Nitrogen regulates the synthesis of hydrophobic amino acids to improve protein structural and gel properties in common buckwheat.

Nitrogen (N) fertilizer impacts the grain quality of common buckwheat, but the effects and regulatory mechanisms of N on various protein parameters of buckwheat are not fully understood. The purpose of this study was to investigate the particle morphology, structural and gel properties, and regulation mechanism of buckwheat protein under four N levels. The bulk density, surface hydrophobicity, particle size, and thermal properties of the buckwheat protein were maximized through the optimal N application (180 kg N/ha), further enhancing the thermal stability of the protein. N application increased the ß-sheet content and reduced the random coil content. Appropriate N fertilizer input enhanced the tertiary structure stability and gel elasticity of buckwheat protein by promoting hydrophobic interactions, disulfide bonds, ionic bonds, storage modulus and loss modulus. The differentially expressed proteins induced by N are primarily enriched in small ribosomal subunit and ribosome, improving protein quality mainly by promoting the synthesis of hydrophobic amino acids. Future agriculture should pay attention to the hydrophobic amino acid content of buckwheat to effectively improve protein quality. This study further advances the application of buckwheat protein in the field of food processing and provides a theoretical basis for the extensive development and utilization of buckwheat protein.

Qualitative and quantitative analyses of chemical constituents in vitro and in vivo and systematic evaluation of the pharmacological effects of Tibetan medicine Zhixue Zhentong capsules.

Introduction: Zhixue Zhentong capsules (ZXZTCs) are a Tibetan medicine preparation solely composed of Lamiophlomis rotata (Benth.) Kudo. L. rotata is the only species of the genus Laniophlomis (family Lamiaceae) that has medicinal constituents derived from the grass or root and rhizome. L. rotata is one of the most extensively used folk medicines by Tibetan, Mongolian, Naxi, and other ethnic groups in China and has been listed as a first-class endangered Tibetan medicine. The biological effects of the plant include hemostasis, analgesia, and the removal of blood stasis and swelling. Purpose: This study aimed to profile the overall metabolites of ZXZTCs and those entering the blood. Moreover, the contents of six metabolites were measured and the hemostatic, analgesic, and anti-inflammatory effects of ZXZTCs were explored. Methods: Ultra-performance liquid chromatography-tandem quadrupole time-of-flight high-resolution mass spectrometry (UPLC-Q-TOF-MS) was employed for qualitative analysis of the metabolites of ZXZTCs and those entering the blood. Six metabolites of ZXZTCs were quantitatively determined via high-performance liquid chromatography The hemostatic, analgesic, and anti-inflammatory effects of ZXZTCs were evaluated in various animal models. Results: A total of 36 metabolites of ZXZTCs were identified, including 13 iridoid glycosides, 9 flavonoids, 9 phenylethanol glycosides, 4 phenylpropanoids, and 1 other metabolite. Overall, 11 metabolites of ZXZTCs entered the blood of normal rats. Quantitative analysis of the six main metabolites, shanzhiside methyl ester, chlorogenic acid, 8-O-acetyl shanzhiside methyl ester, forsythin B, luteoloside, and verbascoside, was extensively performed. ZXZTCs exerted hemostatic effects by reducing platelet aggregation and thrombosis and shortening bleeding time. Additionally, ZXZTCs clearly had an analgesic effect, as observed through the prolongation of the latency of writhing, reduction in writhing, and increase in the pain threshold of experimental rats. Furthermore, significant anti-inflammatory effects of ZXZTCs were observed, including a reduction in capillary permeability, the inhibition of foot swelling, and a reduction in the proliferation of granulation tissue. Conclusion: Speculative identification of the overall metabolites of ZXZTCs and those entering the blood can provide a foundation for determining its biologically active constituents. The established method is simple and reproducible and can help improve the quality control level of ZXZTCs as a medicinal product. Evaluating the hemostatic, analgesic, and anti-inflammatory activities of ZXZTCs can help reveal its mechanism.

Pseudoephedrine and its derivatives antagonize wild and mutated severe acute respiratory syndrome-CoV-2 viruses through blocking virus invasion and antiinflammatory effect.

