Frontiers in bioengineering and biotechnology, Apr 30, 2024
The black soldier fly (BSF), Hermetia illucens, is used in entomoremediation processes because it... more The black soldier fly (BSF), Hermetia illucens, is used in entomoremediation processes because its larvae can use a variety of organic residues with high efficiency. However, feed efficiencies are variable and characterized by uncertainties. Recently developed growth and metabolic performance models have predicted across different studies that BSF larvae have used 53%-58% of the feed components they have assimilated, in terms of carbon equivalents, for growth throughout their lifetime when reared on chicken feed. This is termed their average net growth efficiency. The remainder of the carbon has been lost as CO 2. However, mass balances made under similar conditions show that the weight gained by BSF larvae corresponds to only 14%-48% of the feed substrates removed, indicating substrate conversion efficiency. Both performance indicators show even greater variability if more feed substrates are considered. Feed assimilation and growth rates, costs of growth, maintenance, and larval lifespan have been shown to affect how efficiently BSF larvae convert feed into growth. The differences between average net growth efficiencies and substrate conversion efficiencies further indicate that feed is often not used optimally in entomoremediation processes and that the overall yield of such processes is not determined by larval performance alone but is the result of processes and interactions between larvae, substrates, microbes, and their physical environment. The purpose of this study is to illustrate how quantification of the metabolic performance of BSF larvae can help improve our understanding of the role of the larvae in entomoremediation processes.
This study aims to evaluate the metabolic performance, in terms of specific rates of growth and f... more This study aims to evaluate the metabolic performance, in terms of specific rates of growth and feed assimilation, as well as the cost of growth and maintenance of black soldier fly larvae, BSF, Hermetia illucens on brewery waste, a potential worldwide available resource for industrial scale insect production. Brewery waste lacks starch and thus has a nutritional profile substantially different from chicken feed, which is a well‐established and excellent starchy food source for BSF larvae. It is therefore interesting to gain insight into how BSF larvae perform on brewery waste. Larvae of the BSF were reared on chicken feed, on brewery waste and on mixtures of the two. Measurements of the weight of the larvae and their respiratory CO2 production were used to estimate metabolic performance on daily basis. The BSF larvae grew on all the substrates. They reached the highest weight on chicken feed, but their specific growth and feed assimilation rates were highest on the mixed substrates, in which the larvae also reached their maximal weight in the shortest time. Substrate‐dependent costs of growth were not observed while maintenance rates tended to be only slightly lower on the mixed substrates. Overall, the BSF larvae converted the low‐starch brewery waste and the starchy chicken feed into larval biomass about equally efficiently, although brewery waste led to smaller larvae and mixing of the two substrates enhanced feed assimilation and growth. Brewery waste seems thus a suitable resource for BSF larvae, comparable with chicken feed, with respect to their metabolic performance.
We have measured growth and respiration in black soldier fly (BSF) larvae fed with mixtures of a ... more We have measured growth and respiration in black soldier fly (BSF) larvae fed with mixtures of a low-quality substrate (degassed sludge, DS), and a high-quality substrate (chicken feed, CF) in order to elucidate how substrate quality affect larval metabolism and feed conversion into new biomass. The BSF larvae grew faster and became larger the higher the content of CF was in the substrate. Growth followed a sigmoidal curve from where the specific growth rate was determined and compared to measured specific respiration rates, in order to estimate costs of growth, maintenance metabolism, rates of feed assimilation, and net growth efficiency. Specific feed assimilation rates were similar on all substrate mixtures. Maximal specific growth rates were also affected only little unless the larvae were grown in pure DS. In contrast, the cost of growth and the maintenance metabolism were larger the higher the proportion of DS was. High specific growth rates were, in addition, sustained for shorter periods of the time the more DS was included in the substrate mixtures. In effect, higher proportions of the assimilated feed were spent on respiratory purposes instead of being converted into larval biomass and the net growth efficiency decreased the more DS was included in the substrate mixtures. We conclude that substrate quality may affect the conversion of feed into new biomass via alterations of the metabolic performance of BSF larvae and thereby the overall performance of BSF larval cultures.
Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best ef... more Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com.
