Pestalotiopsis sp. J63, producing a high activity of laccase, is a new marine-derived fungus isolated from the oceanic sediment of the East China Sea. Since the marine environment is oligotrophic nutrient, marine deri...Pestalotiopsis sp. J63, producing a high activity of laccase, is a new marine-derived fungus isolated from the oceanic sediment of the East China Sea. Since the marine environment is oligotrophic nutrient, marine derived fungi may use small amount of nutrients to grow and produce laccases. Agricultural residues that are mainly composed of lignin, cellulose and hemicellulose are difficult to be degraded and few microbes can take them as substrates, so they are considered as oligotrophic nutrient and have the potential to be used to produce value added products. In this study, the ability of Pestalotiopsis sp. J63 to use agricultural residues to produce laccases was tested in the submerged fermentation. The combination of 3 g·L 1maltose and 20 g·L 1rice straw was the best carbon sources and 8 g·L 1ammonium sulfate was the best nitrogen source under the condition without inducers. The effects of five inducers, the feeding time and concentration of inducer on laccase production were investigated.Adding 0.09 mmol·L 1phenol after 24 h of incubation led to high laccase activity(5089 U·L 1), while with 0.09mmol·L 1phenol in the medium and wheat bran as the nitrogen source, the laccase activity could reach 5791.7U·L 1. Native-PAGE results showed that two laccase isozymes were present in the cultures. One existed in both induced and non-induced culture filtrates, while the other was only found in the fermentation with the addition of phenol, guaiacol and veratryl alcohol.展开更多
With the high availability of agricultural wastes in Malaysia, green energy is practical to be conducted. Thus, a research on the modification of the physical conditions of the solid state culture system, specifically...With the high availability of agricultural wastes in Malaysia, green energy is practical to be conducted. Thus, a research on the modification of the physical conditions of the solid state culture system, specifically different initial moisture content, fermentation temperature, inoculums size and different percentage of carbon and nitrogen sources were conducted to compare the usage of two different lignocellulosic materials which were oil palm frond and banana petiole respectively. After using a conventional method （one factor at a time）, the optimum fermentation conditions would be a combination of 70% initial moisture content （v/w）, at 28 ~C fermentation temperature with supplementation of 1% sucrose （w/w） and 1% peptone using 1 mL of inoculum in order to achieve highest xylanase production which was 1,711.87 U/mL and 1,579.60 U/mL for oil palm frond and banana petiole respectively. It was suggested that oil palm frond showed higher xylanase production compared to banana petiole.展开更多
Maintaining the viability of probiotic microorganisms from production to consumption has long been a technological challenge for the food industry. The objectives of this study were to evaluate the in vitro interactio...Maintaining the viability of probiotic microorganisms from production to consumption has long been a technological challenge for the food industry. The objectives of this study were to evaluate the in vitro interaction between Lactobacillus acidophilus La-5 and Williopsis saturnus var. suaveolens and the effect of this yeast on acidification kinetics, viability ofLactobacillus acidophilus and post-acidification in fermented milk during refrigerated storage at 5℃. The in vitro study showed a positive interaction between the acid cell free-supernatant （CFS） ofprobiotic bacteria La-5 and the yeast. The addition of W. saturnus var. suaveolens increased the fermentation time due to consumption of the organic acids produced by L. acidophilus. During the refrigerated storage of the samples, the presence of the yeast increased the viability of L. acidophilus and reduced post-acidification. However, the mechanism of such interaction of bacteria and yeast is not fully understood.展开更多
Fermented whey （a by-product from tofu industry） has been used as a coagulant in tofu manufactures in Indonesia. This research aimed to study effects of fermented whey on coagulation efficiency and physicochemical c...Fermented whey （a by-product from tofu industry） has been used as a coagulant in tofu manufactures in Indonesia. This research aimed to study effects of fermented whey on coagulation efficiency and physicochemical characteristics of tofu, compared to other acid coagulants （acetic acid and glucono-delta-lactone （GDL）） and salt coagulants （calcium sulfate and natural gypsum）. A randomized block design with a single factor was used in this research. Fermented whey could be used as coagulant in tofu manufacturing. Physicochemical characteristics of tofu from fermented whey were not significantly difference compared to tofu from calcium salt and acid coagulants. Coagulation efficiencies （CF, TSIL TPR and TB~） of fermented whey are lower than that from calcium salt coagulants （calcium sulphate and natural gypsum）. Fermented whey showed no significant differences in tofu properties and parameters of coagulation process, compared to GDL and acetic acid.展开更多
Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpu...Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpurogenum Li-3 cultivation was for the first time performed through both batch and fed-batch processes in bioreactors. In batch process, under optimal conditions （pH 5.0, temperature 32℃, agitation speed 100 r. rain 1）, 3.55 g. L^-1 GAMG was obtained in a 2.5 L fermentor. To further enhance GAMG production, a fine fed-batch process was developed by using pH and DO as feedback parameters. Starting from 48 h, 100 m190 g-L 1 substrate Glycyrrhizin （GL） was fed each time when pH increased to above 5.0 and DO was increased to above 80%. This strategy can significantly enhance GAMG production： the achieved GL conversion was 95.34% with GAMG yield of 95.15%, and GAMG concentration was 16.62 g. L^-1 which was 5 times higher than that of batch. Then, a two-step separation strat- egy was established to separate GAMG from fermentation broth by crude extraction of 15 ml column packed with D10I resin followed by fine purification with preparative C18 chromatography. The obtained GAMG purity was 95.79%. This study provides a new insight into the industrial bioprocess of high-level GAMG production.展开更多
In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtr...In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtration column, as well as the biochemical characterization of the partial purified enzymes were investigated. P. corylophilum showed the best production in medium containing wheat bran, agro-industrial residue, without additives （egg albumin or casein）, in which peptidase activity reached 520 U mL^-1 and the enzyme displayed the optimum activity between pH range from 7 to 8 and 60 ℃. It also showed high stability in wide pH range and temperature until 45 ℃ for 60 min of incubation. On the other hand, P. waksmanii, the best production was noted in a medium containing wheat bran （95%） and casein （5%）, reaching 545 U mL^-1, with proteolytic optimum activity at pH 7.5 and 55 ℃. The enzyme was mainly stable in pH range from 8 to 9 and at temperatures until 45 ℃ for 60 rain of incubation. The peptidases secreted by both fungi were inhibited in the presence of phenylmethane sulfonyl fluoride, showing that they belong to the subclass of serine peptidases.展开更多
Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM...Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM and Accelerase 1500TM. The Cellic（R） CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic（R） CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic（R） CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation （SSF） way at 20% （w/v） solid loading. It could produce 35.76 g/L or 4.6% （v/v） of ethanol concentration and 83.67 L/ton dry matter （DM） of yield.展开更多
基金Supported by the National Natural Science Foundation of China （21036005） and Scientific and Technology Plan of Zhejiang Province （2011C33016）.
文摘Pestalotiopsis sp. J63, producing a high activity of laccase, is a new marine-derived fungus isolated from the oceanic sediment of the East China Sea. Since the marine environment is oligotrophic nutrient, marine derived fungi may use small amount of nutrients to grow and produce laccases. Agricultural residues that are mainly composed of lignin, cellulose and hemicellulose are difficult to be degraded and few microbes can take them as substrates, so they are considered as oligotrophic nutrient and have the potential to be used to produce value added products. In this study, the ability of Pestalotiopsis sp. J63 to use agricultural residues to produce laccases was tested in the submerged fermentation. The combination of 3 g·L 1maltose and 20 g·L 1rice straw was the best carbon sources and 8 g·L 1ammonium sulfate was the best nitrogen source under the condition without inducers. The effects of five inducers, the feeding time and concentration of inducer on laccase production were investigated.Adding 0.09 mmol·L 1phenol after 24 h of incubation led to high laccase activity(5089 U·L 1), while with 0.09mmol·L 1phenol in the medium and wheat bran as the nitrogen source, the laccase activity could reach 5791.7U·L 1. Native-PAGE results showed that two laccase isozymes were present in the cultures. One existed in both induced and non-induced culture filtrates, while the other was only found in the fermentation with the addition of phenol, guaiacol and veratryl alcohol.
文摘With the high availability of agricultural wastes in Malaysia, green energy is practical to be conducted. Thus, a research on the modification of the physical conditions of the solid state culture system, specifically different initial moisture content, fermentation temperature, inoculums size and different percentage of carbon and nitrogen sources were conducted to compare the usage of two different lignocellulosic materials which were oil palm frond and banana petiole respectively. After using a conventional method （one factor at a time）, the optimum fermentation conditions would be a combination of 70% initial moisture content （v/w）, at 28 ~C fermentation temperature with supplementation of 1% sucrose （w/w） and 1% peptone using 1 mL of inoculum in order to achieve highest xylanase production which was 1,711.87 U/mL and 1,579.60 U/mL for oil palm frond and banana petiole respectively. It was suggested that oil palm frond showed higher xylanase production compared to banana petiole.
