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采用HPLC法测定刺芪参胶囊中人参皂苷含量,采用UV法测定刺芪参胶囊中多糖含量,利用大、小鼠经口急性毒性试验、Ames试验、小鼠骨髓细胞微核试验、小鼠精子畸形试验对刺芪参胶囊的安全性进行评价,采用30d喂养试验进行毒理学研究。结果表明:刺芪参胶囊中人参皂苷及多糖的平均含量分别为0.273,3.190g/100g;刺芪参胶囊对大、小鼠急性经口最大耐受剂量均24.0g/kg·BW,按急性毒性分级,属无毒级;遗传毒性试验均为阴性;30d喂养试验表明,刺芪参胶囊对大鼠的临床检查、血液学指标检查、血生化指标检查、脏器重量和系数以及病理组织学检查等指标均无明显不良影响。说明刺芪参胶囊是一种安全无毒的产品,具有良好的食用安全性。 相似文献
3.
Yang Liu Mingjin Cai Wangyou Zhang Wanling Feng Xingyuan Sun Yang Zhang Hongli Zhou 《International Journal of Food Science & Technology》2021,56(5):2375-2383
In this paper, apple crispness was evaluated by sensory evaluation and compared with non-destructive measurements of portable acoustic signal to discuss the feasibility of non-destructive evaluation for apple crispness based on portable acoustic signal. Acoustic eigenvalues from the acoustic signal were processed by time domain and Hilbert–Huang transform (HHT), followed by analysing the correlations with apple crispness that had been evaluated via sensory evaluation. Multiple linear regression (MLR) and artificial neural network (ANN) were applied to predict apple crispness. The results proved that crispness correlates significantly (P < 0.01) with four acoustic eigenvalues, including waveform index, sound intensity, energy of low frequency and energy of high frequency. The average relative error of apple crispness predicted by ANN was 1.42 ± 1.9%, remarkably lower (P < 0.01) that of MLR (6.79 ± 5.64%), implying that the model predicted by ANN is more accurate than that of MLR. 相似文献
4.
Yuhuan Sun Hongshuang Qin Zhengqing Yan Chuanqi Zhao Jinsong Ren Xiaogang Qu 《Advanced functional materials》2019,29(14)
Recently, quorum sensing (QS) inhibitors (QSIs) have been combined with antibiotics to enhance antibiofilm efficacy in vitro and in vivo. However, targeting QS signals alone is not enough to prevent bacterial infections. Drug resistance and recurrence of biofilms makes it difficult to eradicate. Herein, photodynamic therapy (PDT) is selected to unite QSIs and antibiotics. A synergistically antibiofilm system, which combines QSIs, antibiotics, and PDT based on hollow carbon nitride spheres (HCNSs) is envisaged. First, HCNS provides the multidrug delivering ability, enabling QSIs and antibiotics to be released in sequence. Subsequently, multistage releases sensitize bacteria effectively, potentiating the chemotherapeutic effects of the antibiotics. Finally, the integration of QSIs and PDT not only minimizes the possibility of drug resistance, but also overcomes the problem of limited mass and extension of PDT. Even after 48 h of incubation, the bacterial biofilm is obviously inhibited. And its biofilm disperse efficiency exceeds 48% (compared with QSI‐potentiated chemotherapy group) and 40% (compared with PDT group). Besides, the inhibition of the QS system influences phenotypes related to virulence factor production and surface hydrophobicity, which weaken biofilm invasion and formation. Eventually, this system is applied to disperse bacterial biofilm in vivo. Overall, PDT and QS modulation are devoted to eradicate drug resistance and recurrence of the biofilm. 相似文献
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Specific Oxygenated Groups Enriched Graphene Quantum Dots as Highly Efficient Enzyme Mimics 下载免费PDF全文
Huan Wang Chaoqun Liu Zhen Liu Jinsong Ren Xiaogang Qu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(13)
Significant progress is achieved for the utilization of graphene quantum dots as enzyme mimics in various biomedical fields recently. Although promising, the biocatalytic performance is far from satisfactory. Here, the rational design and synthesis of specific oxygenated groups enriched graphene quantum dots (o‐GQDs) via a facile oxidation reflux route is reported. These well‐prepared o‐GQDs with uniform size exhibit an ultrahigh peroxidase‐like activity in a wide range of pH values, and their superior performance is verified by using glucose detection as a typical model. Compared with classical nanozymes, these o‐GQDs show multiple times higher enzymatic activity. It is believed that the super facile synthesis strategy can greatly facilitate the practical use of o‐GQDs as enzyme mimics in the future. 相似文献
7.
