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To investigate the regulatory effect and possible mechanism of exogenous sodium nitroprusside (SNP) treatment on the pericarp browning of refrigerated ‘Nanguo’ pear fruit, the effect of 1.0 mmol/L SNP pretreatment on the pericarp browning of ‘Nanguo’ pear fruit during shelf life at room temperature after 180 days of refrigerated storage was investigated. The results showed that browning symptoms appeared in the SNP-treated fruit three days later than the control fruit, and at the end of the shelf life, the browning incidence and browning index were 41.8% and 31.9% of those of the control fruit, respectively. The treatment protected the structural integrity of pericarp cells and inhibited the elevation of membrane permeability. Further analysis revealed that at the end of the shelf life, the superoxide anion, hydroxyl and 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH) radical scavenging capacity of the SNP-treated fruit were 1.65, 1.13, and 1.24 times higher than those of the control fruit, respectively. Meanwhile, the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) was significantly reduced, which was 25.2% and 32.8% lower than that of the control group, respectively, and the activities and gene expression of polyphenol oxidase and peroxidase were 17.5%, 28.8%, 37.5% and 39.2% lower than those of the control group, respectively. In addition, the synthesis of phenolics was inhibited to some extent. In conclusion, SNP treatment could alleviate the occurrence of pericarp browning in refrigerated ‘Nanguo’ pear fruit by inhibiting membrane lipid peroxidation and maintaining cellular structural integrity and function.

This study investigated the effect of salicylic acid (SA) treatment on preserving the color and nutritional quality of broccoli during postharvest cold storage. The results demonstrated that SA treatment significantly delayed the yellowing process, increased chlorophyll content, −a*/b* value, quantum yield (Fv/Fm), and fluorescence decline ratio (Rfd) and decreased L* value and yellowing index compared with untreated control. Meanwhile, the losses of glucoraphanin (GRA), glucobrassicin (GBS), sulforaphane (SFN), indole-3-methanol (I3C), and ascorbic acid (AsA) were obviously alleviated in the treated samples, and the accumulation of total phenols and total flavonoids was significantly increased. In addition, the total antioxidant capacity (T-AOC) of the treated samples was improved remarkably and the content of malondialdehyde (MDA) was significantly reduced. Multivariate statistical analysis visualized the distribution of sensory and nutritional variables in both groups of samples, further demonstrating that SA treatment was more effective in preserving GRA and AsA and effectively induced an improvement of the antioxidant capacity.

Complementary product recommendations can provide complementary matching products for the convenience of users. However, existing work using graph neural networks ignores the multimodal information of products, and the performance of multimodal models is affected when the modal information is missing. In addition, existing multimodal models simply concatenate the modalities, ignoring the connections between the modalities. For these reasons, a complementary product recommendation using graph neural network (CPRUG) model is proposed. The model combines the graph neural network with multimodal information to strengthen the product representation. Then, it uses the graph attention network to deal with the multimodal absence problem, maintain the performance of the model, and improve the robustness of the model. Finally, it uses the common attention mechanism and matrix factorized bilinear pooling method to fuse multimodal features and learn the complementary relationship of products. Experiments are conducted on the Amazon dataset, and the experimental results show that the model outperforms other baseline models. [ABSTRACT FROM AUTHOR]

