Cleaner Fish Research Articles

Emerging Materials in Cultivated Meat: Engineering Sustainable Food Solutions – A Review

Emerging Materials in Cultivated Meat: Engineering Sustainable Food Solutions – A Review

Fiber-based Biomaterial Scaffolds for Cell Support towards the Production of Cultivated Meat

Fiber-based Biomaterial Scaffolds for Cell Support towards the Production of Cultivated Meat

Evaluation of plant-based composite materials as 3D printed scaffolds for cell growth and proliferation in cultivated meat applications

Evaluation of plant-based composite materials as 3D printed scaffolds for cell growth and proliferation in cultivated meat applications

Mitochondrial morphology and energy metabolism in reprogrammed porcine expanded potential stem cells.

Expanded potential stem cells (EPSCs) are stem cells that can differentiate into embryonic and extraembryonic lineages, including extraembryonic endoderm and trophoblast lineages. Therefore, EPSCs have great potential in advancing regenerative medicine, elucidating disease mechanisms, and exploring early embryonic development. However, the generation and characterization of EPSCs in pigs have not been thoroughly explored. In this study, we successfully generated porcine EPSCs (pEPSCs). We reprogrammed porcine fetal fibroblasts (PFFs) using an integration-free method with Sendai virus vectors. The resulting pEPSCs expressed key pluripotency markers and demonstrated the ability to differentiate between embryonic and extraembryonic lineages. Notably, reprogramming into pEPSCs was associated with a transformation of mitochondrial morphology from the elongated form observed in PFFs to a globular shape, reflecting potential alterations in energy metabolism. We observed significant remodeling of mitochondrial morphology and a subsequent shift towards glycolytic energy dependence during the reprogramming of PFFs into pEPSCs. Our findings provide valuable insights into the characteristics of EPSCs in pigs and highlight their potential applications in regenerative medicine, disease modeling, and emerging fields such as cell-based meat production.

A scoping review of cultivated meat techno-economic analyses to inform future research directions for scaled-up manufacturing.

Techno-economic analyses offer insights into how industrial cultivated meat (CM) production could achieve price parity with conventional meat. These analyses use scaling practices, data and facility designs for related bioprocessing fields, including large (≥20,000 l) stirred tank bioreactors and suspension-tolerant, continuously available cell lines. This approach is inconsistent with most primary CM literature, which parallels bench-scale tissue engineering. TEAs published to date demonstrate that, under the current technological paradigm, CM is unlikely to be competitive with conventional meat. Scale-up feasibility may hinge on cost-saving areas such as use of plant-based media components, food-grade aseptic conditions and extensive scaling of related supply chains. Research must address knowledge gaps including serum-free differentiation, new bioreactor designs and facility design before CM can become a viable alternative to animal-based meat production.

Reproductive performance of lumpfish (Cyclopterus lumpus, L. 1758) females: Effects of integrated photoperiod and temperature manipulations on sexual maturation and spawning.

A successful control of sexual maturation is crucial for year-round production of lumpfish juveniles destined as cleaner fish in Atlantic salmon aquaculture. This study investigated the combined effects of photoperiod and temperature manipulations on sexual maturation and spawning in lumpfish females. Lumpfish juveniles were exposed to simulated natural and nine-month compressed annual photoperiods, with subsequent temperature elevation. Body weight (BW), condition factor (K), gonadosomatic index (GSI), ovarian development, plasma levels of 17β-estradiol (E2), testosterone (T) and 11-ketotestosterone (11-KT), and spawning were assessed. Compressing the natural photoperiod caused a clear increase and decrease in GSI, T, 11-KT and E2 towards and during the spawning period. Before the temperature elevation, GSI, T, 11-KT, E2 and ovarian development were advanced in the compressed photoperiod. After the temperature elevation, GSI, T, 11-KT and E2 fluctuated more in the compressed photoperiod, while in the natural photoperiod, E2 declined, and GSI, T and 11-KT increased. Spawning was advanced by 1 month in the compressed photoperiod compared to the natural photoperiod. Temperature elevation led to higher levels, earlier peaks and declines of T, 11-KT or E2 in both photoperiods, and advanced spawning by 1.5 months in the compressed photoperiod compared to the natural photoperiod. Temperature elevation also led to increased ovulation recruitment and increased cumulative weight of spawned eggs in the natural photoperiod. Compressing the natural photoperiod and elevating temperature can thus advance sexual maturation and spawning in lumpfish females. Due to the lower amounts of spawned egg weights in the high temperature compressed photoperiod, further studies on effects of photoperiod and timing of temperature manipulations on spawning, fecundity and egg quality could optimize the photothermal manipulations on lumpfish broodstock.

