Recent Progress in Azobenzene-Based Supramolecular Materials and Applications.

Azobenzene-containing small molecules and polymers are functional photoswitchable molecules to form supramolecular nanomaterials for various applications. Recently, supramolecular nanomaterials have received enormous attention in material science because of their simple bottom-up synthesis approach, understandable mechanisms and structural features, and batch-to-batch reproducibility. Azobenzene is a light-responsive functional moiety in the molecular design of small molecules and polymers and is used to switch the photophysical properties of supramolecular nanomaterials. Herein, we review the latest literature on supramolecular nano- and micro-materials formed from azobenzene-containing small molecules and polymers through the combinatorial effect of weak molecular interactions. Different classes including complex coacervates, host-guest systems, co-assembled, and self-assembled supramolecular materials, where azobenzene is an essential moiety in small molecules, and photophysical properties are discussed. Afterward, azobenzene-containing polymers-based supramolecular photoresponsive materials formed through the host-guest approach, polymerization-induced self-assembly, and post-polymerization assembly techniques are highlighted. In addition to this, the applications of photoswitchable supramolecular materials in pH sensing, and CO2 capture are presented. In the end, the conclusion and future perspective of azobenzene-based supramolecular materials for molecular assembly design, and applications are given.

Dietary ß-Hydroxy-ß-Methylbutyrate Supplementation Affects Growth Performance, Digestion, TOR Pathway, and Muscle Quality in Kuruma Shrimp (Marsupenaeus japonicas) Fed a Low Protein Diet.

An 8-week feeding trial was performed to evaluate the effects of dietary ß-hydroxy-ß-methylbutyrate (HMB) supplementation on growth performance and muscle quality of kuruma shrimp (Marsupenaeus japonicas) (initial weight: 2.00 ± 0.01 g) fed a low protein diet. The positive control diet (HP) with 490 g/kg protein and negative control diet (LP) with 440 g/kg protein were formulated. Based on the LP, 0.25, 0.5, 1, 2 and 4 g/kg ß-hydroxy-ß-methylbutyrate calcium were supplemented to design the other five diets named as HMB0.25, HMB0.5, HMB1, HMB2 and HMB4, respectively. Results showed that compared with the shrimp fed LP, the HP, HMB1 and HMB2 groups had significantly higher weight gain and specific growth rate, while significantly lower feed conversion ratio (p < 0.05). Meanwhile, intestinal trypsin activity was significantly elevated in the above three groups than that of the LP group. Higher dietary protein level and HMB inclusion upregulated the expressions of target of rapamycin, ribosomal protein S6 kinase, phosphatidylinositol 3-kinase, and serine/threonine-protein kinase in shrimp muscle, accompanied by the increases in most muscle free amino acids contents. Supplementation of 2 g/kg HMB in a low protein diet improved muscle hardness and water holding capacity of shrimp. Total collagen content in shrimp muscle increased with increasing dietary HMB inclusion. Additionally, dietary inclusion of 2 g/kg HMB significantly elevated myofiber density and sarcomere length, while reduced myofiber diameter. In conclusion, supplementation of 1-2 g/kg HMB in a low protein diet improved the growth performance and muscle quality of kuruma shrimp, which may be ascribed to the increased trypsin activity and activated TOR pathway, as well as elevated muscle collagen content and changed myofiber morphology caused by dietary HMB.

Development of hypothyroidism over 13 years of follow-up of patients with hyperthyroidism after radioiodine therapy.

