Side Stream Research Articles

Trophic interactions shape the spatial organization of medium-chain carboxylic acid producing granular biofilm communities.

Granular biofilms producing medium-chain carboxylic acids (MCCA) from carbohydrate-rich industrial feedstocks harbor highly streamlined communities converting sugars to MCCA either directly or via lactic acid as intermediate. We investigated the spatial organization and growth activity patterns of MCCA producing granular biofilms grown on an industrial side stream to test (i) whether key functional guilds (lactic acid producing Olsenella and MCCA producing Oscillospiraceae) stratified in the biofilm based on substrate usage, and (ii) whether spatial patterns of growth activity shaped the unique, lenticular morphology of these biofilms. First, three novel isolates (one Olsenella and two Oscillospiraceae species) representing over half of the granular biofilm community were obtained and used to develop FISH probes, revealing that key functional guilds were not stratified. Instead, the outer 150-500 µm of the granular biofilm consisted of a well-mixed community of Olsenella and Oscillospiraceae, while deeper layers were made up of other bacteria with lower activities. Second, nanoSIMS analysis of 15N incorporation in biofilms grown in normal and lactic acid amended conditions suggested Oscillospiraceae switched from sugars to lactic acid as substrate. This suggests competitive-cooperative interactions may govern the spatial organization of these biofilms, and suggests that optimizing biofilm size may be a suitable process engineering strategy. Third, growth activities were similar in the polar and equatorial biofilm peripheries, leaving the mechanism behind the lenticular biofilm morphology unexplained. Physical processes (e.g., shear hydrodynamics, biofilm life cycles) may have contributed to lenticular biofilm development. Together, this study develops an ecological framework of MCCA-producing granular biofilms that informs bioprocess development.

Evaluation of heavy metals, mycotoxins and mineral bioaccessibility through in vitro static digestion models of rainbow trout (Oncorhynchus mykiss) and sole (Dover sole) side stream extracts obtained by pressurized liquid extraction.

The recovery of antioxidants and minerals as well as the content of contaminants of rainbow trout and sole side streams (head, skin and viscera) extracts obtained by pressurized liquid extraction (PLE) were evaluated. Then, the effect of the gastrointestinal digestion was tested. No mycotoxins were detected in the extracts, while heavy metals contents (mg/kg) were up to 2.9 (As), 0.054 (Cd), 0.16 (Hg) and 0.073 (Pb), being below maximum legislated limits. A positive effect of PLE was found for the antioxidant capacity recovery, being the oxygen radical capacity of sole head and skin extracts significantly enhanced after digestion (∼3.8 times). PLE significantly increased Mg, Fe, Zn, Se and P (KPLE>1) contents of rainbow trout side streams, Zn (KPLE5.97) and Fe (KPLE 2.80) of head sole and Mg, Se and P of all samples. Moreover, Mg, Ca and Fe bioaccessibility was lower in all sole extracts compared to rainbow trout.

Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant

AbstractThe present work aimed to study the mainstream feasibility of the deammonifying sludge of side stream of municipal wastewater treatment plant (MWWTP) in Kaster, Germany. For this purpose, the deammonifying sludge available at the side stream was investigated for nitrogen (N) removal with respect to the operational factors temperature (15–30°C), pH value (6.0–8.0) and chemical oxygen demand (COD)/N ratio (≤1.5–6.0). The highest and lowest N‐removal rates of 0.13 and 0.045 kg/(m3 d) are achieved at 30 and 15°C, respectively. Different conditions of pH and COD/N ratios in the SBRs of Partial nitritation/anammox (PN/A) significantly influenced both the metabolic processes and associated N‐removal rates. The scientific insights gained from the current work signifies the possibility of mainstream PN/A at WWTPs. The current study forms a solid basis of operational window for the upcoming semi‐technical trails to be conducted prior to the full‐scale mainstream PN/A at WWTP Kaster and WWTPs globally.

Valorisation of Side Stream Products through Green Approaches: The Rapeseed Meal Case.

