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Moving from the linear production model to the circular economy approach is the main concern of the EU Circular Economy Action Plan. Population growth coupled with high demand for goods has led to a significant increase in solid waste, especially food waste, triggering the depletion of natural resources and the environmental burdens associated to their disposal. However, their physical, chemical and biological characteristics make them by-products with a high potential to be valorized and therefore used as resources for other industrial production models. This is the case of spent coffee grounds (SCGs), which are produced in large quantities on a daily basis. Therefore, valorization models under the approach of the biorefinery concept can be envisaged with the aims of recovering potential bioactive compounds and renewable energy. This has been the approach developed in this critical review, in which SCG recovery alternatives have been studied to obtain lignin, lipids, biofuels and phenolic compounds. In addition, a critical analysis of the outcomes of techno-economic and environmental evaluations available in the literature is included, in order to identify those indicators that provide information on the feasibility of their valorization.

The climate crisis calls for a shift from petrochemicals to bio-based products to reduce environmental consequences. Polylactic acid (PLA) is one of the most widely used biopolymers, due to its mechanical properties and renewable origin, to produce bio-based compostable plastic for food packaging. The objective of this study is to determine the environmental feasibility of a second-generation PLA production based on wheat straw; and the role of a chemical recycling plant on the environmental performance of a bioproduct at an early design stage. A holistic assessment was performed through the Life Cycle Assessment (LCA) methodology considering both attributional and consequential perspectives, through a cradle-to-grave approach. The attributional LCA results show that lactic acid production was the main contributor due to the wheat straw pre-treatment and downstream separation and purification (DSP) processes. The integration of a recycling plant leads to a significant reduction of burdens, ranging from 1.38 to 0.44 kg CO2eq in the Global Warming category. Furthermore, consequential LCA results shows that the increased demand for substitute products for activities such as feeding, fertilisation and energy generation and the indirect emissions from land use change related to the conversion of land for the cultivation of raw materials are relevant factors in the environmental effects associated with the possible implementation of straw-based bioPLA production system

The depletion of fossil resources and the climate change crisis call for an urgent shift to production pathways based on renewable and low-carbon sources. In addition, plastic pollution worldwide motivates the identification of new sources for their bio-based counterparts, which have an increasing demand. This research aims to evaluate the environmental feasibility of different cereal-based feedstocks for the production of poly(butylene succinate) (PBS), which is obtained from the polymerisation of succinic acid (SA) and 1,4 butanediol (BDO) monomers. The baseline scenario analysed corresponds to the use of wheat straw as a source of the fermentable sugars. Furthermore, five other cereal-based production routes combining first-generation (1G) feedstocks such as wheat and maize grain, and second-generation (2G) feedstocks, such as sorghum, barley straw, and maize stover, combined with wheat straw, were evaluated. The Life Cycle Assessment (LCA) methodology was used to identify the main hotspots of these valorisation routes at the early stage of the biorefinery design, considering all the burden categories provided by the ReCiPe impact method. The results showed that the straw-based PBS profile reached a Global Warming Potential of 3.43 kg CO2eq, whereas a range value from 2.34 to 7.27 kg CO2eq was estimated when wheat straw is combined with sorghum and barley straw, respectively. The pre-treatment stage represents a substantial impact on the strategy considered to produce fermentable sugars, particularly, for barley straw. Therefore, improvements are still required to reduce the energy demand and increase the sugar yield

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Nusproizvodi proizvodnje palminog ulja, i to pogača od palminih sjemenki, palmina vlakna, ljuske palminih sjemenki i prazni grozdovi palminog ploda, upotrijebljeni su za ekstrakciju polifenolnih spojeva. Među tim nusproizvodima je pogača od palminih sjemenki sadržavala najviše ukupnih fenolnih spojeva, i to 5,19 mg u g suhe tvari, izraženih kao ekvivalent galne kiseline, dok je najmanje imao prazni grozd palminog ploda, i to 1,79 mg/g. Radi optimiranja ekstrakcije fenola ispitani su sljedeći parametri: vrijeme ekstrakcije i omjer tekuće i krute tvari. Najveći ukupni udjel fenola od 5,35 mg/g pri omjeru tekuće i krute tvari od 40:1 tijekom ekstrakcije od 20 min imala je pogača od palminih sjemenki. Pomoću HPLC-DAD metode određeni su glavni fenolni spojevi iz nusprodukata proizvodnje palminog ulja. Pogača od palminih sjemenki sadržavala je najviše pirogalola, te 4-hidroksibenzojeve, galne i ferulinske kiseline. Prazni grozdovi palminog ploda i palmina vlakna bili su bogati hidroksibenzojevom kiselinom, dok je pirogalol bio dominantan sastojak ekstrakta ljuski palminih sjemenki. Svi su ekstrakti imali oksidacijsku aktivnost, koja je potvrđena DPPH analizom, te ispitana dodatkom ekstrakta suncokretovom ulju radi produljenja roka trajanja. Dodatkom 0,8 % ekstrakta pogače od palminih sjemenki povećalo se indukcijsko vrijeme suncokretovog ulja za više od 50 %. Rezultati istraživanja potvrđuju da je pogača od palminih sjemenki nusproizvod s dodanom vrijednošću koji se može upotrijebiti kao antioksidans u prehrambenoj industriji., The side streams derived from the palm oil production process, namely palm kernel cake, palm pressed fibre, palm kernel shells and empty fruit bunches, were evaluated as sources of phenolic compounds. Among these streams, kernel cake had the highest total phenolic content (in mg of gallic acid equivalents (GAE) per g of dry sample) with a value of 5.19, whereas the empty fruit bunches had the lowest value (1.79). The extraction time and liquid-to-solid ratio were investigated to optimize the phenolic extraction. Kernel cake exhibited the highest total phenolic content (5.35 mg/g) with a liquid-to-solid ratio of 40:1 during 20 min of extraction. The main phenolic compounds of the extracts deriving from all byproduct streams were also identified and quantified with HPLC-DAD. Pyrogallol, 4-hydroxybenzoic acid, gallic acid and ferulic acid were the main compounds found in kernel cake extracts. Empty fruit bunch and pressed fibre extracts were also rich in 4-hydroxybenzoic acid, while pyrogallol was the predominant compound in kernel shell extracts. All extracts showed antioxidant activity as it was indicated from the results of DPPH analysis and subsequently tested in sunflower oil aiming to prolong its shelf life. The addition of 0.8 % kernel cake extract increased the induction time of sunflower oil more than 50 %. According to the results obtained in this study, kernel cake extracts could be considered as a value-added co-product with a potential application as antioxidants in the food industry.

