Curing of freshly harvested yams (Dioscorea spp.) is a process for wounded yams during harvest to heal. In this work the effectiveness of straw, polypropylene and jute sack on curing of seven key farmers’ yam varieti...Curing of freshly harvested yams (Dioscorea spp.) is a process for wounded yams during harvest to heal. In this work the effectiveness of straw, polypropylene and jute sack on curing of seven key farmers’ yam varieties over a duration of 7, 14 and 21 days was studied. Seven key farmers’ yam varieties identified as Pona, Lariboko, Dente, Mutwumudoo, Serwah belonging to D. rotundata, Matches and Akaba belonging to D. alata were studied under different curing treatments. The percentage weight loss of yam tubers varied among the treatments over curing period. Curing under jute sack showed all yam varieties had weight losses less than 2.0%, within 7 days of curing. Five different varieties had weight loss less than 2.0% except Dente under the straw treatment. Mutwumudoo variety showed the highest water loss (8.4%) for polypropylene sheet and 6.9% for Lariboko in the control treatment. During 7 days curing the control and polypropylene treatment did not support yam curing. After 14 days of curing of tubers, similar tends were observed as in 7 days curing. After 14 days of curing under jute sack, percentage weight loss of the tubers ranges from 2.0% - 3.7%. In the straw treatment, the percentage weight loss ranges between 1.0% - 4.7% in all other varieties except Dente (D. rotundata) (8.2%). Polypropylene sheet treatment showed the highest percentage weight loss in Mutwumudoo variety (18.4%). A similar trend was observed for the yam tubers cured for 21days as percentage weight loss of tubers under jute sacks was 2.5 – 9.8%. Curing temperature and humidity ranged between 27°C - 40°C and 87% - 100% rh for yam tubers under the three different treatments of polypropylene, jute and straw. However, the control treatment recorded lower humidity of 60% - 80% rh. Curing material, duration, climatic conditions and yam varieties influenced curing and Serwah variety, which is a D. rotundata is the best bet yam variety to cure under jute sack for 7, 14 and 21 days of curing.展开更多
Climate change poses an important constraint to agricultural sector and food security in tropical African countries dominated by rain-fed agriculture. This research focuses on the effects of climate variability on yam...Climate change poses an important constraint to agricultural sector and food security in tropical African countries dominated by rain-fed agriculture. This research focuses on the effects of climate variability on yam production in central and northern Benin. Daily climate data such as temperatures, precipitation, potential evapotranspiration, relative humidity and insolation from 1981 to 2016 were collected at the direction of METEO-Benin. A survey was then conducted with 351 producers to collect their perceptions of the effect of climate variability on the yams production. Descriptive statistics, principal component analysis (PCA) followed by trend analyses, Lamb index calculations and the agro-climatic stress index were carried out. The distribution of rain during the yam cycle (91.5% of those surveyed), the ambient temperature (84.9%), insolation (83.5%), the amount of rainwater that fell during the rainy season (82.2%) and the harmattan (53.3%) are perceived by sociolinguistic groups as climatic factors affecting the growth, the tuberization and yield of yams according to the producers. The results indicate an upward trend in temperature over the period 2001 to 2016 in the transition zone (28.4<span style="white-space:nowrap;">°</span>C) and in the Northeast (27.76<span style="white-space:nowrap;">°</span>C) and over the period from 2001 to 2011 in the North-West of Benin (27.71<span style="white-space:nowrap;">°</span>C), where the average annual temperature during these periods is higher than normal (27.82<span style="white-space:nowrap;">°</span>C in the center, 27.44<span style="white-space:nowrap;">°</span>C in the Northeast and 27.42<span style="white-space:nowrap;">°</span>C to the northwest). This research also shows an instability of the rains with a regular decrease in the rainfall in the Centre and the North-East of the country. The agro-climatic stress index (ISA) and above all the annual rainfall constitute the main climatic factors which determine the yield of yam in the various growing areas in Benin. The average annual temperature and that of January in the transition zone, the rains of January and April in the North-East zone and the relative humidity in the North-West zone also probability determine the yield of the yam.展开更多