OBJECTIVE: To analyze the incidence and associated factors of hypothyroidism after radioiodine treatment for hyperthyroidism during a 13-year follow-up period. SUBJECTS AND METHODS: This was a retrospective study of consecutive patients with hyperthyroidism who were treated using a single dose of radioactive iodine (RAI) with a calculated dose regimen from 07/2005 to 12/2012. Univariate and multivariate Cox regression models were used to examine the factors that are associated with the occurrence of hypothyroidism after RAI therapy. Kaplan-Meier analysis was used for confirming associations between these models. RESULTS: A total of 182 patients were included during a 7.5-year median follow-up (range: 6-13 years). They were 36.4±11.1 years. The mean radioactive iodine dosage was 308.2±104.3 (range: 129.5-740.0) MBq. The rates of euthyroidism, early hypothyroidism, improvement, and ineffective treatment at 6 months were 48.4%, 37.9%, 8.8%, and 4.9%, respectively. The cumulative incidence of hypothyroidism in all patients with hyperthyroidism was 45.6% at 1 year, 48.9% at 5 years, and 52.3% at 10 years. Thyroid weight >46g (HR=0.643, 95%CI: 0.422-0.981, P=0.040) and a course of disease of 0.5-3 years (HR=0.592, 95%CI: 0.358-0.981, P=0.042) were identified as independent factors associated with an increased risk of hypothyroidism after radioactive iodine therapy. CONCLUSION: Radioactive iodine treatment with a calculated dose has a high cure rate for hyperthyroidism and has a low annual increase of hypothyroidism. Hypothyroidism after radioactive iodine treatment is more likely to occur in patients with small thyroid and a short disease course.

Edaravone Dexborneol Versus Edaravone Alone for the Treatment of Acute Ischemic Stroke: A Phase III, Randomized, Double-Blind, Comparative Trial.

BACKGROUND AND PURPOSE: Edaravone dexborneol, comprised of 2 active ingredients, edaravone and (+)-borneol, has been developed as a novel neuroprotective agent with synergistic effects of antioxidant and anti-inflammatory in animal models. The present clinical trial aimed at testing the effects of edaravone dexborneol versus edaravone on 90-day functional outcome in patients with acute ischemic stroke (AIS). METHODS: A multicenter, randomized, double-blind, comparative, phase III clinical trial was conducted at 48 hospitals in China between May 2015 and December 2016. Inclusion criteria included patients diagnosed as AIS, 35 to 80 years of age, National Institutes of Health Stroke Scale Score between 4 and 24, and within 48 hours of AIS onset. AIS patients were randomized in 1:1 ratio into 2 treatment arms: 14-day infusion of edaravone dexborneol or edaravone injection. The primary end point was the proportion of patients with modified Rankin Scale score ≤1 on day 90 after randomization. RESULTS: One thousand one hundred sixty-five AIS patients were randomly allocated to the edaravone dexborneol group (n=585) or the edaravone group (n=580). The edaravone dexborneol group showed significantly higher proportion of patients experiencing good functional outcomes on day 90 after randomization, compared with the edaravone group (modified Rankin Scale score ≤1, 67.18% versus 58.97%; odds ratio, 1.42 [95% CI, 1.12-1.81]; P=0.004). The prespecified subgroup analyses indicated that a greater benefit was observed in female patients than their male counterparts (2.26, 1.49-3.43 versus 1.14, 0.85-1.52). CONCLUSIONS: When edaravone dexborneol versus edaravone was administered within 48 hours after AIS, 90-day good functional outcomes favored the edaravone dexborneol group, especially in female patients. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02430350.

14N NMR as a General Tool to Characterize the Nitrogen-Containing Species and Monitor the Nitration Process.

The usefulness of 14N NMR spectroscopy was highly underestimated compared with 15N NMR, which usually required tedious and expensive 15N-labeling manipulations. It is of great significance to make the 14N NMR spectroscopy convenient and useful considering 14N nuclei's high natural abundance of 99.6%. Herein, lots of efforts have been made to generalize routine 14N NMR to characterize nitrogen-containing species by tuning the balance between the solubility and viscosity of the samples. Satisfactory 14N NMR spectra of more than 60 nitrogen-containing compounds have been recorded, and the chemical shifts and the peaks' full width at half-maxima of more than 10 nitrogen-based functionalities have been summarized. Successful monitoring of the ortho-selective nitration of aniline has been demonstrated using the 14N NMR protocol developed in this paper, which will help realize the visualization of nitration processes in the industry.