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U radu je prikazan razvoj novog tipa piva za tržiste, koje se dobiva vrenjem pri niskoj temperaturi u hladnjaku s pomoću imobiliziranog kvasca. Zamrznuta sladovina te stanice soja kvasca Saccharomyces cerevisiae AXAZ-1, koji je otporan na smrzavanje, imobilizirane su na cijevnom modulu i zasebno upotrijebljene za vrenje pri niskim temperaturama (2, 5 i 7 °C). Ispitan je pozitivan učinak cijevnog modula na vrenje pri niskim temperaturama, te je utvrđeno da smrznute imobilizirane stanice kvasca na cijevnom modulu bitno smanjuju brzinu vrenja u usporedbi sa smrznutim slobodnim stanicama, koje su preporučene za proizvodnju piva kod kuće. Imobilizacija je također povećala otpornost kvasca na niske temperature vrenja, pa se najniža moguća temperatura vrenja spustila s 5 na 2 °C. Pri proizvodnji visokokvalitetnog piva ispitani su sljedeći parametri: utjecaj temperature i početne koncentracije šećera na kinetiku vrenja. Analizom gotovog proizvoda potvrđeno je poboljšanje senzorskih svojstava proizvedenog piva, s niskom koncentracijom diacetila, povećanim udjelom polifenola, te poboljšanim profilom arome i bistroćom. Predloženi postupak proizvodnje piva u hladnjaku može se lako komercijalizirati za kućnu uporabu otapanjem sadržaja dvaju pakiranja, jednog sa suhom sladovinom i drugog sa suhim stanicama kvasca imobiliziranim na cijevnom modulu i otopljenim u vodi., Development of a novel directly marketable beer brewed at low temperature in a domestic refrigerator combined with yeast immobilization technology is presented in this study. Separately, freeze-dried wort and immobilized cells of the cryotolerant yeast strain Saccharomyces cerevisiae AXAZ-1 on tubular cellulose were used in low-temperature fermentation (2, 5 and 7 °C). The positive effect of tubular cellulose during low-temperature brewing was examined, revealing that freeze-dried immobilized yeast cells on tubular cellulose significantly reduced the fermentation rates in contrast to freeze-dried free cells, although they are recommended for home-made beer production. Immobilization also enhanced the yeast resistance at low-temperature fermentation, reducing the minimum brewing temperature value from 5 to 2 °C. In the case of high-quality beer production, the effect of temperature and initial sugar concentration on the fermentation kinetics were assessed. Sensory enrichment of the produced beer was confirmed by the analysis of the final products, revealing a low diacetyl concentration, together with improved polyphenol content, aroma profile and clarity. The proposed process for beer production in a domestic refrigerator can easily be commercialized and applied by dissolving the content of two separate packages in tap water; one package containing dried wort and the other dried immobilized cells on tubular cellulose suspended in tap water.

Limited data is available on feline leishmaniosis (FeL) caused by Leishmania infantum worldwide. The LeishVet group presents in this report a review of the current knowledge on FeL, the epidemiological role of the cat in L. infantum infection, clinical manifestations, and recommendations on diagnosis, treatment and monitoring, prognosis and prevention of infection, in order to standardize the management of this disease in cats. The consensus of opinions and recommendations was formulated by combining a comprehensive review of evidence-based studies and case reports, clinical experience and critical consensus discussions. While subclinical feline infections are common in areas endemic for canine leishmaniosis, clinical illness due to L. infantum in cats is rare. The prevalence rates of feline infection with L. infantum in serological or molecular-based surveys range from 0 % to more than 60 %. Cats are able to infect sand flies and, therefore, they may act as a secondary reservoir, with dogs being the primary natural reservoir. The most common clinical signs and clinicopathological abnormalities compatible with FeL include lymph node enlargement and skin lesions such as ulcerative, exfoliative, crusting or nodular dermatitis (mainly on the head or distal limbs), ocular lesions (mainly uveitis), feline chronic gingivostomatitis syndrome, mucocutaneous ulcerative or nodular lesions, hypergammaglobulinaemia and mild normocytic normochromic anaemia. Clinical illness is frequently associated with impaired immunocompetence, as in case of retroviral coinfections or immunosuppressive therapy. Diagnosis is based on serology, polymerase chain reaction (PCR), cytology, histology, immunohistochemistry (IHC) or culture. If serological testing is negative or low positive in a cat with clinical signs compatible with FeL, the diagnosis of leishmaniosis should not be excluded and additional diagnostic methods (cytology, histology with IHC, PCR, culture) should be employed. The most c

