Natural aromatic extract of black tea improved the water retention of pork meat batter.

The effect of varying proportions (w/w) of natural aromatic extract of black tea (NAEBT) with pre-emulsification on the water-holding capacity (WHC) of pork meat batter was investigated. The addition of NAEBT significantly reduced the cooking loss (CL) of pork meat batter from 23.95 % to 18.30 % (P < 0.05). Furthermore, NAEBT with pre-emulsification significantly improved the color stability and increased the springiness (P < 0.05). The results of TBARS and carbonyls indicated that NAEBT with pre-emulsification significantly alleviated oxidative damage to proteins (P < 0.05), resulting in an increased level of ß-sheet (P < 0.05), as confirmed by FT-IR analysis. As a result, the water mobility of pork meat batter was restricted (P < 0.05), resulting in an increase in the energy storage modulus (P < 0.05) and a decrease in the pore size. In summary, the WHC of pork meat batter was improved by the antioxidant effect of the NAEBT.

First Report of Green Mould on Leaf of Phaseolus vulgaris Caused by Cladosporium tenuissimum in Liaoning, China.

Phaseolus vulgaris Linn. is a widely cultivated vegetable throughout the world. From spring 2019 to 2022, green mould symptoms were observed on leaves of P. vulgaris in the greenhouse in Liaoning, China, with disease incidence of 8-75% (plants) and 6-23% (leaves). Symptoms appeared as chlorotic lesions covered with dark green mould. The infections started at the apex or margin of the leaves and then spread inward with a characteristic "V" shape. Lesions exhibited curly morphology. 15 leaf samples with typical symptoms were collected from 5 different greenhouses. A total of 75 (5 replicates of each sample) leaf tissues (0.5 cm × 0.5 cm) were selected from the boundary between diseased and healthy parts. These samples were surface sterilized in 0.5% NaClO formin, rinsed 3 times in sterile distilled water and subsequently incubated at 28℃ on potato dextrose agar (PDA) supplemented with streptomycin (50 µg/ml). Numerous morphologically uniform colonies had been purified, with no other fungi observed. Afterwards, the strains were subcultured on malt extract agar (MEA). Colonies on MEA reached 70 to 80 mm diam after 14 days, smoke-grey to pale olivaceous-grey, woolly, sometimes radially wrinkled. The mycelia were pale olivaceous-grey, with hyphae measuring 1-5 µm wide (n = 20). The conidiophores were solitary or in groups of 2 to 5, and measured 50-280(-350) × 2.5-4 µm (n = 20), with 2-7 septa. The conidiogenous cells exhibited a cylindrical-oblong morphology and measured 10-44 × 5 µm (n = 20), with 0-2 septa, and the loci frequently thickened. The conidia were catenate in densely branched chains, ellipsoid to obovoid, smooth, and measured 2.5-5 × 2-3 µm (n = 50), with 0-4 septa. The morphological characteristics were similar to Cladosporium tenuissimum (Zhang 2003). The representative isolate KZ-19 was selected for molecular identification. The rDNA-ITS, translation elongation factor 1-α and actin genes were amplified, sequenced, and the resulting sequence data were submitted to GenBank (ITS: OQ931048; EF-1α: OQ954495; ACT: OQ954496). The BLAST results exhibited a 99 to 100% similarity with the sequences of C. tenuissimum type strain CBS 125995(ITS: HM148197; EF-1α: HM148442; ACT: HM148687). Furthermore, a multi-locus phylogenetic tree was constructed using the PhyloSuite (v 1. 2. 2) software, which revealed that the strains were most closely related to C. tenuissimum (Zhang et al. 2020). Based on both morphological and molecular characteristics, KZ-19 was finally identified as C. tenuissimum (Bensch 2012). Pathogenicity testing was performed on healthy 1-month-old P. vulgaris plants by inoculating the spore suspension (1×106 conidia/ml) of KZ-19 onto leaf surfaces, while control plants were simulated inoculated with sterile water, and five pots were used for each treatment. The test was performed under field conditions of 16-28°C (temperature) and 24-56% (relative humidity). Chlorotic lesions became evident within 2 days of inoculation, followed by the appearance of green mold on leaves after 7 days. No symptoms were observed in the control group. To fulfill Koch's postulates, the pathogen was re-isolated from three inoculated leaves. The morphological identification of re-isolated pathogens was similar to that of originally isolated pathogens. No infection was observed in non-inoculated control. To the best of our knowledge, this is the first report of C. tenuissimum causing green mould on P. vulgaris. As a ubiquitous saprobic hyphomycete, C. tenuissimum has been implicated in leaf mold in Punica granatum and Trifolium repens, larch bud blight, and strawberry blossom blight in previous years (He et al. 1987; Zhang et al. 2003; Zheng et al. 2010; Nam et al. 2015), presenting a potential threat to numerous crops. Therefore, an investigation of its distribution and pathogenic potential is essential in addition to the development of effective disease management strategies.

