A mid-infrared spectroscopy-random forest system for the origin tracing of Chinese geographical indication Aconiti Lateralis Radix Praeparata.

Reliable origin certification methods are essential for the protection of high-value genuine medicinal material with designated origins and geographical indication (GI) products. Aconiti Lateralis Radix Praeparata (Fuzi), one well-known traditional Chinese medicine and geographical indication products have remarkable efficacy and wide clinical application, with high demand in domestic and international markets. The efficacy and price of Fuzi from different origins vary, and it is difficult for the general public to accurately identify them through traditional experience. The mass spectrometry detection technology based on the plant metabolomics is tedious and lengthy in test sample preparation, complicated in operation, long in detection time, and low in reproducibility. As a sophisticated, green, fast, and low-loss detection technique, infrared spectroscopy is integrated by machine learning to bring new ways for quality regulation and control of traditional Chinese medicines. An analytical method based on mid-infrared spectroscopy combined with a random forest algorithm was developed to verify the geographical origin of authentic herbs and/or GI products. The method successfully predicted and classified three varieties of Chinese GI Fuzi and four varieties of non-GI Fuzi. In this study, an environment-friendly traceability strategy with fast analysis, low sample loss and high precision was used to provide a new strategy for identifying the origin of Fuzi.

Discrimination of Curculigo orchioides Rhizoma and Curculigo glabrescens Rhizoma using stable isotope and mineral element analyses coupled with chemometrics.

Correct species identification is crucial for ensuring the quality, safety, and efficacy of herbal medicine. Market research indicates that Curculigo glabrescens Rhizoma (CGR) was the major counterfeit of the medicine Curculigo orchioides Rhizoma (COR). To accurately discriminate COR and CGR remains a challenge, and it becomes even more difficult when the herbs have been heavily processed into a powder. In this work, combined with high performance liquid chromatography analysis, a novel component in CGR was discovered, and two stable isotopes (N%, C%, δ15N, δ13C) and nineteen mineral elements were determined along with multivariate statistical analysis to distinguish the authentic COR samples and counterfeit CGR samples. The results showed that there were significant differences between the mean value of N%, δ15N and δ13C according to the botanical origins. In addition, these two species can be differentiated by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) analysis. A linear discriminant analysis (LDA) model with a good classification rate (100%) and cross-validation rate (100%) was established. Hence, stable isotope and mineral element contents combined with chemometrics analysis could be considered as an effective and reliable method for discriminating the source species of COR and CGR.

Preparation and characterization of vanillin-chitosan Schiff base zinc complex for a novel Zn2+ sustained released system.

In this work, a novel sustained released system (VCSB-Zn(II)) for zinc supplements was built by vanillin-chitosan Schiff base (VCSB) chelated with Zn2+ to improve the zinc trace element utilization ratio. Samples were characterized by FT-IR, 1H NMR, XRD, SEM, and TGA. The results showed that VCSB exhibited a more excellent chelation capacity of Zn2+ than chitosan. The chelation capacity of VCSB was about 1.7 times more than that of chitosan, corresponding to 50.96 mg/g and 29.91 mg/g, respectively. Furthermore, VCSB-Zn(II) showed excellent sustained released performance at simulated gastric fluid because of the acid slow-dissolving ability. And the higher the CN content of VCSB, the higher the cumulative release rate (Ri) of Zn2+, the highest Ri reached 77.81%. The sustained released curves were described by the first-order and Korsmeyer-Peppas equation, which described the Zn2+ sustained released performance caused by the dissolution of VCSB-Zn(II) and Fick diffusion. This Zn2+ sustained released system shows great potential in the application in the field of trace elements supplements for animals.

Extinction blunts paraventricular thalamic contributions to heroin relapse.

Here, we use optogenetics and chemogenetics to investigate the contribution of the paraventricular thalamus (PVT) to nucleus accumbens (NAc) pathway in aversion and heroin relapse in two different heroin self-administration models in rats. In one model, rats undergo forced abstinence in the home cage prior to relapse testing, and in the other, they undergo extinction training, a procedure that is likened to cognitive behavioral therapy. We find that the PVT→NAc pathway is both sufficient and necessary to drive aversion and heroin seeking after abstinence, but not extinction. The ability of extinction to reduce this pathway's contribution to heroin relapse is accompanied by a loss of synaptic plasticity in PVT inputs onto a specific subset of NAc neurons. Thus, extinction may exert therapeutic reductions in opioid seeking by altering synaptic plasticity within the PVT→NAc pathway, resulting in reduced aversion during opioid withdrawal as well as reduced relapse propensity.

Preparation of TTO/UF resin microcapsule via in situ polymerisation and modelling of its slow release.