Food waste is currently generated in significant quantities worldwide. While most of this has generally few uses different from landfilling or composting, advanced valorization alternatives should be developed to maximize the value derived from such an important waste source. This contribution aims to illustrate a series of examples and current valorization strategies proposed in different countries in order to tackle the food waste issue. Proposed processing schemes involve biorefinery approaches based on both chemical and biological technologies. Important legislation aspects in different countries are also presented. (c) 2014 Society of Chemical Industry and John Wiley & Sons, Ltd

Food waste is currently generated in significant quantities worldwide. While most of this has generally few uses different from landfilling or composting, advanced valorization alternatives should be developed to maximize the value derived from such an important waste source. This contribution aims to illustrate a series of examples and current valorization strategies proposed in different countries in order to tackle the food waste issue. Proposed processing schemes involve biorefinery approaches based on both chemical and biological technologies. Important legislation aspects in different countries are also presented. (c) 2014 Society of Chemical Industry and John Wiley & Sons, Ltd

Food waste is currently generated in significant quantities worldwide. While most of this has generally few uses different from landfilling or composting, advanced valorization alternatives should be developed to maximize the value derived from such an important waste source. This contribution aims to illustrate a series of examples and current valorization strategies proposed in different countries in order to tackle the food waste issue. Proposed processing schemes involve biorefinery approaches based on both chemical and biological technologies. Important legislation aspects in different countries are also presented. (c) 2014 Society of Chemical Industry and John Wiley & Sons, Ltd

Increasing demand for fuels and chemicals, driven by factors including over-population, the threat of global warming and the scarcity of fossil resources, strains our resource system and necessitates the development of sustainable and innovative strategies for the chemical industry. Our society is currently experiencing constraints imposed by our resource system, which drives industry to increase its overall efficiency by improving existing processes or finding new uses for waste. Food supply chain waste emerged as a resource with a significant potential to be employed as a raw material for the production of fuels and chemicals given the abundant volumes globally generated, its contained diversity of functionalised chemical components and the opportunity to be utilised for higher value applications. The present manuscript is aimed to provide a general overview of the current and most innovative uses of food supply chain waste, providing a range of worldwide case-studies from around the globe. These studies will focus on examples illustrating the use of citrus peel, waste cooking oil and cashew shell nut liquid in countries such as China, the UK, Tanzania, Spain, Greece or Morocco. This work emphasises 2nd generation food waste valorisation and re-use strategies for the production of higher value and marketable products rather than conventional food waste processing (incineration for energy recovery, feed or composting) while highlighting issues linked to the use of food waste as a sustainable raw material. The influence of food regulations on food supply chain waste valorisation will also be addressed as well as our society's behavior towards food supply chain waste. "There was no ways of dealing with it that have not been known for thousands of years. These ways are essentially four: dumping it, burning it, converting it into something that can be used again, and minimizing the volume of material goods-future garbage-that is produced in the first place." William Ra

Increasing demand for fuels and chemicals, driven by factors including over-population, the threat of global warming and the scarcity of fossil resources, strains our resource system and necessitates the development of sustainable and innovative strategies for the chemical industry. Our society is currently experiencing constraints imposed by our resource system, which drives industry to increase its overall efficiency by improving existing processes or finding new uses for waste. Food supply chain waste emerged as a resource with a significant potential to be employed as a raw material for the production of fuels and chemicals given the abundant volumes globally generated, its contained diversity of functionalised chemical components and the opportunity to be utilised for higher value applications. The present manuscript is aimed to provide a general overview of the current and most innovative uses of food supply chain waste, providing a range of worldwide case-studies from around the globe. These studies will focus on examples illustrating the use of citrus peel, waste cooking oil and cashew shell nut liquid in countries such as China, the UK, Tanzania, Spain, Greece or Morocco. This work emphasises 2nd generation food waste valorisation and re-use strategies for the production of higher value and marketable products rather than conventional food waste processing (incineration for energy recovery, feed or composting) while highlighting issues linked to the use of food waste as a sustainable raw material. The influence of food regulations on food supply chain waste valorisation will also be addressed as well as our society's behavior towards food supply chain waste. "There was no ways of dealing with it that have not been known for thousands of years. These ways are essentially four: dumping it, burning it, converting it into something that can be used again, and minimizing the volume of material goods-future garbage-that is produced in the first place." William Ra

