus products. However, there is a paucity of research on the pharmacological efficacy and the mechanism of Bovis Calculus. This medicinal and the relevant Chinese patent medicines have been studied from diverse perspectives and China becomes outstanding in this research field. However, it is still necessary to reveal the chemical composition, pharmacological efficacy, and mechanism through multi-dimensional deep research.

Cadmium Inhibits Lateral Root Emergence in Rice by Disrupting OsPIN-Mediated Auxin Distribution and the Protective Effect of OsHMA3.

Cadmium (Cd) strongly inhibits root growth, especially the formation of lateral roots (LRs). The mechanism of Cd inhibition on LR formation in rice (Oryza sativa) remains unclear. In this study, we found that LR emergence in rice was inhibited significantly by 1 �M Cd and almost completely arrested by 5 �M Cd. Cd suppressed both the formation and subsequent development of the lateral root primordium (LRP). By using transgenic rice expressing the auxin response reporters DR5::GUS and DR5rev::VENUS, we found that Cd markedly reduced the auxin levels in the stele and LRP. Cd rapidly downregulated the expression of the auxin efflux transporter genes OsPIN1b, OsPIN1c and OsPIN9 in the stele and LRP. The emergence of LRs in a rice cultivar with a null allele of OsHMA3 (Heavy Metal ATPase 3) was more sensitive to Cd than cultivars with functional alleles. Overexpression of functional OsHMA3 in rice greatly alleviated the inhibitory effect of Cd, but the protective effect of OsHMA3 was abolished by the auxin polar transport inhibitor 1-N-naphthylphthalamic acid. The results suggest that Cd inhibits LR development in rice by disrupting OsPIN-mediated auxin distribution to LRP and OsHMA3 protects against Cd toxicity by sequestering Cd into the vacuoles.

[Analysis of water-soluble nutrients in Lycium barbarum leaves and differences between different producing areas].

This study is to clarify the composition and content differences of water-soluble nutrients in Lycium barbarum leaves(LBLs) from different areas. The total polysaccharides, free monosaccharides and oligosaccharides, nucleosides and amino acids in 35 batches of LBLs were analyzed with use of spectrophotometry, HPLC-ELSD and UPLC-MS/MS. The results showed that LBLs contained abundant polysaccharides, fructose, glucose, sucrose and maltose, with an average contents of 39.07, 12.69, 8.99, 17.44, 8.32 mg·g~(-1), respectively. Besides, eight nucleosides and twelve amino acids were detected in LBLs, and their average total contents were 54.95, 336.9 µg·g~(-1). Principal component analysis(PCA) and partial least squares discrimination analysis(PLS-DA) of carbohydrate, nucleoside and amino acid showed that the water-soluble nutrients of the samples from Qinghai Province were significantly different from those from other areas mainly in asparagine, proline, glutamine, sucrose, adenine and guanosine. In this study, the compositions and contents of water-soluble nutrients in LBLs were preliminarily clarified, which provided basis for further development and utilization of LBLs resoures.

Analysis of phenolic acids and flavonoids in leaves of Lycium barbarum from different habitats by ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry.

The leaves of Lycium barbarum (LLB) have been utilized as crude drugs and functional tea for human health in China and Southeast Asia for thousands of years. To control its quality, a rapid and sensitive ultra-high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry method was established and validated for the first time for simultaneous determination of 10 phenolic acids and flavonoids (including neochlorogenic acid, protocatechuic aldehyde, p-hydroxybenzoic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, rutin and kaempferol-3-O-rutinoside) in LLB. The separation was performed on an Acquity UPLC C18 chromatographic column (100 × 2.1 mm internal diameter, 1.7 µm particle size) with 0.1% formic acid in water (A)-acetonitrile (B) as the mobile phase under gradient elution. Multiple reaction monitoring mode was adopted to simultaneously monitor the target components. The developed method was fully validated in terms of linearity (r2  ≥ 0.9860), precision (RSD ≤ 6.58%), repeatability (RSD ≤ 6.60%), stability (RSD ≤ 6.17%), recovery (95.56-108.06%, RSD ≤ 4.64%) and limit of detection (0.021-0.664 ng/mL) and limit of quantitation (0.069-2.210 ng/mL), and then successfully applied to evaluate the quality of 64 batches of LLB collected from 41 producing areas in four different provinces of China. The results showed that the LLB, especially collected from Inner Mongolia regions, were rich in the phenolic acids and flavonoids. Rutin, kaempferol-3-O-rutinoside and chlorogenic acid are the predominant compounds contained in LLB. The above findings will provide helpful information for the effective utilization of LLB.