文摘Maintaining the viability of probiotic microorganisms from production to consumption has long been a technological challenge for the food industry. The objectives of this study were to evaluate the in vitro interaction between Lactobacillus acidophilus La-5 and Williopsis saturnus var. suaveolens and the effect of this yeast on acidification kinetics, viability ofLactobacillus acidophilus and post-acidification in fermented milk during refrigerated storage at 5℃. The in vitro study showed a positive interaction between the acid cell free-supernatant （CFS） ofprobiotic bacteria La-5 and the yeast. The addition of W. saturnus var. suaveolens increased the fermentation time due to consumption of the organic acids produced by L. acidophilus. During the refrigerated storage of the samples, the presence of the yeast increased the viability of L. acidophilus and reduced post-acidification. However, the mechanism of such interaction of bacteria and yeast is not fully understood.
文摘Fermented whey （a by-product from tofu industry） has been used as a coagulant in tofu manufactures in Indonesia. This research aimed to study effects of fermented whey on coagulation efficiency and physicochemical characteristics of tofu, compared to other acid coagulants （acetic acid and glucono-delta-lactone （GDL）） and salt coagulants （calcium sulfate and natural gypsum）. A randomized block design with a single factor was used in this research. Fermented whey could be used as coagulant in tofu manufacturing. Physicochemical characteristics of tofu from fermented whey were not significantly difference compared to tofu from calcium salt and acid coagulants. Coagulation efficiencies （CF, TSIL TPR and TB~） of fermented whey are lower than that from calcium salt coagulants （calcium sulphate and natural gypsum）. Fermented whey showed no significant differences in tofu properties and parameters of coagulation process, compared to GDL and acetic acid.
基金Supported by the National Natural Science Foundation of China(21176028 and21506011)the National Science Fund for Distinguished Young Scholars of China(21425624)Doctoral Fund of Ministry of Education of China(20121101110050)
文摘Glycyrrhetic acid 3-O-mono-β-D-glucuronide （GAMG）, the major functional ingredient in licorice, has widespread applications in food, pharmacy and cosmetics industry. The production of GAMG through Penicillium purpurogenum Li-3 cultivation was for the first time performed through both batch and fed-batch processes in bioreactors. In batch process, under optimal conditions （pH 5.0, temperature 32℃, agitation speed 100 r. rain 1）, 3.55 g. L^-1 GAMG was obtained in a 2.5 L fermentor. To further enhance GAMG production, a fine fed-batch process was developed by using pH and DO as feedback parameters. Starting from 48 h, 100 m190 g-L 1 substrate Glycyrrhizin （GL） was fed each time when pH increased to above 5.0 and DO was increased to above 80%. This strategy can significantly enhance GAMG production： the achieved GL conversion was 95.34% with GAMG yield of 95.15%, and GAMG concentration was 16.62 g. L^-1 which was 5 times higher than that of batch. Then, a two-step separation strat- egy was established to separate GAMG from fermentation broth by crude extraction of 15 ml column packed with D10I resin followed by fine purification with preparative C18 chromatography. The obtained GAMG purity was 95.79%. This study provides a new insight into the industrial bioprocess of high-level GAMG production.
文摘In this present work, the best conditions for production of peptidases under solid state fermentation by the fungi Penicillium corylophilum and Penicillium waksmanii, partial purification using Sephadex G-75 gel filtration column, as well as the biochemical characterization of the partial purified enzymes were investigated. P. corylophilum showed the best production in medium containing wheat bran, agro-industrial residue, without additives （egg albumin or casein）, in which peptidase activity reached 520 U mL^-1 and the enzyme displayed the optimum activity between pH range from 7 to 8 and 60 ℃. It also showed high stability in wide pH range and temperature until 45 ℃ for 60 min of incubation. On the other hand, P. waksmanii, the best production was noted in a medium containing wheat bran （95%） and casein （5%）, reaching 545 U mL^-1, with proteolytic optimum activity at pH 7.5 and 55 ℃. The enzyme was mainly stable in pH range from 8 to 9 and at temperatures until 45 ℃ for 60 rain of incubation. The peptidases secreted by both fungi were inhibited in the presence of phenylmethane sulfonyl fluoride, showing that they belong to the subclass of serine peptidases.
文摘Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM and Accelerase 1500TM. The Cellic（R） CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic（R） CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic（R） CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation （SSF） way at 20% （w/v） solid loading. It could produce 35.76 g/L or 4.6% （v/v） of ethanol concentration and 83.67 L/ton dry matter （DM） of yield.