The N-terminus of MTRR plays a role in MTR reactivation cycle beyond electron transfer.

In eucaryotic cells, methionine synthase reductase (MSR/MTRR) is capable of dominating the folate-homocysteine metabolism as an irreplaceable partner in electron transfer for regeneration of methionine synthase. The N-terminus of MTRR containing a conserved domain of FMN_Red is closely concerned with the oxidation-reduction process. Maternal substitution of I22M in this domain can bring about pregnancy with high risk of spina bifida. A new variation of Arg2del was identified from a female conceiving a fetus with spina bifida cystica. Although the deletion is far from the N-terminal FMN_Red domain, the biochemical features of the variant had been seriously investigated. Curiously, the deletion of arginine(s) of MTRR could not affect the electron relay, if only the FMN_Red domain was intact, but by degrees reduced the ability to promote MTR catalysis in methionine formation. Confirmation of the interaction between the isolated MTRR N-terminal polypeptide and MTR suggested that the native MTRR N-terminus might play an extra role in MTR function. The tandem arginines at the end of MTRR N-terminus conferring high affinity to MTR were indispensable for stimulating methyltransferase activity perhaps via triggering allosteric effect that could be attenuated by removal of the arginine(s). It was concluded that MTRR could also propel MTR enzymatic reaction relying on the tandem arginines at N-terminus more than just only implicated in electron transfer in MTR reactivation cycle. Perturbance of the enzymatic cooperation due to the novel deletion could possibly invite spina bifida in clinics.

Impacts of replacement of dietary fish oil by vegetable oils on growth performance, anti-oxidative capacity, and inflammatory response in large yellow croaker Larimichthys crocea.

A 12-week feeding trial was conducted to evaluate the effects of replacement of dietary fish oil by palm and linseed oils on the growth performance, anti-oxidative capacity, and inflammatory responses of large yellow croaker (initial body weight: 36.82 ± 0.29 g). The control diet was designed to contain 6.5% of fish oil, and named as FO. On the basis of the control diet, the fish oil was 100% replaced by palm and linseed oils, and these two diets were named as PO and LO, respectively. Results showed that the specific growth rate significantly reduced in the PO and LO groups. Crude lipid content in liver of fish fed FO was significantly lower than that in the PO and LO groups. Fatty acid composition in liver reflected the dietary input. Compared with the FO group, palm oil inclusion significantly decreased expressions of superoxide dismutase 1, catalase, and nuclear factor erythroid 2-related factor 2 in liver, while linseed oil inclusion significantly increased expressions of above genes. However, both of the PO and LO groups had a significantly lower total anti-oxidative capacity in liver than the fish fed FO. Dietary palm and linseed oils significantly decreased expressions of arginase I and interleukin 10, and increased expressions of tumor necrosis factor α, interleukin 1ß, toll-like receptor 22, and myeloid differentiation factor 88 in liver. In conclusion, total replacement of dietary fish oil by palm and linseed oils could suppress growth performance and liver anti-oxidative capacity, and induce inflammatory responses of large yellow croaker.

[Application value of whole exome sequencing in critically ill neonates with inherited diseases].

OBJECTIVE: To study the application value of whole exome sequencing (WES) in critically ill neonates with inherited diseases. METHODS: A total of 66 critically ill neonates with suspected inherited diseases or unclear clinical diagnosis who were admitted to the neonatal intensive care unit were enrolled as subjects. The clinical data of the neonates were collected, and venous blood samples were collected from the neonates and their parents for WES. The clinical manifestations of the neonates were observed to search for related pathogenic gene mutations. RESULTS: Among the 66 critically ill neonates with suspected inherited diseases or unclear clinical diagnosis (34 boys and 32 girls), 14 (21%) were found to have gene mutations by WES. One neonate had no gene mutation detected by WES but was highly suspected of pigment incontinence based on clinical manifestations, and multiplex ligation-dependent probe amplification detected a heterozygous deletion mutation in exons 4-10 of the IKBKG gene. Among the 15 neonates with gene mutations, 10 (67%) had pathogenic gene mutation, 1 (7%) was suspected of pathogenic gene mutation, and 4 (27%) had gene mutations with unknown significance. Among the 15 neonates, 13 underwent chromosome examination, and only 1 neonate was found to have chromosome abnormality. CONCLUSIONS: Chromosome examination cannot be used as a diagnostic method for inherited diseases, and WES detection technology is an important tool to find inherited diseases in critically ill neonates with suspected inherited diseases or unclear clinical diagnosis; however WES technology has some limitation and it is thus necessary to combine with other sequencing methods to achieve an early diagnosis.