Extremophiles: from biology to biotechnology , Extremophiles: from biology to biotechnology , کتا... more Extremophiles: from biology to biotechnology , Extremophiles: from biology to biotechnology , کتابخانههای دانشگاه کردستان
Highlights • Galdieria sulphuraria 074G can grow in restaurant and bakery waste hydrolysates. • S... more Highlights • Galdieria sulphuraria 074G can grow in restaurant and bakery waste hydrolysates. • Sugars and free amino acids are utilised as substrates. • Ammonium and inorganic nutrients are needed in order to maximise phycocyanin synthesis. • High concentrations of food waste hydrolysates inhibit growth.
Microbial keratinases have become a biotechnologically important subject in recent years especial... more Microbial keratinases have become a biotechnologically important subject in recent years especially for the leather industry, where they advantageously can be used as clean technology dehairing agents. Traditional dehairing processes are some of the most pollutant operation steps in leather manufacturing due to their use of lime, sulphide, and other dehairing agents, and they produce a noxious sludge. Alkaline proteases, including keratinase, collagenase, and elastase can be used to minimise the need for sulphide and reduce the organic waste load of the dehairing process. Keratinolytic proteases selectively degrade the keratin tissue in the follicles in the hides and skins and keratinolytic activity combined with only mild collagenolytic and elastolytic activities could result in a proteolytic dehairing process, which is gentle towards the proteins forming the leather. We have isolated two keratinolytic strains of Bacillus cereus named IZ-06b and IZ-06r from wool and investigated their production of keratinolytic enzymes as biotechnological dehairing agents for the leather industry. Both strains produced a mixture of keratinolytic, collagenolytic, and elastolytic activities when grown in batch culture. Concentrated mixtures of these enzymes were tried in experimental beam house processes, especially for dehairing of sheep skin and cattle hides but also their potential usage in soaking and bating were investigated. These enzymes reduced the force needed to remove hairs from the skins and hides, indicating that enzymatic preparations of these two keratinolytic bacteria are useful alternatives to present beam house chemicals and good clean technology agents for dehairing of the hides and skins.
Amino acids are transformed by nitrosation with dinitrogen trioxide into their corresponding α-hy... more Amino acids are transformed by nitrosation with dinitrogen trioxide into their corresponding α-hydroxy acids, which are separated and analysed by HPLC, and used to quantify the original amino acid concentration in samples.
Frontiers in bioengineering and biotechnology, Apr 30, 2024
The black soldier fly (BSF), Hermetia illucens, is used in entomoremediation processes because it... more The black soldier fly (BSF), Hermetia illucens, is used in entomoremediation processes because its larvae can use a variety of organic residues with high efficiency. However, feed efficiencies are variable and characterized by uncertainties. Recently developed growth and metabolic performance models have predicted across different studies that BSF larvae have used 53%-58% of the feed components they have assimilated, in terms of carbon equivalents, for growth throughout their lifetime when reared on chicken feed. This is termed their average net growth efficiency. The remainder of the carbon has been lost as CO 2. However, mass balances made under similar conditions show that the weight gained by BSF larvae corresponds to only 14%-48% of the feed substrates removed, indicating substrate conversion efficiency. Both performance indicators show even greater variability if more feed substrates are considered. Feed assimilation and growth rates, costs of growth, maintenance, and larval lifespan have been shown to affect how efficiently BSF larvae convert feed into growth. The differences between average net growth efficiencies and substrate conversion efficiencies further indicate that feed is often not used optimally in entomoremediation processes and that the overall yield of such processes is not determined by larval performance alone but is the result of processes and interactions between larvae, substrates, microbes, and their physical environment. The purpose of this study is to illustrate how quantification of the metabolic performance of BSF larvae can help improve our understanding of the role of the larvae in entomoremediation processes.
This study aims to evaluate the metabolic performance, in terms of specific rates of growth and f... more This study aims to evaluate the metabolic performance, in terms of specific rates of growth and feed assimilation, as well as the cost of growth and maintenance of black soldier fly larvae, BSF, Hermetia illucens on brewery waste, a potential worldwide available resource for industrial scale insect production. Brewery waste lacks starch and thus has a nutritional profile substantially different from chicken feed, which is a well‐established and excellent starchy food source for BSF larvae. It is therefore interesting to gain insight into how BSF larvae perform on brewery waste. Larvae of the BSF were reared on chicken feed, on brewery waste and on mixtures of the two. Measurements of the weight of the larvae and their respiratory CO2 production were used to estimate metabolic performance on daily basis. The BSF larvae grew on all the substrates. They reached the highest weight on chicken feed, but their specific growth and feed assimilation rates were highest on the mixed substrates, in which the larvae also reached their maximal weight in the shortest time. Substrate‐dependent costs of growth were not observed while maintenance rates tended to be only slightly lower on the mixed substrates. Overall, the BSF larvae converted the low‐starch brewery waste and the starchy chicken feed into larval biomass about equally efficiently, although brewery waste led to smaller larvae and mixing of the two substrates enhanced feed assimilation and growth. Brewery waste seems thus a suitable resource for BSF larvae, comparable with chicken feed, with respect to their metabolic performance.