The effects of yam powder(YP)on the functional properties of wheat flour noodles were investigated to improve the nutritional value of noodles and provide a scientific basis for YP application in flour products.Using ...The effects of yam powder(YP)on the functional properties of wheat flour noodles were investigated to improve the nutritional value of noodles and provide a scientific basis for YP application in flour products.Using wheat flour as the main ingredient,the effects of different YP substitution ratios(0,5%,10%,15%,20%,and 25%)on polyphenolic content,2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical scavenging rate,and starch digestibility of the prepared noodles were analyzed in vitro.Additionally,the effects of YP water-soluble extracts,wheat flour noodles,and YP-enriched noodles(hereinafter,YP noodles)on inflammatory factors in vascular smooth muscle cells(VSMCs)treated by H_(2)O_(2)(100μM)were investigated.The results showed that YP had a substantial effect on polyphenolic content and DPPH free radical scavenging rate of wheat flour noodles,significantly increasing both values compared with those of the control group(P<0.05).The polyphenolic content reached a maximum of 2.17 mg/g in noodles with 20%YP substitution,whereas DPPH free radical scavenging rate reached a maximum of 42.10%in noodles with 25%YP substitution.With an increase in YP amount,both starch hydrolysis rate and rapidly digestible starch content of the noodles decreased gradually,whereas resistant starch content increased significantly.Moreover,50,100,and 200μg/mL of water-soluble YP and YP noodle extracts had no significant effect on the viability of VSMCs,and high concentrations of YP and YP noodle extracts resulted in cell death.Both YP and noodle extracts also reduced the secretion levels of inflammatory factors IL-6 and TNF-α in H_(2)O_(2)-treated VSMCs.Overall,YP addition reduced starch digestibility,increased antioxidative activity,and effectively improved functional quality of noodles.This study provides reference for the research and development of health-benefiting anti-inflammatory foods.展开更多
Bionanocomposite film is produced from renewable and biodegradable natural resources.Although elephant foot yam(EFY)starch(Amorphophallus paeoniifolius)is a promising polymer for bionanocomposite film,the native hydro...Bionanocomposite film is produced from renewable and biodegradable natural resources.Although elephant foot yam(EFY)starch(Amorphophallus paeoniifolius)is a promising polymer for bionanocomposite film,the native hydrophilic properties influence the overall performance characteristics.Incorporating virgin coconut oil(VCO)and monoglyceride as hydrophobic components can improve mechanical properties and reduce permeability while increasing the hydrophobicity of the composite.Therefore,this study aimed to determine the effect of adding VCO and monoglyceride on EFY starch-nanocrystalline film at 3 and 5 wt%concentrations.Experimental tests were conducted to evaluate the physical and mechanical properties,water vapor transmission rate(WVTR),morphology,functional groups,biodegradability,and hydrophobicity.The results showed that the addition of 5 wt%monoglyceride produced optimum outcomes by reducing the WVTR to 3.99 g.m^(−2).h^(−1),increasing the thickness to 0.134 mm and decreasing the solubility to 36.04%.The Universal Testing Machine(UTM)tests showed an elongation of 74.59%,showing excellent elasticity.The Scanning Electron Microscope(SEM)test showed the bonds formed with starch granules,leading to a flatter surface.The Fourier Transform Infrared Spectroscopy(FTIR)test also showed an increase in the wavelength of the C=O groups and a decrease in the O-H groups.The contact angle test processed using image-J showed high hydrophobicity,consequently reducing the biodegradability of bionanocomposite film by the Aspergillus niger fungal degradation test.In conclusion,this study successfully developed bionanocomposite film with enhanced hydrophobicity,elasticity,and barrier properties,highly suitable for protecting food from humid air.The composite holds great potential for further development as an environmentally friendly packaging solution.展开更多