The coronavirus disease 2019 has infected over 150 million people worldwide and led to over 3 million deaths. Severe acute respiratory syndrome (SARS)-CoV-2 lineages B.1.1.7, B.1.617, B.1.351, and P.1 were reported to have higher infection rates than that of wild one. These mutations were noticed to happen in the receptor-binding domain of spike protein (S-RBD), especially mutations N501Y, E484Q, E484K, K417N, K417T, and L452R. Currently, there is still no specific medicine against the virus; moreover, cytokine storm is also a dangerous factor for severe infected patients. In this study, potential S-RBD-targeted active monomers from traditional Chinese medicine Ephedra sinica Stapf (ephedra) were discovered by virtual screening. NanoBiT assay was performed to confirm blocking activities of the screened compounds against the interaction between SARS-CoV-2 S-RBD and angiotensin-converting enzyme 2 (ACE2). We further analyzed the blocking effect of the active compounds on the interactions of mutated S-RBD and ACE2 by computational studies. Moreover, antiinflammatory activities were evaluated using qRT-PCR, enzyme-linked immune sorbent assay, and Western blot analysis. As a result, pseudoephedrine (MHJ-17) and its derivative (MHJ-11) were found as efficient inhibitors disrupting the interactions between ACE2 and both wild and mutated S-RBDs. In addition, they also have antiinflammatory activities, which can be potential drug candidates or lead compounds for further study.

Optimization of a novel single air-lift sequencing bioreactor for raw piggery wastewater treatment: Nutrients removal and microbial community structure analysis.

In this study, a sequencing batch and intermittent air-lift bioreactor (SBIAB) was evaluated under the three independent variables to treat raw piggery wastewater. The effects of hydraulic retention time (HRT), air flow rate and sludge retention time (SRT) on the nutrients removal of SBIAB were researched. The optimum values of HRT, air flow rate and SRT were 8 d, 2 l/min and 20 d, respectively. Meanwhile, the removal rates of chemical oxygen demand (COD), NH4+-N, total nitrogen (TN) and total phosphorus (TP) were up to 89.5%, 93.5%, 61.1% and 57.3%, respectively. Generally, the nutrients removal performance could be enhanced with increasing HRT from 6 to 10 d, while it was inhibited at air flow rate of 3 l/min. Higher air flow rate caused the alkaline pH and high free ammonia concentration, which imposed restrictions on the process of wastewater treatment. In the SBIAB, a coupling of aerobic/anoxic/anaerobic zone was formed according to the changes of oxidation-reduction potential (ORP) values at the optimum condition. Microbial community structure analysis indicated that the functional microbes including Brachymonas, Prokaryote, Giesbergeria, Comamonadaceae bacterium, Clostridiales bacterium, Comamonas, Tissierella, Aequorivita were enriched in the SBIAB, which played a significant role in the removal of complex organics and nitrogen.

Glycyrrhizic acid exerts inhibitory activity against the spike protein of SARS-CoV-2.

Coronavirus causes a disease with high infectivity and pathogenicity, especially SARS in 2003, MERS in 2012, and COVID-2019 currently. The spike proteins of these coronaviruses are critical for host cell entry by receptors. Thus, searching for broad-spectrum anti-coronavirus candidates, such as spike protein inhibitors, is vital and desirable due to the mutations in the spike protein. In this study, a combination of computer-aided drug design and biological verification was used to discover active monomers from traditional Chinese medicine. Surface plasmon resonance (SPR) assays and NanoBit assays were used to verify the predicated compounds with their binding activities to spike proteins and inhibitory activities on the SARS-CoV-2 RBD/ACE2 interaction, respectively. Furthermore, an MTT assay was used to evaluate the cell toxicities of active compounds. As a result, glycyrrhizic acid (ZZY-44) was found to be the most efficient and nontoxic broad-spectrum anti-coronavirus molecule in vitro, especially, the significant effect on SARS-CoV-2, which provided a theoretical basis for the study of the pharmacodynamic material basis of traditional Chinese medicine against SARS-CoV-2 and offered a lead compound for further structural modification in order to obtain more effective candidate drugs against SARS-CoV-2.

