Novel substrates consisted of different fresh agro-industrial residues,their corresponding and commercial spent mushroom substrates(i.e.SMS deriving from laboratory-scale experiments and SMS deriving from industrial-s...Novel substrates consisted of different fresh agro-industrial residues,their corresponding and commercial spent mushroom substrates(i.e.SMS deriving from laboratory-scale experiments and SMS deriving from industrial-scale experiments by Green Zin S.A.-SMS GZ)and Pleurotus waste(PW;stipes/mishappen mushrooms)were used in blends for a new cultivation cycle of Pleurotus ostreatus and P.eryngii mushrooms in bags.Their impact on the biochemical properties(intra-cellular polysaccharides-IPSs,protein,lipid,total phenolic compounds-TPCs,individual carbohydrates composition of the IPSs)in the first-and second-flush whole mushrooms,pilei and stipes,as well as the fatty acids composition,the antioxidant activity(in the first-flush mushroom parts)and glucan content of stipes were examined.Both species produced satisfactory IPSs quantities in all substrates(28.69-46.38%,w/w)and significant protein amounts(18.37-26.80%,w/w).The further SMS addition(80%,w/w instead of 40%,w/w)in the cultivation substrates affected positively the mushroom IPSs values,whereas the highest protein content was detected in mushroom’s parts cultivated on substrates consisted of fresh agro-industrial residues.Mushroom’s lipid content was affected differently by the various substrate combinations,with SMS presence resulting in mushrooms with a lower fat content than those produced in substrates with PW addition.Fresh substrates with PW and those with coffee residue were the most favorable for TPCs production.Regarding production flushes,the nutritional value of mushrooms was comparable between them,only a slight increase in TPCs of second-flush carposomes was detected.Glucose was the predominant monosaccharide of the produced IPSs,combined with a significant production of total and β-glucans.SMSs and PW addition had a positive impact on antioxidant activity,too.A higher quantity of lipids,TPCs and significant antioxidant activity were detected in all Pleurotus pilei than stipes,whereas the latter were richer in IPSs.Both pilei and stipes had a significant protein amount.Hence,the data obtained by this study support the positive effect of different types of SMS and mushroom waste on P.ostreatus and P.eryngii nutritional value.展开更多
Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and c...Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy planning.The use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality traits.Many studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing data.In this paper,the key quality traits that are of interest to producers and consumers are introduced.The literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality prediction.This review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.展开更多
Mushroom cultivation is an implementation of the industrial biotechnology in the valorization of various lignocellulosic materials.In the present study,common lignocellulosic residues(wheat straw-WS and barley and oat...Mushroom cultivation is an implementation of the industrial biotechnology in the valorization of various lignocellulosic materials.In the present study,common lignocellulosic residues(wheat straw-WS and barley and oats straw-BOS)were supplemented with‘novel’compounds(sunflower and corn oil,yeast extract and CaSO4⋅2H2O)and their impact on the biochemical properties(composition of intra-cellular polysaccharides-IPSs,proteins,lipids,glucans,tocopherol content,carbohydrates and fatty acids composition),total phenolic compounds(TPCs)and the antioxidant activity of Pleurotus ostreatus and Pleurotus eryngii mushrooms,cultivated in‘bag-logs’,was evaluated.Results revealed that supplements enhanced IPSs in carposomes cultivated on BOS substrates and the most positive were corn oil 2%,w/w and CaSO4⋅2H2O for P.ostreatus and P.eryngii,respectively(50.86 and 57.65%,w/w).In all treatments,there was a variety in the carbohydrate’s composition and a great production of glucans(40.67-62.15%,w/w),especially of the bioactiveβ-glucans(32.10-61.93%,w/w)in the stipes of both species.Significant protein content was detected in P.ostreatus and P.eryngii carposomes grown on substrates with yeast extract(28.99 and 30.09%,w/w;WS and 29.49 and 24.94%,w/w;BOS).Although mushrooms presented a low lipid content in general,high values of fat content were observed for both species when cultivated on BOS substrate supplemented with sunflower and corn oil(4.54-6.58%,w/w).The nutritional value of mushrooms was comparable between the two flushes.The greatest amount of TPCs were detected in supplemented WS(22.31-35.30 mg gallic acid equivalents/g d.w.)and BOS(21.03-41.74 mg gallic acid equivalents/g d.w.)with CaSO4⋅2H2O,in all parts of mushrooms and a strong antioxidant activity and tocopherols production,in all treatments.A higher quantity of lipids,antioxidant activity and reducing power was present in the pilei rather than the stipes,while the latter were richer in IPSs,regardless of the supplement’s presence.Therefore,the outlined supplemented substrates could be used to produce mushrooms with high nutritional and medicinal values.展开更多