The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bul...The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bulbils was signifi- cantly enhanced with the increase of concentration; they showed a strong scaveng- ing ability against DPPH. and .OH, and the scavenging ability was dose dependent to some extent; the scavenging rates reached 91.15% and 89.06% respectively when the dose reached 4.0 mg/ml; the polysaccharides in yam bulbils significantly educed the blood glucose in model rice, and the hypoglycemic effect of large-dose polysaccharides was more obvious. The polysaccharides in yam bulbils has good antioxidant activity and hypoglycemic effect, which provides a new source for devel- opment of safe and natural food antioxidants and blood sugar-lowering agents.展开更多
The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation....The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation.Integrated with agricultural machinery and agricultural trait,four kinds of machines produced by two factories from Jiangsu and Shandong could complete 10 kinds of main production processes,including rotary tillage,ridging,sowing,intertillage,topdressing,drug delivery,weeding,hilling,vine cutting and harvest.The work efficiency of single machine was 4-5 hm^2/d,and the production pattern got the cost saving and effectiveness increasing in the main yam producing area.The benefit reached over RMB 37500 yuan/hm^2 in special vegetable area.It was simple,feasible and easy to popularize the mechanization cultivation technique.展开更多
[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which wer...[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which were reared with artificial semisynthetic feed added with 10% steamed yam powder.The four groups,the casein（CK） group which was used as the control,the purple yam（PY） group,the Tiegun yam（TY） group and common Huai yam（HY） group,were supplied with feed of equal content of energy,protein and fat.The rats were pair-fed for 56 days to observe changes of relevant nutritional and physiological indices.[Result] There were no significant differences of body weight,food conversion rate and organ indices between rats in PY group and CK group.Mean corpuscular hemoglobin in PY group was significantly lower than that in CK group;hemoglobin showed no significant difference with that in CK group;eosnophils was lower than that in CK group.Low density lipoprotein-cholesterol,total cholesterol and atherogenic index in PY group were lower than that in the other three groups;anti-atherogenic index was the highest among the four groups,while showing no significant difference;triglyceride content was lower than that in CK group.Among the antioxidant indices,the activity of catalase and superoxide dismutase were higher than that in CK group,while malondialdehyde content was lower than that in CK group.[Conclusion] Purple yam showed the trend of reducing the content of blood glucose,total cholesterol,low density lipoprotein-cholesterol,triglyceride,malondialdehyde,and raising the activity of glutathione peroxidase,superoxide dismutase and catalase,thus having certain antioxidative function.展开更多
A 3D structured composite of carbon nanofibers @ MnO2 on copper foil is reported here as a binder free anode of lithium ion batteries, with high capacity, fast charge/discharge rate and good stability. Carbon nanofibe...A 3D structured composite of carbon nanofibers @ MnO2 on copper foil is reported here as a binder free anode of lithium ion batteries, with high capacity, fast charge/discharge rate and good stability. Carbon nanofiber yarns were synthesized directly over copper foil through a floating catalyst method. The growth of carbon nanofiber yarns was significantly enhanced by mechanical polishing of the copper foils, which can be attributed to the increased surface roughness and surface area of the copper foils. MnO2 was then grown over carbon nanofibers through spontaneous reduction of potassium permanganate by the carbon nanofibers. The obtained composites of carbon nanofibers@MnO2 over copper foil were tested as an anode in lithium ion batteries and they show superior electrochemical performance. The initial reversible capacity of carbon nanofibers@MnO2 reaches up to around 998 mAh.g-1 at a rate of 60 mmA.g-l based on the mass of carbon nanofibers and MnO2. The carbon nanofibers @ MnO2 electrodes could deliver a capacity of 630 mAh.g-1 at the beginning and maintain a capacity of 440 mmAh.g-1 after 105 cycles at a rate of 600 mA.g-~. The high initial capacity can be attributed to the presence of porous carbon nanofiber yarns which have good electrical conductivity and the MnO2 thin film which makes the entire materials electrochemically active. The high cyclic stability of carbon nanofibers@MnO2 can be ascribed to the MnO2 thin film which can accommodate the volume expansion and shrinking during charge and discharge and the good contact of carbon nanofibers with MnO2 and copper foil.展开更多
