Recovery Of Bioproducts Research Articles

Review of recent advances in utilising aquaculture wastewater for algae cultivation and microalgae-based bioproduct recovery

Review of recent advances in utilising aquaculture wastewater for algae cultivation and microalgae-based bioproduct recovery

Light Intensity Effects on Bioproduct Recovery from Fuel Wastewater Using Purple Phototrophic Bacteria in a Hybrid Biofilm-Suspended Growth System.

This research looked at how three different light intensities (1600, 4300, and 7200 lx) affect the biomass development, treatment of fuel synthesis wastewater and the recovery of valuable bioproducts between biofilm and suspended growth in a purple-bacteria enriched photobioreactor. Each condition was run in duplicate using an agricultural shade cloth as the biofilm support media in a continuously mixed batch reactor. The results showed that the highest chemical oxygen demand (COD) removal rate (56.8 ± 0.9%) was found under the highest light intensity (7200 lx), which also led to the most biofilm formation and highest biofilm biomass production (1225 ± 95.7 mg). The maximum carotenoids (Crts) and bacteriochlorophylls (BChls) content occurred in the suspended growth of the 7200 lx reactor. BChls decreased with light intensity in suspended growth, while in biofilm both Crts and BChls were relatively stable between light conditions, likely due to an averaging effect as biofilm thickened at higher light intensity. Light intensity did not affect protein content of the biomass, however, biofilm showed a lower average (41.2% to 43.7%) than suspended biomass (45.4% to 47.7%). For polyhydroxybutyrate (PHB) the highest cell concentration in biofilm occurred at 1600 lx (11.4 ± 2.4%), while for suspended growth it occurred at 7200 lx (22.7 ± 0.3%), though total PHB productivity remained similar between reactors. Shading effects from the externally located biofilm could explain most variations in bioproduct distribution. Overall, these findings suggest that controlling light intensity can effectively influence the treatment of fuel synthesis wastewater and the recovery of valuable bioproducts in a biofilm photobioreactor.

Sustainable biorefining: Hydrothermal liquefaction of diatom biomass for bio-crude and nano-biosilica recovery

Diatom, a unique species of microalgae is a highly promising resource for the production of valuable bio-crude and silica nanomaterial. However, the complex nature of diatom cell structure presents significant downstream processing challenges and leads to inefficient bio-product recovery. To overcome this challenge, this study aimed to develop a one-step approach for the valorization of Denticula sp. dominated diatom consortium using hydrothermal liquefaction (HTL) process with the recovery of three major products. The first output, referred to as biocrude, constituted 22% of the total yield, consisting of 9.5% unbound bio-crude and 12.5% cell wall-bound organic fraction. The bio-crude consisted primarily of oxidized and desirable organic compounds like alcohols (24.4%), long-chain saturated hydrocarbons (23.6%), and esters (17.6%), with only a few undesirable nitrogen-containing compounds (18.9%). The second resultant product comprised nanoporous bio-silica structures, yielding 56%. These silica structures exhibited enhanced quality in comparison to the conventional thermal extraction technique employed for their retrieval and were found to be three-dimensional, highly porous, intact silica structures with low trace elements and a high surface area (53.7 m2 g−1). The third acquired product, the aqueous fraction, was observed to possess elevated levels of nitrate-nitrogen (440 mg L−1) and total dissolved phosphate (975 mg L−1). Overall, the study highlights the potential of HTL as an efficient diatom downstream processing method that allows for the complete valorization of intermediates, resulting in a sustainable biomass conversion and product recovery technology.

An Explainable Classification Framework for Determining and Understanding the Suitability of Solvent Extraction for Bioproduct Recovery

An Explainable Classification Framework for Determining and Understanding the Suitability of Solvent Extraction for Bioproduct Recovery

Supercritical CO2 Extraction of Wine and Beer Yeast Residues for Sustainable Bioproduct Recovery

