To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The exp...To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The experiment, comprising of 400 sugarcane genotypes of which 174 were local that were collected from different regional states of Ethiopia and 226 introduced, was laid out in partial balanced lattice design with two replications. Data was collected on cane yield and its components, sugar yield and sugar quality traits. ANOVA, correlation and path coefficient analysis were done. Analysis of variance revealed significant differences (P < 0.01) for all the characters studied. Cane yield showed strong positive and highly significant (P < 0.01) correlation with millable cane number (r = 0.832), single cane weight (r = 0.528), stalk height (r = 0.517) and sugar yield (r = 0.987). There was also positive significant (P = 0.05) correlation of tiller count and cane diameter with cane yield. Path analysis revealed the highest positive direct effect of millable cane number (0.812) on cane yield followed by single cane weight (0.682) and pol percent (0.550). However, stalk diameter and brix percent had considerable negative direct effects and indirect positive effects through single cane weight on cane yield. Therefore, in view of their significant positive association with cane yield, indirect effects of stalk diameter and brix percent via single cane weight should be considered during selection. Genotypes should be selected on the basis of millable cane number, single cane weight and pol percent for getting higher cane and sugar yield.展开更多
The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips an...The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings.展开更多
The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows...The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows(Duroc × Landrace × Jiaxing Black), with an average initial body weight of 62.1 ± 5.0 kg,were randomly allotted to 1 of 3 diets with 6 replicates per treatment for 42 days. The diets comprised a normal diet and the normal diets supplemented with 5 and 25 g/kg SCE. The results showed that SCE supplementation did not affect final body weight of finishing pigs. Dietary SCE supplementation significantly increased(P < 0.05) Longissimus dorsi muscle pH_(24 h),and tended to reduce(P < 0.1) and significantly decreased(P < 0.05) shear force, drip loss, myofiber cross sectional area and lactate dehydrogenase activity at 5 and 25 g/kg, respectively. Meanwhile, dietary SCE treatments significantly decreased(P < 0.05) malonaldehyde content and total superoxide dismutase activity in Longissimus dorsi muscle, and tended to reduce(P < 0.1) malonaldehyde content in serum. Altogether, these data indicate that SCE is an effective feed additive to improve pork meat quality, and the underlying mechanism may be partly due to the improved oxidative stability induced by dietary SCE supplementation.展开更多
In order to investigate the visible-NIR spectral features of the leaves of a sugarcane variety(ROC 22),the spectral reflectance and the chlorophyll content were measured in the laboratory,and their correlations were a...In order to investigate the visible-NIR spectral features of the leaves of a sugarcane variety(ROC 22),the spectral reflectance and the chlorophyll content were measured in the laboratory,and their correlations were analyzed.Prediction models were built eventually.Results showed that the negative correlations with r greater than 0.8 was found in 527-578 nm and 701-731nm between spectral reflectance and chlorophyll content.And the red edge position(REP)was also found having high correlation with chlorophyll content,with the highest r of 0.8442.In order to explore the most sensitive bands for normalized difference vegetation index(NDVI),48471 NDVI values were computed with different wavebands for each sample and their correlations with chlorophyll were also analyzed.The distribution maps of NDVI and its correlations in a two-spectral-dimension space both indicated that the red bands had significant influence than the NIR bands.The suggested sensitive red range was 710-735 nm,especially720-725 nm;and the sensitive NIR range was from 780-850 nm,which had the higher robustness.The chlorophyll predication model with NDVI(725 and 840 nm)in tillering stage had determination coefficients of 0.7386,and was recommended for guiding the subsequent ridging fertilization.展开更多
