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Concerns regarding food security arise from population growth, global warming, and reduction in arable land. With advances in synthetic biology, food production by microbes is considered to be a promising alternative that would allow rapid food production in an environmentally friendly manner. Moreover, synthetic biology can be adopted to the production of healthier or specifically designed food ingredients (e.g., high-value proteins, lipids, and vitamins) and broaden the utilization of feedstocks (e.g., methanol and CO

Purpose X-ray pulsar navigation (XPNAV) is an autonomous celestial navigation technology for deep space missions. The error in the pulse time of arrival used in pulsar navigation is large for various practical reasons and thus greatly reduces the navigation accuracy of spacecraft near the Earth and in deep space. This paper aims to propose a novel method based on ranging information that improves the performance of XPNAV. Design/methodology/approach This method replaces one pulsar observation with a satellite observation. The ranging information is the difference between the absolute distance of the satellite relative to the spacecraft and the estimated distance of the satellite relative to the spacecraft. The proposed method improves the accuracy of XPNAV by combining the ranging information with the observation data of two pulsars. Findings The simulation results show that the proposed method greatly improves the XPNAV accuracy by 70% compared with the conventional navigation method that combines the observations of three pulsars. This research also shows that a larger angle between the orbital plane of the satellite and that of the spacecraft provides higher navigation accuracy. In addition, a greater orbital altitude difference implies higher navigation accuracy. The position error and ranging error of the satellite have approximately linear relationships with the navigation accuracy. Originality/value The novelty of this study is that the satellite ranging information is integrated into the pulsar navigation by using mathematical geometry.

Pear is one of the main fruits with thousands of years of cultivation history in China. There are more than 2000 varieties of pear cultivars around the world, including more than 1200 varieties or cultivars in China (Legrand et al., 2016). Xinjiang Uygur Autonomous Region is an important pear production region in China with 30 of varieties or cultivars. Pyrus sinkiangensis is the most popular variety, which is mainly distributed in Xinjiang (Zhou et al., 2018). Chlorogenic acid (CGA), p-coumaric acid, and arbutin are the main polyphenols in pear fruit, and their levels show great differences among different varieties (Li et al., 2014). CGA is a potential chemo-preventive agent, which possesses many important bioactivities including antioxidant, diabetes attenuating, and anti-obesity (Wang et al., 2021). Therefore, the specific CGA content of a variety is considered the embodiment of the functional nutritional value of pears.

Gastric cancer is one of the most common cancers and the leading causes of cancer mortality. However, the molecular mechanisms of gastric cancer malignancy remain unclear. Long noncoding RNAs (lncRNAs) have been well documented in controlling cancer progression. Identification of critical lncRNAs in gastric cancer will provide new sights into the regulation mechanism of gastric cancer. Here, we screened differentially expressed lncRNAs in gastric cancer tissues and matched adjacent tissues and found that lncRNA LIT3527, a 486-nucleotide (nt) sense transcript, was frequently upregulated in gastric cancer tissues. Knockdown of LIT3527 dramatically suppressed proliferation and migration of gastric cancer cells through inducing severe cell death but not affecting cell cycle. Mechanistically, we uncovered that depletion of LIT35227 induced significant cell apoptosis and autophagy through inhibiting AKT/ERK/mTOR signaling pathway. Targeting LIT3527 showed a robust inhibition of lung metastasis of gastric cancer cells. Taken together, these results suggest that LIT3527 is essential for gastric cancer cell survival through maintaining mTOR activity, suggesting that it may be clinically valuable as a therapeutic target for gastric cancer.