Fat cells bring the flavor to lab-grown meat

Fat cells bring the flavor to lab-grown meat

Drone pupae extract enhances Hanwoo myosatellite cell function for cultivated meat production

Drone pupae extract enhances Hanwoo myosatellite cell function for cultivated meat production

Sorghum Prolamin Scaffolds-Based Hybrid Cultured Meat with Enriched Sensory Properties.

Cultured meat (CM) has been hailed as a sustainable future meat production technology that requires scaffolds to support cell growth. Plant proteins are the most promising raw materials for edible scaffolds but remain underutilized. In this study, kafirin, an abundant, readily available, and nonallergenic prolamin extracted from red sorghum, was explored to fabricate 3D porous sponge-like scaffolds via a simple template-leaching method. The scaffolds featured fully interconnected pores with a high porosity of approximately 84% and mechanical properties of 1.0-1.9 kPa. Porcine skeletal muscle cells (PSCs) and adipose-derived stem cells (ADSCs) could adhere, proliferate, and differentiate on protein scaffolds. Thereafter, a hybrid CM was produced by culturing porcine ADSCs on kafirin scaffolds for 12 days, integrating plant protein-based and cell-based alternatives. The anthocyanins found in red sorghum contributed to the hybrid CM with meat-like color and antioxidative benefits. Moreover, the hybrid CM prototype demonstrated promising potential in providing higher protein content (22.9%) and unique mouthfeel and appearance characteristics, highlighting the viability of sorghum prolamin in promoting CM production.

Plasma-Functionalized Liquids for Decontamination of Viable Tissues: A Comparative Approach

Plasma-functionalized liquids (PFLs) are rich in chemical species, such as ozone, hydrogen peroxide, singlet oxygen, hydroxyl radical and nitrogen oxides, commonly referred to as reactive oxygen and nitrogen species (RONS). Therefore, manifold applications are being investigated for their use in medicine, agriculture, and the environment. Depending on the goal, a suitable plasma source concept for the generation of PFLs has to be determined because the plasma generation setup determines the composition of reactive species. This study investigates three PFL-generating plasma sources—two spark discharges and a flow dielectric barrier discharge (DBD) system—for their efficacy in eliminating microbial contaminants from tissue samples aiming to replace antibiotics in the rinsing process. The final goal is to use these tissues as a cell source for cell-based meat production in bioreactors and thereby completely avoid antibiotics. Initially, a physicochemical characterization was conducted to better understand the decontamination capabilities of PFLs and their potential impact on tissue viability. The results indicate that the flow DBD system demonstrated the highest antimicrobial efficacy due to its elevated reactive species output and the possibility of direct treatment of tissues while tissue integrity remained. Achieving a balance between effective large-scale decontamination and the biocompatibility of PFLs remains a critical challenge.