Abstract This paper presents a study on the use of supercritical carbon dioxide (SC-CO2) extraction to isolate yeast metabolites from beer and wine matrices effectively. A major contributor to the flavour and aroma profiles of alcoholic beverages, yeast contains a rich reservoir of bioactive compounds that can be used in various industries, including food and pharmaceuticals. Conventional extraction methods often fail to obtain comprehensive and high-quality recoveries of these valuable metabolites. In response, this study explores the use of SC-CO2, a green and tuneable solvent, to overcome the limitations of conventional extraction methods. The study investigates the influence of critical process parameters such as pressure, temperature, and extraction time on the yield and composition of extracted yeast metabolites. Advanced analytical methods (gas chromatography for the determination of fatty acids and high-performance liquid chromatography for the determination of the amino acid composition of the yeast residue left after extraction) are used in the analysis to characterize the chemical profile of the extracts. The results show that SC-CO2 extraction offers a promising alternative to extract a diverse range of yeast-derived compounds, including flavour-enhancing esters, phenolic compounds, and bioactive peptides. The optimized extraction conditions show a significant improvement in extraction efficiency compared to traditional methods. Sensory analysis reveals that beverages produced with SCCO2-extracted yeast have distinctive and desirable flavour profiles. This research not only contributes to the development of extraction technologies in the beverage industry but also opens up new opportunities for the use of yeast-derived bioactive compounds in various applications. The environmentally friendly nature of SC-CO2 extraction meets the growing demand for sustainable and clean technologies in food and beverage processing. Overall, the results of this study highlight the potential of SC-CO2 extraction as a valuable tool for improving the extraction of bioactive yeast metabolites, thereby influencing the quality and sensory properties of beer and wine.

Production of extracellular agarase from Priestia megaterium AT7 and evaluation on marine algae hydrolysis

Agar is a common component biosynthesized from various marine algae species that is widely applied in various fields including food and pharmaceutical industries. However, the structural composition of agar is highly resisted against chemical and biological hydrolysis. Therefore, tremendous research is exploring various pretreatment strategies to break down the intrinsic chemical structural of agar linkage (i.e. neutral agarose and highly sulfated agaropectin) prior for its industrial potential usage. In this research work, a novel agar degrading bacterium was screened and isolated from agriculture soils. Molecular identification using nucleotide sequence of 16 s rRNA region comparison has indicated that the isolate belonged to Priestia genus, and was identified as Priestia megaterium AT7. The maximum enzyme activity was 52.85 ± 1.76 U/mL after 96 h of culture with 5% inoculum size and agitation speed of 180 rpm. Results indicated that the optimal condition for the production of agarose was achieved at pH 7 at 50 °C. The effects of metal ions (e.g. Ca2+, Co2+, Cu2+, Mn2+, Mg2+, Zn2+ and Fe2+) and organic solvents (e.g. acetone, ethanol, methanol, hexane and isopropanol) on enzyme activity were also evaluated. Marine algae hydrolysis evaluation at concentration of 0.1% indicated the enzyme produced reducing sugar of 683.94 ± 26.93 µg/g after 24 h of treatment. It was also found that the highest antioxidant activities obtained after 20 h of treatment was able to achieve 81.76 ± 3.90% at marine algae concentration of 0.1%. The findings obtained from this research work shows the promising application of extracellular agarase to saccharify marine algae for the recovery of value-added bioproducts.

A fluidized-bed-riser adsorption system for continuous bioproduct recovery from crude feedstock.

In this work, a novel technique for continuous purification of biologics from a crude feedstock is demonstrated with equipment referred to as Fluidized Bed Adsorption System (FBRAS). The development and validation of such unit operations were performed utilizing lysozyme as a model protein and Relisorb™ SP405/EB as a carrier. The performance of FBRAS to carry out combined clarification and purification was evaluated by capturing of antifungal peptides directly from the lysed broth. The novel technique reduced the number of process unit operations from six to three without having an impact on purity. Overall productivity increased by 250% in comparison to the existing downstream processing routine.

Moving adsorption belt system for continuous bioproduct recovery utilizing composite fibrous adsorbents.