Geomagnetic field has important applications in Earth Science, earthquake prediction, aerospace, national defense construction and other areas. Therefore, accurate modeling of regional geomagnetic field is very important. Geomagnetic assimilation method can effectively improve the accuracy of regional vector geomagnetic data, and then promote the establishment of high-precision geomagnetic regional model. The geomagnetic stations at different latitudes and longitudes have different influences on the geomagnetic assimilation of vector geomagnetic data. However, traditional geomagnetic assimilation methods do not take into account the differences in latitude and longitude, which result in low accuracy of the geomagnetic assimilation of vector geomagnetic data. To solve the problem, this paper proposes a new geomagnetic assimilation method based on the three weighting factors of direction, distance and a parameter k. In this method, the longitude differences and latitude differences of different stations are taken as the weight elements to participate in the weight determination, and parameter k is set to further modify the weight, so as to achieve the high precision geomagnetic assimilation to regional vector geomagnetic data. Based on the real observation data of five stations in the European region of station network in the world data center (WDC), this paper conducted geomagnetic assimilation of the vector geomagnetic data of different stations. The experimental results show that at five stations which include some central stations and some marginal stations, for the F, H, D and I geomagnetic elements, the geomagnetic assimilation accuracy of the proposed method is better than that of the method based on the distance weighting method both on magnetically quiet day and on magnetically disturbed day. In addition, the results also show that the geomagnetic assimilation accuracy of FUR station, which is a marginal station, is significantly improved by the proposed method. On magnetically disturbed day, the error of F component is reduced by 0.6 nT, and the error of H component is reduced by 1 nT. On magnetically quiet day, the error of F component is reduced by 0.4 nT, and the error of H component is reduced by 0.1 nT. The above results prove the effectiveness and feasibility of the proposed method in the geomagnetic assimilation of vector geomagnetic data, especially for the vector geomagnetic data of marginal area.

Cronobacter sakazakii (Cs) is a typical foodborne bacterium that infect powdered infant formula (PIF) worldwide. In this study, a recombinant antimicrobial peptide, branded as Funme peptide (FP)was applied to protect PIF from Cs contamination. The result from the antimicrobial activity assay showed that the minimum inhibitory concentration (MIC) of BMAP-27 peptide, FP and Ampicillin against Cs were 250.0, 125.0 and 15.6 μg/mL, respectively, indicating FP possessed higher MIC than that of Ampicillin, and lower MIC than that of BMAP-27. The minimum biofilm eradication concentration (MBEC) assay showed that FP at 2 × MIC (250.0 μg/mL) could completely eradicated Cs biofilms. The antibacterial activity of FP might be due to the increasing permeability and the release of cytoplasmic β-galactosidase of Cs. The results acquired from transmission electron microscopy and scanning electron microscopy indicated that FP induced the disruption and dysfunction of cell walls and membranes. Moreover, safety assay showed that FP had low cytotoxicity to human erythrocytes. The present study investigated the antibacterial effects and mechanisms of FP against Cs, providing promising evidence to apply this novel antimicrobial agent against Cs contamination in foods and food processing facilities.

OBJECTIVES: Estrogen plays an important role in for growth and development of reproductive system in female. The major royal jelly (RJ) has a significant estrogenic-like effect for many female animals. The major RJ proteins (MRJPs) are the central constituents responsible for the physiological activities of RJ. In recent years, we have found that MRJPs possesses functions to increase fecundity associated with estrogenic effect in Drosophila. However, if MRJPs are the specific active ingredient mediating estrogenic effect of RJ and related action mechanism in mammalians remains unclear. METHODS: Neonatal immature female mice (FC) were divided into four groups fed MRJPs with doses of 0, 125, 250 and 500 mg/kg/body weight (M125, M250 and M500), respectively. The freeze-dried MRJPs powder was administrated daily for 45 consecutive days. The effects of MRJPs on the puberty onset, ovarian follicular development and serum estradiol levels in FC were evaluated. RESULTS: The times of estrus in M125, M250 and M500 were accelerated by 10.7%, 15.5% and 10.7%, the ovarian index of M125 and M250 and M500 were increased by 26.8% and 32.1% and 1.7%. The number of secondary follicles in M125 and M250 and M500 were increased by 50.7%,78.8% and 38.6%, the Graafian follicles in M125 and M250 and M500 were increased by 600.0% and 774.0% and 150.0%. M500 induced multi-oocyte follicles. The serum estradiol levels of M125, M250 and M500 were increased by 47.1%, 64.9% and 31.1%, the action of MRJPs raising hormone secretion level is mainly via upregulating expression of ERβ gene. Antioxidant parameters of ovarian tissue showed that the malondialdehyde levels in M125 and M250 were decreased, the superoxide dismutase activities and glutathione peroxidase activities in M125 and M250 were increased, respectively. CONCLUSIONS: Oral administration of MRJPs may accelerate onset of puberty and promote follicular development in immature FM. The reproductive performance promotion of MRJPs was associated with raising estrogenic activity and antioxidant potential to reproductive system, upregulating expression of ERβ gene to raise hormone secretion and promote ovary development in FM. FUNDING SOURCES: The National Natural Science Foundation of China and US Department of Agriculture, Agriculture Research Service.