For traditional cultivation of Chinese yam, it is necessary to dig a deep trench duringsowing and harvest, wasting labor and time, and Chinese yam requires good quality of cultivated land, causing serious impact on th...For traditional cultivation of Chinese yam, it is necessary to dig a deep trench duringsowing and harvest, wasting labor and time, and Chinese yam requires good quality of cultivated land, causing serious impact on the development of yam industry due to the competition with food production. Yam no-tillage ecological cul- ture techniques, combined with advantage of yam directional tuberization, could en- able the cultivation of yam inlow-production field, barren hills and sloping field, forest land and other non-staple food land and thus could promote farmers＇ income as well as improving the ecological environment.展开更多
Photo-oxidative degradation of polypropylene/clay multifilament yarns containing different amounts of clay was investigated. These samples and pure polypropylene （PP） multifilametns were exposed to long wavelength r...Photo-oxidative degradation of polypropylene/clay multifilament yarns containing different amounts of clay was investigated. These samples and pure polypropylene （PP） multifilametns were exposed to long wavelength radiations （λ〉 300 nm） under atmospheric condition of constant temperature and relative humidity. The photo-oxidative stability was studied using FTIR spectroscopy, tensile testing and microscopy. The results indicate that the addition of clay particles decreases the stability of PP/clay composites to photo-oxidative degradation according to comparison with pure PP. From FTIR study and tensile properties, it was also found that the multifilaments with higher clay loading reveals a faster loss of mechanical properties, higher photo-oxidative product formation and more reduction in the induction time of photo-oxidation. Moreover, the crack formation on surface of irradiated filaments corresponds well to the conclusions in tensile properties and FTIR characterization.展开更多
More and more composite yarns of filament and wool staple fiber have been applied to develop the new type of fabrics. However, the great difference in yarn structures between the composite yarns and conventional stapl...More and more composite yarns of filament and wool staple fiber have been applied to develop the new type of fabrics. However, the great difference in yarn structures between the composite yarns and conventional staple yarns does affect the properties of yarns and fabrics. In this paper, it has been studied that the differences of the composite yarn properties of tensile, bending rigidity, torsional rigidity, the hairiness and irregularity etc.展开更多
The effect of varied processing variables （yam slice thickness, drying temperatures and type of drying） were investigated to determine their effects on the proximate and some functional properties of yam flour. The ...The effect of varied processing variables （yam slice thickness, drying temperatures and type of drying） were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values （6.20%-6.87%） followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.展开更多
The aim of this study is to produce large quantities of yam tubers in the field from seed tubers derived from vitroplants regenerated from aerial stem cuttings and farmers’ tuber seeds. Seed tubers from ten yam culti...The aim of this study is to produce large quantities of yam tubers in the field from seed tubers derived from vitroplants regenerated from aerial stem cuttings and farmers’ tuber seeds. Seed tubers from ten yam cultivars, including five from Dioscorea alata (cDa083, cDa053, cDa115, cDa150 and cDa266) and five from Dioscorea cayenensis-rotundata (cDr015, cDr027, cDr150, cDr206 and cDr148) with distinct agro-morphological characteristics, were used as material. A completely randomized block design with 3 replications was used. In each block, all cultivars and seed types were represented. When put into cultivation, the tubers produced by the vitroplants all germinated and gave 100% healthy plants, compared with 86% to 100% healthy plants for the seed tubers produced by the farmers. Yields per hectare ranged from 10 to 25 tonnes for seed tubers produced by in vitro plants, and from 4 to 9 tons for seed tubers produced by farmers. Seed tubers from vitroplants can therefore be recommended to farmers as a solution to the problem of seed tuber unavailability.展开更多
