A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mann...A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mannanase genes by RT-PCR. Sequence analysis showed that MaMAN cDNA encompassed a 1 085 bp open-reading frame （ORF）, encoding a predicted polypeptide of 395 amino acids. Alignment of the deduced amino acid sequence of MaMAN and other putative β-mannanases showed that MaMAN has an identity of 86, 70, 69, 54, and 57%, respectively, to β-mannanases from tomato, lettuce, arabidopsis, carrot and oryza sativa. The catalytic residues： Asn203, Glu204, Glu318 and the active site residues： Arg86, His277, Tyr279, and Trp360, which were strictly conserved in the glycoside hydrolase family 5 to which all β-mannanases belonged, were found in MaMAN. Semi-quantitative RT-PCR revealed that the level of MaMAN transcript in the pulp increased during banana fruit ripening, suggesting that MaMAN was likely to be involved highly in banana fruit softening.展开更多
Banana is an edible fruit and is herbaceous flowering plant belonging to the genus Musa and the family Musaceae.Banana is also eaten as cooked vegetable(and is then called plantains).All the edible banana fruits are s...Banana is an edible fruit and is herbaceous flowering plant belonging to the genus Musa and the family Musaceae.Banana is also eaten as cooked vegetable(and is then called plantains).All the edible banana fruits are seedless(parthenocarpic)and belong to two main species,Musa acuminata Colla and Musa balbisiana Colla.The hybrid from these two species Musa x paradisiaca L.is also available nowadays.Although banana is native to Indomalaya and Australia,Papua New Guinea was the first to domesticate this fruit.Banana has now spread to almost 135 countries around the world.As per 2016 data,nearly 28 per cent of the total world’s banana production comes from India and China.Cavendish group banana,being the main export item from the banana-exporting countries,usually refers to soft,sweet,and dessert banana in the Western countries,but the plantain bananas have firm,starchy fruit which is suitable for cooking as a vegetable.Banana is known to be rich not only in carbohydrates,dietary fibres,certain vitamins and minerals,but is also rich in many health-promoting bioactive phytochemicals.General composition including various bioactives and their health contributions has been reviewed in this paper.展开更多
Banana fruit（Musa,AAA group,cv.Brazil） peel fails to fully degreen but the pulp ripens normally at temperatures above24°C.This abnormal ripening,known as green-ripening,does not occur in plantains（Musa,ABB gro...Banana fruit（Musa,AAA group,cv.Brazil） peel fails to fully degreen but the pulp ripens normally at temperatures above24°C.This abnormal ripening,known as green-ripening,does not occur in plantains（Musa,ABB group,cv.Dajiao）.Based on the fact that un-completely yellowing was also observed for bananas in poorly ventilated atmospheres,in the present study,the effect of high CO2 with regular O2（21%） on banana ripening was investigated along with that on plantains at20℃.The results showed that high CO2 conferred different effects on the color changing of bananas and plantains.After6 d ripening in 20%CO2,plantains fully yellowed,while bananas retained high chlorophyll content and stayed green.In contrast to the differentiated color changing patterns,the patterns of the softening,starch degradation and soluble sugar accumulation in the pulp of 20%CO2 treated bananas and plantains displayed similarly as the patterns in the fruits ripening in regular air,indicating that the pulp ripening was not inhibited by 20%CO2,and the abnormal ripening of bananas in 20%CO2 can be considered as green ripening.Similar expression levels of chlorophyll degradation related genes,SGR,NYC and PaO,were detected in the peel of the control and treated fruits,indicating that the repressed degreening in 20%CO2treated bananas was not due to the down-regulation of the chlorophyll degradation related genes.Compared to the effect on plantains,20%CO2 treatment delayed the decline in the chlorophyll florescence（F√F_m values and in the mRNA levels of a gene coding small subunit of Rubisco（SSU）,and postponed the disruption of the ultrastructure of chloroplast in the peel tissue of bananas,indicating that the senescence of the green cells in the exocarp layer was delayed by 20%CO2,to more extent in bananas than in plantains.High CO2 reduced the ethylene production and the expression of the related biosynthesis gene,ACS,but elevated the respiration rates in both cultivars.The up-regulation of the expression of anaerobic respiration pathway genes,ADH and PDC,might be responsible for the subtle effect of high CO2 on the pulp ripening.Taken together,the atmosphere of high CO2 and regular O2,delayed the senescence of the green cells in the exocarp layer of the banana peel,but conferred no obvious inhibition on the pulp ripening,leading to a distinct green-ripening that was different from the phenomenon induced by high temperatures.展开更多