Rapeseed meal (RSM) is a by-product of rapeseed oil extraction and is a rich source of bioactive compounds, including proteins and antioxidants. This study compared two methods for extracting antioxidants from RSM: conventional ethanol Soxhlet extraction and supercritical CO2 extraction. These procedures were applied to both native RSM and RSM after protein removal to evaluate their bio-compound composition and potential applications. HPLC-DAD, NMR, and GC/MS analyses revealed a rich polyphenolic profile in the extracts, including the presence of sinapic acid. The concentration of sinapic acid varied depending on the extraction method used. The anti-radical activity of the extracts was also analysed using the DPPH assay, which confirmed the potential of RSM as a source of antioxidants for use in cosmetics, food, and pharmaceutical formulations.

Unraveling the potential and constraints associated with corn steep liquor as a nutrient source for industrial fermentations.

Costly complex media components such as yeast extract and peptone are still widely used in industrial bioprocesses, despite their ill-defined composition. Side stream products such as corn steep liquor (CSL) present a compelling economical alternative that contains valuable nutrients required for microbial growth, that is, nitrogen and amino acids, but also vitamins, trace elements, and other minerals. However, as a side stream product, CSL may be subject to batch-to-batch variations and compositional heterogeneity. In this study, the Respiration Activity MOnitoring System designed for shake flasks (RAMOS) and 96-well microtiter plates (μTOM) were applied to investigate the potential and constraints of CSL utilization for two model microorganisms: E. coli and B. subtilis. Considering the dry substance content of complex nutrients involved, CSL-based media are more efficient in biomass production than the common lysogeny broth (LB) medium, containing 5 g/L yeast extract, 10 g/L peptone, and 5 g/L NaCl. At a glucose to CSL (glucose/CSL, g/g) ratio of 1/1 (g/g) and 2/1 (g/g), a secondary substrate limitation occurred in E. coli and B. subtilis cultivations, respectively. The study sheds light on differences in the metabolic activity of the two applied model organisms between varying CSL batches, which relate to CSL origin and production process, as well as the effect of targeted nutrient supplementation. Through a targeted nutrient supplementation, the most limiting component of the CSL-glucose medium used for these applied model microorganisms was identified to be ammonium nitrogen. This study proves the suitability of CSL as an alternative nutrient source for E. coli and B. subtilis. The RAMOS and μTOM technique detected differences between CSL batches, allowing easy and early identification of varying batches. A consistent performance of the CSL batches in E. coli and B. subtilis cultivations was demonstrated.

A preliminary appraisal for utilizing abandoned industrial side streams as alternatives to cement within radiation protection applications

Recently, there has been arising a severe alert regarding climate crisis all over the world. As industrial production capacities have been soaring every passing day, the primary sources of the earth's crust have been depleting like there is no tomorrow. Sustainable and greener suggestions should be followed to overcome the upcoming catastrophic climate change. With this motivation, cement material, whose influence on global warming is excessive, has been studied to be replaced by alternative material systems in different application areas, and radiation shielding applications may be regarded as one of these emerging fields. In this study, the authors were motivated to replace ordinary Portland cement (OPC) with alternative side streams (SS) that have accumulated in nature without any benefits. First, the high-quantity SS were determined and presented as follows: fly ash (FA), blast furnace slag (BFS), red mud (RM), electric arc furnace slag (EAFS), fayalite slag (FS), rice husk ash (RHA), silica fume (SF), ferrochrome slag (FS), and copper mining tailings (CMT). Each side stream's average chemical compositions were obtained, and their theoretical density values were calculated. After that, the theoretical radiation shielding properties were assessed using Phy-X/PSD software within the 0.15–15 MeV photon energy range. Some essential parameters such as linear attenuation coefficient (LAC), half-value layer (HVL), effective atomic number (Zeff), radiation protection efficiency (RPE), and build-up factors (EBF and EABF) paved the way for comparing SS with OPC material. The results for radiation protection demonstrated that high-density-oxide-containing SS like RM, FS, and EAFS could replace OPC material with a good performance. Owing to this replacement, the authors strongly believe that the future can be sustained in a more secure environment without OPC material, but with SS in radiation shielding applications.