文摘Curing of freshly harvested yams (Dioscorea spp.) is a process for wounded yams during harvest to heal. In this work the effectiveness of straw, polypropylene and jute sack on curing of seven key farmers’ yam varieties over a duration of 7, 14 and 21 days was studied. Seven key farmers’ yam varieties identified as Pona, Lariboko, Dente, Mutwumudoo, Serwah belonging to D. rotundata, Matches and Akaba belonging to D. alata were studied under different curing treatments. The percentage weight loss of yam tubers varied among the treatments over curing period. Curing under jute sack showed all yam varieties had weight losses less than 2.0%, within 7 days of curing. Five different varieties had weight loss less than 2.0% except Dente under the straw treatment. Mutwumudoo variety showed the highest water loss (8.4%) for polypropylene sheet and 6.9% for Lariboko in the control treatment. During 7 days curing the control and polypropylene treatment did not support yam curing. After 14 days of curing of tubers, similar tends were observed as in 7 days curing. After 14 days of curing under jute sack, percentage weight loss of the tubers ranges from 2.0% - 3.7%. In the straw treatment, the percentage weight loss ranges between 1.0% - 4.7% in all other varieties except Dente (D. rotundata) (8.2%). Polypropylene sheet treatment showed the highest percentage weight loss in Mutwumudoo variety (18.4%). A similar trend was observed for the yam tubers cured for 21days as percentage weight loss of tubers under jute sacks was 2.5 – 9.8%. Curing temperature and humidity ranged between 27°C - 40°C and 87% - 100% rh for yam tubers under the three different treatments of polypropylene, jute and straw. However, the control treatment recorded lower humidity of 60% - 80% rh. Curing material, duration, climatic conditions and yam varieties influenced curing and Serwah variety, which is a D. rotundata is the best bet yam variety to cure under jute sack for 7, 14 and 21 days of curing.
文摘Climate change poses an important constraint to agricultural sector and food security in tropical African countries dominated by rain-fed agriculture. This research focuses on the effects of climate variability on yam production in central and northern Benin. Daily climate data such as temperatures, precipitation, potential evapotranspiration, relative humidity and insolation from 1981 to 2016 were collected at the direction of METEO-Benin. A survey was then conducted with 351 producers to collect their perceptions of the effect of climate variability on the yams production. Descriptive statistics, principal component analysis (PCA) followed by trend analyses, Lamb index calculations and the agro-climatic stress index were carried out. The distribution of rain during the yam cycle (91.5% of those surveyed), the ambient temperature (84.9%), insolation (83.5%), the amount of rainwater that fell during the rainy season (82.2%) and the harmattan (53.3%) are perceived by sociolinguistic groups as climatic factors affecting the growth, the tuberization and yield of yams according to the producers. The results indicate an upward trend in temperature over the period 2001 to 2016 in the transition zone (28.4<span style="white-space:nowrap;">°</span>C) and in the Northeast (27.76<span style="white-space:nowrap;">°</span>C) and over the period from 2001 to 2011 in the North-West of Benin (27.71<span style="white-space:nowrap;">°</span>C), where the average annual temperature during these periods is higher than normal (27.82<span style="white-space:nowrap;">°</span>C in the center, 27.44<span style="white-space:nowrap;">°</span>C in the Northeast and 27.42<span style="white-space:nowrap;">°</span>C to the northwest). This research also shows an instability of the rains with a regular decrease in the rainfall in the Centre and the North-East of the country. The agro-climatic stress index (ISA) and above all the annual rainfall constitute the main climatic factors which determine the yield of yam in the various growing areas in Benin. The average annual temperature and that of January in the transition zone, the rains of January and April in the North-East zone and the relative humidity in the North-West zone also probability determine the yield of the yam.
基金financial support of the Henan Provincial Science and Technology Research Project(Project No.242102310322)Shangqiu Product Quality Inspection and Testing Center(Project No.2024001).