Preservation, risk of contamination, transportation and storage costs (e.g. refrigeration) are the main problems associated with wet, active starter cultures such as yeast. To deal with these aspects, drying of commercial cultures is required. A thermally dried biocatalyst has been prepared by immobilization of the psychrotolerant yeast strain Saccharomyces cerevisiae AXAZ-1 on delignified brewer’s spent grains, followed by simple thermal drying or by air stream at 30 and 35 °C. Repeated batch fermentations of grape must (11.5 °Be, corresponding to 196 g/L of fermentable sugar) using the dried biocatalysts were performed at successively reduced temperatures (15, 10 and 5 °C). The fermented samples were analyzed for residual sugar, alcohol and free cell concentrations. The alcohol yield, alcohol productivity and sugar conversion were calculated in order to estimate the optimum conditions of drying. The volatile constituents in the produced wines were analysed by GC analysis. The results showed that drying of immobilized cells by the proposed techniques did not affect their viability and fermentative activity. High alcohol productivity, increased esters and lower concentrations of higher alcohols obtained by low-temperature fermentation using the dried biocatalysts indicate a potential improvement of product quality., Konzerviranje, rizik od onečišćenja, te cijena transporta i skladištenja (npr. hlađenja) najčešći su problemi pri korištenju vlažnih, aktivnih starter-kultura, tj. kvasaca. Stoga komercijalne kulture kvasaca treba osušiti. Sušeni je biokatalizator pripremljen imobilizacijom psihrotolerantnoga soja kvasca Saccharomyces cerevisiae AXAZ-1 na pivskom tropu, iz kojeg je prethodno uklonjen lignin, a zatim sušenjem toplinom ili strujom zraka pri 30 i 35 °C. Pomoću tako pripremljenog kvasca uspješno je provedeno nekoliko uzastopnih šaržnih postupaka vrenja mošta (11,5 °Be, proporcionalno 196 g/L fermentabilnog šećera) pri nižim temperaturama (15, 10 i 5 °C). Ispitana je koncentracija preostalog šećera, dobivenog alkohola i slobodnih stanica u fermentiranim uzorcima. Da bi se procijenili optimalni uvjeti sušenja, izračunati su ovi parametri: udio i produktivnost alkohola te konverzija šećera. Volatilni su sastojci vina analizirani plinskom kromatografijom. Rezultati pokazuju da sušenje imobiliziranih stanica kvasca predloženim metodama ne utječe na njegovu vitalnost i fermentacijsku aktivnost. Kakvoća se proizvoda može poboljšati korištenjem sušenih stanica kvasca pri nižim temperaturama, što je uočeno iz većeg udjela alkohola, veće koncentracije estera i manje koncentracije viših alkohola u vinu.

A novel wheat-based bioprocess for the production of a nutrient-complete feedstock for the fermentative succinic acid production by Actinobacillus succinogenes has been developed. Wheat was fractionated into bran, middlings and flour. The bran fraction,which would normally be a waste product of the wheat milling industry, was used as the sole medium in two solid-state fermentations (SSF) of Aspergillus awamori and Aspergillus oryzae that produce enzyme complexes rich in amylolytic and proteolytic enzymes, respectively. The resulting fermentation solids were then used as crude enzyme sources, by adding directly to an aqueous suspension of milled bran and middlings fractions (wheat flour milling by-products) to generate a hydrolysate containing over 95g/L glucose, 25g/L maltose and 300mg/L free amino nitrogen (FAN). This hydrolysate was then used as the sole medium for A. succinogenes fermentations, which led to the production of 50.6g/L succinic acid. Supplementation of the medium with yeast extract did not significantly improve succinic acid production though increasing the inoculum concentration to 20% did result in the production of 62.1 g/L succinic acid. Results indicated that A. succinogenes cells were able to utilise glucose and maltose in the wheat hydrolysate for cell growth and succinic acid production. The proposed process could be potentially integrated into a wheat-milling process to upgrade the wheat flour milling by-products (WFMB) into succinic acid, one of the future platform chemicals of a sustainable chemical industry. (C) 2009 Elsevier B.V. All rights reserved.

A novel alternative methodology (direct crystallisation) to the traditional calcium precipitation to obtain succinic acid (SA) from defined and wheat-based fermentation broths is reported. SA crystals were successfully recovered from fermentation broths (FB) using this method. A higher SA crystal purity (95%) and yield (70%) were obtained in the direct crystallisation method compared to a slightly modified traditional calcium precipitation method (90% and 24%, respectively). Chemical transformations (e.g. esterifications) to high-added value derivatives of both recovered SA crystals were then investigated using a range of solid acids including our acidic tunable mesoporous carbonaceous materials denoted as Starbon® acids. Results showed that SA crystals could be successfully converted into mono- and diesters in high yields and selectivities employing solid acids regardless of the reaction conditions. The order of reactivity was found to be: pure SA crystals > SA crystals from defined FB > FB SA crystals. Results demonstrate that SA can be effectively purified from actual fermentation broths, showing the importance of integrating the fermentation and downstream processing to optimise the fermentative production of SA and its chemical transformations to produce high-added value derivatives. © 2009 The Royal Society of Chemistry.