Effects of Different Continuous Cropping Years on Bacterial Community and Diversity of Cucumber Rhizosphere Soil in Solar-Greenhouse.

The rhizosphere soils from 1, 3, 5, and 7 years of cucumber continuous cropping in solar-greenhouse were used as the research objects. The region of bacterial 16S rRNA was analyzed by Illumina MiSeq high-throughput sequencing technology. The effect of continuous cropping years on the microbial community structure and diversity in cucumber soil in the greenhouse was investigated. The physical and chemical properties of soil and the activities of urease and catalase were determined. The results showed that cucumber crop succession for different years affected the community composition of the bacteria at the phylum level, and the abundance of Proteobacteria, Chloroflexi, Gemmatimonadetes, Patescibacteria and Firmicutes gradually increased, while Actinobacteria in the soil significantly decreased. Among the top 15 significantly different genera, with the extension of successive years, the relative abundance of most genera in bacteria decreased after a small increase in year 3. The diversity results indicated that soil samples from continuous cropping for 7 years had the lowest community diversity. PICRUSt analysis showed a decreasing trend in soil bacterial function as the cucumber crop succession age increased. In environmental factor clustering analysis, the soil bacterial community was significantly correlated with pH, available nitrogen (AN), soil urease (SUR) and available phosphorus (AP), and the effect on the bacterial community was expressed as SUR > AP > AN > pH.

Effects of propofol, dexmedetomidine, and midazolam on postoperative cognitive dysfunction in elderly patients: a randomized controlled preliminary trial.

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a serious complication after surgery, especially in elderly patients. The anesthesia technique is a potentially modifiable risk factor for POCD. This study assessed the effects of dexmedetomidine, propofol or midazolam sedation on POCD in elderly patients who underwent hip or knee replacement under spinal anesthesia. METHODS: The present study was a prospective randomized controlled preliminary trial. From July 2013 and December 2014, a total of 164 patients aged 65 years or older who underwent hip or knee arthroplasty at China-Japan Friendship Hospital and 41 non-surgical controls were included in this study. Patients were randomized in a 1:1:1 ratio to 3 sedative groups. All the patients received combined spinal-epidural anesthesia (CSEA) with midazolam, dexmedetomidine or propofol sedation. The sedative dose was adjusted to achieve light sedation (bispectral index[BIS] score between 70 and 85). All study participants and controls completed a battery of 5 neuropsychological tests before and 7 days after surgery. One year postoperatively, the patients and controls were interviewed over the telephone using the Montreal cognitive assessment 5-minute protocol. RESULTS: In all, 60 of 164 patients (36.6%) were diagnosed with POCD 7 days postoperatively, POCD incidence in propofol group was significantly lower than that in dexmedetomidine and midazolam groups (18.2% vs. 40.0%, 51.9%, χ = 6.342 and 13.603, P = 0.012 and < 0.001). When the patients were re-tested 1 year postoperatively, the incidence of POCD was not significantly different among the 3 groups (14.0%, 10.6% vs. 14.9%, χ = 0.016 and 0.382, P = 0.899 and 0.536). CONCLUSION: Among dexmedetomidine, propofol and midazolam sedation in elderly patients, propofol sedation shows a significant advantage in term of short-term POCD incidence.

Volatile organic compounds (VOCs) source profiles of on-road vehicle emissions in China.