《International Journal of Hydrogen Energy》2020,45(27):13939-13946
Vacancies engineering was widely reported as the promising strategy for the improvement of the photocatalytic performance of semiconductor photocatalysts. In current work, carbon vacancies are constructed successfully in graphitic carbon nitride (g-C3N4) photocatalyst via magnesium vapor etching. Experimental results show that the formed carbon vacancies in g-C3N4 photocatalyst can significantly improve the photocatalytic H2 generation performance. XRD, FTIR, SEM/TEM, XPS and PL characterization data are employed to evidence the construction of carbon vacancies, which are revealed to be the reason for the enhancement of photocatalytic H2 evolution. This work develops an alternative route to construct carbon vacancies in g-C3N4 materials and gives an insight into the influence of vacancies on the photocatalytic performance of photocatalysts. 相似文献
8.
《International Journal of Hydrogen Energy》2020,45(1):565-573
Bimetallic phosphides have been widely investigated as electrocatalysts for oxygen evolution reaction (OER) due to their efficient activity and environmental friendliness. While the reasonable design and controllable synthesis of bimetallic phosphide with typical nanostructure is still a great challenge. Hence, we put forward a novel and straightforward way for constructing FeP nanoparticles coated Ni2P ultrathin nanotube arrays on the surface of Ni foil (FeP@Ni2P/NF), which is synthesized through two steps of electrodeposition and subsequent in-situ phosphorization process. The obtained FeP@Ni2P/NF shows excellent electrochemical activity for OER, and it only needs potential of 1.52 V vs. RHE to reach the current density of 50 mA cm−2 in an alkaline media. The excellent electrocatalytic activity of FeP@Ni2P/NF mainly benefits from: (i) the synergistic effect between FeP and Ni2P promoting electron transfer; (ii) the formation of the unique 3D ultrathin nanotube arrays increasing the quantity of active sites and avoiding the agglomeration of catalysts during testing. In addition, the influence of reaction condition on the electrochemical activity for OER has also been investigated through altering the phosphorization temperature of precursor. 相似文献
9.
《International Journal of Hydrogen Energy》2020,45(11):6529-6537
MnO-MnCx coated carbon nanotubes (MnO/MnCx/CNTs) nanocomposites were prepared by a one-pot deposition method. The coating consisted of MnO, Mn5C2, Mn15C4 and Mn23C6 was formed on the surface of CNTs by heating a mixture of Mn particles and CNTs at 600 °C for 40 min under vacuum. Then after heated MnO/MnCx/CNTs in air at 350 °C for 2 h, MnO nanoparticles were partially converted to Mn3O4 nanosheets. Then Mn3O4-MnCx coated carbon nanotubes (Mn3O4/MnCx/CNTs) composed of interconnected nanosheets structure were successfully synthesized by a two-step method of one-pot deposition and heat post-treatment. The Mn3O4/MnCx/CNTs showed better oxygen reduction reaction performance in alkaline condition than MnO/MnCx/CNTs and pristine CNTs. Besides, the formed MnCx (Mn5C2 and Mn23C6) by one-pot deposition method provided a strong interface bonding between Mn3O4 and CNTs, leading to improved stability of Mn3O4/MnCx/CNTs as an electrode material. 相似文献
10.
《International Journal of Hydrogen Energy》2020,45(11):6425-6436
Graphitic carbon nitride (g-C3N4) is a promising metal-free photocatalyst for solar photocatalytic hydrogen gas (H2) generation from water. In particularly, high-crystalline g-C3N4 (GCN-HC) material with fewer structural defects possesses the fast photoexcited electron-hole pair's separation efficiency as comparison with bulk g-C3N4 (GCN-B) powders, leading to the drastic improvement of photocatalytic activity. However, the fabrication of such GCN-HC photocatalyst by a simple and economical synthesis approach still remains a challenge. Herein, we firstly develop a one-step rapid polymerization strategy for synthesizing the GCN-HC, that is direct calcination of melamine at 550 °C not only without the early heating process, but also without the assistance of any additive or salt intercalation. As a result, the GCN-HC exhibits an obviously boosting visible-light-induced photocatalytic H2-generation performance, which is over 2.06-folds much greater than that of GCN-B. Our work provides an available one-step synthetic strategy for the large-scale preparation of high performance GCN-HC towards sustainable solar-to-chemical energy conversion. 相似文献