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Sample preparation, including extraction, separation, and purification, is a vital process for natural product analysis. As an attractive sample pretreatment method, magnetic solid‐phase extraction (MSPE) has gained plenty of attention, mainly due to its simpler operation, less consumption of organic solvents, and shorter processing time than traditional SPE. This updated review is devoted to summarizing the applications of MSPE based on different magnetic nanomaterials in the analysis of various natural products in complex matrixes, such as biological samples, plants, and Chinese herbal preparations in the past four years (2020–2023). The preparation and fabrication of different materials are briefly introduced. Furthermore, the extraction mechanism and interaction forces between adsorbent and analytes are elaborated, and the advantages and disadvantages of different adsorbents coupled with various analytical methods for MSPE of different natural products are summarized. Moreover, the future trends and opportunities for MSPE in the natural product analysis are discussed. It is expected that this work can provide updated information for future research on the applications of MSPE in such fields. [ABSTRACT FROM AUTHOR]

The development of a facile and reliable assay for arsenic (As) detection is crucial for its pollution control, which is a well-known heavy-metal pollutant in the environment. In this work, an efficient colorimetric method was established for As(V) detection based on a novel cuboid-shape Mn-Urea nanozyme (UMnzyme) with arsenic-enhanced oxidase-like activity. The UMnzyme was prepared through the coordination of Mn ions and carbonyl groups in urea, which possesses outstanding oxidase-like activity that can generate the superoxide anion free radical (O2˙−) by catalyzing the dissolved O2, triggering the 3,3′,5,5′-tetramethylbenzidine (TMB) chromogenic reaction. Furthermore, the free oxygen atoms in UMnzyme provide potential sites to bind with As, in which the formation of As–O will not destroy the morphology and structure of UMnzyme. The capture of As by UMnzyme results in the improvement of its oxidase-like activity; therefore, a colorimetric method for As(V) detection was developed with a linear range of 12.5–250 μg L−1. The limit of detection was determined to be 2.4 μg L−1 (S/N = 3), which is lower than the threshold (10 ppb) recommended by the World Health Organization. Moreover, the developed method was applied in the detection of As(V) in environmental water, and the recoveries are 89.5–103.6%. In short, this study provides an efficient and reliable strategy for As(V) detection based on a novel Mn-based nanozyme and a new idea for the reasonable design of Mn-based nanozymes with enhanced catalytic performance. [ABSTRACT FROM AUTHOR]

In this work, dopamine (DA) was polymerized on the surface of CuO nanoparticles (CuO NPs) to form a molecularly imprinted polymer (MIP@PDA/CuO NPs) for the colorimetric detection of astragaloside-IV (AS-IV). The synthesis process of MIP is simple and easy to operate, without adding other monomers or initiators. CuO NPs has high peroxidase (POD)-like activity that can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to generate oxidized TMB (OxTMB) in the presence of H2O2, having a maximum ultraviolet-visible (UV-Vis) absorption peak at 652 nm. The AS-IV can specifically bind to the surface imprinted cavities and prevent the entry of TMB and H2O2, which will lead to the inhibition of the catalytic reaction. Therefore, a new approach based on the POD-like activity of MIP@PDA/CuO NPs for AS-IV detection was developed with a linear range from 0.000341 to 1.024 mg/mL. The LOD and LOQ are 0.000991 and 0.000341 mg/mL, respectively. The developed method can accurately determine AS-IV in Huangqi Granules and different batches of Ganweikang Tablets, which are similar to the results measured by HPLC-ELSD and meet the requirements of Chinese Pharmacopoeia (2020 edition) for the amount of AS-IV in Huangqi Granules. The combination of MIP with CuO NPs not only endows the detection of AS-IV with high selectivity and reliability, but also expands the application of nanozymes in the detection of small-molecule compounds that have weak UV absorption, and do not have reducibility or oxidation properties. [ABSTRACT FROM AUTHOR]