Volatile Organic Compounds (VOCs) source profiles of on-road vehicles were widely studied as their critical roles in VOCs source apportionment and abatement measures in megacities. Studies of VOCs source profiles from on-road motor vehicles from 2001 to 2016 were summarized in this study, with a focus on the comparisons among different studies and the potential impact of different factors. Generally, non-methane hydrocarbons dominated the source profile of on-road vehicle emissions. Carbonyls, potential important components of vehicle emission, were seldom considered in VOCs emissions of vehicles in the past and should be paid more attention to in further study. VOCs source profiles showed some variations among different studies, and 6 factors were extracted and studied due to their impact to VOCs source profile of on-road vehicles. Vehicle types, being dependent on engine types, and fuel types were two dominant factors impacting VOCs sources profiles of vehicles. In comparison, impacts of ignitions, driving conditions and accumulated mileage were mainly due to their influence on the combustion efficiency. An opening and interactive database of VOCs from vehicle emissions was critically essential in future, and mechanisms of sharing and inputting relative research results should be formed to encourage researchers join the database establishment. Correspondingly, detailed quality assurance and quality control procedures were also very important, which included the information of test vehicles and test methods as detailed as possible. Based on the community above, a better uncertainty analysis could be carried out for the VOCs emissions profiles, which was critically important to understand the VOCs emission characteristics of the vehicle emissions.

Separation and identification of zinc-chelating peptides from sesame protein hydrolysate using IMAC-Zn²âº and LC-MS/MS.

The metal chelating peptides from sesame protein hydrolysates (SPH), treated by papain, alcalase and trypsin, respectively, were investigated. The hydrolysates treated by trypsin had the highest metal chelating ability. The metal chelating peptides were isolated from the trypsin hydrolysates using immobilized metal affinity chromatography (IMAC-Zn(2+)). Further, six zinc-chelating peptides were identified with reversed phase (RP)-HPLC and mass spectrometry (LC-MS/MS). Three of these metal-chelating peptides, Ser-Met, Leu-Ala-Asn and Asn-Cys-Ser, were synthesized and the metal-chelating ability of peptides was measured. The Asn-Cys-Ser peptide showed the highest zinc and iron chelating ability, which was even higher than reduced glutathione (GSH). The results confirm that the zinc or iron chelating activity of these peptides, and provide further support to its feasibility as natural metal chelating agents from sesame protein.

Amino acid composition and antioxidant activities of hydrolysates and peptide fractions from porcine collagen.

The amino acid composition and antioxidant activities of different hydrolysates from porcine collagen were analyzed. The gelatin was hydrolyzed for antioxidative peptides with various proteases, namely papain, protease from bovine pancreas, protease from Streptomyces, and cocktail mixture of protease from bovine pancreas and protease from Streptomyces. The hydrolysates were assessed using methods of DPPH radical-scavenging ability, metal-chelating ability and lipid peroxidation inhibition activity. It was found that the collagen hydrolysates by different protease treatments had different amino acid compositions and antioxidant properties. However, the contents of Hyp and Pro were improved and the content of Gly was decreased in each collagen hydrolysate compared with collagen. The hydrolysate prepared with the cocktail mixture of proteases, which exhibited the highest antioxidant activity, was separated into 6 fractions by gel filtration chromatography. Fraction 2 was further separated by ion exchange chromatography. Fraction 2b with abundant basic amino acids and Fraction 2d which was slightly acidic fractions had higher radical-scavenging and metal-chelating activities, and both Fraction 2b and 2d contained more hydrophobic amino acids. The results confirmed that the antioxidative peptides were rich in Hyp, Pro and Gly, which accounted for half of amino acid composition. This article added further support to the preparation of natural antioxidative peptides from porcine skin collagen.

Distribution, sources and ecological risks of polycyclic aromatic hydrocarbons in an urban landscape river.