A continuous protein recovery and purification system based on the true moving bed concept is presented. A novel adsorbent material, in the form of an elastic and robust woven fabric, served as a moving belt following the general designs observed in known belt conveyors. The composite fibrous material that forms the said woven fabric showed high protein binding capacity, reaching a static binding capacity equal to 107.3mg/g, as determined via isotherm experiments. Moreover, testing the same cation exchange fibrous material in a packed bed format resulted in excellent dynamic binding capacity values (54.5mg/g) even when operating at high flow rates (480cm/h). In a subsequent step, a benchtop prototype was designed, constructed, and tested. Results indicated that the moving belt system could recover a model protein (hen egg white lysozyme) with a productivity up to 0.5mg/cm2/h. Likewise, a monoclonal antibody was directly recovered from unclarified CHO_K1 cell line culture with high purity, as judged by SDS-PAGE, high purification factor (5.8), and in a single step, confirming the suitability and selectivity of the purification procedure.

Implementation and Optimization of Algal Biomass in Value-Added Products Recovery: A Step towards Algae-Based Green Economy

Algal biomass is a prospective feedstock for the eco-sustainable production of many different products with added value, such as meals, feeds, and fuels. The remaining biomass from the algae can be used as raw material and can be transformed into useful secondary products after the important macromolecules have been removed. By optimizing algal biomass hydrolysate utilizing microbial fermentation, several studies demonstrated the generation of bioenergy (bioalcohol, biogas, and biohydrogen) and biochemicals (organic acids and biopolymers). Since the harvest and maintenance of sustainable algal cultivation incur considerable energy and economical prowess, developing products from algae remains a challenge to be countered in commercial applications. This is a typical bottleneck issue when processing algae for fuels or chemicals at the pilot scale. Implementation of integrated algae biorefinery methods can substantially reduce the cost of production and energy consumption. An algae-based green economy can be financially more viable and utilizable, especially for countries with weaker economies. This review’s goal is to examine the implementation of integrated biorefineries for the recovery of bioproducts generated from algae and potential applications. In this context, the life cycle analysis and business elements of a unified algal biorefinery are also addressed.

A review on regeneration of biowaste into bio-products and bioenergy: Life cycle assessment and circular economy

Waste generation has become common in all sectors involving ecological pollution and requires immediate solution. Current approach towards waste has been changed as technology has improved in converting waste into valuable resources. Due to its beneficial conversion into various bioproducts and energy, biomass availability has a significant impact on the circular economy. Nutrient and product recovery from biowaste needs more energy-intensive stages for efficient valorization. The ability of developed approaches to transform complex, natural biomass into value added products and energy form with circular bioeconomy has been elaborated in this review. The utilization of biomass or feedstock in industries for obtaining products such as biofuels, bio-oil, fertilizers and other energy forms has been demonstrated. The product recovery methods utilized for conversion of various biomasses is explained in detail. Anaerobic digestion, hydrothermal, and thermochemical processes have been emphasized on this review for the bioproduct recovery from biowaste. Lifecycle analysis of different biowaste conversion process revealed the better social and environmental sustainability of the process. This article also expands with biowaste circular economy for producing bioproducts and bioenergy as well as resolving biorefinery protocols that can be utilized in industrial levels for maintaining appropriate financial portrait for biofuels and other bioenergy products.

Hydrothermal pretreatment based on semi-continuous flow-through sequential reactors for the recovery of bioproducts from jabuticaba (Myrciaria cauliflora) peel

This study evaluated a novel pretreatment process composed of two sequential flow-through hydrothermal reactors operated in a semi-continuous mode to recover value-added bioproducts from jabuticaba (Myrciaria cauliflora) peel. The system was operated at 15 MPa, 5 mL min−1, feed of 10 g jabuticaba peel per reactor, 45 min of process duration, and temperature ranging from 60° to 210°C using the design of experiment (DOE) followed by response surface methodology (RSM). The results showed that the two sequential reactors at 135 °C following by 60 °C increased the monosaccharides (160.74 mg g−1), the extraction of cyanidin-3-glucoside (0.78 mg g−1) and the total phenolic compounds yields (0.58 mg g−1). The formation of inhibitors was more present in the two sequential reactors at 210 °C. The hydrothermal pretreatment designed demonstrated to be an eco-friendly technology for the recovery of value-added products from jabuticaba peel.

