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[Display omitted] • Double-sided PDMS-PDMS-PEG leaves were fabricated for seven common leafy greens. • Epicuticular wax prevents wetting and E. coli O157:H7 attachment on leaf surface. • Wax also enhanced the retention of attached E. coli O157:H7 on leaf surface. • E. coli O157:H7 survived and grew on artificial leaves with nutrients supplied. • The artificial leaves behaved similarly to its natural leaves in sanitation. Leafy green surface microbiology studies often experience significant variations in results due to the heterogeneous nature of leaf surfaces. To provide a precise and controllable substitute, we microfabricated double-sided artificial leafy green phylloplanes using polydimethylsiloxane (PDMS) with a vinyl-terminated polyethylene glycol chain-based hydrophobicity modifier (PDMS-PEG) to modify PDMS hydrophobicity. We further tested the properties and applications of these artificial leaves, by examining the function of epicuticular wax, growth and survival of E. coli O157:H7 87–23 on the surface, and removal of attached E. coli cells via sanitation. The double-sided PDMS-PDMS-PEG leaves well-replicated their natural counterparts in macroscopic and microscopic structure, hydrophobicity, and E. coli O157:H7 87–23 attachment. After depositing natural epicuticular wax onto artificial leaves, the leaf surface wetting ability decreased, while E. coli O157:H7 87–23 surface retention increased. The artificial leaves supplied with lettuce lysate or bacterial growth media supported E. coli O157:H7 87–23 growth and survival similarly to those on natural leaves. In the sanitation test, the artificial lettuce leaves also displayed patterns similar to those of natural leaves regarding sanitizer efficiency. Overall, this study showcased the microfabrication and applications of double-sided PDMS-PDMS-PEG leaves as a replicable and controllable platform for future leafy green food safety studies. [ABSTRACT FROM AUTHOR]

Leafy greens, especially lettuce, are repeatedly linked to foodborne outbreaks. This paper studied the susceptibility of different leafy greens to human pathogens. Five commonly consumed leafy greens, including romaine lettuce, green-leaf lettuce, baby spinach, kale, and collard, were selected by their outbreak frequencies. The behavior of E. coli O157:H7 87-23 on intact leaf surfaces and in their lysates was investigated. Bacterial attachment was positively correlated with leaf surface roughness and affected by the epicuticular wax composition. At room temperature, E. coli O157:H7 had the best growth potentials on romaine and green-leaf lettuce surfaces. The bacterial growth was positively correlated with stomata size and affected by epicuticular wax compositions. At 37 °C, E. coli O157:H7 87-23 was largely inhibited by spinach and collard lysates, and it became undetectable in kale lysate after 24 h of incubation. Kale and collard lysates also delayed or partially inhibited the bacterial growth in TSB and lettuce lysate at 37 °C, and they sharply reduced the E. coli O157:H7 population on green leaf lettuce at 4 °C. In summary, the susceptibility of leafy greens to E. coli O157:H7 is determined by a produce-specific combination of physiochemical properties and temperature. • Lysate will not affect E. coli O157:H7 growth and survival on intact leaves. • E. coli 's survival on leaves depends on produce-specific traits and temperature. • Spinach, collard, kale lysates are natural antimicrobials against E. coli O157:H7. • At 37 °C, kale lysate inactivated E. coli O157:H7 in pure culture within 24h. • Kale and collard lysates reduced E. coli population on the lettuce surface at 4 °C. [ABSTRACT FROM AUTHOR]

Abstract: Queen bee larvae (QBL), by‐products of royal jelly processing, was enzymatically hydrolyzed to produce bioactive peptides. Five enzymes were firstly used to obtain hydrolysates which were evaluated for their antioxidative performances. QBL hydrolyzed by pepsin, showing the highest antioxidant resistance, were prepared and isolated by ultrafiltration using different molecular weight cutoffs of <1, 1–5, 5–10, and >10 kDa. Then, hydrolysate III (MW 1–5 kDa) with the highest activity was purified through continuous chromatography. Antioxidant capacities of active peak 3 (P3) to DPPH, hydroxyl, superoxide, ABTS, oxygen radical absorbance capacity radicals assay were 74.31%, 82.44%, 74.53%, 78.81%, and 1,074 μM TE/g, respectively. Finally, the most potent antioxidant hydrolysate was determined through a high‐speed amino acid analyzer. The results of the QBLH for in vitro antioxidant assays have indicated that P3 is a good antioxidative peptide due to its high percentage of hydrophobic amino acids and has vast prospects for future development and application. Practical applications: QBL has been used as a traditional medicine for several millennia in China due to its rich nutrition and potent effect in improving human immunity, however, the utilization of QBL resources industry is rather low. This article evaluated the antioxidant activities of queen bee larvae using DPPH, hydroxyl, superoxide, ABTS, ORAC radicals assay, respectively. This article indicates that high antioxidant amino acid residues can be obtained from QBL through simple processing methods (enzymatic hydrolyzing and membrane isolating). Our study could arouse a great interest among researchers to develop a new series of QBL products with high efficient antioxidant properties. [ABSTRACT FROM AUTHOR]