The contents of 16 priority water-borne polycyclic aromatic hydrocarbons (PAHs) in water, potential external pollution sources and sediment from the famous landscape of the Qinghuai River were measured by gas chromatography-mass spectrometry (GC-MS). The distribution, composition, source and ecological risk of PAHs were analyzed. The following results were obtained: (1) Benzo[a]pyrene and benzo[ghi] perylene were not detected in all samples. The total contents of 16 priority PAHs (PAH16) varied from 52.5 to 745.3 ng l(-1) with the average of 174.0 ng l(-1) in water, from 96.0 to 1,064.6 ng l(-1) with the average of 329.2 ng l(-1) in potential sources, from 931.7 to 15,295.5 ng g(-1) with the average of 7,133.6 ng g(-1) in sediments. (2) The concentration of PAH16 in water is lower than in sediment and higher rings are more easily detected in sediment. The percentage of higher ring (four- to six-rings) PAHs accounted for more than 55.6% of PAHs in sediment. (3) The value of FLA/(FLA+Pyr) was higher than 0.5 at most sampling points which illustrated the source was related with petrogenic such as liquid fossil fuel combustion. (4) The potential ecosystem risk of low ring PAH for upstream conflux of external Qinhuai River was less than 10%, while it was 10-50% for other sampling points; The four rings PAH shows lower potential ecosystem risk than other ring PAH in this study area; Dibenzo [ah] anthracene (DahA) shows high potential ecosystem risk at all sampling points.

Purification and characterization of a small cationic protein from the tobacco hornworm Manduca sexta.

The prophenoloxidase (proPO) activation system is an important defense mechanism in arthropods, and activation of proPO to active phenoloxidase (PO) involves a serine proteinase cascade. Here, we report the purification and characterization of a small cationic protein CP8 from the tobacco hornworm, Manduca sexta, which can stimulate proPO activation. BLAST search showed that Manduca CP8 is similar to a fungal proteinase inhibitor-1 (AmFPI-1), an inducible serine proteinase inhibitor-1 (ISPI-1), and other small cationic proteins with unknown functions. However, we showed that Manduca CP8 did not inhibit proteinase activity, but stimulated proPO activation in plasma. When small amount (0.1 microg) of purified native CP8 or BSA was added to cell-free plasma samples and incubated for 20 min, low PO activity was observed in both groups. But significantly higher PO activity was observed in the CP8-group than in the BSA-group when more proteins (0.5 microg) were added and incubated for 20 min. However, when the plasma samples were incubated with proteins for 30 min, high PO activity was observed in both the CP8 and BSA groups regardless of the amount of proteins added. Moreover, when PO in the plasma was pre-activated with Micrococcus luteus, addition of CP8 did not have an effect on PO activity, and CP8/bacteria mixture did not stimulate PO activity to a higher level than did BSA/bacteria. These results suggest that CP8 helps activate proPO more rapidly at the initial stage. CP8 mRNA was specifically expressed in fat body and its mRNA level decreased when larvae were injected with saline or bacteria. However, CP8 protein concentration in hemolymph did not change significantly in larvae injected with saline or microorganisms.

A novel ML protein from Manduca sexta may function as a key accessory protein for lipopolysaccharide signaling.

Lipopolysaccharide (LPS) present on the outer membrane of Gram-negative bacteria is one of the most important pathogen-associated molecular patterns and a potent elicitor in innate immunity. In human, TLR4 (Toll-like receptor 4) and MD-2 (myeloid differiation-2) form a receptor complex to transduce the LPS signal into cells. However, in invertebrates, receptors that recognize LPS have not been determined. Here we report the purification, characterization and cDNA cloning of an ML (MD-2-related lipid-recognition) protein from the tobacco hornworm Manduca sexta. The full-length cDNA of this M. sexta ML protein, named MsML-1, is 532bp with an open reading frame of 456bp that encodes a polypeptide of 151 amino acids containing an ML domain. MsML-1 is a secreted glycoprotein and its mRNA is expressed in fat body and hemocytes. The expression level of MsML-1 mRNA in fat body and hemocytes as well as MsML-1 protein in hemolymph are not induced by immune challenge. Recombinant MsML-1 protein specifically binds to LPS from several Gram-negative bacteria and LPS Re mutant, as well as to lipid A, but not to KDO (2-keto-3-deoxyoctonate). Our results suggest that MsML-1 may function as a key accessory protein for LPS signaling in M. sexta against Gram-negative bacterial infection.