During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle e...During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle exit. The aim of this study was to contribute to the comprehension of spray formation. Surfactant influence on spray characteristics was studied by comparing water spray with sprays containing three different surfactants, Two nozzles including a classical hollow cone nozzle ATR （Albuz, France） and an air-induced hollow cone nozzle TVI which is a low-drift nozzle （Albuz, France） were chosen. Radial profiles of the axial velocity component and Sauter mean diameter at two axial distances from the nozzle exit were measured using a Phase Doppler Particle Analyzer （PDPA）. Results showed that sprays issued from ATR and TVI nozzles were very different, even when water was sprayed. Effect of adding surfactant depended on the nozzle type. Sheet thickness was reduced by adding Elton and Heliosol regardless of the nozzle type. They reduced spray angle of ATR nozzle spray but did not affect that of YVI nozzle. Break-Thru has a slight effect when sprayed through the ATR nozzle, but it has the most pronounced effect on the SMD when sprayed through the TVI nozzle.展开更多
Objective: To evaluate the antidiabetic effect of galactomannans extracted from Adenanthera pavonina's L.seeds(GAP) in streptozotocin(STZ) induced diabetic mice.Methods:The preliminary galactomannan yield from Ade...Objective: To evaluate the antidiabetic effect of galactomannans extracted from Adenanthera pavonina's L.seeds(GAP) in streptozotocin(STZ) induced diabetic mice.Methods:The preliminary galactomannan yield from Adenanthera pavonina L.plant and extraction products composition were evaluated.Various chemical characterization methods like thin layer chromatography, Fourier transform infrared spectroscopy, ~1H and ^(13)C nuclear magnetic resonance, and molecular weight by gel permeation chromatography have been employed to characterize the extracted galactomannan.The mice were divided in four groups: Normal control, diabetic control, GAP(1% and 2%) treated and standard drug treated groups.Diabetic mice received treatment daily for 30 d.Diabetes was induced by STZ at a single dose of 120 mg/kg.Body weight, water and food intake, fasting blood glucose, total cholesterol and triglycerides were measured.Histopathological analysis of pancreas and liver were performed to evaluate STZ-induced tissue injuries.Results: The isolated and extracted galactomannan from Adenanthera pavonina was confirmed by various chemical characterization methods.GAP exhibited a 1.46:1 mannose: galactose ratio, and high molar weight.Both GAP enriched food decreased glycaemia, total cholesterol and triacylglycerol.GAP didn't interfere on food intakes or body weight, although it increased water intake.Furthermore, the relative liver weight indicated toxic galactomannan effects on the histopathological changes of the pancreas in STZ induced diabetes.Conclusions: It is concluded that GAP is a natural product that contains potent galactomannan and is useful in preventing and treating diabetes.展开更多
Five agro-industrial residues,their corresponding spent mushroom substrates(SMS),commercial fresh and spent mushroom compost of Agaricus(SMC)and Pleurotus ostreatus(SMS GZ)cultivation,Pleurotus and Agaricus waste(stip...Five agro-industrial residues,their corresponding spent mushroom substrates(SMS),commercial fresh and spent mushroom compost of Agaricus(SMC)and Pleurotus ostreatus(SMS GZ)cultivation,Pleurotus and Agaricus waste(stipes/mishappen mushrooms)were combined and re-utilized as novel substrates for the cultivation of P.ostreatus,P.eryngii and A.bisporus mushrooms.SMSs/SMC were used up to 40%(treatment 1 and 2),while 20%of mushroom waste were added in fresh and spent substrates(treatment 3 and 4).The impact of different substrates on mycelial growth rate and biomass production was examined.Then,Pleurotus spp.were cultivated on the most promising substrates and