Flowers of Astragalus membranaceus var. mongholicus as a Novel High Potential By-Product: Phytochemical Characterization and Antioxidant Activity.

The root of Astragalus membranaceus var. mongholicus is one of the most popular herbal medicines worldwide. In order to increase the yield of underground roots of A. membranaceus var. mongholicus, its flowers (AMF) have often been removed in their flowering stage, which produces the flowers as waste being discarded. To explore its phytochemicals and potential value for utilization, the antioxidant activities of extracts from AMF were evaluated by a free radical scavenging assay and reducing power assay. The total phenols and flavonoids, as well as the individual compounds, in different extracts of AMF were also investigated. The results showed that the extract ME obtained from AMF through macroporous resins separation exhibited strong antioxidant activities, which were close to those of positive control BHT. ME was rich in phenolic acids and flavonoids, and the contents reached 108.42 mg gallic acid equivalents/g and 265.70 mg rutin equivalents/g, respectively. A total of 31 compounds, including four phenolic acids, nineteen flavonoids, three isoflavones, two pterocarpans, and three saponins, were identified using UPLC-QTOF-MS in ME. Quantitative analysis of sixteen components in the extracts of AMF showed that flavonoids were the predominant constituents, especially for the compounds of hyperoside, rutin, and isorhamnetin-3-O-ß-d-glucoside.

Comparison of Functional Components and Antioxidant Activity of Lycium barbarum L. Fruits from Different Regions in China.

The fruit of Lycium barbarum L. (FLB) has been used as medicines and functional foods for more than 2000 years in East Asia. In this study, carotenoid, phenolic, flavonoid, and polysaccharide contents as well as the antioxidant activities of FLB from 13 different regions in China from a total of 78 samples were analyzed. The results showed that total carotenoid contents ranged from 12.93 to 25.35 mg ß-carotene equivalents/g DW. Zeaxanthin dipalmitate was the predominant carotenoid (4.260-10.07 mg/g DW) in FLB. The total phenolic, total flavonoid, and total polysaccharide contents ranged from 6.899 to 8.253 mg gallic acid equivalents/g DW, 3.177 to 6.144 mg rutin equivalents/g DW, and 23.62 to 42.45 mg/g DW, respectively. Rutin content ranged from 0.1812 to 0.4391 mg/g DW, and ferulic acid content ranged from 0.0994 to 0.1726 mg/g DW. All of these FLB could be divided into two clusters with PCA analysis, and both individual carotenoids and total carotenoid contents could be used as markers for regional characterization. The phenolic components were the main substance for the antioxidant activity of FLB. Considering the functional component and antioxidant activities, FLB produced in Guyuan of Ningxia was the closest to Daodi herbs (Zhongwei of Ningxia), which is commercially available high quality FLB. The results of this study could provide guidance for comprehensive applications of FLB production in different regions.

Evaluation of 24-Hour Ambulatory Blood Pressure Monitoring in Patients with Chronic Kidney Disease with Normal Casual Blood Pressure.

This study evaluated 24-hour ambulatory blood pressure (ABP) monitoring in patients with chronic kidney disease (CKD) who had a normal casual blood pressure (CBP) of less than 140/90 mmHg. A total of 350 patients with CKD (Stages 1-5) and a normal CBP were included, and 24-hour ABPs were monitored. Of these patients, 147 patients (42.0%) exhibited increased mean ABP; 69 patients (19.7%) exhibited masked hypertension; 199 patients (56.9%) exhibited an abnormal BP mode (circadian rhythm disappearing); and 204 patients (58.3%) exhibited increased BP load. The 24-hour ABP and mean day and night BPs in patients with higher CBP were significantly higher than those in patients with normal CBP and healthy controls (P<0.01). Results indicate that abnormal BPs exist in patients with CKD who exhibit normal CBPs.

[Network pharmacology of flavonoids in Sophora alopecuroides].