A novel approach for microalgal cell disruption and bioproducts extraction using non-thermal atmospheric plasma (NTAP) technology and chitosan flocculation

Microalgal cell disruption and bio-product extraction still remain as major challenging steps for biomass downstream processing. In this study, a sustainable approach of using non-thermal atmospheric plasma (NTAP) and chitosan flocculation was developed for microalgal cell disruption and bio-product recovery from wet C. Sorokiniana. For this purpose, the performance of NTAP treatment for cell disruption and extraction of protein, carbohydrate and lipid was investigated by using different applied voltages (8–16 kV). Then, the application of chitosan on recovery of bioproducts from the culture medium was evaluated. Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) images were used to analyze the flocculation mechanism and for flocs characterization. Additionally, the energy consumption and efficiency of the NTAP process were analyzed. According to the NTAP results, the highest cell disruption of 75% was achieved under the applied voltage of 16 kV. However, in the case of bioproducts extraction, the optimal applied voltage was 12 kV which was able to yield 41, 24 and 36 (%CDW) of protein, carbohydrate and lipid, respectively. Adding 100 mg/L chitosan efficiently recovered the released protein (65%) and carbohydrate (85%) from culture medium, while the highest lipid recovery (60%) was achieved at 150 mg/L chitosan addition. This study proved that the utilization of NTAP and chitosan treatment can be considered as a promising approach for valuable products extraction from microalgae.

Life cycle assessment of microalgae systems for wastewater treatment and bioproducts recovery: Natural pigments, biofertilizer and biogas

The aim of this study was to assess the potential environmental impacts associated with microalgae systems for wastewater treatment and bioproducts recovery. In this sense, a Life Cycle Assessment was carried out evaluating two systems treating i) urban wastewater and ii) industrial wastewater (from a food industry), with the recovery of bioproducts (i.e. natural pigments and biofertilizer) and bioenergy (i.e. biogas). Additionally, both alternatives were compared to iii) a conventional system using a standard growth medium for microalgae cultivation in order to show the potential benefits of using wastewater compared to typical cultivation approaches. The results indicated that the system treating industrial wastewater with unialgal culture had lower environmental impacts than the system treating urban wastewater with mixed cultures. Bioproducts recovery from microalgae wastewater treatment systems can reduce the environmental impacts up to 5 times compared to a conventional system using a standard growth medium. This was mainly due to the lower chemicals consumption for microalgae cultivation. Food-industry effluent showed to be the most promising scenario for bioproducts recovery from microalgae treating wastewater, because of its better quality compared to urban wastewater which also allows the cultivation of a single microalgae species. In conclusion, microalgae wastewater treatment systems are a promising solution not only for wastewater treatment but also to boost the circular bioeconomy in the water sector through microalgae-based product recovery.

Semi-continuous flow-through hydrothermal pretreatment for the recovery of bioproducts from jabuticaba (Myrciaria cauliflora) agro-industrial by-product

The valorization of the by-product of the agro-industrial processing of jabuticaba (Myrciaria cauliflora) was studied by hydrothermal pretreatment. Experiments were carried out in a semi-continuous flow-through process for 45 min, at 15 MPa, a water flow rate of 5 mL min−1, and at different temperatures (60 – 210 °C). The results demonstrate that fructose and glucose were the sugars with the highest concentration in all analyzed treatments. Arabinose and cellobiose were obtained only at higher temperatures (above 130 °C), demonstrating that they were released from the hydrolysis of polysaccharides. The highest cyanidin-3-glucoside yield (1.88 mg g−1) was achieved at 60 °C. The treatments at 135 and 210 °C promoted the degradation of cyanidin-3-glucoside, leading to yields lower than 0.05 mg g−1. At 60 °C, it was possible to recover 74.18 mg g−1 of glucose, 103.77 mg g−1 of fructose, 30.75 mg g−1 of citric acid, and 1.88 mg g−1 of cyanidin-3-glucoside, without the presence of furfural and 5-hydroxymethylfurfural. The results suggest that hydrothermal pretreatment is a promising eco-friendly technology to recover sugars, organic acids, and anthocyanins from jabuticaba by-products in a circular economy framework.

Megaporous monolithic adsorbents for bioproduct recovery as prepared on the basis of nonwoven fabrics.