A new protein source for pet food: cultivated meat

Cultivated meat is an alternative protein source developed to address the sustainability, public health and animal welfare concerns of conventional meat production. Hundreds of startups and academic institutions worldwide are working to make cultivated meat a cost-effective protein source for humans. However, cultivated meat could also be used to feed dogs and cats, contributing to solving the meat supply issues that the growing pet food market has been facing in recent years. The advantages of using cultivated meat as a protein source for pets would include a reduction of the environmental impact of pets' diets, decreased farm animal suffering and several benefits in the One Health framework, as cultivated meat-based pet food would significantly decrease the risk of spreading food safety pathogens, zoonotic diseases and resistant bacteria. The antibiotic-free manufacturing process and the aseptic conditions the cells require to grow in the bioreactors lead to these public health advantages. However, cultivated meat has never been produced at scale for human or pet consumption. Several technical challenges need to be overcome to make cultivated meat-based pet food prices accessible to consumers. As a novel ingredient, there is also no evidence of the effect of feeding cultivated meat to dogs and cats. In principle, cultivated meat can be both safe to be consumed long-term and nutritionally adequate – and with several possibilities for nutritional enhancement, potentially even superior to its conventional counterpart. However, the safety and nutritional soundness of cultivated meat-based products must be demonstrated by manufacturers to gain regulatory approval and favour consumer adoption. Veterinarians, veterinary nurses and technicians will play a critical role in the development of this new ingredient in many aspects, including product development, assessing safety and nutrition, conducting research and informing consumers. This review summarises the benefits and challenges of using cultivated meat as a pet food ingredient.

Neural mechanisms of mutualistic fish cleaning behaviour: a study in the wild.

One crucial interaction for the health of fish communities in coral reefs is performed by cleaner fish by removing ectoparasites from the body of other fish, so-called clients. Studying the underlying mechanisms of this behaviour is essential to understanding how species react to social stimuli and defining the drivers of mutualistic social behaviour. Here, we pinpoint the neural molecular mechanisms in the cleaning behaviour of Labroides dimidiatus in the wild through an in situ interaction experiment at a coral reef in New Caledonia. Five cleaners and clients (Abudefduf saxatilis) were placed into underwater aquaria to interact, while five were not presented with a client. The brain transcriptomes revealed 233 differentially expressed genes in cleaners that were interacting with a client. Among these genes, grin2d, npy, slc6a3 and immediate early genes (IEGs; fosb and fosl1) were related to learning and memory, glutamate and dopamine pathways, which confirm molecular pathways observed in laboratory studies. However, a new potential mechanism was found with npy (neuropeptide Y) as a driver of feeding behaviour. These results show the role of neurotransmitters and IEGs in mutualistic social behaviour, unveiling the mechanism behind the feeding stimulus that leads the cleaner fish to establish mutualistic interactions in coral reefs.

Grifola frondosa extract as a fetal bovine serum supplement for the culture of bovine muscle satellite cells under low serum conditions

Expensive fetal bovine serum (FBS) is a major obstacle to the production of cultivated meat. However, because FBS substitutes do not sufficiently induce cell proliferation, a good alternative is to reduce the amount of FBS and use ingestible additives to promote cell proliferation. In this study, Grifola frondosa extract (GFE) was used to investigate its potential as an additive to promote myogenesis of bovine muscle satellite cells from Hanwoo cattle under low serum conditions (10 % FBS). GFE treated with 10 % FBS only during the proliferation period not only increased cell proliferation and related biomarkers in a concentration-dependent manner (0.78–12.5 μg/mL), but also increased cell differentiation. Additionally, differentiation was promoted when cells were with GFE treated only during the differentiation period. Especially GFE at 12.5 µg/mL induced significantly higher proliferation and differentiation rates than 20 % FBS medium. In particular, compared to treatment alone in the proliferation or differentiation periods, GFE treatment in both periods contributed to an increase in the differentiation rate and significantly enhanced total protein production. The integration of GFE into cultivated meat production presents a promising approach to reducing FBS dependence, lowering costs, and enhancing scalability, aligning with sustainability and consumer acceptance goals.