The aim of this paper was to investigate the potential pharmacological effect of flavonoids in Sophora alopecuroides by network pharmacology. This study predicted the potential targets of 11 flavonoids of S. alopecuroides with help of reversed pharmacophore matching target recognition service platform (PharmMapper). The pathway information was acquired from DAVID and KEGG databases. Cytoscape software was used to construct the "ingredient-target-pathway" network of flavonoids active components of S. alopecuroides. The flavonoids active components of S. alopecuroides play anti-inflammatory, blood sugar regulating and other pharmacological effects by regulating 62 targets (such as INSR，KDR，MET) and intervening 44 pathways, such as B cell receptor signaling pathway, insulin signaling pathway, neurotrophin signaling pathway, and T cell receptor signaling pathway. In this study, the mechanism of "muti components-multitargets-multiple pathway" of flavonoids was studied. It reflects the multi-components, multi-targets and multiple pathway features of traditional Chinese medicine. Meanwhile, it provides a scientific basis for the elucidation the mechanism of S. alopecuroides as a medicine, and the development and utilization resources of S. alopecuroides.

[Research on network pharmacology of alkaloids in Sophora alopecuroides].

It was aimed at exploring the potential pharmacological effects of alkaloids in Sophora alopecuroides by means of network pharmacology in this study. The main alkaloids in S. alopecuroides were collected for analysis of drug properties, prediction of potential targets and screening of signaling pathways. DAVID analysis tool combined with KEGG database was used to annotate and analyze the signaling pathway. The alkaloids-targets-signaling pathways network was built through Cytoscape software. Results showed that 17 alkaloids in S. alopecuroides involved 49 targets (170 times in all) and 22 important signaling pathways. Three nodes in model of network pharmacology were cross-linked, and the metabolic pathways were coordinated and regulated by each other. It indicated that alkaloids in S. alopecuroides may have therapeutic effect on diseases of cancer, metabolic disorder, endocrine system, digestive system, nervous system and so on.

High Efficiency Conversion of Regenerated Cellulose Hydrogel Directly to Functionalized Cellulose Nanoparticles.

This article provides a novel and efficient method of "self-assembly/modification/dispersion" for the preparation of functionalized cellulose nanoparticles (CNPs) based on regenerated cellulose hydrogel (RCH). The process of the preparation of CNPs is simplified greatly, which contributes to broadening the utilization of CNPs. Under the given conditions, cellulose chains self-assemble into nanoparticles, which connect with each other to form strings and walls of nanoparticles inside RCH. Then, RCH acts as the hydrophilic precursor of the preparation of CNPs and is modified by oligo side chains to obtain functionalized RCH with imperfect cellulose II structures. After dispersing the functionalized RCH in dimethyl sulfoxide, individual CNPs are finally isolated from functionalized RCH as a result of the decline of the crystallinity of CNPs. Obtained CNPs possess uniform size and good thermal stability, and also exhibit excellent dispersibility in organic solvents. The particle size of CNPs can be adjusted easily by oligo content and particle size of the self-assembled cellulose nanoparticles in RCH. Prepared CNPs are promising candidates for polymer modification in terms of fillers, and for biomedical fields with respect to drug delivery.

Effects of low-temperature pretreatment on enhancing properties of refuse-derived fuel via microwave irradiation.

The present study focuses on pretreatment of enhancing the properties of refuse-derived fuel (RDF) via low-temperature microwave irradiation. These improved properties include lower chlorine content, a more porous surface structure and better combustion characteristics. In this study, low-temperature microwave irradiation was carried out in a modified microwave apparatus and the range of temperature was set to be 220-300℃. We found that the microwave absorbability of RDF was enhanced after being partly carbonized. Moreover, with the increasing of the final temperature, the organochlorine removal ratio was greatly increased to 80% and the content of chlorine was dramatically decreased to an extremely low level. It was also interesting to find that the chlorine of RDF was mainly released as HCl rather than organic chloride volatiles. The finding is just the same as the polyvinyl chloride pyrolysis process. In addition, pores and channels emerged during the modifying operation and the modified RDF has better combustibility and combustion stability than traditional RDF. This work revealed that low-temperature modification of RDF via microwave irradiation is significant for enhancing the quality of RDF and avoiding HCl erosion of equipment substantially.