Megaporous adsorbents were prepared based on nonwoven polyethylene terephthalate (PET) fabrics and functionalized by covalent modification with polyvinylamine (PVAm) or monotriazinyl-β-cyclodextrin-substituted polyvinylamine (PVAm-MCT-β-CD). Mechanical properties of the resulting fabrics were maintained, as judged by tensile strength tests and scanning electron microscopy. Exceptional porosity (≥82%) and preserved hydrodynamic characteristics (Pe≥63) indicated excellent structural stability when packed. The performance of the constructed adsorbents was evaluated with high molecular weight (proteins) and low molecular weight (dyes) model compounds. The static binding capacity (SBC) for bovine serum albumin (BSA) was 79.7±1.3 and 92.9±8.2mg/g for PVAm-modified and PVAm-MCT-β-CD-modified fabrics, respectively. The mentioned materials also adsorbed Orange II, an acidic dye (92.4±2.6 and 101.9±2.6mg/g, respectively), indicating that the hydrophobicity was a prevailing binding mechanism operating at a pH close to isoelectric point. SBC for lysozyme and toluidine blue O (TBO, a basic dye) onto PVAm-MCT-β-CD functionalized PET was 52.7±5.1 and 73.3±0.6mg/g, respectively. TBOs have also shown some affinity for PVAm functionalized PET, but this was most likely to be mediated by hydrophobicity. On the other hand, operating at a superficial velocity of 90cm/h, dynamic binding capacity for BSA was 11.4±3.5 and 2.5±0.6mg/g indicating the importance of possible aggregation mechanisms during protein binding at equilibrium. Thus, PET-based adsorbents require further functional improvement for chromatography applications. However, the easy-to-construct, scalable nonwoven adsorbents deserve further attention as a potential alternative to packed-bed-chromatography adsorbents.

Recent biotechnological developments in reshaping the microalgal genome: A signal for green recovery in biorefinery practices

The use of renewable energy sources as a substitute for nonrenewable fossil fuels is urgently required. Algae biorefinery platform provides an excellent alternate to overcome future energy problems. However, to let this viable biomass be competent with existing feedstocks, it is necessary to exploit genetic manipulation and improvement in upstream and downstream platforms for optimal bio-product recovery. Furthermore, the techno-economic strategies further maximize metabolites production for biofuel, biohydrogen, and other industrial applications. The experimental methodologies in algal photobioreactor promote high biomass production, enriched in lipid and starch content in limited environmental conditions. This review presents an optimization framework combining genetic manipulation methods to simulate microalgal growth dynamics, understand the complexity of algal biorefinery to scale up, and identify green strategies for techno-economic feasibility of algae for biomass conversion. Overall, the algal biorefinery opens up new possibilities for the valorization of algae biomass and the synthesis of various novel products.

Formation and stability of oil-in-water emulsions based on components of bioprocesses: A microfluidic analysis

Undesirable oil-in-water (O/W) emulsions are typically developed and stabilized during biotechnological processes, hampering the recovery of oil-based bioproducts. Such emulsions emerge in the fermentation medium due not only to the process conditions, but mainly to the broth composition. In this light, an in-depth study of the formation and stability of these colloidal systems is paramount to establish an appropriate formulation, especially considering some highly relevant components for bioprocesses (such as antifoams). In general, antifoams are added to the fermentation broth with little control, although they can potentially lead to the formation of undesirable emulsions. In this context, we analyzed O/W emulsions stabilized by yeast cells and two widely used antifoaming agents (Pluronic L81 and Antifoam C) within microfluidic glass capillaries to perform a high-throughput analysis and reveal the role of these components in the formation of stable emulsions. In general, both antifoams and yeast cells enabled the formation of droplets depending on the characteristics of the oily phase, but marked differences were observed in the stability of the formed emulsions. For instance, Pluronic L81 allowed the formation of a highly stable emulsion, while Antifoam C produced droplets more susceptible to destabilization. Such results indicate that a particular choice of the pair antifoam-oily phase can facilitate the destabilization process and even impair the mechanism of droplet formation.

