Co-cultivation Systems Research Articles

Evaluation of the Plant Growth Promoting Effect of Root Contact, Diffusible and Volatile Compounds Produced by Rhizobacteria and Microalgae on Arabidopsis Thaliana

Bacteria and microalgae have beneficial impact on plant growth and survival through host functional and adaptive traits via complex mechanisms. Volatile and non-volatile metabolites produced by microorganisms have a continuous effect on plants by providing nutrients and regulating various plant metabolic and signaling pathways. The aim of this study was to assess the plant promoting effect of two Chlorella spp. microalgae under mixotrophic conditions, as well as the effects of plant growth promoting rhizobacteria (PGPR) Bacillus sp. WCC-B36, Azospirillum sp. WCC-ASP12 and Azotobacter sp. WCC-IZA56 on the model plant Arabidopsis thaliana. Growth and quality parameters were followed in three different co-cultivation systems as (i) direct root contact supplemented with density effect, (ii) contact with diffusible compounds and (iii) effects of volatile compounds. Direct effect mediated by rhizobacteria promoted significant shoot and root length growth with well-developed root architecture at low bacterial densities (<105 CFU – colony forming unit mL−1), which became more pronounced over time. At a higher microbial density (>107 CFU mL−1), plant growth was retarded regardless of the bacteria present. This suggests that the microenvironment surrounding the colonies was altered and there was competition for nutrients. Our results indicate that the metabolites, diffusible and volatile organic substances produced by the microalgae enhanced lateral root growth and root hair formation, while inhibited primary root elongation. Volatile and diffusible substances of Chlorella sp. CHL13 and Bacillus sp. WCC-B36 have the most significant effect on seedlings and primary root growth.

Potential of house crickets Acheta domesticus L. (Orthoptera: Gryllidae) as a novel food source for integration in a co-cultivation system

Environmental controlled indoor cultivation combined with a co-cultivation of different organisms can address the challenges of agri-food systems and lead towards resilience. Due to their numerous food and feed applications and low environmental impact, house crickets (Achaeta domesticus) are a promising candidate for indoor cultivation systems. The present study explored the potential of house crickets for application in indoor farming and co-cultivation systems, by applying PAR at elevated intensity combined with narrowband UV-B irradiation at 285 nm and observing its effect on the development of the house crickets, their nutritional composition and the mineral content of their frass, which has potential as fertilizer. Narrowband UV-B irradiation increased the survival rate of the house crickets by >20%, while not affecting their weight (g/cricket), compared to house crickets reared in the same conditions without the narrowband UV-B irradiation (Elevated PAR). Furthermore, narrowband UV-B irradiation increased by 16.18% and 67.95% the protein and chitin content, respectively, compared to the house crickets reared in the same conditions without UV-B irradiation. Finally, all the frass samples showed a rich mineral profile containing Ca, K, Mg, Na and S, with narrowband UV-B irradiation affecting its composition throughout the rearing process. Thus, this study demonstrates that house crickets can adapt physiologically to different environments and are suitable for integration into indoor farming and co-cultivation systems. Thus, it is suggested that house crickets, as edible insects, have significant potential to be cultivated with other organisms, an important step for the circular economy.

Exploring The Potential of Microalgae-Fungi Co-Cultivation for Sustainable Bioprocessing in Microalgae Biorefinery

Developing co-cultivation systems involving microalgae and fungi has shown promising potential for microalgae harvesting technology. As discussed in this review, the co-cultivation of microalgae and fungi has emerged as a novel approach for enhancing biomass and lipid production, wastewater treatment, biofuel production, and high-value products. However, despite being used for a few years, this technique is still in its early stages of development and has yet to be widely applied in the industry. The main challenges associated with co-cultivation include designing effective cultivation systems, managing nutrient requirements, selecting compatible strains, and implementing contamination control measures. In this study, bibliometric analysis was conducted (using the Web of Science database) to examine global trends and developments in microalgae-fungi co-cultivation research between 2014 and 2023, which aimed to identify the research progression, prominent contributors, and leading countries in the research field. The dataset comprised 682 articles, 242 reviews, 31 book chapters, and 22 conference papers. The results showed a rapid increment of publications with China as an active nation in this research area, followed by India, the USA, Italy, Spain, etc. As demonstrated in this study, the immense potential of co-cultivation techniques suggests further exploration, particularly in employing different microalgae species with exceptional characteristics in conjunction with non-pathogenic and edible fungi for profitable industrialization.