[Effects of different drying methods on content of bioactive component and antioxidant activity in Lycium ruthenicum].

To compare the appearances, tastes, contents of bioactive components and antioxidant activity of Lyceum ruthenicum under different drying methods, so as to direct its production practice. The folin-phenol colorimetric method, UV, extinction coefficient method and DPPH, as well as fluorescence recovery after photobleaching (FRAP) method to determine the contents of polyphenols, proanthocyanidins, total anthocyanin and antioxidant activity under different drying methods： vacuum freeze drying, low-temperature oven drying and air drying for L. ruthenicum. The results showed that the drying methods had certain effects on its appearances, tastes, contents of bioactive components and antioxidant activity. The appearances and tastes were best after the L. ruthenicum was dried by vacuum freeze drying, with significantly lower moisture than air drying method. The contents of total polyphenols, anthocyanin and proanthocyanidins were highest by air-drying but lowest by low temperature oven drying in L. ruthenicum. The scavenging ability to DPPH was strongest by freeze-drying and lowest by low temperature oven drying, while the antioxidant activity was strongest by air-drying in the FRAT method. In addition, the appearances and tastes were poor in air drying, with higher moisture but highest contents of the three bioactive components. Therefore, the drying methods for L. ruthenicum shall be comprehensively considered.

[Comparative identification studies on wild and cultivated Glycyrrhiza uralensis produced Ningxia based on index components and near-infrared spectroscopy].

This study is to construct a rapid and effective method for identification of wild and cultivated Glycyrrhiza uralensis (hereinafter referred to as Glycyrrhizae Radix et Rhizoma) from Ningxia by comparison of the difference in chromatography identification based on index components and near-infrared spectroscopy identification. HPLC and UV methods were used to determine the content of liquiritin, glycyrrhizate and total flavonoids for 9 wild Glycyrrhizae Radix et Rhizoma and 14 cultivated Glycyrrhizae Radix et Rhizoma samples,and the near-infrared spectroscopy was also,collected. The results illustrated that the chromatography identification based on index components could not identify wild and cultivated Glycyrrhizae Radix et Rhizoma from Ningxia, while near-infrared spectroscopy could quickly and effectively achieve it. It provides an effective method for the growth pattern identification and application of Glycyrrhizae Radix et Rhizoma.

[Comparative studies on HPLC fingerprint and near-infrared spectra of cultivated and reference crude Scutellaria baicalensis].

Scutellaria baicalensis is a common and important medicinal plant in China, facing with reducing sharply in wild resources. To meet the needs in Chinese herbwouls medicine market and clinical application, S. baicalensis has been widely cultivated in Ningxia, Hebei, Shanxi, and Gansu et al. HPLC finger-print and near-infrared were studied in the research to evaluate quality difference of S. baicalensis in four districts. The results showed that the similarity of HPLC finger-print of 12 cultivated S. baicalensis and reference crude herb is more than 0.961, and the other is more than 0.983. On the other hand, paired sample t-test indicated there has no significant difference between the common peaks' area of 12 cultivated S. baicalensis and reference crude herb. It was verified that 12 cultivated S. baicalensis has highly consistency with reference crude herb. On the basis of chromatographic finger-print and near-infrared spectrum, the study applied paired sample t-test to verify analysis results, which could avoid erroneous judgment induced by indefinite threshold values in the similarity of chromatographic finger-print and provide reliable basis for the analysis results. Meanwhile, it also provides a new idea for improving the quality control method of Chinese medicinal materials by comparative study about two comprehensive detection means.

[Production regionalization study of Glycyrrhiza uralensis].

The distribution information of Glycyrrhiza uralensis was collected by interview investigation and field survey, and 46 related environmental factors were collected, some kinds of functional chemical constituents of G.uralensis were analyzed. Integrated climate, topography and other related ecological factors, the habitat suitability study was conducted based on Arc geographic information system(ArcGIS),and maximum entropy model. The AUC of ROC curve was both above 0.95, indicating that the predictive results with the maximum model were highly precise. The results showed that 5 major ecological factors have obvious influence on ecology suitability distributions of G. uralensis, including July average temperature, soil sub category, Dec precipitation, vegetation types and standard deviation of seasonal variation in temperature, et al. It is suitable for the living habits of the G. uralensis, adequate light, low rainfall, summer heat and large temperature difference between day and night, which is suitable for distribution in the northern temperate plains and mountains. In addition, the ecological suitability regionalization based on the chemical constituents of G.uralensis also provides a new suitable distribution area other than the traditional distribution area, which provides a scientific basis for the reasonable introduction of G.uralensis.