In this study, a rapid and reliable gold nanoparticles immunochromatographic strip (GNPs-ICS) assay based on a full-length recombinant antibody (rAb) was established for pyraclostrobin detection in food samples. First, a hybridoma PY-C7 secreting pyraclostrobin-specific monoclonal antibody (mAb) was produced. The variable region sequences of PY-C7-mAb were obtained by PCR and Sanger sequencing and used for the rAb expression in HEK293(F) cells. By GNPs-ICS assay, the visual LOD of pyraclostrobin standards was 0.1 mg L−1 (rAb) and 0.2 mg L−1 (mAb). Validated by recovery test, the visual LOQ of pyraclostrobin could meet the MRLs of Chinese food safety standard in strawberry, banana and Chinese cabbage samples by GNPs-mAb/rAb-ICS, in which the rAb showed better sensitivity and stability. Moreover, the GNPs-rAb-ICS showed comparable reliability with LC-MS/MS for actual sample detection. Above all, GNPs-ICS assay based on the full-length rAb was qualified for rapid detection of pyraclostrobin in food samples.

In this study, a rapid and reliable gold nanoparticles immunochromatographic strip (GNPs-ICS) assay based on a full-length recombinant antibody (rAb) was established for pyraclostrobin detection in food samples. First, a hybridoma PY-C7 secreting pyraclostrobin-specific monoclonal antibody (mAb) was produced. The variable region sequences of PY-C7-mAb were obtained by PCR and Sanger sequencing and used for the rAb expression in HEK293(F) cells. By GNPs-ICS assay, the visual LOD of pyraclostrobin standards was 0.1 mg L−1 (rAb) and 0.2 mg L−1 (mAb). Validated by recovery test, the visual LOQ of pyraclostrobin could meet the MRLs of Chinese food safety standard in strawberry, banana and Chinese cabbage samples by GNPs-mAb/rAb-ICS, in which the rAb showed better sensitivity and stability. Moreover, the GNPs-rAb-ICS showed comparable reliability with LC-MS/MS for actual sample detection. Above all, GNPs-ICS assay based on the full-length rAb was qualified for rapid detection of pyraclostrobin in food samples.

At present, China’s BDS-3 basic system has been completed and started to provide global services. However, the accuracy of satellite clock difference seriously restricts the service performance of BDS, and the performance of satellite atomic clock directly determines the accuracy of satellite clock difference. To solve this problem, this paper studies and evaluates the performance of BDS-3 spaceborne atomic clock in detail. Based on the precision satellite clock data of BDS from August to October 2019, using the median method, this paper pre-processed the BDS-2 and BDS-3 data, and obtained the fitting residuals of the spaceborne atomic clock by using the polynomial fitting method. In addition, in the frequency domain, this paper studied and compared the periodic characteristics of spaceborne atomic clock of BDS-3 and BDS-2. The experimental results show that all the clock difference of BDS show significant periodic characteristics, and the main period of BDS satellite clock difference is 12 h and 24 h respectively, corresponding to 0.5 times, 1 times and 2 times of each satellite orbit period. Compared with BDS-2, the main period term of BDS-3 is clearer, more accurate and more stable. In addition, the experiment also shows that the period of satellite clock difference is different in different orbits and in the same orbit the periodic term of satellite clock difference is also different. The period term of BDS-3 is consistent with that of other MEO satellites. Finally, the performance analysis of BDS atomic clock shows that the performance of BDS-3 hydrogen atomic clock is better than that of BDS-2 atomic clock.