Construction of an efficient microalgal-fungal co-cultivation system for swine wastewater treatment: Nutrients removal and extracellular polymeric substances (EPS)-mediated aggregated structure formation

Microalgal-fungal co-cultivation technology has demonstrated outstanding efficacy in wastewater treatment and valuable resources recovery. However, it is still unclear how extracellular polymeric substances (EPS) could potentially affect the formation and development of co-cultivation aggregates. In this work, efficient microalgal-fungal co-cultivation systems (MFCS) were developed for swine wastewater treatment. Different co-cultivation systems were established using various microalgae (Chlorella sorokiniana and Scenedesmus dimorphus) with fungi (Aspergillus oryzae or Aspergillus niger). The results showed that the introduction of fungi improved nutrient removal, and C. sorokiniana-A. oryzae co-cultivation system demonstrated the highest removal efficiency for chemical oxygen demand (COD) (85.9 %), ammonium (NH4+-N) (76.5 %), and total phosphorus (TP) (60.3 %). Biomass production in co-cultivation system was higher, and S. dimorphus-A. oryzae co-cultivation system achieved the highest biomass production of 0.74 g/L. In addition, the lipid content in co-cultivation system was up to 33.3 %, which was 1.8 times higher than that in the mono-cultivation group. Besides biomass production, A. oryzae also promoted the photosynthetic activity of C. sorokiniana, showing higher pigments content and electron transport efficiency. The morphology of co-cultivation systems displayed complex interactions between fungi and microalgae, forming aggregated structures. The analysis of EPS demonstrated their importance in the formation and stabilization of microalgae-fungal aggregates. Moreover, proteins and polysaccharides, along with chemical bonds (N-H, C = O and C-O-C), played a crucial role in the formation and development of aggregates. This study provides insights into the potential of MFCS for swine wastewater treatment, highlighting the importance of species selection and EPS-mediated interactions in enhancing system performance.

Microalgal co-cultivation -recent methods, trends in omic-studies, applications, and future challenges.

The burgeoning human population has resulted in an augmented demand for raw materials and energy sources, which in turn has led to a deleterious environmental impact marked by elevated greenhouse gas (GHG) emissions, acidification of water bodies, and escalating global temperatures. Therefore, it is imperative that modern society develop sustainable technologies to avert future environmental degradation and generate alternative bioproduct-producing technologies. A promising approach to tackling this challenge involves utilizing natural microbial consortia or designing synthetic communities of microorganisms as a foundation to develop diverse and sustainable applications for bioproduct production, wastewater treatment, GHG emission reduction, energy crisis alleviation, and soil fertility enhancement. Microalgae, which are photosynthetic microorganisms that inhabit aquatic environments and exhibit a high capacity for CO2 fixation, are particularly appealing in this context. They can convert light energy and atmospheric CO2 or industrial flue gases into valuable biomass and organic chemicals, thereby contributing to GHG emission reduction. To date, most microalgae cultivation studies have focused on monoculture systems. However, maintaining a microalgae monoculture system can be challenging due to contamination by other microorganisms (e.g., yeasts, fungi, bacteria, and other microalgae species), which can lead to low productivity, culture collapse, and low-quality biomass. Co-culture systems, which produce robust microorganism consortia or communities, present a compelling strategy for addressing contamination problems. In recent years, research and development of innovative co-cultivation techniques have substantially increased. Nevertheless, many microalgae co-culturing technologies remain in the developmental phase and have yet to be scaled and commercialized. Accordingly, this review presents a thorough literature review of research conducted in the last few decades, exploring the advantages and disadvantages of microalgae co-cultivation systems that involve microalgae-bacteria, microalgae-fungi, and microalgae-microalgae/algae systems. The manuscript also addresses diverse uses of co-culture systems, and growing methods, and includes one of the most exciting research areas in co-culturing systems, which are omic studies that elucidate different interaction mechanisms among microbial communities. Finally, the manuscript discusses the economic viability, future challenges, and prospects of microalgal co-cultivation methods.

