Protoplasts of embryogenic suspension cells of loblolly pine (Pinus taeda L).were isolated at exponential growth stage.Influences of various concentrations of basal medium,levels of BA,and concentrations of inositol ...Protoplasts of embryogenic suspension cells of loblolly pine (Pinus taeda L).were isolated at exponential growth stage.Influences of various concentrations of basal medium,levels of BA,and concentrations of inositol on the differentiation of embryonal suspensor mass (ESM),early stage somatic embryos (ESE) ,and lae stage somatic embryos (LSE) were investigated .A study of the effect of various concentrations of LP basal medium sowed that the optimal basal medium concentration of ESM,ESE,and LSE differentiation was 1.25 LP medium.The effects of various levels of BA and inositol showed that the optimal concentrations of BA for the formation of ESM,ESE and LSE were 4 mg/L ,2mg/L and 1mg/L,respectively ,and the optimal concentrations of inositol for the ESM ,ESE and LSM formation were 400mg/L,800mg/L and 1,200mg/L,respectively.展开更多
Gracilariopsis lemaneiformis is a commercially exploited alga. Its filaceous thallus can be divided into three parts, holdfast, middle segment and tip. The growth and branch forming trend and agar content of these thr...Gracilariopsis lemaneiformis is a commercially exploited alga. Its filaceous thallus can be divided into three parts, holdfast, middle segment and tip. The growth and branch forming trend and agar content of these three parts were analyzed, respectively, in this study. The results showed that the tip had the highest growth rate and branched most, although it was the last part with branch forming ability. The holdfast formed branches earliest but slowly. Holdfast had the highest agar content. We also assessed the difference in protoplast formation and regeneration among three parts. The middle segment displayed the shortest enzymolysis time and the highest protoplast yield; whereas the tip had the strongest vitality of protoplasts formation. Juvenile plants were only obtained from the protoplasts generated from the tip. These results suggested that the differentiation and function of G. lemaneiformis was different.展开更多
The term ＂biogenic amines＂ defines decarboxylation products such as histamine, putrescine, serotonin, tyramine, phenylethylamine, tryptamine and also aliphatic polyamines. They can be detected in both raw and proces...The term ＂biogenic amines＂ defines decarboxylation products such as histamine, putrescine, serotonin, tyramine, phenylethylamine, tryptamine and also aliphatic polyamines. They can be detected in both raw and processed foods. In the recent years, there is a great interest in biogenic amines as they are associated with quality, safety and freshness of some foods, particularly fermented foods. The presence of biogenic amines in foods can also be used as an indicator of hygienic quality. Biogenic amines also cause health hazards due to their toxic effects especially in sensitive individuals. It is therefore important to control and reduce the biogenic amines. The reduction can be brought about by the use of high pressure, irradiation, packaging, additives, starter cultures and by reduction of decarboxylase activity and temperature. This review summarizes the significance, function, occurrence and formation of biogenic amines in different foods and their reduction by different methods.展开更多
The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. ...The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. Compared with As-grown Mg:Mn:Fe:LiNbO 3, the absorption edge in UV-Vis. absorption spectrum of the oxidized sample and the reduced shifts to the violet and the red, respectively. Reduction increases the absorption of crystals in visible light region. In two-wave coupling experiments, the writing time, maximum diffraction efficiency and the erasure time of crystal samples in the same conditions are determined. The results indicate that oxidation and reduction disposing has great effect on the holographic recording properties of these crystals. The reduced crystal exhibits the fastest response time of 160 s among the crystal series. The mechanism of post-disposing effect on the holographic recording properties of Mg:Mn:Fe:LiNbO 3 crystals are investigated.展开更多
文摘Protoplasts of embryogenic suspension cells of loblolly pine (Pinus taeda L).were isolated at exponential growth stage.Influences of various concentrations of basal medium,levels of BA,and concentrations of inositol on the differentiation of embryonal suspensor mass (ESM),early stage somatic embryos (ESE) ,and lae stage somatic embryos (LSE) were investigated .A study of the effect of various concentrations of LP basal medium sowed that the optimal basal medium concentration of ESM,ESE,and LSE differentiation was 1.25 LP medium.The effects of various levels of BA and inositol showed that the optimal concentrations of BA for the formation of ESM,ESE and LSE were 4 mg/L ,2mg/L and 1mg/L,respectively ,and the optimal concentrations of inositol for the ESM ,ESE and LSM formation were 400mg/L,800mg/L and 1,200mg/L,respectively.
基金supported by the Twelfth Five-Year Plan in National Science and Technology for the Rural Development in China (2012AA10A411)Public Welfare Project of Ministry of Agriculture of China (200903030)
文摘Gracilariopsis lemaneiformis is a commercially exploited alga. Its filaceous thallus can be divided into three parts, holdfast, middle segment and tip. The growth and branch forming trend and agar content of these three parts were analyzed, respectively, in this study. The results showed that the tip had the highest growth rate and branched most, although it was the last part with branch forming ability. The holdfast formed branches earliest but slowly. Holdfast had the highest agar content. We also assessed the difference in protoplast formation and regeneration among three parts. The middle segment displayed the shortest enzymolysis time and the highest protoplast yield; whereas the tip had the strongest vitality of protoplasts formation. Juvenile plants were only obtained from the protoplasts generated from the tip. These results suggested that the differentiation and function of G. lemaneiformis was different.
文摘The term ＂biogenic amines＂ defines decarboxylation products such as histamine, putrescine, serotonin, tyramine, phenylethylamine, tryptamine and also aliphatic polyamines. They can be detected in both raw and processed foods. In the recent years, there is a great interest in biogenic amines as they are associated with quality, safety and freshness of some foods, particularly fermented foods. The presence of biogenic amines in foods can also be used as an indicator of hygienic quality. Biogenic amines also cause health hazards due to their toxic effects especially in sensitive individuals. It is therefore important to control and reduce the biogenic amines. The reduction can be brought about by the use of high pressure, irradiation, packaging, additives, starter cultures and by reduction of decarboxylase activity and temperature. This review summarizes the significance, function, occurrence and formation of biogenic amines in different foods and their reduction by different methods.
基金The subject has been supported by Chinese National Advanced Technology 863 Project(Grant No.8632001AA31304)Chinese National 973 Project(Grant No.G19990330).
文摘The congruent tri-doped Mg:Mn:Fe:LiNbO 3 crystal has been grown by Czochralski method. Some crystal samples are reduced in Li 2CO 3 powder at 500 ℃ for 24 hours or oxidized for 10 hours at 1100 ℃ in Nb 2O 5 powder. Compared with As-grown Mg:Mn:Fe:LiNbO 3, the absorption edge in UV-Vis. absorption spectrum of the oxidized sample and the reduced shifts to the violet and the red, respectively. Reduction increases the absorption of crystals in visible light region. In two-wave coupling experiments, the writing time, maximum diffraction efficiency and the erasure time of crystal samples in the same conditions are determined. The results indicate that oxidation and reduction disposing has great effect on the holographic recording properties of these crystals. The reduced crystal exhibits the fastest response time of 160 s among the crystal series. The mechanism of post-disposing effect on the holographic recording properties of Mg:Mn:Fe:LiNbO 3 crystals are investigated.