Spermatogenesis and hormones secretions are crucial endocrine and physiological process for maintaining the life. Royal Jelly (RJ) bioactive components are Major Royal Jelly Proteins (MRJPs), owing exceptional biological properties. However, the effects of RJ on pup&rsquo, s testicular development during neonatal and pubertal period exposure hasn&rsquo, t been adequately studied. The aim of the study was to detect neonatal sexual hormones concentration and histopathological changes on testicular development of the male progeny after oral exposure to freeze-dried RJ for 35 consecutive days. After mice give birth, male pups were collected together, separated by sex, and randomly standardized to seven (7) male pups per dam. Male pups were assigned to control diet (CON group), low dose RJ (L-RJ group) diet (control diet + 125 mg/kg/day RJ), moderate dose RJ (M-RJ group) diet (control diet + 250 mg/kg/day RJ) and high dose of RJ (H-RJ group) diet (control diet + 500 mg/kg/day RJ). After weaning, male pups were continuously fed with freeze-dried RJ until the age of PNDs 35. The results revealed that, oral M-RJ (250 mg/kg/day) administration significantly (p &lt, 0.05) increased the testis weight, the diameter of seminiferous tubule and the height of seminiferous epithelium of offspring mice at PNDs 14. However, high-dose RJ (500 mg/kg/day) decreased the diameter of seminiferous tubule but increased the height of seminiferous epithelium of male offspring (p &lt, 0.05) at the same time point. Furthermore, oral M-RJ treatment significantly (p &lt, 0.05) increased the testis weight and spermatogenesis at PNDs 21. Whereas, oral H-RJ treatment significantly (p &lt, 0.05) reduced the diameter of seminiferous tubule and the height of seminiferous epithelium at PNDs 21. At PNDs 35, oral M-RJ treatment increased the testis weight, the diameter of seminiferous tubule and the level of FSH. While, high-dose of RJ reduced testis weight and size (diameter of seminiferous tubule and height of seminiferous epithelium), ratio of apoptotic germ cells and incomplete spermatogenesis collectively. In addition, sexual hormone secretions (FSH, LH, E2) were decreased after RJs treatment (L-RJ, M-RJ, H-RJ) at PNDs 21 respectively. In conclusion, the results concluded that oral administration of low and moderate doses of RJ could enhance the development of testis at neonate period until pubescent, whereas unfavorable adverse effects induced by high dose of RJ might remain.

Major royal jelly proteins (MRJPs) have been used as endogenous biomarkers for honey authentication. However, no study on quantification of MRJPs in honey authentication was reported. In order to develop a new honey authenticity method based on quantitative analysis of MRJPs in honey, trypsin-digested peptides from MRJPs were examined by mass spectrometry (MS). Three peptides, YNGVPSSLNVISK, TLQMIAGMK, and LTVAGESFTVK were selected as specific markers for MRJP1, MRJP 2 and MRJP 3(MRJP1∼3), respectively. An ultra performance liquid chromatography-triple quadrupole MS (UPLC-TQMS) method used for quantification of MRJPs in honey was developed and validated. A database on the MRJP1∼3 contents of honey established by quantification of 70 authentic samples showed a potential application in honey authenticity identification. The analysis results of 10 commercial honey samples by UPLC-TQMS with reference to the MRJP1∼3 database of authentic honey were compared and confirmed by widely used isotope ratio mass spectrometry, a AOAC Official Method. In conclusion, the results showed our method, a proteomic-based UPLC-TQMS method, has a high accuracy, sensitivity and specificity for honey authenticity.

Major royal jelly protein-1 (MRJP1) is the most abundant glycoprotein of royal jelly (RJ) and is considered a potential component of functional foods. In this study, we used silkworm transgenic technology to obtain five transgenic silkworm lineages expressing the exogenous recombinant Chinese honeybee, Apis cerana cerana, protein-1 (rAccMRJP1) under the control of a fibroin light chain (Fib-L) promoter in the posterior silk glands. The protein was successfully secreted into cocoons; specifically, the highest rAccMRJP1 protein content was 0.78% of the dried cocoons. Our results confirmed that the protein band of the exogenous rAccMRJP1 protein expressed in the transgenic silkworm lineages was a glycosylated protein. Therefore, this rAccMRJP1 protein could be used as an alternative standard protein sample to measure the freshness of RJ. Moreover, we also found that the overall trend between the expression of the endogenous and exogenous genes was that the expression level of the endogenous Fib-L gene declined as the expression of the exogenous rAccMRJP1 gene increased in the transgenic silkworm lineages. Thus, by employing genome editing technology to reduce silk protein expression levels, a silkworm bioreactor expression system could be developed as a highly successful system for producing various valuable heterologous proteins, potentially broadening the applications of the silkworm.