Biofuel Production Using Cultivated Algae: Technologies, Economics, and Its Environmental Impacts

The process of looking for alternative energy sources is driven by the increasing demand for energy and environmental contamination caused by using fossil fuels. Recent investigations reported the efficiency of microalgae for biofuel production due to its low cost of production, high speed of growth, and ability to grow in harsh environments. In addition, many microalgae are photosynthetic, consuming CO2 and solar light to grow in biomass and providing a promising bioenergy source. This review presents the recent advances in the application of microalgae for biofuel production. In addition, cultivation and harvesting systems and environmental factors that affect microalgae cultivation for biofuel production have also been discussed. Moreover, lipid extraction and conversion technologies to biofuel are presented. The mixotrophic cultivation strategy is promising as it combines the advantages of heterotrophy and autotrophy. Green harvesting methods such as using bio-coagulants and flocculants are promising technologies to reduce the cost of microalgal biomass production. In the future, more investigations into co-cultivation systems, new green harvesting methods, high lipids extraction methods, and the optimization of lipid extraction and converting processes should be implemented to increase the sustainability of microalgae application for biofuel production.

The effects of influent chemical oxygen demand and strigolactone analog concentration on integral biogas upgrading and pollutants removal from piggery wastewater by different microalgae-based technologies

Microalgae-based technologies are promising strategies for efficient wastewater treatment and biogas upgrading. In this study, three types of microalga-fungi/bacteria symbiotic systems stimulated with the strigolactone analog (GR24) were used to simultaneously remove nutrients from treated piggery wastewater and CO2 from biogas. The effects of initial concentrations of chemical oxygen demand (COD) and GR24 on nutrient removal and biogas upgrading were investigated. When the initial COD concentration was 1200 mg/L, the Chlorella vulgaris–Ganoderma lucidum–endophytic bacteria co-cultivation systems achieved the best photosynthetic performance and microalgae growth. Moreover, under the appropriate COD concentration (1200 mg/L), the highest nutrient/CO2 removal efficiencies were obtained. In addition, 10−9 M GR24 significantly accelerated nutrient/CO2 removal efficiencies. These findings provide a theoretical basis for scale-up experiments using microalgae-based technologies

Effect of Narrowband UV-B Irradiation on the Growth Performance of House Crickets.

Indoor co-cultivation systems can answer to the need for sustainable and resilient food production systems. Rearing organisms under light-emitting diodes (LEDs) irradiation provides the possibility to control and shape the emitted light spectra. UV-B-irradiation (280-315 nm) can positively affect the nutritional composition of different plants and other organisms, whereas information on edible insects is scarce. To evaluate the potential effect of the photosynthetically active radiation (PAR) and LED-emitting LEDs on the rearing and nutritional quality of edible insects, house crickets (Acheta domesticus) were reared from the age of 21 days under controlled LED spectra, with an additional UV-B (0.08 W/m2) dose of 1.15 KJm2 d-1 (illuminated over a period for 4 h per day) for 34 days. UV-B exposure showed no harm to the weight of the crickets and significantly increased their survival by ca. 10% under narrowband UV-B treatment. The nutritional composition including proteins, fat and chitin contents of the insects was not affected by the UV-B light and reached values of 60.03 ± 10.41, 22.38 ± 2.12 and 9.33 ± 1.21%, respectively, under the LED irradiation. Therefore, house crickets can grow under LED irradiation with a positive effect of narrowband UV-B application on their survival.

Novel cost-efficient protein-based membrane system for cells cocultivation and modeling the intercellular communication.

In vitro systems serve as compact and manipulate models to investigate interactions between different cell types. A homogeneous population of cells predictably and uniformly responds to external factors. In a heterogeneous cell population, the effect of external growth factors is perceived in the context of intercellular interactions. Indirect cell cocultivation allows one to observe the paracrine effects of cells and separately analyze cell populations. The article describes an application of custom-made cell cocultivation systems based on protein membranes separated from the bottom of the vessel by the 3D printed holder or kept afloat by a magnetic field. Using the proposed cocultivation system, we analyzed the interaction of A549 cells and fibroblasts, in the presence and absence of growth factors. During cocultivation of cells, the expression of genes of the activation for epithelial and mesenchymal transitions decreases. The article proposes the application of a newly available system for the cocultivation of different cell types.