For slow release of tea tree oil (TTO), TTO were encapsulated by urea-formaldehyde (UF) resin via in situ polymerisation. The effects of curing time and drying condition on particle size, and TTO loading of the TTO/UF microcapsules were investigated. The results indicated that TTO/UF resin microcapsules with curing time of 80 min had narrow size distribution and good wall cover. Drying at ambient was better to maintain the TTO content than drying at oven. The loading of TTO with curing time of 80 min can be up to 45 wt.% of the mass-proportion to the prepared microcapsules, and more than 90 wt.% of the loaded TTO could be sustainably released in about 5 days. Moreover, the release kinetics of TTO/UF microcapsules was well described by Ritger-Peppas model, revealing non-Fickian diffusion. Promisingly, TTO/UF microcapsules with good stability can be used as a slow release vehicle for antibacterial application.

Influences of different Fe sources on Fe bioavailability and homeostasis in SD rats.

The purpose of this study was to determine whether the enteric coating process affects growth performance, Fe bioavailability, and gene expression levels that maintain iron balance in the body. The test was divided into the control group, ferrous sulfate group, ferrous fumarate group, ferrous glycine chelate(1:1) (Fe-Gly(1:1)) group, ferrous glycine chelate(2:1) (Fe-Gly(2:1)) group, enteric-coated Fe-Gly(1:1) group, and enteric-coated Fe-Gly(2:1) group. The results showed that the growth performance of the rats in each iron supplement group was no significant difference among them. The results of serum biochemical indicators showed that the antioxidant capacity of the rats in the iron supplement group after enteric coating increased. The iron supplementation effect of Fe-Gly(1:1) and Fe-Gly(2:1) was better than that of ferrous sulfate, and the effect of Fe-Gly(1:1) after enteric coating was enhanced. The expression levels of IRP1 and IRP2 in the genes of enteric-coated Fe-Gly(1:1) and enteric-coated Fe-Gly(2:1) were significantly higher than those of ferrous sulfate. The expression levels of IRP1 and IRP2 in the protein of enteric-coated Fe-Gly(1:1) group were significantly higher than those in the Fe-Gly(1:1) group. The above results show that Fe-Gly can improve the bioavailability and antioxidant capacity of iron and reduce the iron output of feces after enteric coating.

Preparation of ZnO Nanoparticles with High Dispersibility Based on Oriented Attachment (OA) Process.

Understanding nanoparticle growth mechanisms is crucial for the synthesis of nanocrystals with desired biological and chemical properties. Growth of nanocrystals by oriented attachment (OA) is frequently reported as a method supplementary to the classical growth by Ostwald ripening (OR) process. In this work, ZnO nanoparticles (NPs) were prepared by wet chemical method. Size/shape evolution of ZnO NPs in ethanol solution was systematically studied using transmission electron microscopy (TEM), dynamic light scattering (DLS), and X-ray diffraction (XRD). In addition, a detailed process of the nanoparticle growth-based OA mechanism is discussed. Results revealed that reaction conditions affect size/shape of NPs and change their surface structure: prior to OA, the surface of adjacent particles transformed into their "rough" states. We proved that stability of the solution was significantly improved in this state. Such a state is important to design nanoparticles with high stability and as nano-suspensions with special physical and/or chemical properties. This state is a critical step in enhancing OA process.

[Study on dynamic accumulation of index components from Bupleurum chinense in various collecting periods].

OBJECTIVE: To study the dynamic change law of volatile oil, saikosaponin a, d and alcohol-extract from Bupleurum chinense at Songxian region in Henan province, and to explore the optimal harvest period of Bupleurum chinense. METHODS: With the contents of saikosaponin a and d, absorbance of volatile oil and percentage of alcohol-extract as indexes, HPLC-ELSD and ultraviolet spectrophotometry were successively used to analyze them. RESULTS: There are obvious differences among the contents of volatile oil, saikosaponin a, d and alcohol-extract in various collecting periods sample, the absorption of volatile oil in distillation was the highest in October, the content of saikosaponin a was the highest in September, the saikosaponin d in December and the percentage of alcohol-extract in October. CONCLUSION: The optimal harvest period of Bupleurum chinense at Songxian region in Henan is identified, which can provide scientific basis for crude drug production and processing.

Inhibitory kinetics of paeonol on the activity of mushroom tyrosinase oxidizing L-dopa.

AIM: To evaluate the effect of paeonol on the activity of tyrosinase and provide experimental evidence for the treatment of hyperpigmentation disorders. METHODS: Tyrosinase activity was estimated by measuring the oxidation rate of L-3,4-dihydroxyphenylalanine (L-Dopa). The inhibitory effects of paeonol on the activity of mushroom tyrosinase and Michaelis-Menten kinetics were deduced from the Lineweaver-Burk plots. RESULTS: The inhibitory concentration of paeonol leading to 50% enzyme activity lost (IC50) was estimated to be 0.60 mmol x L(-1). The inhibition constants for paeonol binding free enzyme, K(I), and substrate-enzyme, K(IS), are 0.084 and 0.12 mmol x L(-1), respectively. CONCLUSION: Paeonol is a potential mixed inhibitor of mushroom tyrosinase. The mixed inhibition function may originate from its ability to form a Schiff base with a primary amino group and to chelate copper at the active site of tyrosinase.