To obtain the mechanical properties of greenhouse cucumber cane,tensile and shear properties of the greenhouse cucumber cane were studied by using computer-controlled electronic universal testing machine and homemade ...To obtain the mechanical properties of greenhouse cucumber cane,tensile and shear properties of the greenhouse cucumber cane were studied by using computer-controlled electronic universal testing machine and homemade cutting test bench,respectively.Firstly,the root,middle and head of cucumber cane were subjected for tensile tests.The tensile stress-strain curves showed that the root of cumber cane presented the characteristics of plastic material,while the middle and head showed the characteristics of brittle material.The average tensile strength of root,middle and head of fresh cucumber cane were 7.35 MPa,6.30 MPa and 4.68 MPa,respectively.The average elastic modulus of root of fresh cucumber cane was 280.58 MPa,which was much greater than the middle and head with average elastic modulus of 198.81 MPa and 137.22 MPa,respectively.A pendulum impact cutting test-rig and a cutting force measurement system composed of a cantilever weigh sensor,a high frequency DAQ card and motion control card were developed.The cutting mechanical property experiments of different parts of greenhouse cucumber cane were carried out,and the continuous curves of cutting force were measured.The single factor test for cross-sectional area,cutting speed,cutting tool type and manner were analyzed.The results indicated that the peak cutting force increased approximately linearly with the increasing of cutting sectional area,but decreased gradually with the increasing of cutting speed.In the same conditions,the cutting force could be reduced by using straight blade cutting tool and ramp cutting way.Through the multifactor interaction impact test of the cutting way,the blade type and the cutting speed,it was found that the corresponding F-value of the three factors were 21.316,49.141 and 0.222,which suggests that the blade type is the most significant factor for the cutting force.展开更多
BACKGROUND Candy cane syndrome(CCS)is a condition that occurs following gastrectomy or gastric bypass.CCS remains underrecognized,yet its prevalence is likely to rise due to the obesity epidemic and increased use of b...BACKGROUND Candy cane syndrome(CCS)is a condition that occurs following gastrectomy or gastric bypass.CCS remains underrecognized,yet its prevalence is likely to rise due to the obesity epidemic and increased use of bariatric surgery.No previous literature review on this subject has been published.AIM To collate the current knowledge on CCS.METHODS A literature search was conducted with PubMed and Google Scholar for studies from May 2007,until March 2023.The bibliographies of the retrieved articles were manually searched for additional relevant articles.RESULTS Twenty-one articles were identified(135 patients).Abdominal pain,nausea/vomiting,and reflux were the most reported symptoms.Upper gastrointestinal(GI)series and endoscopy were performed for diagnosis.Surgical resection of the blind limb was performed in 13 studies with resolution of symptoms in 73%-100%.In surgical series,9 complications were reported with no mortality.One study reported the surgical construction of a jejunal pouch with clinical success.Six studies described endoscopic approaches with 100%clinical success and no complications.In one case report,endoscopic dilation did not improve the patient’s symptoms.CONCLUSION CCS remains underrecognized due to lack of knowledge about this condition.The growth of the obesity epidemic worldwide and the increase in bariatric surgery are likely to increase its prevalence.CCS can be prevented if an elongated blind loop is avoided or if a jejunal pouch is constructed after total gastrectomy.Diagnosis should be based on symptoms,endoscopy,and upper GI series.Blind loop resection is curative but complex and associated with significant complications.Endoscopic management using different approaches to divert flow is effective and should be further explored.展开更多
[Objectives]To explore microRNA expression characteristics related to low temperature stress in chewing cane.[Methods]The research on miRNA under abiotic stress of sugarcane at home and abroad mainly focused on the ty...[Objectives]To explore microRNA expression characteristics related to low temperature stress in chewing cane.[Methods]The research on miRNA under abiotic stress of sugarcane at home and abroad mainly focused on the types and regulation of miRNA under cold,heat,drought,high salt,and mechanical stress.However,there are few studies on miRNA under low temperature stress in chewing cane.The target genes of miR394 and miR825 in chewing cane were predicted and functionally analyzed by bioinformatics technology.[Results]The results showed that the target genes of miR394 and miR825 were mainly members of the WRKY transcription factor family,involved in plant growth,development and stress resistance.Real-time fluorescence quantitative PCR analyzed the expression characteristics of target miRNA in different tissues of chewing cane at different periods of low temperature stress.[Conclusions]The results showed that the expression of chewing cane miR394 and miR408 had temporal and spatial specificity and tissue specificity,both of which could respond to low temperature stress with significant differential expression.展开更多