New trends in bioprocesses for lignocellulosic biomass and CO2 utilization

Innovation and technology are seen today as key points in the transition to a greener and more sustainable economy. In this sense, the development of new processes able to result in reduced emissions and levels of CO2 in the atmosphere has been considered essential to support this transition and, at the same time, promote economic growth. Several techno-economic and life cycle assessment studies have shown promising data when sugars derived from lignocellulosic biomass are used as carbon source for fermentation processes. The use of CO2 as carbon source for fermentation is another smart concept for reusing this molecule while minimizing its emissions to the atmosphere. However, the large-scale implementation of biomass-based and CO2-based processes still require significant research efforts to result in robust and cost-competitive technologies. This paper discusses some promising approaches able to advance this research area including potential strategies for process intensification (enzymatic hydrolysis using high solid loading, simultaneous saccharification and fermentation, fermentation with downstream process integration), robust microbial strains for application in biomass-based and CO2-based bioprocesses, microbial co-cultivation systems, greener technologies for lignocellulosic biomass fractionation, among others. A critical evaluation of sustainability aspects including techno-economic and life cycle assessment is also provided. Overall, this study contributes with information on innovative trends able to advance the development of greener bioprocesses.

Determination of the Effect of Co-cultivation on the Production and Root Exudation of Flavonoids in Four Legume Species Using LC-MS/MS Analysis.

Flavonoids play a key role in the regulation of plant–plant and plant–microbe interactions, and factors determining their release have been investigated in most of the common forage legumes. However, little is known about the response of flavonoid production and release to co-cultivation with other crop species. This study investigated alterations in the concentration of flavonoids in plant tissues and root exudates in four legumes [alfalfa (Medicago sativa L.), black medic (Medicago polymorpha L.), crimson clover (Trifolium incarnatum L.), and subterranean clover (Trifolium subterraneum L.)] co-cultivated with durum wheat [Triticum turgidum subsp. durum (Desf.) Husn.]. For this purpose, we carried out two experiments in a greenhouse, one with glass beads as growth media for root exudate extraction and one with soil as growth media for flavonoid detection in shoot and root biomass, using LC–MS/MS analysis. This study revealed that interspecific competition with wheat negatively affected legume growth and led to a significant reduction in shoot and root biomass compared with the same legume species grown in monoculture. In contrast, the concentration of flavonoids significantly increased both in legume biomass and in root exudates. Changes in flavonoid concentration involved daidzein, genistein, medicarpin, and formononetin, which have been found to be involved in legume nodulation and regulation of plant–plant interaction. We hypothesize that legumes responded to the co-cultivation with wheat by promoting nodulation and increasing exudation of allelopathic compounds, respectively, to compensate for the lack of nutrients caused by the presence of wheat in the cultivation system and to reduce the competitiveness of neighboring plants. Future studies should elucidate the bioactivity of flavonoid compounds in cereal-legume co-cultivation systems and their specific role in the nodulation process and inter-specific plant interactions such as potential effects on weeds.

Global Metabolomics Reveals That Vibrio natriegens Enhances the Growth and Paramylon Synthesis of Euglena gracilis.

The microalga Euglena gracilis is utilized in the food, medicinal, and supplement industries. However, its mass production is currently limited by its low production efficiency and high risk of microbial contamination. In this study, physiological and biochemical parameters of E. gracilis co-cultivated with the bacteria Vibrio natriegens were investigated. A previous study reports the benefits of E. gracilis and V. natriegens co-cultivation; however, no bacterium growth and molecular mechanisms were further investigated. Our results show that this co-cultivation positively increased total chlorophyll, microalgal growth, dry weight, and storage sugar paramylon content of E. gracilis compared to the pure culture without V. natriegens. This analysis represents the first comprehensive metabolomic study of microalgae-bacterial co-cultivation, with 339 metabolites identified. This co-cultivation system was shown to have synergistic metabolic interactions between microalgal and bacterial cells, with a significant increase in methyl carbamate, ectoine, choline, methyl N-methylanthranilate, gentiatibetine, 4R-aminopentanoic acid, and glu-val compared to the cultivation of E. gracilis alone. Taken together, these results fill significant gaps in the current understanding of microalgae-bacteria co-cultivation systems and provide novel insights into potential improvements for mass production and industrial applications of E. gracilis.