Phenolic compounds are one of the main organic pollutants in the environment that can seriously affect ecosystems, even at very low concentrations. Due to the resistance of phenolic compounds to microorganisms, conventional biological treatment methods face challenges in effectively addressing this pollution problem. In this study, a novel laccase mimic (Tris-Cu nanozyme) is prepared using a simple and rapid synthesis strategy based on the coordination of copper ions and amino groups in Tris(hydroxymethyl)aminomethane (Tris). It is found that the Tris-Cu nanozyme exhibits good catalytic activity against a variety of phenolic compounds, the Km, Vmax and Kcat are determined to be 0.18 mM, 15.62 μM·min−1 and 1.57 × 107 min−1 using 2,4-dichlorophenol (2,4-DP) as the substrate, respectively. Then, based on the laccase-like activity of the Tris-Cu nanozyme, a novel colorimetric method for 2,4-DP (the limit of detection (LOD) = 2.4 μM, S/N = 3) detection in the range of 10–400 μM was established, and its accuracy was verified by analyzing tap and lake water samples. In addition, the Tris-Cu nanozyme shows excellent removal abilities for six phenolic compounds in experiments. The removal percentages for 2,4-DP, 2-chlorophenol (2-CP), phenol, resorcinol, 2,6-dimethoxyphenol (2,6-DOP), and bisphenol A (BPA) are 100%, 100%, 100%, 100%, 87%, and 81% at 1 h, respectively. In the simulated effluent, the Tris-Cu nanozyme maintains its efficient catalytic activity towards 2,4-DP, with a degradation percentage of 76.36% at 7 min and a reaction rate constant (k0) of 0.2304 min−1. Therefore, this metal–organic complex shows promise for applications in the monitoring and degrading of environmental pollutants. [ABSTRACT FROM AUTHOR]

A core–shell-derived structural magnetic zeolite imidazolate framework-67 (Fe3O4-COOH@ZIF-67) nanocomposite was fabricated through a single-step coating of zeolite imidazolate framework-67 on glutaric anhydride-functionalized Fe3O4 nanosphere for the magnetic solid-phase extraction (MSPE) of theophylline (TP). The Fe3O4-COOH@ZIF-67 nanocomposite was characterized through scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy, Zeta potential analysis, X-ray diffraction, Brunauer–Emmett–Teller, and vibrating sample magnetometer. The material has a high specific surface area and good magnetism, which maintains the regular dodecahedron structure of ZIF-67 without being destroyed by the addition of Fe3O4-COOH nanospheres. The Fe3O4-COOH@ZIF-67 can rapidly adsorb TP mainly through the strong coordination interaction between undercoordinated Co2+ on ZIF-67 and –NH from imidazole of TP. The adsorption and desorption conditions, such as the amount of adsorbent, adsorption time, pH value, and elution solvent, were optimized. The kinetics of TP adsorption on Fe3O4-COOH@ZIF-67 was found to follow pseudo-second-order kinetics. The Langmuir model fits the adsorption data well and the maximum adsorption capacity is 1764 mg/g. Finally, the developed MSPE-HPLC method was applied in the enrichment and analysis of TP in four tea samples and rabbit plasma. TP was not detected in oolong tea and rabbit plasma, and its contents in jasmine tea, black tea, and green tea are 5.80, 4.31, and 1.53 μg/g, respectively. The recoveries of spiked samples are between 74.41% and 86.07% with RSD in the range of 0.81–3.83%. The adsorption performance of Fe3O4-COOH@ZIF-67 nanocomposite was nearly unchanged after being stored at room temperature for at least 80 days and two consecutive adsorption–desorption cycles. The results demonstrate that Fe3O4-COOH@ZIF-67 nanocomposite is a promising magnetic adsorbent for the preconcentration of TP in complex samples. [ABSTRACT FROM AUTHOR]