In this study, a rapid and sensitive immunochromatographic strip (ICS) assay, based on quantum dots (QDs), was developed for the qualitative and quantitative detection of acetamiprid in agricultural samples. Acetamiprid-ovalbumin conjugates (ACE-OVA) and goat anti-mouse IgG were sprayed onto a nitrocellulose membrane as a test and control line. Two kinds of anti-acetamiprid monoclonal antibodies (mAb) obtained in our lab were characterized by the ELISA and surface plasmon resonance assay. The competitive immunoassay was established using a QDs-mAb conjugate probe. The visual detection limit of acetamiprid for a qualitative threshold was set as 1 ng/mL to the naked eye. In the quantitative test, the fluorescence intensity was measured by a portable strip reader and a standard curve was obtained with a linear range from 0.098 to 25 ng/mL, and the half maximal inhibitory concentration of 1.12 ng/mL. The developed method showed no evident cross-reactivities with other neonicotinoid insecticides except for thiacloprid (36.68%). The accuracy and precision of the developed QDs-ICS were further evaluated. Results showed that the average recoveries ranged from 78.38 to 126.97% in agricultural samples. Moreover, to test blind tea samples, the QDs-ICS showed comparable reliability and a high correlation with ultra-performance liquid chromatography-tandem mass spectrometry. The whole sample detection could be accomplished within 1 h. In brief, our data clearly manifested that QDs-ICS was quite qualified for the rapid and sensitive screening of acetamiprid residues in an agricultural product analysis and paves the way to point-of-care testing for other analytes.

The major royal-jelly proteins (MRJPs) are the main constituents responsible for the specific physiological role of royal jelly (RJ) in honeybees. Male and female Drosophila flies were fed diets containing either no MRJPs (A) or casein (B) at 1.25% (w/w) of diet or MRJPs at 1.25% (C), 2.50% (D), or 5.00% (E). Diets B, C, D, and E increased mean lifespan by 4.3%, 9.0%, 12.4%, and 13.9% in males and by 5.8%, 9.7%, 20.0%, and 11.8% in females in comparison to results from diet A, respectively. The diet supplemented with 2.50% MRJPs seems to have the optimal dose to improve both physiological and biochemical measures related to aging in both sexes. Interestingly, lifespan extension by MRJPs in Drosophila was positively associated with feeding and fecundity and up-regulation of copper and zinc-superoxide dismutase (CuZn-SOD) and the Egfr-mediated signaling pathway. This study provides strong evidence that MRJPs are important components of RJ for prolonging lifespan in Drosophila.

Heat stress (HS) causes serious physiological dysfunction associated with cardiovascular diseases. Curcumin (CUR) may increase animal survival and lifespan under HS. However, its effects and mechanism on mammal are underexplored. The goal of this study was to examine the protective effect of CUR on the cardiac health of mice exposed to HS. Mice were divided into six groups (n=8 per group): no-heat treatment (NHT), heat treatment (HT), aspirin, CUR 50 mg/kg/day, CUR 100 mg/kg/day and CUR 200 mg/kg/day. After administration for 4 weeks, except for NHT, other groups were exposed once to HS at 41°C for 20 min. After HS treatment, the physiological-related indexes of blood pressure, rectal temperature and heart rate were measured. Serum biochemical indexes and the levels of cardiac troponin I (cTn-I) in serum and angiotensin II (Ang II) in cardiomyocytes were analyzed. Furthermore, the mRNA and proteins levels of angiotensin receptor 1 (AT1), 78-kDa glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP) and B-cell lymphoma 2 (Bcl-2) were measured. Our results indicated that CUR supplementation could alleviate HS-induced physiological disorders and the increasing of cTn-I and Ang II. The expression of AT1 gene in HT group was significantly higher than that of CUR groups, indicating the cardioprotective effects of CUR. Moreover, the levels of GRP78 and CHOP proteins in the HT group were significantly higher than those of CUR groups, indicating that CUR supplementation reversed the endoplasmic reticulum HS-mediated apoptosis. In summary, CUR supplementation alleviates physiological stress and cardiac damage caused by HS.