The Role of Heuristics and Biases in the Choice of Risk Triggers for Novel Foods and GMOs in the European Union

Abstract In the European Union (EU), novel foods and Genetically Modified Organisms (GMOs) are subject to long and costly authorisation procedures and post-marketing requirements. The regulatory frameworks applicable to novel foods and GMOs come into effect based on perceived factors of risk. These “risk triggers” are characteristics of novel foods and GMOs which differentiate them from traditional foods, creating a presumption of risk. Within the EU, consumer acceptance of genetically modified foods and novel foods like insects or cultivated meat is shaped by heuristics and biases, mainly focusing on the “novelty” and “unnaturalness” of these products, resulting in a predominantly negative perception. This paper investigates the close connection between cognitive biases identified in consumer perception literature and the implementation of specific risk triggers in the regulation of novel foods and GMOs in the EU. It subsequently raises concerns about the appropriateness of these risk triggers in forming a presumption of risk for these innovative products.

Cleaner fish with mirror self-recognition capacity precisely realize their body size based on their mental image

Animals exhibiting mirror self-recognition (MSR) are considered self-aware; however, studies on their level of self-awareness remain inconclusive. Recent research has indicated the potential for cleaner fish (Labroides dimidiatus) to possess a sophisticated level of private self-awareness. However, as this study revealed only an aspect of private self-awareness, further investigation into other elements is essential to substantiate this hypothesis. Here, we show that cleaner fish, having attained MSR, construct a mental image of their bodies by investigating their ability to recall body size. A size-based hierarchy governs the outcomes of their confrontations. The mirror-naïve fish behaved aggressively when presented with photographs of two unfamiliar conspecifics that were 10% larger and 10% smaller than their body sizes. After passing the MSR test, they refrained from aggression toward the larger photographs but still behaved aggressively toward the smaller ones without re-examining their mirror images. These findings suggest that cleaner fish accurately recognize their body size based on mental images of their bodies formed through MSR. Additionally, mirror-experienced fish frequently revisited the mirror when presented with an intimidating larger photograph, implying the potential use of mirrors for assessing body size. Our study established cleaner fish as the first non-human animal to be demonstrated to possess private self-awareness.

An efficient serum-free medium for ex vivo expansion of myoblasts from Larimichthys crocea for cultured meat production

The large-scale production of cultured meat has been restricted by high cost of serum, batch difference and unclear composition, thus it is important to develop serum-free media for cell growth. Here we obtained a serum-free medium (SFM), which was suitable for ex vivo culturing of myoblasts from larimichthys crocea. It offered simple composition and high effectiveness that supporting myoblast attachment, expansion and differentiation. Our findings revealed that the optimal SFM consisted of DMEM/F12 base medium, 5 mg/mL bovine serum albumin (BSA), 20 mmol HEPES, 1 % penicillin/streptomycin mixture (PS) and the exogenous additive hydrocortisone. The living cells of SFM could occupy about 65 % of the serum-containing medium (SM). Additionally, differentiation assays showed that myoblasts cultured without serum still differentiated into more muscle tubes, with a higher fusion index than those cultured with serum. Finally, transcriptome sequencing was conducted to demonstrate that hydrocortisone might act as a ligand binding to G protein-coupled receptors, triggering the downstream PI3K/AKT signaling pathway and leading to cell proliferation. Our findings will provide a basis for large-scale cell expansion and cell culture meat production in the future.

Comparative Analysis of Skeletal Muscle Satellite Cells from Hanwoo Steers and Cows for Optimizing Cell-Based Meat Production

Comparative Analysis of Skeletal Muscle Satellite Cells from Hanwoo Steers and Cows for Optimizing Cell-Based Meat Production

Consumer's Cultured Meat Perception and Acceptance Determinants: A Systematic Review and Future Research Agenda