Apoptosis gene reprograming of human peripheral blood mononuclear cells induced by radioiodine-131 (131I) irradiation.

Background & objectives: The nature of adaptable change of B-cell lymphoma-2 (BCL-2) and/or Bcl2-associated X protein (BAX) gene expression in the human peripheral blood mononuclear cells (PBMCs) irradiated by radioiodine in thyroid diseases therapy is not fully understood. In this study, the alternation of apoptotic gene expression was evaluated while the PBMCs collected from healthy volunteers were irradiated by the radioiodine-131 (131I). Methods: Fasting blood samples were obtained from healthy volunteers. PBMCs from group 0 to 6 were incubated and exposed to different doses of 131I in cell suspension for 6, 12, 24 and 48 h. The apoptosis rates and expression of BCL-2 and BAX genes of PBMCs were examined. Results: The apoptosis rate in the human PBMCs was gradually enhanced after six hour irradiation. The values of BCL-2 and BAX gene expression in groups 1-6 were higher than in group 0 within 6 h of irradiation, and then, these were decreased gradually from 6 to 12 h. BCL: -2 gene expression increased in groups 1-3 after 12 h irradiation, but there was no difference in groups 4-6. The ratio of BCL-2/BAX gene expression among groups 4-6 gradually decreased during the period from 6 to 12 h, and it was significantly lower than in the group 0 at 12, 24 and 48 h. Interpretation & conclusions: The expression of BCL-2 and BAX genes was initially upregulated following irradiation. Later, the balance of BCL-2/BAX genes expression was adjusted, and then, PBMCs underwent apoptosis at higher doses of radiation.

Comparative analysis of glucose metabolism responses of large yellow croaker Larimichthys crocea fed diet with fish oil and palm oil.

In order to study the effects of dietary fatty acid compositions on glucose metabolism, large yellow croaker juveniles Larimichthys crocea (initial weight, 36.80 ± 0.39 g) were fed with two experiment diets for 12 weeks. The two diets contained 6.5% of fish oil (FO) and palm oil (PO), respectively. Results showed that the contents of saturated fatty acids in liver and muscle, levels of glucose, triglyceride (TG), non-esterified fatty acid (NEFA), and leptin in blood were significantly higher in PO group, while the hepatic glycogen and muscle glycogen significantly decreased (P < 0.05). There were no significant differences in blood insulin and adiponectin levels between the two groups (P > 0.05). Compared with the FO group, the expressions of glucokinase (GK), glucose-6-phosphate dehydrogenase, glycogen synthase (GYS), glucose transporter 2 (GLUT2), insulin receptor 1 (IR1), insulin receptor substrate 1 (IRS1), insulin receptor substrate (IRS2), and protein kinase B (AKT2) were significantly decreased, and the expressions of phosphoenolpyruvate carboxykinase (PEPCK) in liver were significantly increased in the PO group. Meanwhile, the expressions of GK, phosphofructokinase, GYS, GLUT4, and insulin receptor 2 (IR2) were significantly reduced, and the expressions PEPCK, fructose-1 and 6-diphosphatase in muscle were significantly increased in the PO group. In conclusion, palm oil in diet could inhibit the utilization of glucose and promote the endogenous glucose production in large yellow croaker by reducing the sensitivity of insulin, so as to increase the blood glucose level.

Collagen peptide modified carboxymethyl cellulose as both antioxidant drug and carrier for drug delivery against retinal ischaemia/reperfusion injury.