Fast-deployable co-cultivation systems in aquaculture

The article is devoted to the creation of a combined recirculating fish farming and intensive crop production (aquaponics) on the basis of a mobile modular facility, which corresponds to the direction “Transition to highly productive and environmentally friendly agro- development and implementation of systems for the rational use of chemical and biological protection of agricultural plants and animals, storage and efficient processing of agricultural products, creation of safe and high-quality, including functional, food products” of the Strategy of scientific and Technological Development of the Russian Federation, as well as the Forecast of scientific and technological development of the agro-industrial complex of the Russian Federation for the period up to 2030 in terms of the development of specific research areas “Urbanized agriculture: combined technology of recirculating fish farming and intensive crop production”.

Biodegradation of furan aldehydes in lignocellulose hydrolysates

Lignocellulose is the most abundant renewable organic carbon resource on earth. However, due to its complex structure, it must undergo a series of pretreatment processes before it can be efficiently utilized by microorganisms. The pretreatment process inevitably generates typical inhibitors such as furan aldehydes that seriously hinder the growth of microorganisms and the subsequent fermentation process. It is an important research field for bio-refining to recognize and clarify the furan aldehydes metabolic pathway of microorganisms and further develop microbial strains with strong tolerance and transformation ability towards these inhibitors. This article reviews the sources of furan aldehyde inhibitors, the inhibition mechanism of furan aldehydes on microorganisms, the furan aldehydes degradation pathways in microorganisms, and particularly focuses on the research progress of using biotechnological strategies to degrade furan aldehyde inhibitors. The main technical methods include traditional adaptive evolution engineering and metabolic engineering, and the emerging microbial co-cultivation systems as well as functional materials assisted microorganisms to remove furan aldehydes.

Craft Beers Fermented by Potential Probiotic Yeast or Lacticaseibacilli Strains Promote Antidepressant-Like Behavior in Swiss Webster Mice.

This study aimed to produce a probiotic-containing functional wheat beer (PWB) by an axenic culture system with potential probiotic Saccharomyces cerevisiae var boulardii 17 and probiotic-containing functional sour beer (PSB) by a semi-separated co-cultivation system with potential probiotic Lacticaseibacillus paracasei DTA 81 and Saccharomyces cerevisiae S-04. Additionally, results obtained from in vivo behavioral tests with Swiss Webster mice treated with PWB or PSB were provided, which is scarce in the current literature. Although the use of S. boulardii to produce beers is not a novelty, this study demonstrated that S. boulardii 17 performance on sugar wort stills not completely elucidated; therefore, further studies should be considered before using the strain in industrial-scale production. Co-culture systems with lacticaseibacilli strain and S. cerevisiae have been reported in the literature for PSB production. However, lacticaseibacilli survivability in beer can be improved by semi-separated co-cultivation systems, highlighting the importance of growing lacticaseibacilli in the wort before yeast pitching. Besides, kettle hopping must be chosen as the method for hop addition to produce PSB. The dry-hopping method may prevent iso-alpha formation in the wort; however, a tendency to sediment can drag cells at the tank bottom and negatively affect L. paracasei DTA 81 viability. Despite stress factors from the matrices and the stressful conditions encountered during GI transit, potential probiotic S. boulardii 17 and potential probiotic L. paracasei DTA 81 withstood at sufficient doses to promote antidepressant effects in the mice group treated with PWB or PSB, respectively.

Controlled Assays for Phenotyping the Effects of Strigolactone-Like Molecules on Arbuscular Mycorrhiza Development.

Arbuscular mycorrhiza is an ancient symbiosis between most land plants and fungi of the Glomeromycotina, in which the fungi provide mineral nutrients to the plant in exchange for photosynthetically fixed organic carbon. Strigolactones are important signals promoting this symbiosis, as they are exuded by plant roots into the rhizosphere to stimulate activity of the fungi. In addition, the plant karrikin signaling pathway is required for root colonization. Understanding the molecular mechanisms underpinning root colonization by AM fungi, requires the use of plant mutants as well as treatments with different environmental conditions or signaling compounds in standardized cocultivation systems to allow for reproducible root colonization phenotypes. Here we describe how we set up and quantify arbuscular mycorrhiza in the model plants Lotus japonicus and Brachypodium distachyon under controlled conditions. We illustrate a setup for open pot culture as well as for closed plant tissue culture (PTC) containers, for plant-fungal cocultivation in sterile conditions. Furthermore, we explain how to harvest, store, stain, and image AM roots for phenotyping and quantification of different AM structures.