Utilization of green liquor dreg in lightweight aggregates: Effect of texture on physical properties

Green liquor dreg (GLD) is a side stream generated by pulp industry. Due to its complex physicochemical nature, it has been reported to be difficult material to utilize. Here, a novel approach towards utilization of moist and dry green liquor dreg as binder and filler in alkali-activated lightweight artificial aggregates was developed. Dried GLD and moist GLD were granulated with blast furnace slag (BFS) and Bioash in different mixtures using alkali activation. The effect of the GLD nature (dried and moist) on strength, microstructure and durability of the lightweight granules were determined and compared. Results show that the method used in homogenizing the moist GLD and other powders was efficient and improved the frost resistance. The reaction product identified in the granule’s includes calcium silicate hydrate, Mg–Al layered double hydroxides, and ettringite. These results demonstrate the potential of GLD as a binder and fillers in cementitious applications.

Optimisation of trace mineral supplementation in diets for Atlantic salmon smolt with reference to holistic fish performance in terms of growth, health, welfare, and potential environmental impacts.

The aquafeed ingredient inventory is ever changing, from marine to plant based, and recently evolving to incorporate increasing amounts of low trophic, side stream and circular economy based raw materials, each one contributing with variable amounts and qualities of macro- and micronutrients. Meeting the micronutrient requirement of farmed fish for healthy and efficient growth under normal and challenging conditions is of paramount importance. In this study we run a trial based on a 2 × 4 factorial design with three replications for each dietary treatment, where Atlantic salmon smolt were fed one of 8 experimental diets supplemented with either organic or inorganic mineral premixes (copper, iron, manganese, selenium, and zinc) at four dietary inclusion levels. We saw a trend for higher growth rate in the organic mineral groups irrespective of the dietary mineral levels. Mineral digestibility was negatively correlated with increasing mineral supplementation levels for all tested minerals but Se which increased with the increasing supplementation in the inorganic and up to the 2nd inclusion level in the organic mineral groups. Increasing mineral supplementation affected retention efficiency of Zn, Mn, Cu and Fe while mineral source affected only the retention of Se which was higher in the organic mineral groups. Moreover, fish obtained higher EPA and DHA in their body and increased slaughter yield in the organic as compared to the inorganic mineral groups and corroborated that trace mineral inclusion levels play a key role on salmon fillet's technical quality. More effects from different origin and dietary inclusion levels of trace minerals were seen on fillet yield, fillet technical and nutritional quality, bone strength, skin morphology, organ mineralization and midgut transcriptome.

Physical and Oxidative Stability of Emulsions Stabilized with Fractionated Potato Protein Hydrolysates Obtained from Starch Production Side Stream.

This work studies the emulsifying and antioxidant properties of potato protein hydrolysates (PPHs) fractions obtained through enzymatic hydrolysis of potato protein using trypsin followed by ultrafiltration. Unfractionated (PPH1) and fractionated (PPH2 as >10 kDa, PPH3 as 10-5 kDa, PPH4 as 5-0.8 kDa, and PPH5 as <0.8 kDa) protein hydrolysates were evaluated. Pendant drop tensiometry and dilatational rheology were applied for determining the ability of PPHs to reduce interfacial tension and affect the viscoelasticity of the interfacial films at the oil-water interface. Peptides >10 kDa showed the highest ability to decrease oil-water interfacial tension. All PPH fractions predominantly provided elastic, weak, and easily stretchable interfaces. PPH2 provided a more rigid interfacial layer than the other hydrolysates. Radical scavenging and metal chelating activities of PPHs were also tested and the highest activities were provided by the unfractionated hydrolysate and the fractions with peptides >5 kDa. Furthermore, the ability of PPHs to form physically and oxidatively stable 5% fish oil-in-water emulsions (pH 7) was investigated during 8-day storage at 20 °C. Our results generally show that the fractions with peptides >5 kDa provided the highest physicochemical stability, followed by the fraction with peptides between 5 and 0.8 kDa. Lastly, promising sensory results with mostly mild attributes were obtained even at protein concentration levels that are higher than needed to obtain functional properties. The more prominent attributes (e.g., bitterness and astringency) were within an acceptable range for PPH3 and PPH4.