Sun-drying is a low-cost, low-technology fish preservation method frequently employed in developing areas. However, the process promotes lipid oxidation and its associated undesired flavours and odours. This study investigated low-technology solutions for impact on lipid oxidation and sensory attributes of oven-dried omena fish ( Rastrineobola argentea). Two oven-drying conditions and four doses of clove water extract 'dip' pretreatments were studied in a complete factorial design. Lipid oxidation in dried fish was assessed by TBARS, peroxide value and fatty acid analysis by GC- FID. Results showed that soaking in 10 g L−1 clove water extract for 1 h and oven-drying at 150 °C × 30 min significantly reduced TBARS and peroxide values in omena fish by 77% and 79%, respectively, and polyene index showed improved retention of long-chain polyunsaturated fats, compared to original drying condition. Lastly, panellists of a triangle test were able to discriminate between biscuits made with the modified and original dried fish. [ABSTRACT FROM AUTHOR]

Sprouts and microgreens present unique food safety risks. This study aimed to enhance microbial food safety of sprouts and microgreens via seed sanitation and antimicrobial spray. Radish, broccoli, and kale seeds inoculated with Escherichia coli O157:H7 were sanitized by a high acoustic power density (APD) ultrasound and mild heat (55 °C water) combined treatment for 5 min (US-5) or 10 min (US-10) that was compared with the FDA-recommended 20 min, 20,000 mg/L chlorine treatment. E. coli O157:H7 populations of the seeds and sprouts/microgreens were enumerated immediately after seed sanitation, on day-4 of germination, and after 4 more days in storage, or at the time of harvesting (day 7) for microgreens. Sanitated seeds were planted into germination mix and sprayed with water, 0.1% or 0.2% of calcium oxide (CaO) solution three times a day for 7 days. The US-5 treatment achieved a comparable E. coli O157:H7 reduction and sprout yield as the 20,000 mg/L chlorine treatment. The US-10 treatment exhibited a significantly higher E. coli O157: H7 reduction in all three seed types than the chlorine treatment but with a lower germination rate (p < 0.05). The 0.1% CaO spray effectively inhibited E. coli O157:H7 growth in kale microgreens while maintaining the yield and germination rate. For the same varieties of seeds regardless of treatment, microgreens harvested without roots showed much lower microbial loads (3.0–3.9 log CFU/g) than sprouts (6.0–7.0 log CFU/g) with roots. Overall, the US-5 treatment can be an adequate and environmentally friendly alternative to the traditional chlorine treatment. This study provided a practical solution to ensure microbial safety of the sprouts and presented evidence that microgreens are generally safer than sprouts. • High acoustic power density (APD) ultrasound is effective for surface sanitation. • High APD ultrasound +55 °C water seed sanitation can replace the 20,000-ppm chlorine method. • Seed sanitation efficiency is negatively correlated with seed surface roughness. • Microgreens have lower E. coli concentration in edible parts than sprouts. • Broccoli seed skin was damaged the most during pre-germination treatments. [ABSTRACT FROM AUTHOR]

The massive worldwide spread of the SARS-CoV-2 virus is fueling the COVID-19 pandemic. Since the first whole-genome sequence was published in January 2020, a growing database of tens of thousands of viral genomes has been constructed. This offers opportunities to study pathways of molecular change in the expanding viral population that can help identify molecular culprits of virulence and virus spread. Here we investigate the genomic accumulation of mutations at various time points of the early pandemic to identify changes in mutationally highly active genomic regions that are occurring worldwide. We used the Wuhan NC_045512.2 sequence as a reference and sampled 15 342 indexed sequences from GISAID, translating them into proteins and grouping them by month of deposition. The per-position amino acid frequencies and Shannon entropies of the coding sequences were calculated for each month, and a map of intrinsic disorder regions and binding sites was generated. The analysis revealed dominant variants, most of which were located in loop regions and on the surface of the proteins. Mutation entropy decreased between March and April of 2020 after steady increases at several sites, including the D614G mutation site of the spike (S) protein that was previously found associated with higher case fatality rates and at sites of the NSP12 polymerase and the NSP13 helicase proteins. Notable expanding mutations include R203K and G204R of the nucleocapsid (N) protein inter-domain linker region and G251V of the viroporin encoded by ORF3a between March and April. The regions spanning these mutations exhibited significant intrinsic disorder, which was enhanced and decreased by the N-protein and viroporin 3a protein mutations, respectively. These results predict an ongoing mutational shift from the spike and replication complex to other regions, especially to encoded molecules known to represent major β-interferon antagonists. The study provides valuable information for therapeutics and vaccine design, as well as insight into mutation tendencies that could facilitate preventive control. [ABSTRACT FROM AUTHOR]