Polysaccharides exhibit multiple pharmacological activities, which are closely related to their structural characteristics. Therefore, quantitative quality control of polysaccharides based on chemical properties is of importance for their applications. However, polysaccharides are mixed macromolecular compounds that are difficult to separate, and the lack of standards made direct quantification more difficult. In this study, we proposed a new quantitative method based on the released specific oligosaccharides for polysaccharides from Lentinus edodes (shiitake) and other related fungi. Specific oligosaccharides were firstly released from polysaccharides using 1,3- β -glucanase, then derivatized with 2-aminobenzamide (2-AB), which further separated by hydrophilic interaction chromatography (HILIC) and quantitatively determined by UPLC coupled with fluorescence detector (FLR). Laminaritriose was used as the universal standard for quantification of all the oligosaccharides. This method was validated according to linearity, limit of detection, limit of quantitation, precision, accuracy, repeatability and stability. In addition, the four specific oligosaccharides released from polysaccharides in L. edodes were qualitatively analyzed by extracted ion chromatogram (EIC) from UPLC-MS profiles, which were identified to be disaccharide, trisaccharide and tetrasccharide. The proposed strategy not only realized the quantitative analysis of polysaccharides by UPLC-FLR, but also could achieve the qualitative distinction of different polysaccharides. [Display omitted] • A new qualitative and quantitative method was developed for fungi polysaccharides. • Specific oligosaccharides were released from polysaccharides using a selected enzyme. • The chemical structures of released specific oligosaccharides were speculated. • This method was superior to PACE, especially the feasibility of quantification. [ABSTRACT FROM AUTHOR]

One new expoxy nortriterpenoid (1) and one new ergostane-type steroid (2), together with seven known steroids (3–9), were obtained from the fruiting bodies of the fungusGanoderma resinaceum. The new compounds were elucidated on the basis of extensive spectroscopic data (MS, NMR, IR, and UV) and the known compounds were identified by comparing spectroscopic data with those reported in literature. [ABSTRACT FROM PUBLISHER]

The impressive functions of brain circuits have inspired many scientists to attempt in designing neuron analogues by using artificial molecular systems or electronic devices. However, the study of molecular neuron has not produced an equal variety of models. Here, using UV–vis absorption, fluorescence, and resonance light scattering spectroscopies for pH sensing with a common indicator—Congo red dye, we show how Congo red molecules can be used to construct molecular neuron and exhibit neuron-like behavior. Our molecular neural model uses molecular groups as ‘dendrites’ which receive and sense environmental stimuli inputs (pH), molecular matrix as ‘soma’ which acts as the summation function, and the change in optical characteristics as ‘axon’ which represents outputs. Our approach allows us to utilize simple sensing molecules as McCulloch-Pitts neuron for experimental implementation of large-scale logic computation in batch mode and to use extraordinary information density inherent in molecular neuron for alphanumeric information encoding and molecular cryptography. Our results suggest that molecules could be used as universal artificial neurons with the capability of sensing analytes or environmental stimuli, remembering patterns of molecular events, and making decisions. [ABSTRACT FROM AUTHOR]

Objective: Tanezumab is a new therapeutic intervention for patients with osteoarthritis (OA) of the knee. We performed the present meta-analysis to appraise the efficacy and safety of tanezumab for patients with knee OA. Methods: We systematically searched randomized controlled trials from PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL). The primary outcomes were mean change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, the WOMAC physical function and patient's global assessment (PGA). Outcomes were reported as the standard mean difference (SMD) or relative risk (RR) with 95% confidence interval (CI). We assessed the pooled data using a random-effects model. Results: Of the identified studies, four were eligible and were included in this meta-analysis (N = 1839 participants). Compared with the placebo groups, tanezumab yielded a significant reduction in mean change in the WOMAC pain (SMD = 0.51, 95% CI 0.34 to 0.69, P<0.00001), the WOMAC physical function (SMD = 0.56, 95% CI 0.38 to 0.74, P<0.00001) and PGA (SMD = 0.34, 95% CI 0.22 to 0.47, P<0.00001). There was no significant difference in serious adverse events (RR = 1.06, 95% CI 0.59 to 1.92, P = 0.84) between the tanezumab and placebo groups. Tanezumab significantly increased discontinuations due to adverse events (RR = 2.89, 95% CI 1.59 to 5.26, P = 0.0005), abnormal peripheral sensations (RR = 3.14, 95% CI 2.12 to 4.66, P<0.00001), and peripheral neuropathy (RR = 6.05, 95% CI 2.32 to 15.81, P = 0.0002). Conclusion: Tanezumab can alleviate pain and improve function for patients with OA of the knee. However, considering the limited number of studies, this conclusion should be interpreted cautiously and more clinical randomized controlled trials are needed to verify the efficacy and safety of tanezumab for OA of the knee. [ABSTRACT FROM AUTHOR]

