Effects of different drying methods on phenolic components and in vitro hypoglycemic activities of pulp extracts from two Chinese bayberry(Myrica rubra Sieb.et Zucc.)cultivars

The effects of two different drying methods,namely hot-air drying and freeze drying,on the phenolic profiles,antioxidant and hypoglycemic activities of pulp extracts from two main Chinese bayberry cultivars(’Biqi’or’BQ’and’Dongkui’or’DK’)were evaluated.The results showed that’BQ’bayberry provided higher total phenolic(TPC),total flavonoid(TFC)and total anthocyanin(TAC)contents than’DK’bayberry after the same drying method,while its antioxidant and hypoglycemic activities were highly affected by drying method.Freeze-dried samples possessed significantly higher TPC,TFC and TAC,and exhibited more potent antioxidant and hypoglycemic activities than hot-air dried ones(P<0.05).Freeze-dried’DK’bayberry exhibited similar antioxidant activities and a-amylase inhibitory activity,but higher a-glucosidase inhibition than freeze-dried’BQ’bayberry(P<0.05).Compared with hot-air dried samples,freeze-dried samples had significantly higher contents of cyanidin-3-O-glucoside,myricitin-3-O-rhamnoside,quercetin-3-O-galactoside,quercetin-3-O-glucoside and quercetin-3-O-rhamnoside,which had been proved to be the main contributors to the in vitro hypoglycemic activities of bayberry pulp extract.All these results demonstrate that freeze drying is more suitable for the preservation of phenolic components in the pulp extract of Chinese bayberry,and the pulp extract of freeze-dried’DK’could be applied as a potential hypoglycemic food additive.

Pesticide residues in bayberry(Myrica rubra)and probabilistic risk assessment for consumers in Zhejiang,China

As pesticide residues in bayberry has raised serious concern from the public in China, a monitoring survey was carried out during 2013–2014 and 157 samples were analyzed in total. Twenty-three pesticides were detected among the 44 pesticides analyzed and at least one pesticide was detected in 63% of 99 samples. Whereas 45.6% of samples were found with two or more pesticide residues, and 23.6% of samples with four or more pesticide residues. Probabilistic risk assessments indicated that estimated daily intake（EDI） of cyhalothrin at the P97.5th percentile level is 1.11 times larger than the acceptable daily intake（ADI） for children, the estimated short-term intake（ESTI） at the P97.5th percentile level is 1.9 and 1.78 times larger than the acute reference dose（ARf D） for adult and children, respectively, indicating the potential risk concern from pyrethroids. EDI of the pesticides with anti-androgenic effects ranged from 0.15–2.46 of ADI, the probability of exposure exceeding the ADI was 7.1 and 31.1% for adults and children, respectively, the probability of exposure of pyrethroids exceeding the ADI was 3.8% for children. Exposures for other pesticides and groups were below 1.0. Because the co-occurrence of frequency of cyhalothrin and cypermethrin was 9.55%, the combinations of pesticides detected with anti-androgenic effects has not been found in the present monitoring, the results indicate that the pesticide residues in bayberry will not constitute serious public health risk, however, they are significant for the management of pesticide use on bayberry and dietary health risk in China.

Development of Antioxidant Packaging Film Based on Chinese Bayberry Tannin Extract and Polyvinyl Alcohol

The current work explores the potential use of commercial Chinese bayberry tannin(BT)to develop antioxidant PVA-based films using solvent casting process for packaging applications.The effect of BT concentration on opa-city,water resistance and antioxidant capacity of resulting films was investigated.Properties like tensile strength,thermal behavior,and morphological aspects were also characterized.The experimental results showed that PVA/BT films formed with uniformly brown color and generally good transparency,offering good antioxidant ability.The PVA film containing BT presented slightly higher water resistance according to the results of moisture content and water vapor permeability,especially at low BT content(<10 wt%).The PVA can be compounded with up to 10 wt%BT without any obvious deterioration in the tensile strength.The PVA/BT films exhibited better thermal degradation behavior compared with PVA alone because of the chemical bonds of PVA-BT and the for-mation of char at high temperature.Based on the results,PVA incorporated with Chinese bayberry tannin may provide broader formulation options for packaging materials with antioxidant action.