The massive worldwide spread of the SARS-CoV-2 virus is fueling the COVID-19 pandemic. Since the first whole-genome sequence was published in January 2020, a growing database of tens of thousands of viral genomes has been constructed. This offers opportunities to study pathways of molecular change in the expanding viral population that can help identify molecular culprits of virulence and virus spread. Here we investigate the genomic accumulation of mutations at various time points of the early pandemic to identify changes in mutationally highly active genomic regions that are occurring worldwide. We used the Wuhan NC_045512.2 sequence as a reference and sampled 15 342 indexed sequences from GISAID, translating them into proteins and grouping them by month of deposition. The per-position amino acid frequencies and Shannon entropies of the coding sequences were calculated for each month, and a map of intrinsic disorder regions and binding sites was generated. The analysis revealed dominant variants, most of which were located in loop regions and on the surface of the proteins. Mutation entropy decreased between March and April of 2020 after steady increases at several sites, including the D614G mutation site of the spike (S) protein that was previously found associated with higher case fatality rates and at sites of the NSP12 polymerase and the NSP13 helicase proteins. Notable expanding mutations include R203K and G204R of the nucleocapsid (N) protein inter-domain linker region and G251V of the viroporin encoded by ORF3a between March and April. The regions spanning these mutations exhibited significant intrinsic disorder, which was enhanced and decreased by the N-protein and viroporin 3a protein mutations, respectively. These results predict an ongoing mutational shift from the spike and replication complex to other regions, especially to encoded molecules known to represent major β-interferon antagonists. The study provides valuable information for therapeutics and vaccine design, as well as insight into mutation tendencies that could facilitate preventive control. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to evaluate the feasibility of clinicopathological characteristics and computed tomography (CT) morphological features in predicting lymph node metastasis (LNM) for patients with T1 colorectal cancer (CRC). Methods: A total of 144 patients with T1 CRC who underwent CT scans and surgical resection were retrospectively included in our study. The clinicopathological characteristics and CT morphological features were assessed by two observers. Univariate and multiple logistic regression analyses were used to identify significant LNM predictive variables. Then a model was developed using the independent predictive factors. The predictive model was subjected to bootstrapping validation (1000 bootstrap resamples) to calculate the calibration curve and relative C-index. Results: LNM were found in 30/144 patients (20.83%). Four independent risk factors were determined in the multiple logistic regression analysis, including presence of necrosis (adjusted odds ratio [OR] = 10.32, 95% confidence interval [CI] 1.96–54.3, p = 0.004), irregular outer border (adjusted OR = 5.94, 95% CI 1.39–25.45, p = 0.035), and heterogeneity enhancement (adjusted OR = 7.35, 95% CI 3.11–17.38, p = 0.007), as well as tumor location (adjusted ORright-sided colon = 0.05 [0.01–0.60], p = 0.018; adjusted ORrectum = 0.22 [0.06–0.83], p = 0.026). In the internal validation cohort, the model showed good calibration and good discrimination with a C-index of 0.89. Conclusions: There are significant associations between lymphatic metastasis status and tumor location as well as CT morphologic features in T1 CRC, which could help the doctor make decisions for additional surgery after endoscopic resection. Key Points: • LNM more frequently occurs in left-sided T1 colon cancer than in right-sided T1 colon and rectal cancer. • CT morphologic features are risk factors for LNM of T1 CRC, which may be related to fundamental biological behaviors. • The combination of tumor location and CT morphologic features can more effectively assist in predicting LNM in patients with T1 CRC, and decrease the rate of unnecessary extra surgeries after endoscopic resection. [ABSTRACT FROM AUTHOR]

Red rice ( Oryza sativa L.) that has a red (reddish brown) bran layer in de-hulled rice is known to contain rich biofunctional components. Germination is an effective technique to improve the nutritional quality, digestibility, and flavor of de-hulled rice. Ultrasonication, a form of physical stimulation, has been documented as a novel approach to improve the nutritional quality of plant-based food. This study was undertaken to test the use of ultrasound to enhance the nutritional value of red rice. Ultrasonication (5 min, 16 W/L) was applied to rice during soaking or after 66 h germination. Changes of metabolites (amino acids, sugars, and organic acids) in red rice treated by ultrasonication were determined using a GC/MS plant primary metabolomics analysis platform. Differential expressed metabolites were identified through multivariate statistical analysis. Results showed that γ-aminobutyric acid (GABA) and riboflavin (vitamin B 2 ) in red rice significantly increased after germination for 72 h, and then experienced a further increase after treatment by ultrasound at different stages during germination. The metabolomics analysis showed that some plant metabolites, i.e. GABA, O-phosphoethanolamine, and glucose-6-phosphate were significantly increased after the ultrasonic treatment (VIP > 1.5) in comparison with the untreated germinated rice. The findings of this study showed that controlled germination with ultrasonic stress is an effective method to enhance GABA and other health-promoted components in de-hulled rice. [ABSTRACT FROM AUTHOR]