Turmeric residue (TR), containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles (SSTs), Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets: basal diet (the control group, n=160) and an interventional diet supplemented with 10% TR (the TR group, n=160). Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase (SOD) activity of SST liver by 112.8%, and decreased the malondialdehyde (MDA) content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography (HPLC) analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were (1.69±0.30) and (0.14±0.03) μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.

This paper proposes a novel four-switch three-phase brushless dc motor control scheme based on quasi Z-source network (QZFSTP), which improves the utility ratio of DC voltage, extends the range of speed and increases the output torque. The additionally partial circuits of quasi Z-source network and the bridge arm of four-switch inverter constitute the quasi Z-source converter. During the operation of motor, shoot-through states are inserted. Then the input voltage of inverter increases and the performance of motor can be markedly improved. The operating principle of four-switch three-phase (FSTP) brushless dc motor are analyzed, and the new topology and its controlling method are illustrated in detail. The experimental result indicated that the novel circuit structure could solve above problems effectively.

Curcumin is a polyphenolic bioactive compound in turmeric. We examined if antioxidant effects of curcumin are associated with lifespan extension in Drosophila. In this experiment, females and males of Drosophila were fed diets either containing no curcumin (C0) or supplemented with curcumin at 0.5 (C1) and 1.0 (C2) mg/g of diet. The levels of malondialdehyde (MDA), enzyme activity of superoxide dismutase (SOD), and expression of seven age-related genes in females and males were analyzed. We found that C1 and C2 increased mean lifespan by 6.2 % and 25.8 % in females, and by 15.5 % and 12.6 % in males, respectively. Meanwhile, C1 and C2 significantly decreased MDA levels and increased SOD activity in both genders. Diets C1 in females and C2 in males are effective in extending mean lifespan and improving levels of two physiological and biochemical measures related to aging in Drosophila. Lifespan extension of curcumin in Drosophila was associated with the up-regulation of Mn-SOD and CuZn-SOD genes, and the down-regulation of dInR, ATTD, Def, CecB, and DptB genes. The present results suggest that curcumin increases mean lifespan of Drosophila via regulating gene expression of the key enzyme SOD and reducing accumulation of MDA and lipid peroxidation. This study provided new insights for understanding the anti-aging mechanism of curcumin in Drosophila.

The dynamic performance of current is influenced and the speed is limited, for the irregular dc-link voltage utilization in the control of four-switch three-phase (FSTP) BLDC motor. This paper presents a novel topology, which combines quasi Z-source converter and FSTP drive circuit. The drawbacks of FSTP BLDC motor are analyzed, the control methods of each mode in quasi Z-source four-switch three-phase (QZFSTP) topology are illustrated. Simulations for QZFSTP BLDC motor were constructed in MATLAB/Simulink circumstance. The simulation experiments showed that dc-link voltage of inverter could reach the rating value quickly, the speed and load range were widened with low dc-link voltage.

Shiitake ( Lentinula edodes ) mushrooms were packed in biorientated polypropylene (BOPP) bags and exposed to different doses of gamma irradiation (1.0, 1.5, and 2.0 kGy) within the packaging, heat sealed and stored at 4 °C for 20 d. Of the three doses, 1.0 kGy was most effective in maintaining a high level of firmness. Samples treated with 1.0 kGy also exhibited smaller initial declines in soluble protein, higher increases in total sugar content and lower levels of malondialdehyde accumulation. Furthermore, 1.0 kGy promoted the accumulation of phenolics compound and showed higher antioxidant ability during storage. At higher doses, 2.0 kGy resulted in a higher microbial reduction, but showed negative effects on texture, chemical properties and functional components. All the gamma irradiation were effective in retarding mushroom sensory deterioration. Thus, application of gamma irradiation in combination with MAP can extend the storage life of shiitake mushroom up to 20 d.