Assisted Compatibility, and Balanced Regulation of the Mechanical, Thermal, and Antioxidant Activity of Polyvinyl Alcohol-Chinese Bayberry Tannin Extract Films Using Different Di-Aldehydes as Cross-Linkers

Polyvinyl alcohol(PVA)-based films containing Chinese bayberry tannin(BT)were prepared by cross-linking using glyoxal,glutaraldehyde and dialdehyde starch,individually.The presence of cross-linkers was evident to promote the transparency and decrease the moisture content of PVA/BT films,while the water solubility stayed almost unchanged in the cross-linked PVA/BTfilms.All cross-linkers provided promotion of the water vapor per-meability,mechanical property and thermal stability of PVA/BT films.The best water vapor barrier capacity was found in case of glutaraldehyde cross-linked PVA/BT film,while the highest tensile strength was encountered in case of glyoxal cross-linked PVA/BT films,compared with the uncross-linked films.The scavenging action of the films towards DPPH radical activity was influenced by the nature of each cross-linker.Namely,the PVA/AT film cross-linked by glutaraldehyde acquired the lowest radical scavenging activity in a certain time,suggesting that glutaraldehyde decreased the release rate of BT from PVA.Based on the experimental data,glutaraldehyde and dialdehyde starch could be more suitable for PVA/BT film preparation since they can promote the intermo-lecular interaction of PVA and BT to a reasonable extent.

Risk Assessment of Quality Safety of Nonlocal Red Bayberry in Cixi City

The nonlocal red bayberry sold in Cixi City were quantitatively analyzed for consecutive four years from 2010 to 2013, in order to understand their pesti- cide pollution. The results showed that the detectable rate of pesticide was 55.56%, and the pesticide detectable rate of samples was 59.09% in red bayberry. The exceeding standard rate of pesticides was 15.87%. In terms of safety index, the risk and safety state of all pesticides were within an acceptable range except cyhalothrin. In terms of risk coefficient, omethoate, triazophos and isocarbophes were at high-risk state, and the remaining 19 kinds of pesticides were at low-risk state.

SSR Marker Technique and Its Application on Chinese Bayberry( Myrica rubra,Myricaceae)

SSR marker technique was summarized from the aspects of types and genetic characteristics of SSR loci, principles and characteristics of SSR technique, and development of SSR markers. The literatures about the applications of SSR markers on germplasm studies of Chinese bayberry were reviewed to provide a refer- ence for related studies.

An object detection method for bayberry trees based on an improved YOLO algorithm

To quickly detect and count the number of bayberry trees,this paper improves the YOLO-v4 model and proposes an optimal YOLO-v4 method for detecting bayberry trees based on UAV images.We used the Leaky_ReLU activation function to accelerate the model extraction speed and used the DIoU NMS to retain the most accurate prediction boxes.In order to increase the recall rate of the object detection and construct the optimal YOLO-v4 model,the K-Means clustering method was embedded into DIoU NMS.We trained the model using UAV images of bayberry trees,it was determined that the optimal YOLO-v4 model threshold was 0.25,which had the best extraction effect.The optimal YOLO-v4 model had a detection accuracy of up to 97.78%and a recall rate of up to 98.16%on the dataset.The optimal YOLO-v4 model was compared with YOLO-v4,YOLO-v4 tiny,the YOLO-v3 model,and the Faster R-CNN model.With guaranteed accuracy,the recall rate was higher,up to 97.45%,and the detection of bayberry trees was better in different contexts.The result shows that the optimal YOLO-v4 model can accurately achieve the rapid detection and statistics of the number of bayberry trees in large-area orchards.

Accurate and rapid image segmentation method for bayberry automatic picking via machine learning

Due to the short ripening period and complex picking environment,bayberry generally relies on mechanical equipment for picking,especially the automatic picking system guided by vision.Thus,it is crucial to locate the bayberry in the view accurately and rapidly.Although efforts have been made,the existing methods are difficult to implement due to the limited amount of data and the processing speed.In this study,an accurate and rapid segmentation method based on machine learning was proposed to address this problem.First,the images collected by the visual guidance system were pre-processed by contrast-limited adaptive histogram equalization(CLAHE)based on the Y component of the YUV color space.Taking advantage of the color difference map of RB and RG for the segmentation of different colors,an adaptive color difference map foreground segmentation method was then adopted for bayberry region foreground segmentation.Finally,distance transforms and marking control watershed methods were exploited to achieve single bayberry fruit segmentation.Furthermore,with the help of the convex hull theory and fruit shape characteristics,the irregular background interference areas were filtered out,which improved the accuracy of bayberry segmentation performance.The experimental results show that this method can achieve better segmentation of bayberry in complex orchard environment with an accuracy of 97.4%and only takes 0.136 s to calculate once.

Anaphylaxis and generalized urticaria from eating Chinese bayberry fruit

Chinese bayberry Myrica rubra is a very popular fruit in southeastern China.In spite of its wide consumption,no allergies to this fruit have been reported previously.Here we report on a 40-year-old woman suffering from anaphylaxis to Chinese bayberry fruit.Prick-prick skin tests revealed strong reactions to fresh Chinese bayberry fruits as well as to peach,and weaker reactions to some other fruits including apple,melon,and banana.ImmunoCAP analysis revealed identical titers of specific IgE(4.3 kU A /L) to peach extract and its lipid transfer protein(LTP,rPru p 3),which was confirmed by detection of a 9 kD band following immunoblotting.Immunoblot analysis with Chinese bayberry extract gave bands of 22,45,and 90 kD,but no 9 kD band was recognized.There was also no evidence of LTP recognition for loquat(36 kD) or melon(24 kD).This first report of a severe allergic reaction to Chinese bayberry fruit in a patient with LTP-mediated peach allergy indicates that other as yet unidentified non-pollen related fruit allergens are involved in this new severe fruit allergy.