Although vaccines play a major role in the prevention of infectious bronchitis (IB), Anti-IB drugs still have great potential in poultry production. Radix Isatidis polysaccharide (RIP) is a crude extract of Banlangen with antioxidant, antibacterial, antiviral, and multiple immunomodulatory functions. The aim of this study was to explore the innate immune mechanisms responsible for RIP-mediated alleviation of infectious bronchitis virus (IBV)-induced kidney lesions in chickens. Specific-pathogen-free (SPF) chicken and chicken embryo kidney (CEK) cells cultures were pretreated with RIP and then infected with the QX-type IBV strain, Sczy3. Morbidity, mortality, and tissue mean lesion scores were calculated for IBV-infected chickens, and the viral loads, inflammatory factor gene mRNA expression levels, and innate immune pathway gene mRNA expression levels in infected chickens and CEK cell cultures were determined. The results show that RIP could alleviate IBV-induced kidney damage, decrease CEK cells susceptibility to IBV infection, and reduce viral loads. Additionally, RIP reduced the mRNA expression levels of the inflammatory factors IL-6, IL-8, and IL-1β by decreasing the mRNA expression level of NF-κB. Conversely, the expression levels of MDA5, TLR3, STING, Myd88, IRF7, and IFN-β were increased, indicating that RIP conferred resistance to QX-type IBV infection via the MDA5, TLR3, IRF7 signaling pathway. These results provide a reference for both further research into the antiviral mechanisms of RIP and the development of preventative and therapeutic drugs for IB. [ABSTRACT FROM AUTHOR]

Contaminated leafy vegetables have been associated with high-profile outbreaks causing severe illnesses. A good understanding of the interactions between human pathogen and produce is important for developing improved food safety control strategies. Currently, the role played by produce surface physiochemical characteristics in such interactions is not well-understood. This work was performed to examine the effects of produce physiochemical characteristics, including surface roughness, epicuticular wax composition, and produce and bacteria surface hydrophobicity on attachment and removal of vegetative bacteria. Escherichia coli K12 was used as a model microorganism to evaluate attachment to and removal from five leafy green vegetables after washing with selected sanitizers. A detailed epicuticular wax component analysis was conducted and the changes of wax composition after sanitation were also evaluated. The results showed that E. coli K12 removal is positively correlated with alkanes, ketones, and total wax content on leaf surfaces. Vegetables with high surface wax content had less rough leaf surfaces and more bacterial removal than the low wax produce. Produce surface roughness positively correlated to E. coli K12 adhesion and negatively correlated to removal. The cells preferentially attached to cut vegetable surfaces, with up to 1.49 times more attachment than on leaf adaxial surfaces. • E. coli K-12 attachment and removal are mediated by physiochemical properties of leaf surfaces. • Bacterial removal is positively correlated with alkanes, ketones, and total wax content on leaf surfaces. • High surface wax vegetables have less rough leaf surfaces and more bacterial removal than the low wax produce. • Produce surface roughness positively correlates to bacterial adhesion and negatively correlates to removal. • E. coli K-12 cells preferentially attach to cut surfaces, with up to 1.49 times more attachment than to leaf adaxial surfaces. [ABSTRACT FROM AUTHOR]

Limited data are published regarding changes in the physicochemical properties of rice flours from germinated de-hulled rice treated by ultrasound. This work was undertaken to evaluate the effect of ultrasound treatment (25 kHz, 16 W/L, 5 min) on starch hydrolysis and functional properties of rice flours produced from ultrasound-treated red rice and brown rice germinated for up to 36 h. Environmental Scanning Electron Microscopy (ESEM) microimages showed that the ultrasound treatment altered the surface microstructure of rice, which helped to improve moisture transfer during steam-cooking. The flours from sonicated germinated de-hulled rice exhibited significantly ( p  < .05) enhanced starch hydrolysis, increased the glucose content, and decreased falling number values and viscosities determined by a Rapid Visco Analyzer. The amylase activity of the germinating red rice and brown rice displayed different sensitivity to ultrasonic treatment. The ultrasonic pre-treatment resulted in a significant reduction in energy use during germination with a potential to further reduce energy use in germinated rice cooking process. The present study indicated that ultrasound could be a low-power consumption method to modify the rheological behavior of germinated rice flour, as well as an efficient approach to improve the texture, flavor, and nutrient properties of steam-cooked germinated rice. [ABSTRACT FROM AUTHOR]