Fruit wastes which are perishable pose a big problem to pollution monitoring agencies;however these problems can be reduced by utilizing the high value compounds present in the food waste. Banana peels contain a reaso...Fruit wastes which are perishable pose a big problem to pollution monitoring agencies;however these problems can be reduced by utilizing the high value compounds present in the food waste. Banana peels contain a reasonable number of antioxidant compounds such as gallocatechin and dopamine. This paper investigates the anti-oxidant potential of two different varieties of Banana peels (Dwarf cavandish and Musa omini). The peels were extracted with two different solvents (Methanol and Ethanol) using the soxhlet extractor. The results show that ethanolic extracts have higher phenolics and flavonoid contents (336.83 - 383.83 mgGAE/100g, 242.83 - 252.82 mgRutin/100g) compared to the methanolic extracts of the same banana varieties (299.42 - 344 mgGAE/100g, 240.77 - 241.23 mgRutin/100g). However methanolic extracts exhibit higher DPPH Antioxidants Activity (30.82% - 51.66%) compared to ethanolic extracts (25.44% - 30.27%). This implies that antioxidative compounds other than phenolics and flavonoids were also involved in inhibiting the DPPH Radicals. It was also observed that at any concentration between 0.5 - 2.5 mg, ethanol extracts of both dwarf cavandish and musa omini had higher reducing power than the other two varieties.展开更多
Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB,Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better s...Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB,Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better sugar-acid blend. However,the traditional Fenjiao variety is susceptible to banana Fusarium wilt,has a high plant height( over 5. 0 m),and farmers lack large-scale planting techniques.Based on the traditional Fenjiao variety,we selected‘Refen 1’variety through mutagenesis technology,which has low temperature resistance,suitable to marginal soils and relatively low plant height( 3. 2-4. 0 m). This paper mainly introduces the major techniques of propagation,cultivation,and post-harvest stages of‘Refen 1’banana,including the selection of explant materials,treatment,disinfection,initial culture,nursery hardening of in vitro-produced banana plants,and transplant of tissue culture seedlings. The major points of the cultivation technology include banana plantation selection and preparation,planting methods,irrigation and fertilizer management,pruning and retaining,and prevention and control of plant diseases and insect pests.展开更多
利用SMART(switching mechanismat5’end of RNA transcript)技术,提取果实少量总RNA,经15-25轮LD-PCR扩增获得全长ds-cDNA,构建了海南主栽的食用香蕉巴西蕉(Musa AAA Group Cavendish)果实的cDNA文库。所构建的文库容量为5×106Pfu...利用SMART(switching mechanismat5’end of RNA transcript)技术,提取果实少量总RNA,经15-25轮LD-PCR扩增获得全长ds-cDNA,构建了海南主栽的食用香蕉巴西蕉(Musa AAA Group Cavendish)果实的cDNA文库。所构建的文库容量为5×106Pfuml-1,重组率93%。利用此cDNA文库,采用96孔板PCR法筛选香蕉Actin2基因,测序结果显示,序列全长1723bp,编码区长1134bp,编码378个氨基酸,与蝴蝶兰Actin2基因序列同源率达83%,已递交GenBank,接受号692696。展开更多
文摘A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mannanase genes by RT-PCR. Sequence analysis showed that MaMAN cDNA encompassed a 1 085 bp open-reading frame （ORF）, encoding a predicted polypeptide of 395 amino acids. Alignment of the deduced amino acid sequence of MaMAN and other putative β-mannanases showed that MaMAN has an identity of 86, 70, 69, 54, and 57%, respectively, to β-mannanases from tomato, lettuce, arabidopsis, carrot and oryza sativa. The catalytic residues： Asn203, Glu204, Glu318 and the active site residues： Arg86, His277, Tyr279, and Trp360, which were strictly conserved in the glycoside hydrolase family 5 to which all β-mannanases belonged, were found in MaMAN. Semi-quantitative RT-PCR revealed that the level of MaMAN transcript in the pulp increased during banana fruit ripening, suggesting that MaMAN was likely to be involved highly in banana fruit softening.
文摘Banana is an edible fruit and is herbaceous flowering plant belonging to the genus Musa and the family Musaceae.Banana is also eaten as cooked vegetable(and is then called plantains).All the edible banana fruits are seedless(parthenocarpic)and belong to two main species,Musa acuminata Colla and Musa balbisiana Colla.The hybrid from these two species Musa x paradisiaca L.is also available nowadays.Although banana is native to Indomalaya and Australia,Papua New Guinea was the first to domesticate this fruit.Banana has now spread to almost 135 countries around the world.As per 2016 data,nearly 28 per cent of the total world’s banana production comes from India and China.Cavendish group banana,being the main export item from the banana-exporting countries,usually refers to soft,sweet,and dessert banana in the Western countries,but the plantain bananas have firm,starchy fruit which is suitable for cooking as a vegetable.Banana is known to be rich not only in carbohydrates,dietary fibres,certain vitamins and minerals,but is also rich in many health-promoting bioactive phytochemicals.General composition including various bioactives and their health contributions has been reviewed in this paper.