A novel method for direct determination of Al(III) by using hemin-functionalized graphene (H-GO) has been established based on the enhancement of resonance Rayleigh scattering (RRS) intensity. The characteristics of RRS spectra, the optimum reaction conditions, and the reaction mechanism have been investigated. In this experiment, the Al(III) would exist in sol–gel Al(OH) 3 species under the condition of pH 5.9 in aqueous solutions. When H-GO existed in the solution, the sol–gel Al(OH) 3 would react with H-GO and result in enhancement of RRS intensity, owing to the enhanced hydrophobicity of H-GO surface. Therefore, a simple and rapid sensor for Al(III) was developed. The increased intensity of RRS is directly proportional to the concentration of Al(III) in the range of 10 nM–6 μM, along with a detection limit of 0.87 nM. Moreover, the sensor has been applied to determination of Al(III) concentration in real water and aspirin tablet samples with satisfactory results. Therefore, the proposed method is promising as an effective means for selective and sensitive determination of Al(III). [ABSTRACT FROM AUTHOR]

Context: The preferred treatment for osteoporosis in men is debated, and pairwise meta-analysis cannot obtain hierarchies of these treatments. Objective: The objective of this study was to integrate the evidence and provide hierarchies of eight drugs based on their effect on the bone mineral density in the lumbar spine (BMD in LS) and the fracture rate. Data Sources: Eligible studies were identified by searching Amed, British Nursing Index, EMBASE, PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar, SIGLE, the National Technical Information Service, the National Research Register (UK), and the Current Controlled Trials databases. Study Selection: RCTs or quasi-RCTs reporting at least two drugs (two active drugs or one active drug and a placebo) used to treat osteoporosis in men were selected by two authors. Data Extraction: Two authors independently extracted the data. Data Synthesis: Thirteen studies involving 3647 patients were included. Compared with placebo therapy, zoledronate (SMDs 13.48, 95% credible intervals 11.88-15.08) yielded the most significant effect on increasing the BMD in LS, followed by alendronate (11.04, 9.68-12.41), teriparatide (20mcg) + risedronate (10.98, 8.55-13.48), risedronate (10.33, 8.68-12.01), teriparatide (20mcg) (9.33, 6.87-11.76), strontium ranelate (8.88, 7.51-10.24), ibandronate (5.49, 3.82-7.16), parathyroid hormone (1-84) (4.89, 3.12-6.62) and alfacalcidol (3.42, 1.7-5.2). Placebo therapy had a significantly higher fracture rate in contrast to risedronate (OR 2.51, 95% CrI 1.23-4.24) or zoledronate (2.92, 1.29-5.62) or teriparatide (20mcg) (4.04, 1.36-8.49) or teriparatide (40mcg) (3.5, 1.14-8.34). Zoledronate ranked first for increasing the BMD in LS, and teriparatide (20mg) was ranked first for decreasing the fracture rate. Conclusions: Zoledronate might be the best choice to increase the BMD in LS and teriparatide (20mg) might lead to the lowest fracture rate. [ABSTRACT FROM AUTHOR]