essential cultivation aspects(earliness,total mushroom yield,biological efficiency-BE)and carposomes’quality parameters(weight,morphological characteristics)were evaluated.Laccase and endoglucanase production by Pleurotus species were also determined at 50 and 100%of colonization stages.All species showed their fastest mycelial growth rate(up to 5 mm/day)on substrates consisted of SMC,whereas many combinations of species/substrate enhanced biomass production.The SMS GZ supplementation positively affected laccase activity;in the cultures of P.ostreatus and P.eryngii the highest values were 62,539 and 17,584 U/g d.w.,respectively.On the contrary,small amounts of endoglucanase were produced(0.007 to 0.322 U/g d.w.);the greatest production was recorded for P.ostreatus at full colonization.Regarding fermentation in bags,significant amount of total mushroom yield was produced in all substrates and those with SMS GZ supported the fastest earliness period and the highest BE for both Pleurotus species.BE values ranged from 54 to 133%for P.ostreatus and from 53 to 121%for P.eryngii.Concerning morphological characteristics,mushroom waste addition seemed to affect them positively.The data included in this paper support the effective re-utilization of different types of SMS and mushroom waste for fungal mass and enzymes’production and for new high quality Pleurotus spp.carposomes.展开更多
The suitability of the abundant agro-industrial residues wheat straw(WS;control),barley and oats straw(BOS)and rice husk(RH),supplemented with various sources of oils(sunflower,corn oil),nitrogen(peptone,yeast extract...The suitability of the abundant agro-industrial residues wheat straw(WS;control),barley and oats straw(BOS)and rice husk(RH),supplemented with various sources of oils(sunflower,corn oil),nitrogen(peptone,yeast extract)and calcium salts(CaSO_(4)⋅2H_(2)O,CaCl2),as novel substrates in solid-state fermentation of selected Pleurotus ostreatus and P.eryngii mushrooms was investigated.The possible effect of different additives on mycelial growth rate,biomass production and endoglucanase,laccase and lipase biosynthesis were evaluated.Moreover,their impact on essential cultivation aspects(earliness,total mushroom yield,biological efficiency)and carposome quality parameters(weight,morphological characteristics)was assessed.Both fungi showed their highest growth rates on BOS substrates and the most positive implementation was CaSO_(4)⋅2H_(2)O 6%w/w(Kr=9.58 mm/day;P.ostreatus,Kr=9.42 mm/day;P.eryngii),while different additives led to enhancement of biomass production.Pleurotus species demonstrated minimal levels of endoglucanase activity,with values ranging from 0.01 to 0.42 U/g of dry weight,regardless of the substrate and the stage of colonization.On the contrary,the maximum values of laccase activity were observed at 50%of colonization on BOS and RH,while supplementation with nitrogen and calcium sources positively affected its biosynthesis.P.ostreatus and P.eryngii cultivated on BOS supplemented with peptone at 2 and 5%w/w,synthesized significant laccase amounts,i.e.,12,165.78 and 8,624.55 U/g d.w.,respectively.Satisfactory amounts of lipase were produced,especially in substrates supplemented with sunflower 2%w/w,in quantities up to 1.42 U/g d.w.,whereas the highest lipase activity was achieved by P.eryngii on WS supplemented with corn oil at 2%w/w,with a value of 4.25 U/g d.w.being recorded.Regarding fermentation of Pleurotus species in polypropylene bags,WS and BOS supported faster colonization and shorter earliness period than RH substrates,whereas supplementation did not seem to affect these culture parameters.Furthermore,oils supplementation had a positive effect on BE of both species,with values up to 100%for P.ostreatus and 80%for P.eryngii on WS and BOS,whereas on RH the lowest BE values were detected.Morphological characteristics were not significantly affected by the additives.Results indicate the positive impact that certain additives have on mushroom productivity and production of enzymes with great financial and environmental importance.展开更多
This paper considers the production of biomass of two interconnected chemostats in series with biomass mortality and a growth kinetic of the biomass described by an increasing function.A comparison is made with the pr...This paper considers the production of biomass of two interconnected chemostats in series with biomass mortality and a growth kinetic of the biomass described by an increasing function.A comparison is made with the productivity of a single chemostat with the same mortality rate and with volume equal to the sum of the volumes of the two chemostats.We determine the operating conditions under which the productivity of the serial configuration is greater than the productivity of the single chemostat.Moreover,the differences and similarities in the results corresponding to the case with mortality and the one without mortality,are highlighted.The mortality leads to surprising results where the productivity of a steady state where the bacteria are washed out in the first chemostat is greater than the one where the bacteria are present in both chemostats.展开更多