Coenzyme Q10 (CoQ10), an important antioxidant molecule playing a major role in electron transport chain, has been commercially produced by fermentation process for the use in oral nutraceutical formulations. Construc...Coenzyme Q10 (CoQ10), an important antioxidant molecule playing a major role in electron transport chain, has been commercially produced by fermentation process for the use in oral nutraceutical formulations. Constructing the high-yielding CoQ10 producing strains is a pre-requisite for cost-effective production. A superior mutant strain P-87 generated from Paracoccus denitrificans ATCC 19367, which showed 1.25-fold improvement in specific CoQ10 content higher than the wild type strain at shake flask level, was selected to carry out the studies on CoQ10 yield improvement through fermenter process optimization. In the course of study, initially the cane-molasses-based medium and fed-batch fermentation strategy using pHBA in combination with sucrose were standardized in shake flask using wild type strain. This strategy was subsequently translated at 2 L laboratory fermenter while optimizing the fermentation process parameters using improved mutant strain P-87. Under optimized fermentation condition, mutant strain P-87 produced 49.85 mg/L of CoQ10 having specific content of 1.63 mg/g of DCW, which was 1.36 folds higher than the specific CoQ10 content of wild-type strain under similar optimized condition. The temperature and DO were found to be critical parameters for CoQ10 production by mutant strain P-87. The optimum temperature was found to be 32°C and the optimum DO concentration to be maintained throughout the fermentation cycle was found to be 30% of air saturation. Overall, a new cost-effective process has been established for the production of CoQ10 using the cheaper substrate “cane molasses” and higher CoQ10 producing mutant strain P-87.展开更多
Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this s...Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this study, optimization of biosurfactant production by <i>Pseudomonas aeruginosa</i> strain CGA1 was carried out using response surface methodology. The conventional “One factor at a time” method of optimization was initially adopted to ascertain the impact of different renewable wastes on biosurfactant production. Four independent variables were tested: carbon and nitrogen concentration, medium volume, and inoculum size. Biosurfactant production was based on the emulsification index measurement. Results indicated that the preferred carbon source by the isolate was sugar cane molasses. A 2.31-fold increase in biosurfactant yield and emulsification index of 96.3% ± 0.75% under optimized cultural conditions of 20 g/L of molasses, 5 g/L of sodium nitrate, 1.93 ml inoculum size and 60 ml medium volume in 250 ml conical flask were obtained. The regression coefficient (R<sup>2</sup>) value of 84.15% implied adequate fitness of the model. The surface tension of distilled water was reduced from 72.1 mN/m to 35.0 ± 0.0 mN/m, and critical micelle concentration was attained at 60 mg·L<sup>-1</sup>. FTIR and GC-MS analysis indicated that the biosurfactant was a lipopeptide having characteristic lipid and peptide peak values. This study proves that the sole use of agro-industrial wastes for the production of biosurfactant is very efficient, and ensures the economic feasibility of biosurfactant production.展开更多
According to meteorological conditions for sugar cane growth and development,surface meteorological observation data of Longzhou County in 1981-2010 were taken as basis,to analyze influence of local temperature,precip...According to meteorological conditions for sugar cane growth and development,surface meteorological observation data of Longzhou County in 1981-2010 were taken as basis,to analyze influence of local temperature,precipitation and sunshine conditions on sugar cane planting.Results show that unique climate of Longzhou County is extremely suitable for sugar cane planting and growth.展开更多
Lactic acid bacteria (LAB) were isolated from fresh sugar cane juice. It was found that several isolates exhibited a clear zone and growth on deMan, Rogosa, Sharpe (MRS) agar supplemented with sodium azide, bromocreso...Lactic acid bacteria (LAB) were isolated from fresh sugar cane juice. It was found that several isolates exhibited a clear zone and growth on deMan, Rogosa, Sharpe (MRS) agar supplemented with sodium azide, bromocresol purple and sucrose. However, only 17 isolates which formed large yellow areas were selected for further investigations. These isolates were further identified according to their morphological and biochemical characteristics. It was found that 10 of these isolates were homofermenters. One of these 10 isolates was selected for mutagenesis using chemical (Ethidium bromide) and physical (UV-B) mutagens followed by biochemical characterisation. A total of 112 mutants were isolated and 9 homofermentative isolates were further investigated for their ability to produce lactic acid. 1H-NMR spectroscopy confirmed that all mutant isolates produced lactic acid as the sole fermentation product.展开更多