The allyl-substituted cysteine derivatives were major components of sulfur compounds in garlic. This study separated and identified 3 allyl-substituted cysteine derivatives, i.e. S-allyl-L-cysteine (SAC), S-allyl-L-cysteine sulfoxide (ACSO) and γ-L-glutamyl-S-allyl-L-cysteine (GSAC). Furthermore, scavenging ability of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical and iron chelating ability were tested through comparing the compounds of SAC, ACSO and GSAC with glutathione (GSH) to evaluate the antioxidation. SAC, ACSO and GSAC were isolated from garlic bulbs using ion-exchange chromatography and pre-HPLC (high performance liquid chromatography). Their molecular structures were identified by high performance liquid chromatography-electrospray ionization-mass/mass spectrometry (HPLC-ESI-MS/MS), proton nuclear magnetic resonance (1H NMR), carbon-13 nuclear magnetic resonance (13C NMR) and specific rotatory power. SAC and ACSO which yielded the expected [M+H]+ of m/z 162.1 and 177.8 by the measurement of mass spectrometry under positive ion mode were conferred as S-allyl-L-cysteine (C6H11O2NS) and S-allyl-L-cysteine sulfoxide (C6H11O3NS) respectively compared with the data of corresponding standard. GSAC, showing the corresponding [M-H]- of m/z 288.8, was identified as γ-glutamyl-S-allyl-L-cysteine (C11H18O5N2S) by HPLC-MS. The 1H NMR spectrum of SAC and ACSO indicated the presence of the cysteinyl (δ 2.96 and 3.83, 3H) and (δ 3.26 and 4.13, 3H) moieties. The 13C NMR spectrum of compound SAC and ACSO showed the presence of the cysteinyl carboxyl (δ 175.6 and δ 188.0) carbons. Similarly, the 1H NMR spectrum of GSAC indicated the presence of the glutamyl (δ 2.32-2.43, 2.66 and 3.46, 5H) and cysteinyl (δ 2.75 and 4.76, 3H) moieties. The 13C NMR spectrum of GSAC revealed the presence of 11 magnetically nonequivalent carbon atoms, with three of them being the glutamyl carboxyl, glutamyl carbonyl and cysteinyl carboxyl (δ 182.5, 183.2 and 184.4) carbons. Meanwhile, the scavenging activity of DPPH free radical and the chelating activity of iron ion by allyl-substituted sulfides (SAC, ACSO and GSAC) were determined with reference to cysteine derivative of GSH. The scavenging activity of DPPH free radical had no significant difference between GSH (71.14%) and both of SAC (73.55%) and GSAC (72.68%). Iron ion is one of the main oxidizing auxiliaries which can initiate free radical in vitro and vivo, therefore, chelating with iron ion can remove the oxidizing auxiliaries effectively, and prevent the formation of free radicals. Likewise, no significant differences between GSH (81.21%) and both of SAC (79.18%) and ACSO (78.13%) were observed for the chelating activity of iron ion tested in this study. In particular, the chelating activity of iron ion of GSAC (92.76%) was greater than GSH. These results confirmed the antioxidant activity of these allyl-substituted cysteine derivatives. Garlic planting area in China accounted for a third of the world. At harvest time, garlic waste dumping in the field led to the waste of resource and the pollution of the environment, and these waste parts of garlic were also the sources of sulfur compounds. The processing in this experiment could make full use of garlic (edible part and non-edible part), and the study could provide some theoretical guidance for the industrialization of large-scale extraction of sulfur-containing products, and improve the level of deep processing of garlic. The work revealed the first evidence of antioxidant activity of GSAC, which could be involved in its chelating activity of iron ion. [ABSTRACT FROM AUTHOR]

Objective: To assess the value of different kinds of cryptococcal capsular antigen detection methods in diagnosis and efficacy assessment in the patients with cryptococcal meningoencephalitis., Methods: From October 2012 to March 2015, cerebrospinal fluid (CSF) samples were collected from 57 patients withcentral nervous system infection who hospitalized in Sir Run Run Shaw Hospital. The cryptococcal capsular antigen in CSF was detected by Lateral flow assay (LFA), Latex agglutination test(LA) and Enzyme immunoassay (EIA). Follow-up study was achieved in 10 patients by detecting the samples of their CSF using LA and EIA, so that the dynamic changes of the antigen level could be obtained and observed during the treatment., Results: The sensitivity of LFA and LA were both 95%, meanwhile the specificity were both 100%; the sensitivity and specificity of EIA were both 100%. The level of cryptococcal capsular polysaccharide antigen decreased gradually with patients recovering., Conclusions: All the three different methods could beof great importance for the early diagnosis of cryptococcal meningoencephalitis. LFA should be recommended for screening the disease. Follow-up study by detecting the antigen level of CSF is valued in assessing the treatment efficacy of cryptococcal diseases.