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.

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.

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.

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.

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.