[ Objective] The paper was to establish a quick detection method for residue of organphosphoras pesticides in chewing cane juices and provide guarantee for edible safety of chewing juice. [ Method] By using QuEChERS a...[ Objective] The paper was to establish a quick detection method for residue of organphosphoras pesticides in chewing cane juices and provide guarantee for edible safety of chewing juice. [ Method] By using QuEChERS and GC-NPD method, a rapid analysis method for residue of six kinds of organphosphorus pesti- cides （dichlorves, chlorpyrifos-methyl, malathion, fenthion, chlorpyrifos and triazophes） in sugarcane juices was established. [ Resdt] QuEChERS method was significantly superior to traditional extraction method and could extract six kinds of organphesphorus pesticides from chewing cane juices effectively, which gready saved organic reagent and time. Good linearity was found in different standard curves; when the concentration of pesticides was from 0. 020 toO. 100 rag/L, the re- covery rate was from 68.58% to 92.85%, and relative standard deviation （RSD） was ranged from 2.16% to 9.89%. [ Conclusion] The sensitivity, accuracy and precision of QuEChERS method were consistent with the technical requirements of pesticide residue determination. It not only could shorten sample processing cycle effectively, but also ensure that no impurity was in the sample peak and the recovery rate was also consistent with the requirements of residual analysis.展开更多
文摘To study the relations of certain morphological and sugar quality characters with sugarcane yield, an experiment was conducted at Wonji and Metehara Sugar Estates, Ethiopia between March 2012 and October 2013. The experiment, comprising of 400 sugarcane genotypes of which 174 were local that were collected from different regional states of Ethiopia and 226 introduced, was laid out in partial balanced lattice design with two replications. Data was collected on cane yield and its components, sugar yield and sugar quality traits. ANOVA, correlation and path coefficient analysis were done. Analysis of variance revealed significant differences (P < 0.01) for all the characters studied. Cane yield showed strong positive and highly significant (P < 0.01) correlation with millable cane number (r = 0.832), single cane weight (r = 0.528), stalk height (r = 0.517) and sugar yield (r = 0.987). There was also positive significant (P = 0.05) correlation of tiller count and cane diameter with cane yield. Path analysis revealed the highest positive direct effect of millable cane number (0.812) on cane yield followed by single cane weight (0.682) and pol percent (0.550). However, stalk diameter and brix percent had considerable negative direct effects and indirect positive effects through single cane weight on cane yield. Therefore, in view of their significant positive association with cane yield, indirect effects of stalk diameter and brix percent via single cane weight should be considered during selection. Genotypes should be selected on the basis of millable cane number, single cane weight and pol percent for getting higher cane and sugar yield.
文摘The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings.
基金supported by the National Key Research and Development Program of China(2016YFD0500505)the National Nature Science Foundation of China (No.31272485)
文摘The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract(SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs.Eighteen barrows(Duroc × Landrace × Jiaxing Black), with an average initial body weight of 62.1 ± 5.0 kg,were randomly allotted to 1 of 3 diets with 6 replicates per treatment for 42 days. The diets comprised a normal diet and the normal diets supplemented with 5 and 25 g/kg SCE. The results showed that SCE supplementation did not affect final body weight of finishing pigs. Dietary SCE supplementation significantly increased(P < 0.05) Longissimus dorsi muscle pH_(24 h),and tended to reduce(P < 0.1) and significantly decreased(P < 0.05) shear force, drip loss, myofiber cross sectional area and lactate dehydrogenase activity at 5 and 25 g/kg, respectively. Meanwhile, dietary SCE treatments significantly decreased(P < 0.05) malonaldehyde content and total superoxide dismutase activity in Longissimus dorsi muscle, and tended to reduce(P < 0.1) malonaldehyde content in serum. Altogether, these data indicate that SCE is an effective feed additive to improve pork meat quality, and the underlying mechanism may be partly due to the improved oxidative stability induced by dietary SCE supplementation.