Major royal jelly protein 1 (MRJP1) is the most abundant member of the major royal jelly protein (MRJP) family of honeybee. Mature MRJP1 cDNA of the Chinese honeybee (Apis cerana cerana MRJP1, or AccMRJP1) was expressed in Pichia pastoris. SDS-PAGE showed that recombinant AccMRJP1 was identical in molecular weight to the glycosylated AmMRJP1 from the Western honeybee (Apis mellifera). Western blots probed with anti-AccMRJP1 antibody demonstrated that recombinant AccMRJP1 and soluble protein of the Western honeybee RJ (AmSPRJ) contained immunoreactive MRJP1. The 57 kDa protein in AmSPRJ contained an N-terminal amino sequence of N-I-L-R-G-E, which is identical to that previously characterized in AmMRJP1. The molecular weight of recombinant AccMRJP1 was decreased from 57 to 48 kDa after deglycosylation, indicating that AccMRJP1 was glycosylated. The recombinant AccMRJP1 significantly stimulated Tn-5B-4 cell growth, similar to AmSPRJ and fetal bovine serum, and affected cell shape and adhesion to the substrate.

Royalisin is an antibacterial peptide found in Royal Jelly. Two gene fragments of Chinese honeybee (Apis cerana cerana) head, 280 bp cDNA encoding pre-pro-Acc-royalisin (PPAR) of 95 amino acid residues, and 165 bp cDNA encoding mature Acc-royalisin (MAR) of 51 amino acid residues were cloned into the pGEX-4T-2 vector. They were then transformed individually into Escherichia coli for expression. Two expressed fusion proteins, glutathione S-transferase (GST)-PPAR of 36 kDa and GST-MAR of 32 kDa were obtained, which were cross reacted with GST antibody accounting for up to 16.3% and 15.4% of bacterial protein, respectively. In addition, 41% of GST-PPAR and nearly 100% of GST-MAR were soluble proteins. Both lysates of the two purified fusion proteins displayed antibacterial activities, similar to that of nisin against Gram-positive bacteria strains, Staphylococcus aureus, Bacillus subtilis and Micrococcus luteus. MAR peptide released from the thrombin-cleaved GST-MAR fusion protein has a stronger antibacterial activity than that of GST-MAR fusion protein.

The comparative effect of tuna oil (TO) and salmon oil (SO) on the plasma and liver lipid and fatty acid compositions in Sprague Dawley rats was investigated. The total triacylglycerol (TG) and total cholesterol (TC) concentrations in liver was significantly decreased in the TO group; TG level in liver was also significantly decreased in the SO group. The mRNA expression of HMG-CoA reductase in liver was significantly down-regulated in the TO and SO groups relative to the control group. The plasma TG and TC were decreased in TO, but not in SO; plasma low-density lipoprotein and very low-density lipoprotein levels in TO and SO were decreased compared with the control group. The total n-3 polyunsaturated fatty acid (PUFA) in plasma and liver phospholipids was significantly elevated in the TO and SO. Docosahexaenoic acid (22:6n-3) and eicosapentaenoic acid (20:5n-3) in tissues were significantly increased in the TO and SO, respectively. In this study, TO had a more beneficial effect on liver TC and plasma TG, TC, high-density lipoprotein in rats than SO. The likely mechanism for lowering liver and plasma cholesterol by n-3 PUFA is to suppress the mRNA expression of gene encoding HMG-CoA reductase responsible for cholesterol biosynthesis. PRACTICAL APPLICATIONS The beneficial effects of n-3 polyunsaturated fatty acids (PUFAs) from fish and fish oil on human health is derived from their role in modulating membrane lipid composition and affecting metabolic and signal-transduction pathways. In the present study, we demonstrated that n-3 PUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from tuna and salmon oils can be effectively incorporated into tissue membranes. Tuna oil rich in DHA has more beneficial effect on liver total cholesterol (TC) and plasma triglyceride, TC and HDL in rats than salmon oil, which is rich in EPA. The present data could provide information for the potential application of fish oils as components of functional food, and selected for fortification with different fish oils.