Purpose: The question which kind of methods is most suitable for treating the old people for osteoporotic vertebral compression fracture is still discussed and pairwise meta-analyses cannot get hierarchies of these treatments. Our aim is to integrate the evidence to provide hierarchies of the comparative efficacy measured by the change of VAS (Visual Analogue Scale) and tolerability measured by incidence of new fractures and risk of all-cause discontinuation on three treatments (percutaneous vertebroplasty (PVP)、balloon kyphoplasty (BK) and conservative treatment(CT)). Methods: We performed a Bayesian-framework network meta-analysis of randomized controlled trials (RCTs) to compare three treatments for the old people with osteoporotic vertebral compression fracture. The eligible RCTs were identified by searching Amed, British Nursing Index, Embase, Pubmed, the Cochrane Central Register of Controlled Trials (CENTRAL), Google scholar, SIGLE, the National Technical Information Service, the National Research Register (UK) and the Current Controlled Trials databases. Data from three outcomes (e.g. VAS, risk of all-cause discontinuation and incidence of new fractures) were independently extracted by two authors. Results: A total of five RCTs were finally included into this article. PVP and BK significantly decreased VAS when compared with CT. BK had a significantly lower risk of all-cause discontinuation contrast to CT. Three treatments (BK, PVP and CT) had no significant differences in the incidence of new fractures. Conclusions: PVP may be the best way to relieve pain, CT might lead to the lowest incidence of new fractures and BK might had the lowest risk of all-cause discontinuation in old people with osteoporotic vertebral compression fracture. More large-scale and longer duration of follow-up studies are needed. [ABSTRACT FROM AUTHOR]

Context: Alendronate may relate to the incidence of cancers, especially esophageal and colon cancer. But the results are inconsistent in different studies. Objective: To quantify the association between the use of alendronate and the occurrence of different types of cancer. Data Sources: We searched Embase, Pubmed, CENTRAL, SIGLE and , up to 2014 June. Study Selection: Cohort studies reporting association between alendronate or bisphosphonate therapy including alendronate in patients with osteoporosis and risk of cancer were selected by two authors. Data Extraction: Two authors independently extracted the data. The Chi-square test and the I-square test were used for testing heterogeneity between studies. Data Synthesis: Eight cohort studies were included in the meta-analysis. Meta-analysis result manifested that alendronate significantly increased the incidence of lung cancer (HR 1.23, 95%CI 1.03 to 1.47, P value = 0.03), nevertheless, there was no significant difference after we excluded either Lee’s 2012 study (HR 1.17, 95%CI 0.95 to 1.44, P value = 0.13) or Chiang’s 2012 study (HR 1.47, 95%CI 1 to 2.17, P value = 0.05). For the incidence of colorectal cancer, no significant difference occurred (HR 0.91, 95%CI 0.74 to 1.13, P value = 0.39), but there was a positive relationship when we used fixed model (HR 0.85, 95%CI 0.78 to 0.93, P value = 0.004). For the incidence of liver cancer, there was no significant difference (HR 1.36, 95%CI 0.9 to 2.04, P value = 0.14), however, the result changed after we excluded Chiang’s 2012 study (HR 1.69, 95%CI 1.03 to 2.77, P value = 0.04). There was no significant difference in other types of cancer. Conclusion: Based on current evidences, alendronate therapy may be associated with a high risk of lung cancer, may with an excess risk of liver cancer, a low risk of colorectal and no related risk of other cancers. [ABSTRACT FROM AUTHOR]

Background and Aims: Whether Saccharomyces boulardii (S boulardii) as an adjuvant therapy are beneficial to H pylori eradication remains controversial. The aim of the study was to update and determine the effects of S boulardii as an adjuvant therapy on H pylori eradication rates and adverse effects. Methods: We searched PubMed, Embase, CENTRAL, and Web of Science to collect all randomized controlled trials assessing the effects of S boulardii as an adjuvant therapy for H pylori eradication from inception to February 2019. Quality of evidence was appraised using Grading of Recommendations, Assessment, Development and Evaluation system. Trial sequential analysis was performed to control the risk of type I and type II errors. Results: Eighteen trials with 3592 patients were eligible for meta‐analysis. Compared with standard eradication regimen, the S boulardii supplementation could significantly improve eradication rates [risk ratio (RR) = 1.09, 95% confidence interval (CI):1.05‐1.13; moderate quality evidence] and reduce the incidence of total side effects (RR = 0.47, 95%CI:0.36‐0.61; low quality evidence), as well as some gastrointestinal adverse effects, especially diarrhea (RR = 0.33, 95%CI:0.23‐0.47; low quality evidence) and constipation (RR = 0.37, 95%CI:0.23‐0.57; moderate quality evidence). In addition, the need for discontinuation rate in S boulardii supplementation group was significantly lower than in the control group (RR = 0.33, 95%CI:0.16‐0.69, P = .003; moderate quality evidence). The TSA results for overall eradication rates and total side effects indicated that the effects were conclusive. Conclusions: Our meta‐analysis shows that S boulardii supplementation on standard eradication therapy significantly increased H pylori eradication rates and reduced the incidence of total side effects and some gastrointestinal adverse effects during eradication therapy. [ABSTRACT FROM AUTHOR]