基金National Natural Science Foundation of China(31401290)Guangxi Natural Science Foundation(2015GXNSFBA139261)Guangxi Experiment Center of Science&Technology(YXKT2014003)
文摘In order to investigate the visible-NIR spectral features of the leaves of a sugarcane variety(ROC 22),the spectral reflectance and the chlorophyll content were measured in the laboratory,and their correlations were analyzed.Prediction models were built eventually.Results showed that the negative correlations with r greater than 0.8 was found in 527-578 nm and 701-731nm between spectral reflectance and chlorophyll content.And the red edge position(REP)was also found having high correlation with chlorophyll content,with the highest r of 0.8442.In order to explore the most sensitive bands for normalized difference vegetation index(NDVI),48471 NDVI values were computed with different wavebands for each sample and their correlations with chlorophyll were also analyzed.The distribution maps of NDVI and its correlations in a two-spectral-dimension space both indicated that the red bands had significant influence than the NIR bands.The suggested sensitive red range was 710-735 nm,especially720-725 nm;and the sensitive NIR range was from 780-850 nm,which had the higher robustness.The chlorophyll predication model with NDVI(725 and 840 nm)in tillering stage had determination coefficients of 0.7386,and was recommended for guiding the subsequent ridging fertilization.
基金the National Key Technologies R&D Program of China(No.2014BAD08B04)the National Natural Science Fund of China(No.51175230,No.51475212)+1 种基金Independent Innovation of Agricultural Science and Technology Project in Jiangsu Province(cx(10)224)Research and Innovation Project for College Graduates of Jiangsu Province of China(CXLX12_0625).
文摘To obtain the mechanical properties of greenhouse cucumber cane,tensile and shear properties of the greenhouse cucumber cane were studied by using computer-controlled electronic universal testing machine and homemade cutting test bench,respectively.Firstly,the root,middle and head of cucumber cane were subjected for tensile tests.The tensile stress-strain curves showed that the root of cumber cane presented the characteristics of plastic material,while the middle and head showed the characteristics of brittle material.The average tensile strength of root,middle and head of fresh cucumber cane were 7.35 MPa,6.30 MPa and 4.68 MPa,respectively.The average elastic modulus of root of fresh cucumber cane was 280.58 MPa,which was much greater than the middle and head with average elastic modulus of 198.81 MPa and 137.22 MPa,respectively.A pendulum impact cutting test-rig and a cutting force measurement system composed of a cantilever weigh sensor,a high frequency DAQ card and motion control card were developed.The cutting mechanical property experiments of different parts of greenhouse cucumber cane were carried out,and the continuous curves of cutting force were measured.The single factor test for cross-sectional area,cutting speed,cutting tool type and manner were analyzed.The results indicated that the peak cutting force increased approximately linearly with the increasing of cutting sectional area,but decreased gradually with the increasing of cutting speed.In the same conditions,the cutting force could be reduced by using straight blade cutting tool and ramp cutting way.Through the multifactor interaction impact test of the cutting way,the blade type and the cutting speed,it was found that the corresponding F-value of the three factors were 21.316,49.141 and 0.222,which suggests that the blade type is the most significant factor for the cutting force.