文摘The effects of yam powder(YP)on the functional properties of wheat flour noodles were investigated to improve the nutritional value of noodles and provide a scientific basis for YP application in flour products.Using wheat flour as the main ingredient,the effects of different YP substitution ratios(0,5%,10%,15%,20%,and 25%)on polyphenolic content,2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical scavenging rate,and starch digestibility of the prepared noodles were analyzed in vitro.Additionally,the effects of YP water-soluble extracts,wheat flour noodles,and YP-enriched noodles(hereinafter,YP noodles)on inflammatory factors in vascular smooth muscle cells(VSMCs)treated by H_(2)O_(2)(100μM)were investigated.The results showed that YP had a substantial effect on polyphenolic content and DPPH free radical scavenging rate of wheat flour noodles,significantly increasing both values compared with those of the control group(P<0.05).The polyphenolic content reached a maximum of 2.17 mg/g in noodles with 20%YP substitution,whereas DPPH free radical scavenging rate reached a maximum of 42.10%in noodles with 25%YP substitution.With an increase in YP amount,both starch hydrolysis rate and rapidly digestible starch content of the noodles decreased gradually,whereas resistant starch content increased significantly.Moreover,50,100,and 200μg/mL of water-soluble YP and YP noodle extracts had no significant effect on the viability of VSMCs,and high concentrations of YP and YP noodle extracts resulted in cell death.Both YP and noodle extracts also reduced the secretion levels of inflammatory factors IL-6 and TNF-α in H_(2)O_(2)-treated VSMCs.Overall,YP addition reduced starch digestibility,increased antioxidative activity,and effectively improved functional quality of noodles.This study provides reference for the research and development of health-benefiting anti-inflammatory foods.
基金funded by an Internal Research Grant of Universitas Padjadjaran,Bandung,Indonesia.
文摘Bionanocomposite film is produced from renewable and biodegradable natural resources.Although elephant foot yam(EFY)starch(Amorphophallus paeoniifolius)is a promising polymer for bionanocomposite film,the native hydrophilic properties influence the overall performance characteristics.Incorporating virgin coconut oil(VCO)and monoglyceride as hydrophobic components can improve mechanical properties and reduce permeability while increasing the hydrophobicity of the composite.Therefore,this study aimed to determine the effect of adding VCO and monoglyceride on EFY starch-nanocrystalline film at 3 and 5 wt%concentrations.Experimental tests were conducted to evaluate the physical and mechanical properties,water vapor transmission rate(WVTR),morphology,functional groups,biodegradability,and hydrophobicity.The results showed that the addition of 5 wt%monoglyceride produced optimum outcomes by reducing the WVTR to 3.99 g.m^(−2).h^(−1),increasing the thickness to 0.134 mm and decreasing the solubility to 36.04%.The Universal Testing Machine(UTM)tests showed an elongation of 74.59%,showing excellent elasticity.The Scanning Electron Microscope(SEM)test showed the bonds formed with starch granules,leading to a flatter surface.The Fourier Transform Infrared Spectroscopy(FTIR)test also showed an increase in the wavelength of the C=O groups and a decrease in the O-H groups.The contact angle test processed using image-J showed high hydrophobicity,consequently reducing the biodegradability of bionanocomposite film by the Aspergillus niger fungal degradation test.In conclusion,this study successfully developed bionanocomposite film with enhanced hydrophobicity,elasticity,and barrier properties,highly suitable for protecting food from humid air.The composite holds great potential for further development as an environmentally friendly packaging solution.
基金Supported by Key Project of Huainan Normal College(2011LK76zd)Youth Fund of Huainan Normal College(2010LK13)~~
文摘The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bulbils was signifi- cantly enhanced with the increase of concentration; they showed a strong scaveng- ing ability against DPPH. and .OH, and the scavenging ability was dose dependent to some extent; the scavenging rates reached 91.15% and 89.06% respectively when the dose reached 4.0 mg/ml; the polysaccharides in yam bulbils significantly educed the blood glucose in model rice, and the hypoglycemic effect of large-dose polysaccharides was more obvious. The polysaccharides in yam bulbils has good antioxidant activity and hypoglycemic effect, which provides a new source for devel- opment of safe and natural food antioxidants and blood sugar-lowering agents.