A novel wheat-based bioprocess for the production of a nutrient-complete feedstock for the fermentative succinic acid production by Actinobacillus succinogenes has been developed. Wheat was fractionated into bran, middlings and flour. The bran fraction,which would normally be a waste product of the wheat milling industry, was used as the sole medium in two solid-state fermentations (SSF) of Aspergillus awamori and Aspergillus oryzae that produce enzyme complexes rich in amylolytic and proteolytic enzymes, respectively. The resulting fermentation solids were then used as crude enzyme sources, by adding directly to an aqueous suspension of milled bran and middlings fractions (wheat flour milling by-products) to generate a hydrolysate containing over 95g/L glucose, 25g/L maltose and 300mg/L free amino nitrogen (FAN). This hydrolysate was then used as the sole medium for A. succinogenes fermentations, which led to the production of 50.6g/L succinic acid. Supplementation of the medium with yeast extract did not significantly improve succinic acid production though increasing the inoculum concentration to 20% did result in the production of 62.1 g/L succinic acid. Results indicated that A. succinogenes cells were able to utilise glucose and maltose in the wheat hydrolysate for cell growth and succinic acid production. The proposed process could be potentially integrated into a wheat-milling process to upgrade the wheat flour milling by-products (WFMB) into succinic acid, one of the future platform chemicals of a sustainable chemical industry. (C) 2009 Elsevier B.V. All rights reserved.

A novel alternative methodology (direct crystallisation) to the traditional calcium precipitation to obtain succinic acid (SA) from defined and wheat-based fermentation broths is reported. SA crystals were successfully recovered from fermentation broths (FB) using this method. A higher SA crystal purity (95%) and yield (70%) were obtained in the direct crystallisation method compared to a slightly modified traditional calcium precipitation method (90% and 24%, respectively). Chemical transformations (e.g. esterifications) to high-added value derivatives of both recovered SA crystals were then investigated using a range of solid acids including our acidic tunable mesoporous carbonaceous materials denoted as Starbon® acids. Results showed that SA crystals could be successfully converted into mono- and diesters in high yields and selectivities employing solid acids regardless of the reaction conditions. The order of reactivity was found to be: pure SA crystals > SA crystals from defined FB > FB SA crystals. Results demonstrate that SA can be effectively purified from actual fermentation broths, showing the importance of integrating the fermentation and downstream processing to optimise the fermentative production of SA and its chemical transformations to produce high-added value derivatives. © 2009 The Royal Society of Chemistry.

A novel wheat-based bioprocess for the production of a nutrient-complete feedstock for the fermentative succinic acid production by Actinobacillus succinogenes has been developed. Wheat was fractionated into bran, middlings and flour. The bran fraction,which would normally be a waste product of the wheat milling industry, was used as the sole medium in two solid-state fermentations (SSF) of Aspergillus awamori and Aspergillus oryzae that produce enzyme complexes rich in amylolytic and proteolytic enzymes, respectively. The resulting fermentation solids were then used as crude enzyme sources, by adding directly to an aqueous suspension of milled bran and middlings fractions (wheat flour milling by-products) to generate a hydrolysate containing over 95g/L glucose, 25g/L maltose and 300mg/L free amino nitrogen (FAN). This hydrolysate was then used as the sole medium for A. succinogenes fermentations, which led to the production of 50.6g/L succinic acid. Supplementation of the medium with yeast extract did not significantly improve succinic acid production though increasing the inoculum concentration to 20% did result in the production of 62.1 g/L succinic acid. Results indicated that A. succinogenes cells were able to utilise glucose and maltose in the wheat hydrolysate for cell growth and succinic acid production. The proposed process could be potentially integrated into a wheat-milling process to upgrade the wheat flour milling by-products (WFMB) into succinic acid, one of the future platform chemicals of a sustainable chemical industry. (C) 2009 Elsevier B.V. All rights reserved.

A novel alternative methodology (direct crystallisation) to the traditional calcium precipitation to obtain succinic acid (SA) from defined and wheat-based fermentation broths is reported. SA crystals were successfully recovered from fermentation broths (FB) using this method. A higher SA crystal purity (95%) and yield (70%) were obtained in the direct crystallisation method compared to a slightly modified traditional calcium precipitation method (90% and 24%, respectively). Chemical transformations (e.g. esterifications) to high-added value derivatives of both recovered SA crystals were then investigated using a range of solid acids including our acidic tunable mesoporous carbonaceous materials denoted as Starbon® acids. Results showed that SA crystals could be successfully converted into mono- and diesters in high yields and selectivities employing solid acids regardless of the reaction conditions. The order of reactivity was found to be: pure SA crystals > SA crystals from defined FB > FB SA crystals. Results demonstrate that SA can be effectively purified from actual fermentation broths, showing the importance of integrating the fermentation and downstream processing to optimise the fermentative production of SA and its chemical transformations to produce high-added value derivatives. © 2009 The Royal Society of Chemistry.