文摘BACKGROUND Candy cane syndrome(CCS)is a condition that occurs following gastrectomy or gastric bypass.CCS remains underrecognized,yet its prevalence is likely to rise due to the obesity epidemic and increased use of bariatric surgery.No previous literature review on this subject has been published.AIM To collate the current knowledge on CCS.METHODS A literature search was conducted with PubMed and Google Scholar for studies from May 2007,until March 2023.The bibliographies of the retrieved articles were manually searched for additional relevant articles.RESULTS Twenty-one articles were identified(135 patients).Abdominal pain,nausea/vomiting,and reflux were the most reported symptoms.Upper gastrointestinal(GI)series and endoscopy were performed for diagnosis.Surgical resection of the blind limb was performed in 13 studies with resolution of symptoms in 73%-100%.In surgical series,9 complications were reported with no mortality.One study reported the surgical construction of a jejunal pouch with clinical success.Six studies described endoscopic approaches with 100%clinical success and no complications.In one case report,endoscopic dilation did not improve the patient’s symptoms.CONCLUSION CCS remains underrecognized due to lack of knowledge about this condition.The growth of the obesity epidemic worldwide and the increase in bariatric surgery are likely to increase its prevalence.CCS can be prevented if an elongated blind loop is avoided or if a jejunal pouch is constructed after total gastrectomy.Diagnosis should be based on symptoms,endoscopy,and upper GI series.Blind loop resection is curative but complex and associated with significant complications.Endoscopic management using different approaches to divert flow is effective and should be further explored.
基金Supported by Science and Technology Research Project of Henan Provincial Science and Technology Department(222102110448)Key Scientific Research Projects of Colleges and Universities in Henan Province(21B210007)Open Research Project of Guangxi Sugarcane Genetic Improvement Key Laboratory(19-185-24-K-01-01).
文摘[Objectives]To explore microRNA expression characteristics related to low temperature stress in chewing cane.[Methods]The research on miRNA under abiotic stress of sugarcane at home and abroad mainly focused on the types and regulation of miRNA under cold,heat,drought,high salt,and mechanical stress.However,there are few studies on miRNA under low temperature stress in chewing cane.The target genes of miR394 and miR825 in chewing cane were predicted and functionally analyzed by bioinformatics technology.[Results]The results showed that the target genes of miR394 and miR825 were mainly members of the WRKY transcription factor family,involved in plant growth,development and stress resistance.Real-time fluorescence quantitative PCR analyzed the expression characteristics of target miRNA in different tissues of chewing cane at different periods of low temperature stress.[Conclusions]The results showed that the expression of chewing cane miR394 and miR408 had temporal and spatial specificity and tissue specificity,both of which could respond to low temperature stress with significant differential expression.
文摘Coenzyme Q10 (CoQ10), an important antioxidant molecule playing a major role in electron transport chain, has been commercially produced by fermentation process for the use in oral nutraceutical formulations. Constructing the high-yielding CoQ10 producing strains is a pre-requisite for cost-effective production. A superior mutant strain P-87 generated from Paracoccus denitrificans ATCC 19367, which showed 1.25-fold improvement in specific CoQ10 content higher than the wild type strain at shake flask level, was selected to carry out the studies on CoQ10 yield improvement through fermenter process optimization. In the course of study, initially the cane-molasses-based medium and fed-batch fermentation strategy using pHBA in combination with sucrose were standardized in shake flask using wild type strain. This strategy was subsequently translated at 2 L laboratory fermenter while optimizing the fermentation process parameters using improved mutant strain P-87. Under optimized fermentation condition, mutant strain P-87 produced 49.85 mg/L of CoQ10 having specific content of 1.63 mg/g of DCW, which was 1.36 folds higher than the specific CoQ10 content of wild-type strain under similar optimized condition. The temperature and DO were found to be critical parameters for CoQ10 production by mutant strain P-87. The optimum temperature was found to be 32°C and the optimum DO concentration to be maintained throughout the fermentation cycle was found to be 30% of air saturation. Overall, a new cost-effective process has been established for the production of CoQ10 using the cheaper substrate “cane molasses” and higher CoQ10 producing mutant strain P-87.