A Toll receptor from Manduca sexta is in response to Escherichia coli infection.

Genomic and cDNA sequences of a Toll receptor were cloned from the tobacco hornworm, Manduca sexta. M. sexta Toll (MsToll) gene contains six introns and seven exons. The full-length cDNA of MsToll is 3495 bp with an open reading frame of 2892 bp, which encodes a protein of 963 amino acids. MsToll is a typical single-pass transmembrane protein containing characteristic domain architecture of Toll and Toll-like receptors, including an extracellular domain composing of leucine-rich repeats (LRRs) and a cytoplasmic TIR domain. The deduced amino acid sequence of MsToll is most similar to Apis mellifera Toll (27% identity). Reverse-transcription polymerase chain reaction (RT-PCR) showed that MsToll was expressed in hemocytes, fat body, Malpighian tubule, midgut and epidermis. Real-time PCR analysis showed that MsToll mRNA in hemocytes was significantly induced by Escherichia coli, as well as by yeast (Saccharomyces cerevisiae) and Micrococcus lysodeikticus. However, MsToll transcript in fat body was not induced by these microorganisms. Immunohistochemistry assay showed that MsToll was detected on hemocytes. The TIR domain of MsToll also has high similarity to those of vertebrate TLR4 and zebra fish TLR (35-39% identity). Our results suggest that MsToll may play a role in innate signaling in response to E. coli infections.

Quantitative detection of a marine fish iridovirus isolated from large yellow croaker, Pseudosciaena crocea, using a molecular beacon.

A real-time polymerase chain reaction (PCR) assay utilizing a molecular beacon for the quantitative detection of a marine fish iridovirus isolated from large yellow croaker, Pseudosciaena crocea (LYCIV), was developed, which involved the amplification of a 122bp DNA fragment from a conserved region of LYCIV ATPase gene. The specific probe consisting of two short arm and a central loop sequences complementary to the target amplicon was characterized with respect to its efficiency of quenching (E(ff)), and signal to background ratio by spectrofluorometric analysis of its hybridization with the complementary oligonucleotide target. The positive control plasmid pFHT-ATPase containing the target sequence was quantified to make the standard curve for sample detection after serial 10-fold dilution. Linear coefficient correlations between cycle threshold (C(T)) value and logarithmic positive plasmid concentration were close to one (r(2)=0.998) and the detection limit of the assay was 70 copies of positive plasmid/assay. The specificity of this real-time PCR was also demonstrated by using the genomic DNA templates from the healthy fish, white spot syndrome baculovirus (WSSV), and epizootic heamatopietic necrosis virus (EHNV), respectively. The coefficient of variation (CV) of the assay ranged from 1.16 to 4.42%, depending on the concentration of the positive plasmid. The quantitative detection of different tissues from LYCIV-infected fish showed that the spleen and kidney contained the largest number of viral particles (6.86 x 10(6) and 4.62 x 10(6) viral genome copies/mg tissue, respectively) while no viral DNA was detected in the muscular tissue. These results suggested that the real-time PCR assay reported here could be used for rapid, sensitive, and quantitative detection of LYCIV infection.

Expression of pseudorabies virus gE epitopes in Pichia pastoris and its utilization in an indirect PRV gE-ELISA.

Pseudorabies virus glycoprotein E (PRV gE) has been recognized as a suitable diagnostic antigen for pseudorabies. In order to produce gE antigen in large quantities and at low cost, a gene fragment encoding PRV gE epitopes was expressed in Pichia pastoris expression system. SDS-PAGE and Western blotting revealed that the expression product was two recombinant proteins, approximately 38 and 32 kDa, in the culture supernatant of P. pastoris integrant 72 h after induction. Protein concentration assay showed the expression product amounted to 106.7 mg/l, accounting for 66.67% of total culture supernatant proteins. An indirect PRV gE-ELISA was then established by using the recombinant expression product as a coating antigen. Cross-reactivity assay showed that this antigen was PRV specific. Reproducibility experiment displayed good consistency. Comparison of detection results of 348 field serum samples between PRV gE-ELISA and a commercially available PRV diagnostic kit showed there was no significant difference between these two methods (P > 0.05).