Quinoa: Market Trend Insights In Gaining Competitive Advantage In New Product Development Toward Future Food and Nutritional Security

1. Preamble: This section provides an introduction to the quinoa chain, the problem statement, research objective, research questions, and definition of concepts. 2. Literature review: A systematic literature review was undertaken to analyze the post-harvest technology innovations in recent years. Academic databases and search engines (e.g., Scopus and Google Scholar) were utilized to find articles in English focusing on post-harvest technology, biological, and nutritional properties of quinoa, traditional uses of quinoa, product development of quinoa based products. 3. Methodology: This study bestows the features of the global quinoa trade, discovering the marketing insights into supply and demand, market access prevailing conditions and the key elements of value chain and pertinent public policy challenges to strengthen the productive sector and achieve a more efficient value chain. The present paper is based on the historical data analyzing the new market trend insights in gaining competitive advantage in new product development-wonder grain-Quinoa. 4. Results and Discussions: This study is about Quinoa, a nutritious grain which has minimal penetration in the Indian food industry. The case analyzes Quinoa in terms of its utility, market potential, and also feasibility to the Indian market. It deals with the value chain of Quinoa from the perspective of all the stakeholders involved. The case also has found out the loopholes in the value chain and provides ideas to be formulated to overcome the same. It has a study about cost cutting methods which could improve the price competitiveness of Quinoa. This review sheds light on how traditional quinoa processing and products evolved and are being adopted into novel food processing and modern food products, as well as noting the potential of side stream processing of quinoa by-products in various industrial sectors. 5. Recommendations: This research paper sheds light on how traditional quinoa processing and products evolved and are being adopted into novel food processing and modern food products, as well as noting the potential of side stream processing of quinoa by-products in various industrial sectors. Furthermore, this study moves beyond the technological aspects of quinoa production by addressing the socio-economic and environmental challenges of its production, consumption, and marketizations to reflect a holistic view of promoting the production and consumption of quinoa.

Cooling and Evaporative Crystallization of α‐D‐Galactose from a Highly Viscous Industrial Side Stream

AbstractAn industrial side stream containing mainly glucose and galactose was used to crystallize α‐D‐galactose. The dynamic viscosity of samples containing galactose and glucose solutions was measured and compared with pure glucose and galactose solutions. Various crystallization conditions were investigated in terms of temperature range and batch times in cooling crystallization and their influence on the product crystal properties. The obtained results were compared with the results of evaporative crystallization. Several characterization methods were used for studying crystal size and shape, crystal structure, and purity. The overall crystallization time of α‐D‐galactose was shortened by cooling crystallization based on stepwise temperature decrease and the desired crystal properties were achieved.

An environmentally benign, energy intensified single-column side stream extractive distillation (SC-SSED) process for Acetone/n-heptane separation

The single-column, side-stream extractive distillation (SSED) process has been proposed as a simple, novel, and energy-saving configuration for separating azeotropic mixtures, using an intermediate-boiling entrainer. However, within limited progress in separating the mixture of acetone (ACE) and n-heptane (HEP) through such processes, benzene (BEN), a human carcinogen, was frequently used as an entrainer. In view of this, our study aims to propose an environmentally benign SSED process to separate the same mixture. In the proposed process, 1-chlorobutane (CHL) is used as an entrainer. With thorough analysis, the economic performance of this process was found to outperform the other process using heavy entrainers (i.e. p-xylene and butyl propionate), while being economically comparable to the process using BEN as an entrainer. In addition, limited improvement is achieved by employing the SSED configuration for heavy entrainer-based processes, since a higher-grade steam is required at the reboiler of the extractive distillation column. Subsequently, a suitable control strategy with two temperature loops and three measurements (i.e. a side-stream temperature control loop, and a temperature difference control loop in the extractive section of the SSED column) was established. It can satisfactorily reject the specified feed disturbances (i.e. ±20% change in flowrate and composition). Compared to all other existing studies, the currently proposed control structure does not require any composition loop and, at the same time, is able to handle disturbances to a greater extent.