文摘Biosurfactants are biomolecules produced by microorganisms, which possess several advantages over their chemical counterparts. Production can be cost-effective if renewable wastes are utilized as substrates. In this study, optimization of biosurfactant production by <i>Pseudomonas aeruginosa</i> strain CGA1 was carried out using response surface methodology. The conventional “One factor at a time” method of optimization was initially adopted to ascertain the impact of different renewable wastes on biosurfactant production. Four independent variables were tested: carbon and nitrogen concentration, medium volume, and inoculum size. Biosurfactant production was based on the emulsification index measurement. Results indicated that the preferred carbon source by the isolate was sugar cane molasses. A 2.31-fold increase in biosurfactant yield and emulsification index of 96.3% ± 0.75% under optimized cultural conditions of 20 g/L of molasses, 5 g/L of sodium nitrate, 1.93 ml inoculum size and 60 ml medium volume in 250 ml conical flask were obtained. The regression coefficient (R<sup>2</sup>) value of 84.15% implied adequate fitness of the model. The surface tension of distilled water was reduced from 72.1 mN/m to 35.0 ± 0.0 mN/m, and critical micelle concentration was attained at 60 mg·L<sup>-1</sup>. FTIR and GC-MS analysis indicated that the biosurfactant was a lipopeptide having characteristic lipid and peptide peak values. This study proves that the sole use of agro-industrial wastes for the production of biosurfactant is very efficient, and ensures the economic feasibility of biosurfactant production.
文摘According to meteorological conditions for sugar cane growth and development,surface meteorological observation data of Longzhou County in 1981-2010 were taken as basis,to analyze influence of local temperature,precipitation and sunshine conditions on sugar cane planting.Results show that unique climate of Longzhou County is extremely suitable for sugar cane planting and growth.
文摘Lactic acid bacteria (LAB) were isolated from fresh sugar cane juice. It was found that several isolates exhibited a clear zone and growth on deMan, Rogosa, Sharpe (MRS) agar supplemented with sodium azide, bromocresol purple and sucrose. However, only 17 isolates which formed large yellow areas were selected for further investigations. These isolates were further identified according to their morphological and biochemical characteristics. It was found that 10 of these isolates were homofermenters. One of these 10 isolates was selected for mutagenesis using chemical (Ethidium bromide) and physical (UV-B) mutagens followed by biochemical characterisation. A total of 112 mutants were isolated and 9 homofermentative isolates were further investigated for their ability to produce lactic acid. 1H-NMR spectroscopy confirmed that all mutant isolates produced lactic acid as the sole fermentation product.
基金Supported by Basic Scientific Research Special Project of Guangxi Academy of Agricultural Sciences(GNK2012YM11)Scientific Research and Technology Development Program of Nanning City(201102026B)+1 种基金Fundamental Research Project of Guangxi Academy of Agricultural Sciences(G2009001,201001G)Science and Technology Development Fund Project of Guangxi Academy of Agricultural Sciences(201002Z)
文摘[ Objective] The paper was to establish a quick detection method for residue of organphosphoras pesticides in chewing cane juices and provide guarantee for edible safety of chewing juice. [ Method] By using QuEChERS and GC-NPD method, a rapid analysis method for residue of six kinds of organphosphorus pesti- cides （dichlorves, chlorpyrifos-methyl, malathion, fenthion, chlorpyrifos and triazophes） in sugarcane juices was established. [ Resdt] QuEChERS method was significantly superior to traditional extraction method and could extract six kinds of organphesphorus pesticides from chewing cane juices effectively, which gready saved organic reagent and time. Good linearity was found in different standard curves; when the concentration of pesticides was from 0. 020 toO. 100 rag/L, the re- covery rate was from 68.58% to 92.85%, and relative standard deviation （RSD） was ranged from 2.16% to 9.89%. [ Conclusion] The sensitivity, accuracy and precision of QuEChERS method were consistent with the technical requirements of pesticide residue determination. It not only could shorten sample processing cycle effectively, but also ensure that no impurity was in the sample peak and the recovery rate was also consistent with the requirements of residual analysis.