Multi-product biorefinery from Arthrospira platensis biomass as feedstock for bioethanol and lactic acid production

With the aim to reach the maximum recovery of bulk and specialty bioproducts while minimizing waste generation, a multi-product biorefinery for ethanol and lactic acid production from the biomass of cyanobacterium Arthrospira platensis was investigated. Therefore, the residual biomass resulting from different pretreatments consisting of supercritical fluid extraction (SF) and microwave assisted extraction with non-polar (MN) and polar solvents (MP), previously applied on A. platensis to extract bioactive metabolites, was further valorized. In particular, it was used as a substrate for fermentation with Saccharomyces cerevisiae LPB-287 and Lactobacillus acidophilus ATCC 43121 to produce bioethanol (BE) and lactic acid (LA), respectively. The maximum concentrations achieved were 3.02 ± 0.07 g/L of BE by the MN process at 120 rpm 30 °C, and 9.67 ± 0.05 g/L of LA by the SF process at 120 rpm 37 °C. An economic analysis of BE and LA production was carried out to elucidate the impact of fermentation scale, fermenter costs, production titer, fermentation time and cyanobacterial biomass production cost. The results indicated that the critical variables are fermenter scale, equipment cost, and product titer; time process was analyzed but was not critical. As scale increased, costs tended to stabilize, but also more product was generated, which causes production costs per unit of product to sharply decrease. The median value of production cost was US$ 1.27 and US$ 0.39, for BE and LA, respectively, supporting the concept of cyanobacterium biomass being used for fermentation and subsequent extraction to obtain ethanol and lactic acid as end products from A. platensis.

Advances, current challenges, and future trends in bioseparation: perspective analysis of the papers published in JCTB

AbstractBioseparation is a crucial process for the obtention of biological products that are essential in daily life, such as medicine and food. At first, the researchers centered their efforts on the optimization of the upstream processes, conducting to high product titer. Afterwards, they turned their attention to improving the downstream processes. Since then, a revolution of technologies has been reported for the recovery, separation, and/or purification of bioproducts. Therefore, this perspective article aims to present the advances, current challenges, and future trends in bioseparation. In this context, a practical approach to summarize the published articles in the Journal of Chemical Technology and Biotechnology regarding this topic is presented; in addition, a classification of, (i) trusted old, (ii) novel, and (iii) evolved technologies is proposed. © 2021 Society of Chemical Industry (SCI).

Challenges and opportunities for more efficient water use and circular wastewater management. The case of Campania Region, Italy

By 2050, global demand for water is expected to increase by some 55% due to population growth and urbanization. The utilization of large amounts of freshwater in the world, generate huge volumes of wastewater of which, globally, more than 80% is discharged without treatment, thus causing impacts on aquatic ecosystems, human health and economic productivity. More sustainable practices of wastewater management are expected as a way towards circular bioeconomy (CBE) processes, whose goal is to implement closed systems promoting the systematic use of recycling, reuse and recovery of bioproducts and by-products and the reduction of waste generation. This approach, if adopted in the water and wastewater sector, can ensure environmental, economic and social benefits. The reuse of wastewater, on the one hand, reduces the volume of wastewater and the pressure on water bodies; on the other hand, the recovery of nutrients (P or N) and/or other high value bioproducts (biogas, cellulose, biopolymers) from wastewater offers numerous advantages in terms of supplying new raw bio-based materials that can be refed back to supply chains (thus substituting fossil resources) and, at the same time, producing cleaner water to be reused. Nevertheless, while in Europe many industries have demonstrated the ability to recycle and reuse water, in many regions of Italy the sustainable management of water and wastewater is not yet consolidated. In this study we explore the available technological, economic and environmental options concerning water use and wastewater treatment and we apply them to design appropriate scenarios for improved use efficiency and circular management. A comprehensive literature review of the most promising wastewater treatment processes for resources and energy valorization was conducted. The recovery of PHAs, struvite, nitrogen and algal biomass, as potential substitutes for conventional PET, phosphate and nitrogen chemical fertilizers and electricity, respectively, in addition to reusable treated water, were hypothesized and carefully discussed. Resulting scenarios are tested against the present situation of Campania Region (situated in Southern Italy) based on population and demand statistics, in order to develop strategies and policies potentially applicable locally and elsewhere.