Oxidative stress can cause injury in retinal endothelial cells. Carboxymethyl cellulose modified with collagen peptide (CMCC) is of a distinct antioxidant capacity and potentially a good drug carrier. In this study, the protective effects of CMCC against H2 O2 -induced injury of primary retinal endothelial cells were investigated. In vitro, we demonstrated that CMCC significantly promoted viability of H2 O2 -treated cells, efficiently restrained cellular reactive oxygen species (ROS) production and cell apoptosis. Then, the CMCC was employed as both drug and anti-inflammatory drug carrier for treatment of retinal ischaemia/reperfusion (I/R) in rats. Animals were treated with CMCC or interleukin-10-loaded CMCC (IL-10@CMCC), respectively. In comparisons, the IL-10@CMCC treatment exhibited superior therapeutic effects, including better restoration of retinal structural thickness and less retinal apoptosis. Also, chemiluminescence demonstrated that transplantation of IL-10@CMCC markedly reduced the retinal oxidative stress level compared with CMCC alone and potently recovered the activities of typical antioxidant enzymes, SOD and CAT. Therefore, it could be concluded that CMCC provides a promising platform to enhance the drug-based therapy for I/R-related retinal injury.

Histidine protects human lens epithelial cells against H2 O2 -induced oxidative stress injury through the NF-кB pathway.

Histidine, an amino acid that is essential to humans, exerts favorable cytoprotective effects against oxidative stress in vivo and in vitro, but the effect of histidine on human lens epithelial cells (HLECs) and its regulatory mechanism have not previously been reported. The oxidative stress induced by H2 O2 plays an important role in the pathology of cataract. We know that HLECs are important for maintaining the transparency and integrity of the lens. In the present study, we investigated the possible molecular mechanisms underlying the cytoprotective effects of histidine against H2 O2 -induced oxidative stress in HLECs. The results showed that histidine reduced H2 O2 -induced cell apoptosis and reactive oxygen species (ROS) accumulation, protected HLECs from H2 O2 -induced oxidative damage, increased the expression levels of dismutase (SOD) and glutathione (GSH), and decreased the expression level of malondialdehyde (MDA), and the protective effect of histidine depended on the NF-кB pathway. Together, these data suggest that histidine could be helpful in inhibiting oxidative stress in the lens and thus attenuating cataract formation.

High level of dietary soybean oil depresses the growth and anti-oxidative capacity and induces inflammatory response in large yellow croaker Larimichthys crocea.

Increasing demand, uncertain availability and high price of fish oil with the expansion of aquaculture made it essential to search alternative lipid sources. Vegetable oil has been proved to be the best candidate for the replacement of fish oil in aquafeeds. However, this replacement especially in high level potentially has some negative effects on fish. The present study was conducted to investigate the growth performance, anti-oxidative and inflammatory responses of large yellow croaker to replacement of dietary fish oil by soybean oil. Three isonitrogenous (46% crude protein) and isolipidic (13% crude lipids) diets were formulated to feed fish (initial body weight: 36.80 ±â€¯0.39 g) for 12 weeks. The control diet was designed to contain 6.5% of fish oil, and named as FO. On the basis of the control diet, the fish oil was 50% and 100% replaced by soybean oil, and these two diets were named as FS and SO, respectively. Results showed that the specific growth rate significantly decreased in the SO group. Crude lipid contents in muscle and liver of fish fed SO diet were significantly higher than those in the FO group. The ratio of n-3 poly-unsaturated fatty acids (PUFAs) to identified fatty acids in liver decreased significantly, while n-6 PUFAs increased significantly with increasing dietary soybean oil inclusion. The levels of triacylglycerol, non-esterified fatty acid and tumour necrosis factor α, and the activity of aspartate aminotransferase in serum significantly increased in SO group. The total anti-oxidative capacity and expressions of the anti-oxidation-related genes (superoxide dismutase 1 and 2, catalase, glutathion peroxidase and nuclear factor erythroid 2-related factor 2) were significantly decreased by dietary soybean inclusion. Dietary soybean oil significantly decreased the gene expressions of the anti-inflammatory cytokines (arginase I and interleukin 10), and increased the pro-inflammatory cytokines (tumour necrosis factor α and interleukin 1ß). The replacement of dietary fish oil by soybean oil also induced an over-expression of toll-like receptor 22 and myeloid differentiation factor 88 in liver. In conclusion, dietary soybean oil could suppress growth performance and liver anti-oxidative capacity, and induce inflammatory responses of large yellow croaker.