The objective of this study is to analyze a model of competition for one resource in the chemostat with general interspecific density-dependent growth rates,taking into account the predator–prey relationship.This rel...The objective of this study is to analyze a model of competition for one resource in the chemostat with general interspecific density-dependent growth rates,taking into account the predator–prey relationship.This relationship is characterized by the fact that the prey species promotes the growth of the predator species which in turn inhibits the growth of the first species.The model is a three-dimensional system of ordinary differential equations.With the same dilution rates,the model can be reduced to a planar system where the two models have the same local and even global behavior.The existence and stability conditions of all steady states of the reduced model in the plane are determined according to the operating parameters.Using the nullcline method,we present a geometric characterization of the existence and stability of all equilibria showing the multiplicity of coexistence steady states.The bifurcation diagrams illustrate that the steady states can appear or disappear only through saddle-node or transcritical bifurcations.Moreover,the operating diagrams describe the asymptotic behavior of this system by varying the control parameters and show the effect of the inhibition of predation on the emergence of the bistability region and the reduction until the disappearance of the coexistence region by increasing this inhibition parameter.展开更多
文摘Novel substrates consisted of different fresh agro-industrial residues,their corresponding and commercial spent mushroom substrates(i.e.SMS deriving from laboratory-scale experiments and SMS deriving from industrial-scale experiments by Green Zin S.A.-SMS GZ)and Pleurotus waste(PW;stipes/mishappen mushrooms)were used in blends for a new cultivation cycle of Pleurotus ostreatus and P.eryngii mushrooms in bags.Their impact on the biochemical properties(intra-cellular polysaccharides-IPSs,protein,lipid,total phenolic compounds-TPCs,individual carbohydrates composition of the IPSs)in the first-and second-flush whole mushrooms,pilei and stipes,as well as the fatty acids composition,the antioxidant activity(in the first-flush mushroom parts)and glucan content of stipes were examined.Both species produced satisfactory IPSs quantities in all substrates(28.69-46.38%,w/w)and significant protein amounts(18.37-26.80%,w/w).The further SMS addition(80%,w/w instead of 40%,w/w)in the cultivation substrates affected positively the mushroom IPSs values,whereas the highest protein content was detected in mushroom’s parts cultivated on substrates consisted of fresh agro-industrial residues.Mushroom’s lipid content was affected differently by the various substrate combinations,with SMS presence resulting in mushrooms with a lower fat content than those produced in substrates with PW addition.Fresh substrates with PW and those with coffee residue were the most favorable for TPCs production.Regarding production flushes,the nutritional value of mushrooms was comparable between them,only a slight increase in TPCs of second-flush carposomes was detected.Glucose was the predominant monosaccharide of the produced IPSs,combined with a significant production of total and β-glucans.SMSs and PW addition had a positive impact on antioxidant activity,too.A higher quantity of lipids,TPCs and significant antioxidant activity were detected in all Pleurotus pilei than stipes,whereas the latter were richer in IPSs.Both pilei and stipes had a significant protein amount.Hence,the data obtained by this study support the positive effect of different types of SMS and mushroom waste on P.ostreatus and P.eryngii nutritional value.
基金This study was supported by the National Natural Science Foundation of China(42271396)the Natural Science Foundation of Shandong Province(ZR2022MD017)+1 种基金the Key R&D Project of Hebei Province(22326406D)The European Space Agency(ESA)and Ministry of Science and Technology of China(MOST)Dragon(57457).