We have measured growth and respiration in black soldier fly (BSF) larvae fed with mixtures of a ... more We have measured growth and respiration in black soldier fly (BSF) larvae fed with mixtures of a low-quality substrate (degassed sludge, DS), and a high-quality substrate (chicken feed, CF) in order to elucidate how substrate quality affect larval metabolism and feed conversion into new biomass. The BSF larvae grew faster and became larger the higher the content of CF was in the substrate. Growth followed a sigmoidal curve from where the specific growth rate was determined and compared to measured specific respiration rates, in order to estimate costs of growth, maintenance metabolism, rates of feed assimilation, and net growth efficiency. Specific feed assimilation rates were similar on all substrate mixtures. Maximal specific growth rates were also affected only little unless the larvae were grown in pure DS. In contrast, the cost of growth and the maintenance metabolism were larger the higher the proportion of DS was. High specific growth rates were, in addition, sustained for shorter periods of the time the more DS was included in the substrate mixtures. In effect, higher proportions of the assimilated feed were spent on respiratory purposes instead of being converted into larval biomass and the net growth efficiency decreased the more DS was included in the substrate mixtures. We conclude that substrate quality may affect the conversion of feed into new biomass via alterations of the metabolic performance of BSF larvae and thereby the overall performance of BSF larval cultures.
Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best ef... more Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com.
Extremophiles: from biology to biotechnology , Extremophiles: from biology to biotechnology , کتا... more Extremophiles: from biology to biotechnology , Extremophiles: from biology to biotechnology , کتابخانههای دانشگاه کردستان
Highlights • Galdieria sulphuraria 074G can grow in restaurant and bakery waste hydrolysates. • S... more Highlights • Galdieria sulphuraria 074G can grow in restaurant and bakery waste hydrolysates. • Sugars and free amino acids are utilised as substrates. • Ammonium and inorganic nutrients are needed in order to maximise phycocyanin synthesis. • High concentrations of food waste hydrolysates inhibit growth.
Microbial keratinases have become a biotechnologically important subject in recent years especial... more Microbial keratinases have become a biotechnologically important subject in recent years especially for the leather industry, where they advantageously can be used as clean technology dehairing agents. Traditional dehairing processes are some of the most pollutant operation steps in leather manufacturing due to their use of lime, sulphide, and other dehairing agents, and they produce a noxious sludge. Alkaline proteases, including keratinase, collagenase, and elastase can be used to minimise the need for sulphide and reduce the organic waste load of the dehairing process. Keratinolytic proteases selectively degrade the keratin tissue in the follicles in the hides and skins and keratinolytic activity combined with only mild collagenolytic and elastolytic activities could result in a proteolytic dehairing process, which is gentle towards the proteins forming the leather. We have isolated two keratinolytic strains of Bacillus cereus named IZ-06b and IZ-06r from wool and investigated their production of keratinolytic enzymes as biotechnological dehairing agents for the leather industry. Both strains produced a mixture of keratinolytic, collagenolytic, and elastolytic activities when grown in batch culture. Concentrated mixtures of these enzymes were tried in experimental beam house processes, especially for dehairing of sheep skin and cattle hides but also their potential usage in soaking and bating were investigated. These enzymes reduced the force needed to remove hairs from the skins and hides, indicating that enzymatic preparations of these two keratinolytic bacteria are useful alternatives to present beam house chemicals and good clean technology agents for dehairing of the hides and skins.
Amino acids are transformed by nitrosation with dinitrogen trioxide into their corresponding α-hy... more Amino acids are transformed by nitrosation with dinitrogen trioxide into their corresponding α-hydroxy acids, which are separated and analysed by HPLC, and used to quantify the original amino acid concentration in samples.
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