Exothermic or Endothermic Decomposition of Disubstituted Tetrazoles Tuned by Substitution Fashion and Substituents.

Nitrogen-rich compounds such as tetrazoles are widely used as candidates in gas-generating agents. However, the details of the differentiation of the two isomers of disubstituted tetrazoles are rarely studied, which is very important information for designing advanced materials based on tetrazoles. In this article, pairs of 2,5- and 1,5-disubstituted tetrazoles were carefully designed and prepared for study on their thermal decomposition behavior. Also, the substitution fashion of 2,5- and 1,5- and the substituents at C-5 position were found to affect the endothermic or exothermic properties. This is for the first time to the best of our knowledge that the thermal decomposition properties of different tetrazoles could be tuned by substitution ways and substitute groups, which could be used as a useful platform to design advanced materials for temperature-dependent rockets. The aza-Claisen rearrangement was proposed to understand the endothermic decomposition behavior.

Genetic and Antibiotic Resistance Characteristics of Campylobacter jejuni Isolated from Diarrheal Patients, Poultry and Cattle in Shenzhen.

OBJECTIVE: To investigate genetic and antibiotic resistance characteristics of Campylobacter jejuni (C. jejuni) isolated from Shenzhen. METHODS: Multilocs sequence typing and agar dilution methods were used to define the genotype and antibiotic resistance of C. jejuni, respectively. RESULTS: In total, 126 C. jejuni strains were isolated. The prevalence of C. jejuni was 5.3% in diarrheal patients. The prevalence in poultry meat (36.5%) was higher than that in cattle meat (1.1%). However, the prevalence in poultry cloacal swabs (27.0%) was lower than that in cattle stool (57.3%). Sixty-two sequence types were obtained, among which 27 of the STs and 10 alleles were previously unreported. The most frequently observed clonal complexes were ST 21 (11.9%), ST-22 (10.3%), and ST-403 (7.1%). ST-21, ST-45, ST-354, ST-403, and ST-443 complexes overlapped between isolates from patients and cattle, whereas ST-45 and ST-574 complexes overlapped between isolates from patients and poultry. All C. jejuni were resistant to at least one antibiotic. The highest resistance rate was toward ciprofloxacin (89.7%), followed by tetracycline (74.6%), and nalidixic acid (69.0%). CONCLUSION: This is the first report of the genotypes and antibiotic resistance of C. jejuni in Shenzhen. Overlapping clonal complexes were found between isolates from patients and cattle, and between patients and poultry.

[Density Functional Theory Calculation and Raman Spectroscopy Studies of Organophosphorus Pesticides].

Organophosphorus pesticides were often used for prevention and control disease and insect of plant, and are acute toxic to human and livestock by anti-ache activity. The molecular geometry of three organophosphorus pesticides(dimethoate, trichlorfon and phosalone) were constructed on Gauss View3.07, and Density functional theory (DFT) was used to optimize and calculate the vibrational wavenumbers of three organophosphorus pesticides by B3LYP hybrid functional and 6-31G(d, p) basis set. The experimental spectra of three organophosphorus pesticides were compared with the theoretically calculated spectra and Surface-enhanced Raman Scattering spectra (SERS). The results indicated that the experimental spectra and theoretically calculated spectra of three organophosphorus pesticides have a very good match. The Raman peaks of three organophosphorus pesticides were roundly assigned between the range of 400～1 800 cm(-1), and the characteristics peaks of three organophosphorus pesticides were found. The Raman vibration peak of organophosphorus pesticide may appear similar characteristic peak. The pesticide contained PO is between 1 140 and 1 320 cm(-1), the pesticide contained PS is in the range 535～750 cm(-1), and the organophosphorus pesticide contained P­O­C is n the range 920～1 088 cm-1. The different characteristic peaks of three pesticides were found by the contrast of the surface enhanced Raman spectra. This shows that the SERS method can be used to identify the organophosphorus pesticide. The results can furnish a theoretical support for qualitative and quantitative analysis of organophosphorus pesticide.