Highly active Pd-Fe/α-Al_(2)O_(3) catalyst with the bayberry tannin as chelating promoter for CO oxidative coupling to diethyl oxalate

A novel Pd-Fe/α-Al_(2)O_(3) catalyst was synthesized by incipient-wetness impregnation method with bayberry tannin as chelating promoter and commercial hollow column Raschig ring a-Al_(2)O_(3) as support for the synthesis of diethyl oxalate from CO and ethyl nitrite.A variety of characterization techniques including N2 physical adsorption,optical microscopy,scanning electron microscopy and energy dispersive system(SEM-EDS),inductively coupled plasma optical emission spectroscopy(ICP-OES),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM),were employed to explore the relationship between the physicochemical properties and activity of catalysts.It indicated that a large number of phenolic hydroxyl groups in bayberry tannin can efficiently anchor the active component Pd,reduce the particle size and make the active Pd as a multi-ring distribution on the commercial a-Al2O3 suppo rt,which we re beneficial to improve the catalytic activity for the production of diethyl oxalate from CO and ethyl nitrite.0.3 wts Pd-Fe/α-Al_(2)O_(3) showed excelle nt catalytic activity and selectivity in a continuous flow,fixed-bed reactor with the loading amount of 10 mL catalysts,Under the mild reaction conditions,the space-time yield of diethyl oxalate was 978 g L^(-1) h^(-1) and CO conversion was 44% with the selectivity to diethyl oxalate of 95.5%.

Effects of fermentation conditions on physicochemical properties and flavor quality of fermented bayberry juice

Probiotic fermented fruit juice could improve intestinal health with better sensory attributes.The effects of fermentation conditions on flavor quality of fermented bayberry juice were compared through microbial viability and sensory evaluation.Fermentation by combined Streptococcus thermophilus(ST)and Lactobaillus acidophilus(L A)resulted in higher microbial viability and sensory evaluation scores.The fermentation con-ditions were optimized by orthogonal experimental design and Technique for Order Preference by Similarity to an Ildeal Solution analysis(ST and LA in a mass ratio of 3:1;0.6%(mass concentration)inoculation;fermentation time,48 h,at 37℃;10%(mass concentration)added sucrose).Fermentation under these conditions decreased the anthocyanin content of the juice,maintained the total phenolic content,and slightly de-creased the antioxidant capacity.Fermentation reduced aroma volatiles from 42 in fresh juice to 33,as determined by gas chromatography-mass spectrometry-olfactometry(GC-MS-O),the aldehyde content decreased and the alcohol content increased.Lactic acid fermented bayberry juice by ST and LA produced a beverage with desirable consumer attributes,combining the health benefits of fresh juice and probiotics.

Physiological and molecular characteristics of two ploidy mutants in Myrica rubracv.Dongkui

In this study, two ploidy mutant lines ofMyrica rubra cv. Dongkui （DK） were identiifed and named as DB1 and DB2. The lforal organ, leaf cel structure, ploidy, and number of chromosomes of the two mutants were investigated. Meanwhile, anthocyanin contents at different developmental stages were analyzed, and the Cy-3-glu contents of DB1 and DB2 at the ful ripe stages are signiifcantly higher than that of DK by 27.84 and 23.51%, respectively. Furthermore, 6 RNA libraries at two developmental stages （young fruit stage and ful ripe stage） were built for RNA-Seq. By mapping to the reference database, 28407, 28043, and 28683 genes were detected in the young fruit of DB1, DB2, and DK, respectively, while 28040, 22256, and 27351 genes were detected in the ful ripe stage, respectively. There were 281 differentialy expressed genes between DB1 and DK, with 123 and 158 genes up-regulated and down-regulated, respectively, and 47 differentialy expressed genes between DB2 and DK, of which 8 and 39 genes were up-regulated and down-regulated. Using real-time PCR, the expression levels of the eight functional genes at different developmental stages of the fruit were also analyzed. These comprehensive analyses showed that both mutants are different from DK, which is the result of natural doubling of ploidy, thereby generating a pleiotropic effect. As we known, it is the ifrst report to study the relationship between bayberry ploidy alterations and genes involved in regulation of fruit mutations, which wil help to identify the morphological and cytological characteristics ofM. rubragermplasm, and provide a theoretical basis and technical support for genetic improvement and creation of breeding resources.