[Production regionalization study of Lycii Fructus].

The distribution information of Lycii Fructus was collected by interview investigation and field survey, and 46 related environmental factors were collected, some kinds of functional chemical constituents the of Lycii Fructus were analyzed. Integrated climate, topography and other related ecological factors, the habitat suitability study was conducted based on Arc geographic information system(ArcGIS),and maximum entropy model. The AUC of ROC curve was both above 0.95, indicating that the predictive results with the maximum model were highly precise. The results showed that 5 major ecological factors had obvious influence on ecology suitability distributions of Lycii Fructus, including soil pH, soil subclass, vegetation type and in August the average temperature et al. It is suitable for the living habits of the Lycii Fructus, dry, cool weather, more hardy, drought-resistant, alkali soil, which is suitable for distribution in the northern temperate plains. In addition, the ecological suitability regionalization based on the chemical constituents of Lycii Fructus also provides a new suitable distribution area other than the traditional distribution area, which provides a scientific basis for the reasonable introduction of Lycii Fructus.

Antibacterial Activity of Plants in Cirsium: A Comprehensive Review.

As ethnic medicine, the whole grass of plants in Cirsium was used as antimicrobial. This review focuses on the antimicrobial activity of plants in Cirsium, including antimicrobial components, against different types of microbes and bacteriostatic mechanism. The results showed that the main antimicrobial activity components in Cirsium plants were flavonoids, triterpenoids and phenolic acids, and the antimicrobial ability varied according to the species and the content of chemicals. Among them, phenolic acids showed a strong antibacterial ability against Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterococcus faecium. The antibacterial mechanisms include: (1) damaging the cell membrane, cell walls, mitochondria and nucleus of bacteria; (2) inhibiting the synthesis of proteins and nucleic acids; (3) suppressing the synthesis of enzymes for tricarboxylic acid cycle pathways and glycolysis, and then killing the bacteria via inhibition of energy production. Totally, most research results on antimicrobial activity of Cirsium plants are reported based on in vitro assays. The evidence from clinical data and comprehensive evaluation are needed.

Rice roots avoid asymmetric heavy metal and salinity stress via an RBOH-ROS-auxin signaling cascade.

Root developmental plasticity is crucial for plants to adapt to a changing soil environment, where nutrients and abiotic stress factors are distributed heterogeneously. How plant roots sense and avoid heterogeneous abiotic stress in soil remains unclear. Here, we show that, in response to asymmetric stress of heavy metals (cadmium, copper, or lead) and salt, rice roots rapidly proliferate lateral roots (LRs) in the stress-free area, thereby remodeling root architecture to avoid localized stress. Imaging and quantitative analyses of reactive oxygen species (ROS) showed that asymmetric stress induces a ROS burst in the tips of the exposed roots and simultaneously triggers rapid systemic ROS signaling to the unexposed roots. Addition of a ROS scavenger to either the stressed or stress-free area abolished systemic ROS signaling and LR proliferation induced by asymmetric stress. Asymmetric stress also enhanced cytosolic calcium (Ca2+) signaling; blocking Ca2+signaling inhibited systemic ROS propagation and LR branching in the stress-free area. We identified two plasma-membrane-localized respiratory burst oxidase homologs, OsRBOHA and OsRBOHI, as key players in systemic ROS signaling under asymmetric stress. Expression of OsRBOHA and OsRBOHI in roots was upregulated by Cd stress, and knockout of either gene reduced systemic ROS signaling and LR proliferation under asymmetric stress. Furthermore, we demonstrated that auxin signaling and cell wall remodeling act downstream of the systemic ROS signaling to promote LR development. Collectively, our study reveals an RBOH-ROS-auxin signaling cascade that enables rice roots to avoid localized stress of heavy metals and salt and provides new insight into root system plasticity in heterogenous soil.