In this study, a novel generic feedstock production strategy based on solid-state fermentation (SSF) has been developed and applied to the fermentative production of succinic acid. Wheat was fractionated into bran, gluten and gluten-free flour by milling and gluten extraction processes. The bran, which would normally be a waste product of the wheat milling industry, was used to produce glucoamylase and protease enzymes via SSF using Aspergillus awamori and Aspergillus oryzae, respectively. The resulting solutions were separately utilised for the hydrolysis of gluten-free flour and gluten to generate a glucose-rich stream of over 140 g l-1 glucose and a nitrogen-rich stream of more than 3.5 g l-1 free amino nitrogen. A microbial feedstock consisting of these two streams contained all the essential nutrients required for succinic acid fermentations using Actinobacillus succinogenes. In a fermentation using only the combined hydrolysate streams, around 22 g l-1 succinic acid was produced. The addition of MgCO3 into the wheat-derived medium improved the succinic acid production further to more than 64 g l-1. These results demonstrate the SSF-based strategy is a successful approach for the production of a generic feedstock from wheat, and that this feedstock can be efficiently utilised for succinic acid production. © 2008 Elsevier Ltd. All rights reserved.

The inhibition of substrate and products on the growth of Actinobacillus succinogenes in fermentation using glucose as the major carbon source was studied. A. succinogenes tolerated up to 143 g/L glucose and cell growth was completely inhibited with glucose concentration over 158 g/L. Significant decrease in succinic acid yield and prolonged lag phase were observed with glucose concentration above 100 g/L. Among the end-products investigated, formate was found to have the most inhibitory effect on succinic acid fermentation. The critical concentrations of acetate, ethanol, formate, pyruvate and succinate were 46, 42, 16, 74, 104 g/L, respectively. A growth kinetic model considering both substrate and product inhibition is proposed, which adequately simulates batch fermentation kinetics using both semi-defined and wheat-derived media. The model accurately describes the inhibitory kinetics caused by both externally added chemicals and the same chemicals produced during fermentation. This paper provides key insights into the improvement of succinic acid production and the modelling of inhibition kinetics. © 2008 Elsevier B.V. All rights reserved.

In this study, a novel generic feedstock production strategy based on solid-state fermentation (SSF) has been developed and applied to the fermentative production of succinic acid. Wheat was fractionated into bran, gluten and gluten-free flour by milling and gluten extraction processes. The bran, which would normally be a waste product of the wheat milling industry, was used to produce glucoamylase and protease enzymes via SSF using Aspergillus awamori and Aspergillus oryzae, respectively. The resulting solutions were separately utilised for the hydrolysis of gluten-free flour and gluten to generate a glucose-rich stream of over 140 g l-1 glucose and a nitrogen-rich stream of more than 3.5 g l-1 free amino nitrogen. A microbial feedstock consisting of these two streams contained all the essential nutrients required for succinic acid fermentations using Actinobacillus succinogenes. In a fermentation using only the combined hydrolysate streams, around 22 g l-1 succinic acid was produced. The addition of MgCO3 into the wheat-derived medium improved the succinic acid production further to more than 64 g l-1. These results demonstrate the SSF-based strategy is a successful approach for the production of a generic feedstock from wheat, and that this feedstock can be efficiently utilised for succinic acid production. © 2008 Elsevier Ltd. All rights reserved.

The inhibition of substrate and products on the growth of Actinobacillus succinogenes in fermentation using glucose as the major carbon source was studied. A. succinogenes tolerated up to 143 g/L glucose and cell growth was completely inhibited with glucose concentration over 158 g/L. Significant decrease in succinic acid yield and prolonged lag phase were observed with glucose concentration above 100 g/L. Among the end-products investigated, formate was found to have the most inhibitory effect on succinic acid fermentation. The critical concentrations of acetate, ethanol, formate, pyruvate and succinate were 46, 42, 16, 74, 104 g/L, respectively. A growth kinetic model considering both substrate and product inhibition is proposed, which adequately simulates batch fermentation kinetics using both semi-defined and wheat-derived media. The model accurately describes the inhibitory kinetics caused by both externally added chemicals and the same chemicals produced during fermentation. This paper provides key insights into the improvement of succinic acid production and the modelling of inhibition kinetics. © 2008 Elsevier B.V. All rights reserved.

In this study, a novel generic feedstock production strategy based on solid-state fermentation (SSF) has been developed and applied to the fermentative production of succinic acid. Wheat was fractionated into bran, gluten and gluten-free flour by milling and gluten extraction processes. The bran, which would normally be a waste product of the wheat milling industry, was used to produce glucoamylase and protease enzymes via SSF using Aspergillus awamori and Aspergillus oryzae, respectively. The resulting solutions were separately utilised for the hydrolysis of gluten-free flour and gluten to generate a glucose-rich stream of over 140 g l-1 glucose and a nitrogen-rich stream of more than 3.5 g l-1 free amino nitrogen. A microbial feedstock consisting of these two streams contained all the essential nutrients required for succinic acid fermentations using Actinobacillus succinogenes. In a fermentation using only the combined hydrolysate streams, around 22 g l-1 succinic acid was produced. The addition of MgCO3 into the wheat-derived medium improved the succinic acid production further to more than 64 g l-1. These results demonstrate the SSF-based strategy is a successful approach for the production of a generic feedstock from wheat, and that this feedstock can be efficiently utilised for succinic acid production. © 2008 Elsevier Ltd. All rights reserved.