Polygonum perfoliatum L., an Excellent Herbal Medicine Widely Used in China: A Review.

Polygonum perfoliatum L. (synonym: Polygonum knotweed L.; Persicaria perfoliata; family: Polygonaceae) is a kind of folk traditional Chinese medicine with a long history of wide use in the treatment of ancient internal, surgical, and gynecological diseases. At present, 80 chemical constituents have been isolated from P. perfoliatum, including flavonoids, anthraquinones, terpenoids, phenolic acids, phenylpropanoids, and alkaloids, among which flavonoids are the main active components. Modern studies have shown that P. perfoliatum has pharmacological activities such as anti-inflammatory, anti-bacterial, antiviral, anti-liver fibrosis, antitussive and expectorant, anti-tumor, anti-oxidation, and so on. By consulting and sorting out a large number of related literatures at home and abroad in recent years, this paper systematically reviewed the botany, traditional uses, phytochemistry, pharmacological activities, and quality control of P. perfoliatum, and discussed its development potential in new drug research and clinical application in the future, in order to provide a reference basis for further research and promote the in-depth development and utilization.

Novel probiotic-bound oxidized Bletilla striata polysaccharide-chitosan composite hydrogel.

As a new strategy for wound management, probiotics are highly sensitive to the external environment during use. In this study, an attempt is made to apply oxidized Bletilla striata polysaccharide (OBSP) hydrogel as a delivery system to put up a physical barrier to probiotics. Bletilla striata, as a famous traditional Chinese medicine, has been widely used for over 1500 years to promote wound healing. Firstly, probiotic-bound OBSP-Chitosan composite hydrogel (OBSP-CS-LP hydrogel) was prepared by a simple and environmentally friendly approach. Subsequently, the SEM image, swelling and rheological properties of the OBSP-CS-LP hydrogel were investigated. Notably, composite probiotics to wounds are an attractive novel intervention that significantly improves the antibacterial properties of the hydrogel and avoids the pitfalls of many antibiotic therapies. Furthermore, the full-thickness skin defect model in vivo indicated an outstanding wound healing efficacy. Therefore, OBSP-CS-LP hydrogel could be applied as a promising dressing in the wound healing.

Investigation of 6-O-methyl-scutellarein metabolites in rats by ultra-flow liquid chromatography/quadrupole-time-of-flight mass spectrometry.

Context Scutellarin (1) has been widely used in China to treat acute cerebral infarction and paralysis induced by cerebrovascular diseases. However, scutellarin (1) has unstable metabolic characteristics. Objective The metabolic profile of 6-O-scutellarein was studied to determine its metabolic stability in vivo. Materials and methods In this study, a method of UFLC/Q-TOF MS was used to study the 6-O-methyl-scutellarein metabolites in rat plasma, urine, bile and faeces after oral administration of 6-O-methyl-scutellarein (3). One hour after oral administration of 6-O-methyl-scutellarein (3) (34 mg/kg), approximately 1 mL blood samples were collected in EP tubes from all groups. Bile, urine and faeces samples were collected from eight SD rats during 0-24 h after oral administration. The mass defect filtering, dynamic background subtraction and information dependent acquisition techniques were also used to identify the 6-O-methyl-scutellarein metabolites. Results The parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces. The glucuronide conjugate of 6-O-methyl-scutellarein (M1, M2), diglucuronide conjugate of 6-O-methyl-scutellarein (M3), sulphate conjugate of 6-O-methyl-scutellarein (M4), glucuronide and sulphate conjugate of 6-O-methyl-scutellarein (M5), methylated conjugate of 6-O-methyl-scutellarein (M6) were detected in rat urine. M1, M2 and M3 were detected in rat bile. M1 was found in rat plasma and M7 was detected in faeces. Discussion and conclusion Because the parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces, we speculate that 6-O-methyl-scutellarein (3) had good metabolic stability in vivo. This warrants further study to develop it as a promising candidate for the treatment of ischemic cerebrovascular disease.