A Comparison between High-Performance Countercurrent Chromatography and Fast-Centrifugal Partition Chromatography for a One-Step Isolation of Flavonoids from Peanut Hulls Supported by a Conductor like Screening Model for Real Solvents.

Peanut hulls (Arachis hypogaea, Leguminosae), which are a side stream of global peanut processing, are rich in bioactive flavonoids such as luteolin, eriodictyol, and 5,7-dihydroxychromone. This study aimed to isolate these flavonoid derivatives by liquid-liquid chromatography with as few steps as possible. To this end, luteolin, eriodictyol and 5,7-dihydroxychromone were isolated from peanut hulls using two different techniques, high-performance countercurrent chromatography (HPCCC) and fast-centrifugal partition chromatography (FCPC). The suitability of the biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water (1.0/1.0/1.0/1.5; v/v/v/v) was determined by the Conductor like Screening Model for Real Solvents (COSMO-RS), which allowed the partition ratio KD-values of the three main flavonoids to be calculated. After a one-step HPCCC separation of ~1000 mg of an ethanolic peanut hull extract, 15 mg of luteolin and 8 mg of eriodictyol were isolated with purities over 96%. Furthermore, 3 mg of 5,7-dihydroxychromone could be isolated after purification by semi-preparative reversed-phase liquid chromatography (semi-prep. HPLC) in purity of over 99%. The compounds were identified by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy (NMR).

Recovery and characterization of cellulosic ethanol from fermentation of sugarcane bagasse

Industrial production of ethanol by fermentation using renewable feedstock such as sugarcane stalks has been demonstrated as a sustainable fuel chain in Brazil. This work focused on the production of cellulosic ethanol from sugarcane bagasse in a pilot scale unit by applying the current bioprocessing strategies with the aim of recovering and characterizing the end products. The feedstock was pretreated at 190 °C and a residence time of 10 min. Enzymatic hydrolysis was performed with commercial cellulolytic enzymes. Fermentation’s substrates were formulated with hydrolysate and supplemented with 8%wt sugarcane molasses. The fermentations were set up to mimic the conventional industrial fermentation in Brazil’s ethanol distilleries at high cell density with cell recycling. The fermentation resulted in a reproducible performance by the yield of 0.49 g/g, productivity of 6.96 g/(L∙h), and cell viability of 95.3%. Ethanol was recovered in a lab-scale distillation batch system. Distilled fractions showed higher content of higher alcohols and sulfur content than the standard specification of ANP (National Agency of Petroleum - Brazilian Agency) for ethanol fuel. The distillation bottom product (vinasse) presented most characteristics suitable for fertilizer or biogas applications, except for sodium and sulfate content. Therefore, for a successful technology, transference processing adjustments should be made to make the product commercially suitable and the side stream compatible for disposal as fertilizer or digestion for biogas production.

Influence of processing conditions and biochemical composition on the hydrothermal liquefaction of digested urban and agricultural wastes

Hydrothermal liquefaction (HTL) of waste biomass is a promising technology to yield an energy dense biocrude oil and a nutrient rich solid phase. An abundant and problematic biomass waste stream potentially suited for HTL is digestate, the side stream of anaerobic digestion. HTL behavior of three digestates from urban and agricultural biogas plants has been studied using response surface methodology to investigate the influence of biochemical composition, temperature, and reaction time on biocrude yield and composition, energy recovery, as well as the mobility of nutrients (N, P, K) among the product phases using KOH as catalyst. A maximum energy recovery of up to 43% and a carbon recovery of 40% were achieved for the straw/manure digestate. Mass yields and biocrude composition by GC–MS analysis are shown to be heavily influenced by feedstock composition. High yields of > 80% for the main nutrients Ca, Mg, Fe, and P to the solid residue are observed.