Drosophila melanogaster has been a widely used as a model system for its powerful genetic tools. However, it remains to be illustrated if Drosophila can be used to examine the biochemical and physiological metabolism of eicosanoids. Thus, the analysis on the metabolism of C20 polyunsaturated fatty acids (PUFA) in Drosophila was implemented with high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Fatty acid (FA) analysis of the whole body, head, and thorax-abdomen in Drosophila showed C20 PUFA could only be found in Drosophila fed diets supplemented with eicosapentaenoic acid (EPA) and arachidonic acid (ARA), but not in Drosophila fed base diets. The C20 PUFA were found in abundance in the head. Drosophila fed ARA- and EPA-supplemented diets yielded 15S-hydroxy-5Z,8Z,11Z,13E-eicosatetraenoic acid [15(S)-HETE] and 15S-hydroxy-5Z,8Z,11Z,13E,17Z-eicosapentaenoic acid [15(S)-HEPE], respectively, while other sampled eicosanoids could not be detected. Similar results were obtained by incubating fly tissue supplemented with ARA or EPA. Furthermore, a genome sequence scan indicated that no gene encoding the key enzymes synthesizing eicosanoids were found in Drosophila. These findings demonstrate that Drosophila may possess a special lipid metabolic system, which is different from mammals.

Major royal jelly protein 1 (MRJP1), designated apalbumin 1, has been regarded as a freshness marker of royal jelly (RJ). A MRJP1-specific peptide (IKEALPHVPIFD) identified by bioinformatics analysis of homologous members of the major royal protein family was synthesized and used to raise polyclonal anti-MRJP1 antibody (anti-SP-MRJP1 antibody). Western blot analysis showed that anti-SP-MRJP1 antibody only reacted with MRJP1 in RJ. In contrast, the previously reported antibody against recombinant MRJP1 (anti-R-MRJP1 antibody) reacted with other members of MRJP family in RJ. Enzyme-linked immunosorbent assay (ELISA) using anti-SP-MRJP1 antibody demonstrated that MRJP1 content in RJ stored at 40 °C significantly degraded by 37.3%, 55.9%, 58.0%, 60.6%, 65.7%, 72.7%, and 73.1% at 7, 14, 21, 28, 35, 42, and 49 d, respectively, when compared with MRJP1 content in fresh RJ (0 d). Optical density analysis of MRJP bands from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profiles demonstrated that the degradation of MRJP1, MRJP2, MRJP3, and MRJP5 in RJ was strongly and positively correlated with the period of storage (P

With the improvement and updating of GPS, GLONASS navigation system, and the gradual establishment of GALILEO and China’s BeiDou system (BDS) navigation system, Multi-system GNSS navigation systems have become the main research directions. In order to achieve the compatibility and interoperability among the GNSS systems, accurately determine the time difference between different systems is the key. Based on this, this paper adopted the GNSS observation data, which is the output of the multi-mode dual-band receiver, and the GNSS system’ navigation message to monitor the time difference between different GNSS navigation systems. Because the BIPM T bulletin has no BDS data, so the measured time difference data of GLONASS and GPS and the corresponding time difference data of BIPM T bulletin were used to be evaluated. In this paper, the maximum, minimum, mean, mean square error and the RMSE of BDS, GPS and GLONASS time difference data were accumulated. 310 days’ time difference data were used to evaluation the difference. The results show that the residual’ standard deviation between GLONASS, GPS time difference and the results of T bulletin is 4.28 ns, and the residual’ standard deviation between BDS and GPS, GLONASS system can reach 5 and 10 ns in optimal conditions.

Royalisin from royal jelly (RJ) is a valuable peptide both for the prevention of honeybee diseases and for RJ preservation. ELISA for fast determination of royalisin content in hemolymphe (RCH) of honeybees with polyclonal antibody against recombinant royalisin from Asian honeybee was established. Assay on RCHs of health samples from Asian honeybee and Western honeybee showed the former (7.06 μg/mL) was significantly higher than that of the latter (5.64 μg/mL, p < 0.01). Moreover, relative to the non infection, the RCHs of Asian honeybees at 24 and 48 h post infection of Eschericha coli were higher than those of Western honeybees by 32.90% and 29.66%, respectively. Evidence revealed that Asian honeybee possesses higher innate immunity and immune response against bacteria in relation to the Western honeybee. The method will be a potential tool for detection of resistant levels to pathogens in honeybees and for quantification of royalisin in RJ products.