文摘Cereal is an essential source of calories and protein for the global population.Accurately predicting cereal quality before harvest is highly desirable in order to optimise management for farmers,grading harvest and categorised storage for enterprises,future trading prices,and policy planning.The use of remote sensing data with extensive spatial coverage demonstrates some potential in predicting crop quality traits.Many studies have also proposed models and methods for predicting such traits based on multiplatform remote sensing data.In this paper,the key quality traits that are of interest to producers and consumers are introduced.The literature related to grain quality prediction was analyzed in detail,and a review was conducted on remote sensing platforms,commonly used methods,potential gaps,and future trends in crop quality prediction.This review recommends new research directions that go beyond the traditional methods and discusses grain quality retrieval and the associated challenges from the perspective of remote sensing data.
基金co-financed by the European Regional Development Fund of the European Union and Greek national funds(European Social Fund-ESF)through the Operational Program Competitiveness,Entrepreneurship and Innovation,under the call RESEARCH-CREATE-INNOVATE(project code:Τ1EDK-05027)scien-tifically coordinated by the Hellenic Agricultural Organization-Dimitra(Institute of Technology of Agricultural Products/Laboratory of Edible Fungi).
文摘Mushroom cultivation is an implementation of the industrial biotechnology in the valorization of various lignocellulosic materials.In the present study,common lignocellulosic residues(wheat straw-WS and barley and oats straw-BOS)were supplemented with‘novel’compounds(sunflower and corn oil,yeast extract and CaSO4⋅2H2O)and their impact on the biochemical properties(composition of intra-cellular polysaccharides-IPSs,proteins,lipids,glucans,tocopherol content,carbohydrates and fatty acids composition),total phenolic compounds(TPCs)and the antioxidant activity of Pleurotus ostreatus and Pleurotus eryngii mushrooms,cultivated in‘bag-logs’,was evaluated.Results revealed that supplements enhanced IPSs in carposomes cultivated on BOS substrates and the most positive were corn oil 2%,w/w and CaSO4⋅2H2O for P.ostreatus and P.eryngii,respectively(50.86 and 57.65%,w/w).In all treatments,there was a variety in the carbohydrate’s composition and a great production of glucans(40.67-62.15%,w/w),especially of the bioactiveβ-glucans(32.10-61.93%,w/w)in the stipes of both species.Significant protein content was detected in P.ostreatus and P.eryngii carposomes grown on substrates with yeast extract(28.99 and 30.09%,w/w;WS and 29.49 and 24.94%,w/w;BOS).Although mushrooms presented a low lipid content in general,high values of fat content were observed for both species when cultivated on BOS substrate supplemented with sunflower and corn oil(4.54-6.58%,w/w).The nutritional value of mushrooms was comparable between the two flushes.The greatest amount of TPCs were detected in supplemented WS(22.31-35.30 mg gallic acid equivalents/g d.w.)and BOS(21.03-41.74 mg gallic acid equivalents/g d.w.)with CaSO4⋅2H2O,in all parts of mushrooms and a strong antioxidant activity and tocopherols production,in all treatments.A higher quantity of lipids,antioxidant activity and reducing power was present in the pilei rather than the stipes,while the latter were richer in IPSs,regardless of the supplement’s presence.Therefore,the outlined supplemented substrates could be used to produce mushrooms with high nutritional and medicinal values.
文摘During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle exit. The aim of this study was to contribute to the comprehension of spray formation. Surfactant influence on spray characteristics was studied by comparing water spray with sprays containing three different surfactants, Two nozzles including a classical hollow cone nozzle ATR （Albuz, France） and an air-induced hollow cone nozzle TVI which is a low-drift nozzle （Albuz, France） were chosen. Radial profiles of the axial velocity component and Sauter mean diameter at two axial distances from the nozzle exit were measured using a Phase Doppler Particle Analyzer （PDPA）. Results showed that sprays issued from ATR and TVI nozzles were very different, even when water was sprayed. Effect of adding surfactant depended on the nozzle type. Sheet thickness was reduced by adding Elton and Heliosol regardless of the nozzle type. They reduced spray angle of ATR nozzle spray but did not affect that of YVI nozzle. Break-Thru has a slight effect when sprayed through the ATR nozzle, but it has the most pronounced effect on the SMD when sprayed through the TVI nozzle.