Exploiting Cheese Whey for Efficient Selection of Polyhydroxyalkanoates-Storing Bacteria

Agroindustrial by-products hold an enormous potential to be bioconverted into high-value-added products such as polyhydroxyalkanoates (PHA), a cost-effective alternative to conventional plastics. In this study, cheese whey, a highly abundant side stream of the cheese making process, was explored as a feasible substrate for the selection of a mixed culture highly enriched in PHA-storing bacteria using a sequencing batch reactor under an aerobic dynamic feeding regime. For that, the absence/presence of thiourea, magnesium and iron, as well as the application of two different organic loading rates (OLR), i.e., 60 and 80 CmM d−1, were tested. The results showed an improved culture selection when thiourea, magnesium and iron were added to the culture medium as well as when the highest OLR was applied. Under these conditions, the biomass achieved a maximum PHA storage of 54% and a PHA production rate of 4.81 Cmmol-PHA L−1 h−1. Additionally, the study of the microbial community showed that during this period of maximum productivity, the biomass was enriched in Azoarcus and Amaricoccus bacterial species. Conclusively, cheese whey can be considered a good feedstock to efficiently select a mixed culture with high potential to accumulate PHA and a good way to give this by-product added value.

Assessment and comparison of microcirculation and macrocirculation in horses undergoing emergency exploratory celiotomy versus elective surgical procedures.

To assess oral buccal microcirculation by hand-held videomicroscopy in horses during colic surgery, comparing microcirculation values with macrocirculatory parameters and with those of healthy elective surgical horses. Clinical prospective study. Client-owned horses (nine in the colic group; 11 in the elective group). In the colic group, buccal mucosal side stream dark-field microscopy (DFM) videos, cardiac output (CO), mean arterial pressure (MAP), and lactate were obtained at three timepoints under general anesthesia (30, 90, and 150 min after induction). Video analysis was used to determine total vessel density, proportion of perfused vessels, perfused vessel density, and heterogeneity index. Dark-field microscopy videos, MAP, and lactate were obtained at a single timepoint under general anesthesia (45 min after induction) in the elective group. There were no differences in microcirculatory parameters between colic and elective horses, nor was there a difference across timepoints in the colic group. There was a weak negative correlation between microvascular parameters and CO (rho = -0.23). The colic group did not have decreased microcirculation in comparison with the healthy elective group. Dark-field microscopy did not correlate well with macrocirculatory parameters in the colic group. Dark-field microscopy may not be a sensitive enough indicator to detect differences in microcirculation between colic and elective groups. The lack of difference in microcirculation may be due to sample size, probe location, or variation in disease severity.

Experimental evaluation of black liquor carbonation for carbon dioxide capture

Carbon dioxide is one of the main if not the most potent greenhouse gases responsible for climate change. Scientists put great efforts to tackle this problem and carbon dioxide capture seems to be a promising solution. The present study proposes a novel method of carbon dioxide capture using black liquor, a side stream from the paper and pulp industry. Its content in sodium hydroxide makes it an attractive candidate for carbon dioxide capture via carbonation. The black liquor was prepared from oat husks, a non-woody biomass, using the soda-pulping process. To estimate its carbon dioxide absorption capacity, a mixture of nitrogen and carbon dioxide (70:30%) was sparged into a bubble column reactor and computational fluid dynamics simulations of this setup were used to evaluate the mixing process. The formation of carbonate and bicarbonate ions throughout the carbonation process was followed using a Fourier-Transform Infrared (FTIR) probe and a pH meter. The absorption capacity was measured from the weight increase of the reactor. It was found to be around 30 g of carbon dioxide/L of black liquor. The carbonate and bicarbonate species in black liquor before and after carbonation were further characterized with 13C Nuclear Magnetic Resonance (NMR), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and optical microscopy. Using industrial side-streams might enable an economically feasible process without the need for production of virgin absorbents or their recovery. Furthermore, this capturing process, which is performed at atmospheric conditions might reduce the overall energy consumption. The results demonstrated that black liquor could be an attractive absorbent for carbon dioxide, paving the way for a circular and resource-efficient economy.