文摘The new bulk purple yam variety Suyu 2,which had high quality,efficiency and was suitable for production in a highly mechanized cultivation,was bred by special and was suitable for whole-course mechanized cultivation.Integrated with agricultural machinery and agricultural trait,four kinds of machines produced by two factories from Jiangsu and Shandong could complete 10 kinds of main production processes,including rotary tillage,ridging,sowing,intertillage,topdressing,drug delivery,weeding,hilling,vine cutting and harvest.The work efficiency of single machine was 4-5 hm^2/d,and the production pattern got the cost saving and effectiveness increasing in the main yam producing area.The benefit reached over RMB 37500 yuan/hm^2 in special vegetable area.It was simple,feasible and easy to popularize the mechanization cultivation technique.
基金Supported by the Special Fund for Construction of Scientific and Technological Innovation Ability of BAAFS(KJCX201101010-22)~~
文摘[Objective] This study was to explore the effect of purple yam on the nutritional and physiological functions of rats.[Method] Forty SD rats were randomly divided into four groups with ten rats in each group which were reared with artificial semisynthetic feed added with 10% steamed yam powder.The four groups,the casein（CK） group which was used as the control,the purple yam（PY） group,the Tiegun yam（TY） group and common Huai yam（HY） group,were supplied with feed of equal content of energy,protein and fat.The rats were pair-fed for 56 days to observe changes of relevant nutritional and physiological indices.[Result] There were no significant differences of body weight,food conversion rate and organ indices between rats in PY group and CK group.Mean corpuscular hemoglobin in PY group was significantly lower than that in CK group;hemoglobin showed no significant difference with that in CK group;eosnophils was lower than that in CK group.Low density lipoprotein-cholesterol,total cholesterol and atherogenic index in PY group were lower than that in the other three groups;anti-atherogenic index was the highest among the four groups,while showing no significant difference;triglyceride content was lower than that in CK group.Among the antioxidant indices,the activity of catalase and superoxide dismutase were higher than that in CK group,while malondialdehyde content was lower than that in CK group.[Conclusion] Purple yam showed the trend of reducing the content of blood glucose,total cholesterol,low density lipoprotein-cholesterol,triglyceride,malondialdehyde,and raising the activity of glutathione peroxidase,superoxide dismutase and catalase,thus having certain antioxidative function.
基金VISTA-a basic research program funded by Statoil,conducted in close collaboration with The Norwegian Academy of Science and Letters which is gratefully acknowledged
文摘A 3D structured composite of carbon nanofibers @ MnO2 on copper foil is reported here as a binder free anode of lithium ion batteries, with high capacity, fast charge/discharge rate and good stability. Carbon nanofiber yarns were synthesized directly over copper foil through a floating catalyst method. The growth of carbon nanofiber yarns was significantly enhanced by mechanical polishing of the copper foils, which can be attributed to the increased surface roughness and surface area of the copper foils. MnO2 was then grown over carbon nanofibers through spontaneous reduction of potassium permanganate by the carbon nanofibers. The obtained composites of carbon nanofibers@MnO2 over copper foil were tested as an anode in lithium ion batteries and they show superior electrochemical performance. The initial reversible capacity of carbon nanofibers@MnO2 reaches up to around 998 mAh.g-1 at a rate of 60 mmA.g-l based on the mass of carbon nanofibers and MnO2. The carbon nanofibers @ MnO2 electrodes could deliver a capacity of 630 mAh.g-1 at the beginning and maintain a capacity of 440 mmAh.g-1 after 105 cycles at a rate of 600 mA.g-~. The high initial capacity can be attributed to the presence of porous carbon nanofiber yarns which have good electrical conductivity and the MnO2 thin film which makes the entire materials electrochemically active. The high cyclic stability of carbon nanofibers@MnO2 can be ascribed to the MnO2 thin film which can accommodate the volume expansion and shrinking during charge and discharge and the good contact of carbon nanofibers with MnO2 and copper foil.