Ganoderma resinaceum has been used as an ethnomedicine for lowering blood sugar. To clarify the bioactive chemical constituents contributing to lower blood sugar, chemical investigation on the fruiting bodies of Ganoderma resinaceum was conducted by chromatographic techniques, and led to the isolation of 14 compounds. Their structures were elucidated as triterpenoid lactones (1–4 and 8) and ganoderma acids (5–7 and 9–14) based on the analysis of extensive spectroscopy (mass spectrometry (MS), nuclear magnetic resonance (NMR), infrared (IR), and ultraviolet (UV)) and comparison with literature data. Compounds 3, 5, 6, and 9–14 were evaluated for α-glucosidase inhibitory activity. Compounds 1–7 are new compounds. Compounds 1–4 and 8 were characteristic of an oxaspirolactone moiety, consisting of a five-membered ether ring, a five-membered lactone ring, and a characteristic C-23 spiro carbon. It is rare for natural products that such an oxaspirolactone moiety occurred in the lanostane-type triterpenoids. Compounds 5–7 and 9–14 may be important intermediates of the biosynthetic pathways of 1–4 and 8. Compounds 1 and 2 showed more potent inhibitory activity against α-glucosidase compared with the positive control drug acarbose with IC50 value of 0.75 ± 0.018 mM and 1.64 ± 0.022 mM, respectively. [ABSTRACT FROM AUTHOR]

Eighteen previously undescribed lanostane triterpenes and thirty known analogues were obtained from the fruiting bodies of Ganoderma resinaceum . Resinacein C was isolated from a natural source for the first time. The structures of all the above compounds were elucidated by extensive spectroscopic analysis and comparisons of their spectroscopic data with those reported in the literature. Furthermore, in an in vitro assay, Resinacein C, ganoderic acid Y, lucialdehyde C, 7-oxo-ganoderic acid Z 3 , 7-oxo-ganoderic acid Z, and lucidadiol showed strong inhibitory effects against α-glucosidase compared with the positive control drug acarbose. The structure-activity relationships of ganoderma triterpenes on α -glucosidase inhibition showed that the C-24/C-25 double bond is necessary for α -glucosidase inhibitory activity. Moreover, the carboxylic acid group at C-26 and the hydroxy group at C-15 play important roles in enhancing inhibitory effects of these triterpenes. [ABSTRACT FROM AUTHOR]

The chain conformation, chemical characters and immunomodulatory activity of polysaccharide from Dendrobium devonianum (DDP) were investigated. Results showed that molecular weights, polydispersity index, radius of gyrations of DDP were 3.99 × 10 5  Da 1.27, 74.1 nm, respectively. By applying the polymer solution theory, the exponent (v) values of z 1/2 = kM w v was calculated as 0.38, which revealed that DDP existed as a globular shape in aqueous solution, and further confirmed by AFM analysis. Furthermore, the main monosaccharide compositions were Man and Glc with the ratio of 29.61:1.00. Indeed, the main glycosidic linkages were β-1,4-Manp, and substituted with acetyl groups at O-2 and O-3 position. Notably, DDP could promote the immune functions of macrophages including NO release and phagocytosis. Thus, DDP could be explored as a natural immune-stimulating agent in the health and functional food area as well as pharmaceutical industries. [ABSTRACT FROM AUTHOR]