Dietary replacement of fishmeal with marine proteins recovered from shrimp and herring process waters promising in Atlantic salmon aquaculture

There is a general agreement that fish meal (FM) and fish oil (FO) are valuable resources for aquafeed, but that the production cannot keep the same pace as the current growth of the aquaculture industry. Therefore, there is a need to find alternative sources for lipids and protein. This study examines the possibility of using proteins recovered from seafood industry side stream waters as a complement to FM in feed for Atlantic salmon. To recover the proteins, herring and shrimp process side streams waters were flocculated then treated with dissolved air flotation (DAF), which is considered a gentle technology. Shrimp steam water was used to obtain shrimp protein (SP) and herring salt brine to obtain herring protein (HP). The recovered semi-solid protein fraction was spray dried and formulated into experimental diets at inclusion levels of 1.9–10% (dw/dw). Two feeding trials were conducted to investigate; 1) the properties of different flocculants to recover SP from shrimp steam water, alginate (Alg; 1.9% inclusion), carrageenan (Carr; 2.0% inclusion) and a synthetic flocculant from Kemira (Kem; 3.8% inclusion). 2) total or partial replacement of FM with SP-Alg (10% and no FM) and HP-Alg (3% and 8% FM). For both feeding trials each diet was provided to triplicate tanks (n = 31 and 30/tank) of Atlantic salmon with a start weight of 193 g (duration 10 weeks) and 304 g (duration 7 weeks) respectively.All fish showed similar feed intake, feed conversion ratio (on tank basis) and weight gain. The inclusion of SP or HP as total or partial replacement of FM did neither influence adiposity of the fish, as measured by condition factor, nor heposomatic index (HSI). No negative effect of the alternative protein could be found through histological examination of the intestine. In feeding trial two, diets did not affect the adaptive immune indicators CD8α and MHC II. The SP-Alg diet did not affect intestinal barrier and transporting functions, assessed using Ussing-chamber technology. However, HP-Alg affected the trans-epithelial resistance, which indicate that the intestinal barrier function could be affected by low inclusions. We conclude that from a biological perspective, SP recovered from shrimp steaming waters using Alg and DAF technology represents a new marine biomass with potential as a replacement for FM in Atlantic salmon feed. To diversify the possibility of using flocculants to retrieve proteins we also suggest further investigation of the potential to use Carr in larger inclusions.

Bioprocess optimization for lactic and succinic acid production from a pulp and paper industry side stream.

The effective and cheap production of platform chemicals is a crucial step towards the transition to a bio-based economy. In this work, biotechnological methods using sustainable, cheap, and readily available raw materials bring bio-economy and industrial microbiology together: Microbial production of two platform chemicals is demonstrated [lactic (LA) and succinic acid (SA)] from a non-expensive side stream of pulp and paper industry (fibre sludge) proposing a sustainable way to valorize it towards economically important monomers for bioplastics formation. This work showed a promising new route for their microbial production which can pave the way for new market expectations within the circular economy principles. Fibre sludge was enzymatically hydrolysed for 72h to generate a glucose rich hydrolysate (100g·L-1 glucose content) to serve as fermentation medium for Bacillus coagulans A 541, A162 strains and Actinobacillus succinogenis B1, as well as Basfia succiniciproducens B2. All microorganisms were investigated in batch fermentations, showing the ability to produce either lactic or succinic acid, respectively. The highest yield and productivities for lactic production were 0.99g·g-1 and 3.75g·L-1·h-1 whereas the succinic acid production stabilized at 0.77g·g-1 and 1.16g·L-1·h-1.