基金supported by the National Key Basic Research Program of China(2013CB127105)the National Natural Science Foundation of China(31272214)
文摘Banana fruit（Musa,AAA group,cv.Brazil） peel fails to fully degreen but the pulp ripens normally at temperatures above24°C.This abnormal ripening,known as green-ripening,does not occur in plantains（Musa,ABB group,cv.Dajiao）.Based on the fact that un-completely yellowing was also observed for bananas in poorly ventilated atmospheres,in the present study,the effect of high CO2 with regular O2（21%） on banana ripening was investigated along with that on plantains at20℃.The results showed that high CO2 conferred different effects on the color changing of bananas and plantains.After6 d ripening in 20%CO2,plantains fully yellowed,while bananas retained high chlorophyll content and stayed green.In contrast to the differentiated color changing patterns,the patterns of the softening,starch degradation and soluble sugar accumulation in the pulp of 20%CO2 treated bananas and plantains displayed similarly as the patterns in the fruits ripening in regular air,indicating that the pulp ripening was not inhibited by 20%CO2,and the abnormal ripening of bananas in 20%CO2 can be considered as green ripening.Similar expression levels of chlorophyll degradation related genes,SGR,NYC and PaO,were detected in the peel of the control and treated fruits,indicating that the repressed degreening in 20%CO2treated bananas was not due to the down-regulation of the chlorophyll degradation related genes.Compared to the effect on plantains,20%CO2 treatment delayed the decline in the chlorophyll florescence（F√F_m values and in the mRNA levels of a gene coding small subunit of Rubisco（SSU）,and postponed the disruption of the ultrastructure of chloroplast in the peel tissue of bananas,indicating that the senescence of the green cells in the exocarp layer was delayed by 20%CO2,to more extent in bananas than in plantains.High CO2 reduced the ethylene production and the expression of the related biosynthesis gene,ACS,but elevated the respiration rates in both cultivars.The up-regulation of the expression of anaerobic respiration pathway genes,ADH and PDC,might be responsible for the subtle effect of high CO2 on the pulp ripening.Taken together,the atmosphere of high CO2 and regular O2,delayed the senescence of the green cells in the exocarp layer of the banana peel,but conferred no obvious inhibition on the pulp ripening,leading to a distinct green-ripening that was different from the phenomenon induced by high temperatures.
文摘Fruit wastes which are perishable pose a big problem to pollution monitoring agencies;however these problems can be reduced by utilizing the high value compounds present in the food waste. Banana peels contain a reasonable number of antioxidant compounds such as gallocatechin and dopamine. This paper investigates the anti-oxidant potential of two different varieties of Banana peels (Dwarf cavandish and Musa omini). The peels were extracted with two different solvents (Methanol and Ethanol) using the soxhlet extractor. The results show that ethanolic extracts have higher phenolics and flavonoid contents (336.83 - 383.83 mgGAE/100g, 242.83 - 252.82 mgRutin/100g) compared to the methanolic extracts of the same banana varieties (299.42 - 344 mgGAE/100g, 240.77 - 241.23 mgRutin/100g). However methanolic extracts exhibit higher DPPH Antioxidants Activity (30.82% - 51.66%) compared to ethanolic extracts (25.44% - 30.27%). This implies that antioxidative compounds other than phenolics and flavonoids were also involved in inhibiting the DPPH Radicals. It was also observed that at any concentration between 0.5 - 2.5 mg, ethanol extracts of both dwarf cavandish and musa omini had higher reducing power than the other two varieties.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-31-02)Key R&D project in Hainan Province(ZDYF2019060)Agricultural Science and Technology Innovation Program of CAAS "Evaluation and Regulation of Nutritional Quality of Major Agricultural Products"
文摘Banana is one of the most important crops in tropical and subtropical regions of China. Fenjiao( Musa Spp. ABB,Pisang Awak subgroup) has been grown by small scale famers because of its stable market price and better sugar-acid blend. However,the traditional Fenjiao variety is susceptible to banana Fusarium wilt,has a high plant height( over 5. 0 m),and farmers lack large-scale planting techniques.Based on the traditional Fenjiao variety,we selected‘Refen 1’variety through mutagenesis technology,which has low temperature resistance,suitable to marginal soils and relatively low plant height( 3. 2-4. 0 m). This paper mainly introduces the major techniques of propagation,cultivation,and post-harvest stages of‘Refen 1’banana,including the selection of explant materials,treatment,disinfection,initial culture,nursery hardening of in vitro-produced banana plants,and transplant of tissue culture seedlings. The major points of the cultivation technology include banana plantation selection and preparation,planting methods,irrigation and fertilizer management,pruning and retaining,and prevention and control of plant diseases and insect pests.
文摘利用SMART(switching mechanismat5’end of RNA transcript)技术,提取果实少量总RNA,经15-25轮LD-PCR扩增获得全长ds-cDNA,构建了海南主栽的食用香蕉巴西蕉(Musa AAA Group Cavendish)果实的cDNA文库。所构建的文库容量为5×106Pfuml-1,重组率93%。利用此cDNA文库,采用96孔板PCR法筛选香蕉Actin2基因,测序结果显示,序列全长1723bp,编码区长1134bp,编码378个氨基酸,与蝴蝶兰Actin2基因序列同源率达83%,已递交GenBank,接受号692696。