The biosynthesis of succinic acid from wheat flour was investigated in a two-stage bio-process. In the first stage, wheat flour was converted into a generic microbial feedstock either by fungal fermentation alone or by combining fungal fermentation for enzyme and fungal bio-mass production with subsequent flour hydrolysis and fungal autolysis. In the second stage, the generic feedstock was converted into succinic acid by bacterial fermentation by Actinobacillus succinogenes. Direct fermentation of the generic feedstock produced by fungal fermentation alone resulted in a lower succinic acid production, probably due to the low glucose and nitrogen concentrations in the fungal broth filtrate. In the second feedstock production strategy, flour hydrolysis conducted by mixing fungal broth filtrate with wheat flour generated a glucose-rich stream, while the fungal bio-mass was subjected to autolysis for the production of a nutrient-rich stream. The possibility of replacing a commercial semi-defined medium by these two streams was investigated sequentially. A. succinogenes fermentation using only the wheat-derived feedstock resulted in a succinic acid concentration of almost 16 g l -1 with an overall yield of 0.19 g succinic acid per g wheat flour. These results show that a wheat-based bio-refinery employing coupled fungal fermentation and subsequent flour hydrolysis and fungal autolysis can lead to a bacterial feedstock for the efficient production of succinic acid. © 2007 Springer-Verlag.

The biosynthesis of succinic acid from wheat flour was investigated in a two-stage bio-process. In the first stage, wheat flour was converted into a generic microbial feedstock either by fungal fermentation alone or by combining fungal fermentation for enzyme and fungal bio-mass production with subsequent flour hydrolysis and fungal autolysis. In the second stage, the generic feedstock was converted into succinic acid by bacterial fermentation by Actinobacillus succinogenes. Direct fermentation of the generic feedstock produced by fungal fermentation alone resulted in a lower succinic acid production, probably due to the low glucose and nitrogen concentrations in the fungal broth filtrate. In the second feedstock production strategy, flour hydrolysis conducted by mixing fungal broth filtrate with wheat flour generated a glucose-rich stream, while the fungal bio-mass was subjected to autolysis for the production of a nutrient-rich stream. The possibility of replacing a commercial semi-defined medium by these two streams was investigated sequentially. A. succinogenes fermentation using only the wheat-derived feedstock resulted in a succinic acid concentration of almost 16 g l -1 with an overall yield of 0.19 g succinic acid per g wheat flour. These results show that a wheat-based bio-refinery employing coupled fungal fermentation and subsequent flour hydrolysis and fungal autolysis can lead to a bacterial feedstock for the efficient production of succinic acid. © 2007 Springer-Verlag.

The biosynthesis of succinic acid from wheat flour was investigated in a two-stage bio-process. In the first stage, wheat flour was converted into a generic microbial feedstock either by fungal fermentation alone or by combining fungal fermentation for enzyme and fungal bio-mass production with subsequent flour hydrolysis and fungal autolysis. In the second stage, the generic feedstock was converted into succinic acid by bacterial fermentation by Actinobacillus succinogenes. Direct fermentation of the generic feedstock produced by fungal fermentation alone resulted in a lower succinic acid production, probably due to the low glucose and nitrogen concentrations in the fungal broth filtrate. In the second feedstock production strategy, flour hydrolysis conducted by mixing fungal broth filtrate with wheat flour generated a glucose-rich stream, while the fungal bio-mass was subjected to autolysis for the production of a nutrient-rich stream. The possibility of replacing a commercial semi-defined medium by these two streams was investigated sequentially. A. succinogenes fermentation using only the wheat-derived feedstock resulted in a succinic acid concentration of almost 16 g l -1 with an overall yield of 0.19 g succinic acid per g wheat flour. These results show that a wheat-based bio-refinery employing coupled fungal fermentation and subsequent flour hydrolysis and fungal autolysis can lead to a bacterial feedstock for the efficient production of succinic acid. © 2007 Springer-Verlag.

In the Satake Centre for Grain Process Engineering we are developing cereal-based biorefining strategies for the production of biofuels, biodegradable plastics and platform chemicals. Cereal grains are complex biological entities and we target the exploitation of all cereal components providing both value-added end-products and precursors for chemical synthesis. Hydrolysis of natural polymers (e.g. starch, protein) contained in cereals requires supply of a range of hydrolytic enzymes (e.g. amylase, protease), which are produced by fungal bioconversions. On-site production of these enzymes would result in the production of a high amount of fungal biomass. Fungal autolysis can be used to bioconvert this low-cost byproduct into a nutrient-rich supplement (fungal extract) for microbial bioconversions. Mixing fungal extracts with cereal hydrolysates results in nutrient-complete microbial feedstocks. Optimising the exploitation of protein in cereal grains would enable the provision of optimum amounts of free amino acids and peptides to subsequent microbial bioconversions and the extraction of the remaining protein as a value-added co-product with various current (food) and potential (biodegradable plastics) market outlets. The use of amino acids and peptides would enhance productivities (e.g. polyhydroxybutyrate, succinic acid) and, in certain cases, production yields (e.g. polyhydroxybutyrate) improving significantly current fermentation practices that exploit only the starch component in cereal grains. In addition, the exploitation of all cereal components and low-cost by-product streams produced in a cereal-based biorefinery will result in waste minimisation and maximisation of carbon as well as other nutrient utilisation from the original cereal grain. This work will present different feedstock formulation strategies based on the production of wheat hydrolysates and fungal extracts for the microbial production of polyhydroxybutyrate and succinic acid.