ABSTRACTThe reliance on animal husbandry for protein has caused environmental, social and ethical challenges worldwide, yet the demand for animal‐based food continues to rise. Despite the increasing attention from scholars and professionals on the potential of cultured meat (CM) as a viable alternative protein source, the ensuing scholarly work still lacks coherence and is incomplete and fragmented. Its success also depends heavily on customer acceptance. This study therefore examined peer‐reviewed literature on consumers' perceptions and acceptance of CM. A comprehensive search was conducted on ScienceDirect, Google Scholar and Scopus databases between 2017 and 2022, yielding 54 papers that met the selection criteria. The qualitative synthesis conducted revealed seven themes that had the highest influence on consumers' acceptance of CM. The themes identified were (i) attitudes and traits, (ii) situational impact, (iii) information and nomenclature, (iv) CM properties, (v) risk–benefit perception, (vi) familiarity and awareness and (vii) competition with other alternative proteins. This review also identified demographic predictors of consumers who are most likely to accept CM. The review found that although consumers are curious and willing to try CM, failure to address personal attitudes and traits may lead to failure in adoption. It was also found that strategies that include emotional responses are more effective in the long run.

The thermal dependent biology of cultured lumpfish (Cyclopterus lumpus Linnaeus 1758): Differences due to temperatures during early life and how tolerance is measured

The use of lumpfish as a “cleaner fish” in Atlantic salmon aquaculture is increasing. However, during the summer months, there have been large-scale mortalities of lumpfish at some North Atlantic salmon sea-cage sites. There is evidence that manipulating temperatures during early life can improve the thermal tolerance of fishes. Thus, we reared lumpfish embryos (eggs), larvae and juveniles under different temperature regimes, and measured their metabolic physiology and upper thermal limits, with the goal of better understanding their physiology and mitigating the effects of high summer water temperatures on their welfare. The specific incubation (egg) / rearing temperature combinations were 6 °C / 9 °C (normal production temperatures), 8.5 °C / 9 °C, 6–11 °C / 9 °C, 8.5 °C / 9–11 °C and 6–11 °C / 9–11 °C; with a range of temperatures indicating that fish were exposed to stochastic temperature changes.Hatching success was 61 % in the control (6 °C) group, as compared to ~47 % and 26.5 % in the groups exposed to 8.5 °C and the stochastic temperature regime (6–11 °C), respectively. Groups exposed to stochastic incubation and rearing temperatures also had the lowest survival rate (33.7 %) as opposed to those incubated and reared at constant temperatures (66.1 and 50.7 %) when unexpectedly exposed to high, and variable, ambient water temperatures that were experienced for roughly 7 weeks during rearing (due to abnormal water temperatures in the bay supplying our aquaculture facility). Interestingly, the critical thermal maximum (CTMax), incremental temperature maximum (ITMax) and metabolic capacity (i.e., aerobic scope) of 30-40 g lumpfish did not differ between the groups, and the first two parameters on average were 22.85 ± 0.12 °C and 20.63 ± 0.02 °C, respectively.

Habitat quality effects on the abundance of a coral-dwelling fish across spatial scales.

Microhabitat associated fishes are expected to be negatively affected by coral reef degradation, given that many species are coral dwellers. However, the factors underlying this negative impact and the spatial scale(s) at which it occurs are poorly understood. We explored how habitat quality metrics and host preferences influence fish abundance across multiple spatial scales, using the functionally important cleaner fish Elacatinus evelynae as a study species. We surveyed fish at 10 sites in Curaçao that varied in coral cover and health. At the microhabitat scale, we found that E. evelynae group size increases on large, healthy corals and on some coral host species, namely Montastraea cavernosa. We also found that, although E. evelynae can occupy at least 10 coral host species, it selectively inhabits just three corals: M. cavernosa, Colpophyllia natans, and Diploria labrynthiformis. Scaling up to explore goby abundance along 30-m transects, we did not find a clear relationship between live coral cover and goby abundance. However, goby abundance was substantially higher at one location with elevated coral cover and a high relative abundance of E. evelynae host species. Collectively, these results confirm that E. evelynae abundance is impacted by reef health. They also indicate that the species' long-term persistence may depend on both the maintenance of healthy coral hosts and the gobies' plasticity in host preferences on changing reefscapes. Cryptobenthic fishes such as E. evelynae play a vital role in the ecosystem and understanding drivers of their abundance is important as reefs face increased degradation.