Density Functional Theory Calculation and Raman Spectroscopy Studies of Carbamate Pesticides.

In order to obtain the molecular structure vibration information of carbamate pesticide, three carbamate pesticides (carbaryl, carbofuran and aldicarb) were optimized and calculated with B3LYP hybrid functional and 6-31G(d,p) basis set, and their experimental spectra were collected with the Raman spectrometer. The theoretically calculated spectra were compared with the experimental spectra carefully. The results indicated that the theoretically calculated spectra have a very good match with the experimental spectra. The vibrational peaks of three carbamate pesticides were assigned between the range of 400～3 200 cm-1, and the characteristic peaks of carbamate pesticide were found at 874, 1 014, 1 162 and 1 716 cm-1. The characteristic peaks of three carbamate pesticides were found by the contrast of the experimental spectra. The results can provide a theoretical basis for the detection of carbamate pesticide, and will be applied to the identification of carbamate pesticide residues in agricultural products.

[Model Optimization of Ternary System Adulteration Detection in Camellia Oil Based on Visible/Near Infrared Spectroscopy].

Visible/near infrared spectroscopy combined with chemometrics methods was used to detect ternary system adulteration in camellia oil quantificationally. In order to get adulterated samples, rapeseed oil and peanut oil were added to pure camellia oil in different proportion. Visible/near infrared spectroscopy data of pure and adulterated camellia oil samples were acquired in the wavelength range of 350~1800nm, and samples were randomly divided into calibration set and prediction set. The adulteration models were optimized by comparing different wavelength ranges, pretreatment methods and calibration methods The results show that the optimal modeling wavelength ranges and pretreatment methods for the prediction models of rapeseed oil, peanut oil and total adulteration amount are 750~1 770, 900~1 770, 870~1 770 nm and Multiple scattering correction (MSC), Standard normal variate (SNV) and second order differentia, and the best modeling method is Least square support vector machine (LSSVM). The correlation coefficient (R(P)) in prediction set and the root mean square error predictions(RMSEPs) of optimal adulteration models for rapeseed oil, peanut oil and total adulteration are 0.963, 0.982, 0.993 and 2.1%, 1.5%, 1.8%, respectively. Thus it can be seen that visible /near infrared spectroscopy combined with chemometrics methods can be used for quantitative ternary system adulteration detection in camellia oil.

[Quantitative Detection of Iron in Soybean Oils with Laser Induced Breakdown Spectroscopy and Simple Regression Methods].

LIBS (laser-induced breakdown spectroscopy) was used to detect Fe element content in soybean oil quantitatively. In this experiment, a series of soybean oil samples with different concentrations of Fe were used; LIBS spectra were collected with a two-channel high precision spectrometer. According to the LIBS spectrum of samples, two characteristic wavelength of Fe (404.58 and 406.36 nm) were determined, and different simple regression methods (exponential regression, linear regression and quadratic regression) were used to establish the quantitative analysis models of Fe content using each characteristic spectral line. The results indicate that the average relative error of Fe I 404.58 and Fe I 406.36 in simple exponential regression, linear regression and quadratic regression models were 29.49%, 8.93%, 8.70% and 28.95%, 8.63%, 8.44%, respectively. The results of Fe I 406.36 regression models is better than that of Fe I 404.58, and the quadratic regression model is optimal among the three regression models. According to these results, LIBS technology has certain feasibility for detecting Fe in soybean oil; the quadratic linear regression model can improve the prediction accuracy of Fe element effectively.