In the Satake Centre for Grain Process Engineering we are developing cereal-based biorefining strategies for the production of biofuels, biodegradable plastics and platform chemicals. Cereal grains are complex biological entities and we target the exploitation of all cereal components providing both value-added end-products and precursors for chemical synthesis. Hydrolysis of natural polymers (e.g. starch, protein) contained in cereals requires supply of a range of hydrolytic enzymes (e.g. amylase, protease), which are produced by fungal bioconversions. On-site production of these enzymes would result in the production of a high amount of fungal biomass. Fungal autolysis can be used to bioconvert this low-cost byproduct into a nutrient-rich supplement (fungal extract) for microbial bioconversions. Mixing fungal extracts with cereal hydrolysates results in nutrient-complete microbial feedstocks. Optimising the exploitation of protein in cereal grains would enable the provision of optimum amounts of free amino acids and peptides to subsequent microbial bioconversions and the extraction of the remaining protein as a value-added co-product with various current (food) and potential (biodegradable plastics) market outlets. The use of amino acids and peptides would enhance productivities (e.g. polyhydroxybutyrate, succinic acid) and, in certain cases, production yields (e.g. polyhydroxybutyrate) improving significantly current fermentation practices that exploit only the starch component in cereal grains. In addition, the exploitation of all cereal components and low-cost by-product streams produced in a cereal-based biorefinery will result in waste minimisation and maximisation of carbon as well as other nutrient utilisation from the original cereal grain. This work will present different feedstock formulation strategies based on the production of wheat hydrolysates and fungal extracts for the microbial production of polyhydroxybutyrate and succinic acid.

In the Satake Centre for Grain Process Engineering we are developing cereal-based biorefining strategies for the production of biofuels, biodegradable plastics and platform chemicals. Cereal grains are complex biological entities and we target the exploitation of all cereal components providing both value-added end-products and precursors for chemical synthesis. Hydrolysis of natural polymers (e.g. starch, protein) contained in cereals requires supply of a range of hydrolytic enzymes (e.g. amylase, protease), which are produced by fungal bioconversions. On-site production of these enzymes would result in the production of a high amount of fungal biomass. Fungal autolysis can be used to bioconvert this low-cost byproduct into a nutrient-rich supplement (fungal extract) for microbial bioconversions. Mixing fungal extracts with cereal hydrolysates results in nutrient-complete microbial feedstocks. Optimising the exploitation of protein in cereal grains would enable the provision of optimum amounts of free amino acids and peptides to subsequent microbial bioconversions and the extraction of the remaining protein as a value-added co-product with various current (food) and potential (biodegradable plastics) market outlets. The use of amino acids and peptides would enhance productivities (e.g. polyhydroxybutyrate, succinic acid) and, in certain cases, production yields (e.g. polyhydroxybutyrate) improving significantly current fermentation practices that exploit only the starch component in cereal grains. In addition, the exploitation of all cereal components and low-cost by-product streams produced in a cereal-based biorefinery will result in waste minimisation and maximisation of carbon as well as other nutrient utilisation from the original cereal grain. This work will present different feedstock formulation strategies based on the production of wheat hydrolysates and fungal extracts for the microbial production of polyhydroxybutyrate and succinic acid.

Kvasci su poznati čovjeku vec tisućama godina jer se koriste u tradicionalnim fermentacijskim procesima dobivanja vina, piva i kruha. Danas se oni koriste i kao alternativni izvori visokovrijednih proteina, enzima i vitamina, imaju brojnu primjenu u proizvodnji zdravstveno korisne hrane kao aditivi, regulatori i sastojci arome, u proizvodnji mikrobioloških podloga i ekstrakata, te kao krmivo. Suvremena znanstvena dostignuća omogućuju izolaciju, izradu i industrijsku proizvodnju novih sojeva kvasaca koji ispunjavaju posebne zahtjeve prehrambene industrije. U radu su istaknuti tipovi industrijskih prehrambenih kvasaca, procesi njihove proizvodnje i sirovine. Također se raspravlja o metabolizmu kvasca, s obzirom na utrošak ugljikohidrata, hranjiva te nova dostignuća u njihovu istraživanju., Yeasts have been known to humans for thousands of years as they have been used in traditional fermentation processes like wine, beer and bread making. Today, yeasts are also used as alternative sources of high nutritional value proteins, enzymes and vitamins, and have numerous applications in the health food industry as food additives, conditioners and flavouring agents, for the production of microbiology media and extracts, as well as livestock feeds. Modern scientific advances allow the isolation, construction and industrial production of new yeast strains to satisfy the specific demands of the food industry. Types of commercial food grade yeasts, industrial production processes and raw materials are highlighted. Aspects of yeast metabolism, with respect to carbohydrate utilization, nutritional aspects and recent research advances are also discussed.