基金support by Brazilian governmental agency FUNCAP(Ceara State Research Funding)
文摘Objective: To evaluate the antidiabetic effect of galactomannans extracted from Adenanthera pavonina's L.seeds(GAP) in streptozotocin(STZ) induced diabetic mice.Methods:The preliminary galactomannan yield from Adenanthera pavonina L.plant and extraction products composition were evaluated.Various chemical characterization methods like thin layer chromatography, Fourier transform infrared spectroscopy, ~1H and ^(13)C nuclear magnetic resonance, and molecular weight by gel permeation chromatography have been employed to characterize the extracted galactomannan.The mice were divided in four groups: Normal control, diabetic control, GAP(1% and 2%) treated and standard drug treated groups.Diabetic mice received treatment daily for 30 d.Diabetes was induced by STZ at a single dose of 120 mg/kg.Body weight, water and food intake, fasting blood glucose, total cholesterol and triglycerides were measured.Histopathological analysis of pancreas and liver were performed to evaluate STZ-induced tissue injuries.Results: The isolated and extracted galactomannan from Adenanthera pavonina was confirmed by various chemical characterization methods.GAP exhibited a 1.46:1 mannose: galactose ratio, and high molar weight.Both GAP enriched food decreased glycaemia, total cholesterol and triacylglycerol.GAP didn't interfere on food intakes or body weight, although it increased water intake.Furthermore, the relative liver weight indicated toxic galactomannan effects on the histopathological changes of the pancreas in STZ induced diabetes.Conclusions: It is concluded that GAP is a natural product that contains potent galactomannan and is useful in preventing and treating diabetes.
文摘Five agro-industrial residues,their corresponding spent mushroom substrates(SMS),commercial fresh and spent mushroom compost of Agaricus(SMC)and Pleurotus ostreatus(SMS GZ)cultivation,Pleurotus and Agaricus waste(stipes/mishappen mushrooms)were combined and re-utilized as novel substrates for the cultivation of P.ostreatus,P.eryngii and A.bisporus mushrooms.SMSs/SMC were used up to 40%(treatment 1 and 2),while 20%of mushroom waste were added in fresh and spent substrates(treatment 3 and 4).The impact of different substrates on mycelial growth rate and biomass production was examined.Then,Pleurotus spp.were cultivated on the most promising substrates and essential cultivation aspects(earliness,total mushroom yield,biological efficiency-BE)and carposomes’quality parameters(weight,morphological characteristics)were evaluated.Laccase and endoglucanase production by Pleurotus species were also determined at 50 and 100%of colonization stages.All species showed their fastest mycelial growth rate(up to 5 mm/day)on substrates consisted of SMC,whereas many combinations of species/substrate enhanced biomass production.The SMS GZ supplementation positively affected laccase activity;in the cultures of P.ostreatus and P.eryngii the highest values were 62,539 and 17,584 U/g d.w.,respectively.On the contrary,small amounts of endoglucanase were produced(0.007 to 0.322 U/g d.w.);the greatest production was recorded for P.ostreatus at full colonization.Regarding fermentation in bags,significant amount of total mushroom yield was produced in all substrates and those with SMS GZ supported the fastest earliness period and the highest BE for both Pleurotus species.BE values ranged from 54 to 133%for P.ostreatus and from 53 to 121%for P.eryngii.Concerning morphological characteristics,mushroom waste addition seemed to affect them positively.The data included in this paper support the effective re-utilization of different types of SMS and mushroom waste for fungal mass and enzymes’production and for new high quality Pleurotus spp.carposomes.
基金the European Regional Development Fund of the European Union and Greek national funds(European Social Fund-ESF)through the Operational Program Competitiveness,Entrepreneurship and Innovation,under the call RESEARCH-CREATE-INNOVATE(project code:Τ1EDK-05027),scientifically coordinated by the Hellenic Agricultural Organization-Dimitra(Institute of Technology of Agricultural Products/Laboratory of Edible Fungi).