基金Supported by National Scientific and Technological Special Program(200903022)Science and Technology Development Fund of Guangxi Academy of Agricultural Sciences(2015JM11)~~
文摘For traditional cultivation of Chinese yam, it is necessary to dig a deep trench duringsowing and harvest, wasting labor and time, and Chinese yam requires good quality of cultivated land, causing serious impact on the development of yam industry due to the competition with food production. Yam no-tillage ecological cul- ture techniques, combined with advantage of yam directional tuberization, could en- able the cultivation of yam inlow-production field, barren hills and sloping field, forest land and other non-staple food land and thus could promote farmers＇ income as well as improving the ecological environment.
文摘Photo-oxidative degradation of polypropylene/clay multifilament yarns containing different amounts of clay was investigated. These samples and pure polypropylene （PP） multifilametns were exposed to long wavelength radiations （λ〉 300 nm） under atmospheric condition of constant temperature and relative humidity. The photo-oxidative stability was studied using FTIR spectroscopy, tensile testing and microscopy. The results indicate that the addition of clay particles decreases the stability of PP/clay composites to photo-oxidative degradation according to comparison with pure PP. From FTIR study and tensile properties, it was also found that the multifilaments with higher clay loading reveals a faster loss of mechanical properties, higher photo-oxidative product formation and more reduction in the induction time of photo-oxidation. Moreover, the crack formation on surface of irradiated filaments corresponds well to the conclusions in tensile properties and FTIR characterization.
文摘More and more composite yarns of filament and wool staple fiber have been applied to develop the new type of fabrics. However, the great difference in yarn structures between the composite yarns and conventional staple yarns does affect the properties of yarns and fabrics. In this paper, it has been studied that the differences of the composite yarn properties of tensile, bending rigidity, torsional rigidity, the hairiness and irregularity etc.
文摘The effect of varied processing variables （yam slice thickness, drying temperatures and type of drying） were investigated to determine their effects on the proximate and some functional properties of yam flour. The yam flour was produced with different slice thickness of 1, 1.5, 2.0, 2.5 and 5 cm using both conventional sun drying method and oven drying at temperatures; 40 ~C, 50 ~C, 60 ~C and 70 ~C. The moisture content of all the yam flour samples increased with increasing yam slice thickness, with the samples sun dried having the lowest values （6.20%-6.87%） followed by those dried at 70 ~C and then 60 ~C. The protein content of the yam flour samples increased with increase in slice thickness and decreased with increase in drying temperatures while the fat and the crude fibre of all the yam flour samples decreased with increase in slice thickness. The water absorption capacity of the sun dried yam flour samples decreased with increase in slice thickness while the syneresis value, bulk density and the gel strength increased with increase in slice thickness for all drying temperatures and for sun dried yam flour samples but smaller slice thickness had higher swelling capacity.
文摘The aim of this study is to produce large quantities of yam tubers in the field from seed tubers derived from vitroplants regenerated from aerial stem cuttings and farmers’ tuber seeds. Seed tubers from ten yam cultivars, including five from Dioscorea alata (cDa083, cDa053, cDa115, cDa150 and cDa266) and five from Dioscorea cayenensis-rotundata (cDr015, cDr027, cDr150, cDr206 and cDr148) with distinct agro-morphological characteristics, were used as material. A completely randomized block design with 3 replications was used. In each block, all cultivars and seed types were represented. When put into cultivation, the tubers produced by the vitroplants all germinated and gave 100% healthy plants, compared with 86% to 100% healthy plants for the seed tubers produced by the farmers. Yields per hectare ranged from 10 to 25 tonnes for seed tubers produced by in vitro plants, and from 4 to 9 tons for seed tubers produced by farmers. Seed tubers from vitroplants can therefore be recommended to farmers as a solution to the problem of seed tuber unavailability.