Recent progress on bio-succinic acid production from lignocellulosic biomass.

Succinic acid is a valuable bulk chemical, which has been extensively applied in food, medicine, surfactants and biodegradable plastics industries. As a substitute for chemical raw material, bio-based succinic acid production has received increasing attention due to the depletion of fossil fuels and environmental issues. Meanwhile, the effective bioconversion of lignocellulosic biomass has always been a hot spot of interest owning to the advantages of low expense, abundance and renewability. Consolidated bioprocessing (CBP) is considered to be an alternative approach with outstanding potential, as CBP can not only improve the product yield and productivity, but also reduce the equipment and operating costs. In addition, the current emerging microbial co-cultivation systems provide strong competitiveness for lignocellulose utilization through CBP. This article comprehensively discusses different strategies for the bioconversion of lignocellulose to succinic acid. Based on the principles and technical concepts of CBP, this review focuses on the progress of succinic acid production under different CBP strategies (metabolic engineering based and microbial co-cultivation based). Moreover, the main challenges faced by CBP-based succinic acid fermentation are analyzed, and the future direction of CBP production is prospected.

Customizable 3D-Printed (Co-)Cultivation Systems for In Vitro Study of Angiogenesis.

Due to the ever-increasing resolution of 3D printing technology, additive manufacturing is now even used to produce complex devices for laboratory applications. Personalized experimental devices or entire cultivation systems of almost unlimited complexity can potentially be manufactured within hours from start to finish—an enormous potential for experimental parallelization in a highly controllable environment. This study presents customized 3D-printed co-cultivation systems, which qualify for angiogenesis studies. In these systems, endothelial and mesenchymal stem cells (AD-MSC) were indirectly co-cultivated—that is, both cell types were physically separated through a rigid, 3D-printed barrier in the middle, while still sharing the same cell culture medium that allows for the exchange of signalling molecules. Biochemical-based cytotoxicity assays initially confirmed that the 3D printing material does not exert any negative effects on cells. Since the material also enables phase contrast and fluorescence microscopy, the behaviour of cells could be observed over the entire cultivation via both. Microscopic observations and subsequent quantitative analysis revealed that endothelial cells form tubular-like structures as angiogenic feature when indirectly co-cultured alongside AD-MSCs in the 3D-printed co-cultivation system. In addition, further 3D-printed devices are also introduced that address different issues and aspire to help in varying experimental setups. Our results mark an important step forward for the integration of customized 3D-printed systems as self-contained test systems or equipment in biomedical applications.

Application of Cell Immobilization Technology in Microbial Cocultivation Systems for Biochemicals Production

Due to the heavy metabolic burden and low efficiency of microbial pure cultures during the biotechnological process for biochemicals production, researchers have focused on microbial cocultivation ...

One Sensor for Multiple Colors: Fluorescence Analysis of Microdroplets in Microbiological Screenings by Frequency-Division Multiplexing.

High-speed multiwavelength fluorescence measurements are of paramount importance in microfluidic analytics. However, multicolor detection requires an intricate arrangement of multiple detectors and meticulously aligned filters and dichroic beamsplitters that counteract the simplicity, versatility, and low cost of microfluidic approaches. To break free from the restrictions of optical setup complexity, we introduce a simpler single-sensor setup based on laser-frequency modulation and frequency-division multiplexing (FDM). We modulate lasers to excite the sample with four non-overlapping frequency signals. A single photomultiplier tube detects all the modulated emitted light collected by an optical fiber in the microfluidic chip. Signal demodulation is performed with a lock-in amplifier separating the emitted light into four color channels in real time. This approach not only reduces complexity and provides setup flexibility but also results in improved signal quality and, thus, higher signal-to-noise ratios that translate into increased sensitivity. To validate the setup for high-throughput biological applications, we measured multiple signals from different microorganisms and fluorescently encoded droplet populations for exploring beneficial or antagonistic roles in microbial cocultivation systems, as is the case for antibiotic screening assays.