文摘The suitability of the abundant agro-industrial residues wheat straw(WS;control),barley and oats straw(BOS)and rice husk(RH),supplemented with various sources of oils(sunflower,corn oil),nitrogen(peptone,yeast extract)and calcium salts(CaSO_(4)⋅2H_(2)O,CaCl2),as novel substrates in solid-state fermentation of selected Pleurotus ostreatus and P.eryngii mushrooms was investigated.The possible effect of different additives on mycelial growth rate,biomass production and endoglucanase,laccase and lipase biosynthesis were evaluated.Moreover,their impact on essential cultivation aspects(earliness,total mushroom yield,biological efficiency)and carposome quality parameters(weight,morphological characteristics)was assessed.Both fungi showed their highest growth rates on BOS substrates and the most positive implementation was CaSO_(4)⋅2H_(2)O 6%w/w(Kr=9.58 mm/day;P.ostreatus,Kr=9.42 mm/day;P.eryngii),while different additives led to enhancement of biomass production.Pleurotus species demonstrated minimal levels of endoglucanase activity,with values ranging from 0.01 to 0.42 U/g of dry weight,regardless of the substrate and the stage of colonization.On the contrary,the maximum values of laccase activity were observed at 50%of colonization on BOS and RH,while supplementation with nitrogen and calcium sources positively affected its biosynthesis.P.ostreatus and P.eryngii cultivated on BOS supplemented with peptone at 2 and 5%w/w,synthesized significant laccase amounts,i.e.,12,165.78 and 8,624.55 U/g d.w.,respectively.Satisfactory amounts of lipase were produced,especially in substrates supplemented with sunflower 2%w/w,in quantities up to 1.42 U/g d.w.,whereas the highest lipase activity was achieved by P.eryngii on WS supplemented with corn oil at 2%w/w,with a value of 4.25 U/g d.w.being recorded.Regarding fermentation of Pleurotus species in polypropylene bags,WS and BOS supported faster colonization and shorter earliness period than RH substrates,whereas supplementation did not seem to affect these culture parameters.Furthermore,oils supplementation had a positive effect on BE of both species,with values up to 100%for P.ostreatus and 80%for P.eryngii on WS and BOS,whereas on RH the lowest BE values were detected.Morphological characteristics were not significantly affected by the additives.Results indicate the positive impact that certain additives have on mushroom productivity and production of enzymes with great financial and environmental importance.
文摘This paper considers the production of biomass of two interconnected chemostats in series with biomass mortality and a growth kinetic of the biomass described by an increasing function.A comparison is made with the productivity of a single chemostat with the same mortality rate and with volume equal to the sum of the volumes of the two chemostats.We determine the operating conditions under which the productivity of the serial configuration is greater than the productivity of the single chemostat.Moreover,the differences and similarities in the results corresponding to the case with mortality and the one without mortality,are highlighted.The mortality leads to surprising results where the productivity of a steady state where the bacteria are washed out in the first chemostat is greater than the one where the bacteria are present in both chemostats.
文摘The objective of this study is to analyze a model of competition for one resource in the chemostat with general interspecific density-dependent growth rates,taking into account the predator–prey relationship.This relationship is characterized by the fact that the prey species promotes the growth of the predator species which in turn inhibits the growth of the first species.The model is a three-dimensional system of ordinary differential equations.With the same dilution rates,the model can be reduced to a planar system where the two models have the same local and even global behavior.The existence and stability conditions of all steady states of the reduced model in the plane are determined according to the operating parameters.Using the nullcline method,we present a geometric characterization of the existence and stability of all equilibria showing the multiplicity of coexistence steady states.The bifurcation diagrams illustrate that the steady states can appear or disappear only through saddle-node or transcritical bifurcations.Moreover,the operating diagrams describe the asymptotic behavior of this system by varying the control parameters and show the effect of the inhibition of predation on the emergence of the bistability region and the reduction until the disappearance of the coexistence region by increasing this inhibition parameter.
