aNew trends in biotechnological applications of photosynthetic microorganisms

Phototactic/Photosynthetic/Magnetic-Powered Chlamydomonas Reinhardtii-Metal-Organic Frameworks Micro/Nanomotors for Intelligent Thrombolytic Management and Ischemia Alleviation

Thrombosis presents a critical health threat globally, with high mortality and incidence rates. Clinical treatment faces challenges such as low thrombolytic agent bioavailability, thrombosis recurrence, ischemic hypoxia damage, and neural degeneration. This study developed biocompatible Chlamydomonas Reinhardtii micromotors (CHL) with photo/magnetic capabilities to address these needs. These CHL micromotors, equipped with phototaxis and photosynthesis abilities, offer promising solutions. A core aspect of this innovation involves incorporating polysaccharides (glycol chitosan (GCS) and fucoidan (F)) into ferric Metal-organic frameworks (MOFs), loaded with urokinase (UK), and subsequently self-assembled onto the multimodal CHL, forming a core-shell microstructure (CHL@GCS/F-UK-MOF). Under light-navigation, CHL@GCS/F-UK-MOF is shown to penetrate thrombi, enhancing thrombolytic biodistribution. Combining CHL@GCS/F-UK-MOF with the magnetic hyperthermia technique achieves stimuli-responsive multiple-release, accelerating thrombolysis and rapidly restoring blocked blood vessels. Moreover, this approach attenuates thrombi-induced ischemic hypoxia disorder and tissue damage. The photosynthetic and magnetotherapeutic properties of CHL@GCS/F-UK-MOF, along with their protective effects, including reduced apoptosis, enhanced behavioral function, induced Heat Shock Protein (HSP), polarized M2 macrophages, and mitigated hypoxia, are confirmed through biochemical, microscopic, and behavioral assessments. This multifunctional biomimetic platform, integrating photo-magnetic techniques, offers a comprehensive approach to cardiovascular management, advancing related technologies.

Harnessing and Mimicking Bacterial Features to Combat Cancer: From Living Entities to Artificial Mimicking Systems

Bacterial-derived micro-/nanomedicine has garnered considerable attention in anticancer therapy, owing to the unique natural features of bacteria, including specific targeting ability, immunogenic benefits, physicochemical modifiability, and biotechnological editability. Besides, bacterial components have also been explored as promising drug delivery vehicles. Harnessing these bacterial features, cutting-edge physicochemical and biotechnologies have been applied to attenuated tumor-targeting bacteria with unique properties or functions for potent and effective cancer treatment, including strategies of gene-editing and genetic circuits. Further, the advent of bacteria-inspired micro-/nanorobots and mimicking artificial systems has furnished fresh perspectives for formulating strategies for developing highly efficient drug delivery systems. Focusing on the unique natural features and advantages of bacteria, this review delves into advances in bacteria-derived drug delivery systems for anticancer treatment in recent years, which has experienced a process from living entities to artificial mimicking systems. Meanwhile, a summary of relative clinical trials is provided and primary challenges impeding their clinical application are discussed. Furthermore, future directions are suggested for bacteria-derived systems to combat cancer.

Biomedical engineering utilizing living photosynthetic cyanobacteria and microalgae: Current status and future prospects

Cyanobacteria are the only prokaryotes capable of performing oxygenic photosynthesis on Earth. Besides their traditional roles serving as primary producers, cyanobacteria also synthesize abundant secondary metabolites including carotenoids, alkaloids, peptides, which have been reported to possess medicinal potentials. More importantly, the advancement of synthetic biology technology has further expanded their potential biomedical applications especially using living/engineered cyanobacteria, providing promising and attractive strategies for future disease treatments. To improve the understanding and to facilitate future applications, this review aims to discuss the current status and future prospects of cyanobacterial-based biomedical engineering. Firstly, specific properties of cyanobacteria related with biomedical applications like their natural products of bioactive compounds and heavy metal adsorption were concluded. Subsequently, based on these properties of cyanobacteria, we discussed the progress of their applications in various disease models like hypoxia microenvironment alleviation, wound healing, drug delivery, and so on. Finally, the future prospects including further exploration of cyanobacteria secondary metabolites, the integration of bioactive compounds synthesized by cyanobacteria in situ with medical diagnosis and treatment, and the optimization of in vivo application were critically presented. The review will promote the studies related with cyanobacteria-based biomedical engineering and its practical application in clinical trials in the future.

Nature-Inspired Thylakoid-Based Photosynthetic Nanoarchitectures for Biomedical Applications

"Drawing inspiration from nature" offers a wealth of creative possibilities for designing cutting-edge materials with improved properties and performance. Nature-inspired thylakoid-based nanoarchitectures, seamlessly integrate the inherent structures and functions of natural components with the diverse and controllable characteristics of nanotechnology. These innovative biomaterials have garnered significant attention for their potential in various biomedical applications. Thylakoids possess fundamental traits such as light harvesting, oxygen evolution, and photosynthesis. Through the integration of artificially fabricated nanostructures with distinct physical and chemical properties, novel photosynthetic nanoarchitectures can be catalytically generated, offering versatile functionalities for diverse biomedical applications. In this article, an overview of the properties and extraction methods of thylakoids are provided. Additionally, the recent advancements in the design, preparation, functions, and biomedical applications of a range of thylakoid-based photosynthetic nanoarchitectures are reviewed. Finally, the foreseeable challenges and future prospects in this field is discussed.

An acidic exopolysaccharide α-D-galacturono-β-D-glucan produced by the cyanobacterium Scytonema sp

Some cyanobacteria produce a wide range of secondary metabolites, some of which are of industrial interest. Exopolysaccharides, particularly interesting among them, represent relatively complex primary structures with interesting bioactivity, biodegradability and specific applications. Cultivation of the freshwater cyanobacterium Scytonema sp. provided a proteoglycan-type exopolysaccharide with a relatively low yield and a wide spectrum of molecular weights (Mw) ranging from 2.2 to 1313 × 103 g/mol. Chemical analyses detected the presence of carbohydrates (46 wt%), proteins (10 wt%) and uronic acids (8 wt%). Monosaccharide analysis revealed up to seven neutral sugars with a dominance of glucose (23.6 wt%), galactose (7.4 wt%) and fucose (5.0 wt%) residues, while the others had a much lower content (0.9-3.4 wt%). The presence of galacturonic acid (8.0 wt%) indicated the appearance of ionic type of exopolysaccharide. A preliminary structural study indicated that the α-D-galacturono-β-D-glucan forms a dominant part of Scytonema sp. exopolymer. Its backbone is composed of two 1,6-linked and one 1,2-linked β-D-Glcp residues, which is branched at O6 by side chains composed of α-D-GalAp(1 → 2)-β-D-Glcp(1→ dimer or monomeric β-D-Glcp(1→ residue.

Biocompatibility of Synechococcus sp. PCC 7002 with Human Dermal Cells In Vitro

Being the green gold of the future, cyanobacteria have recently attracted considerable interest worldwide. This study investigates the adaptability and biocompatibility of the cyanobacterial strain Synechococcus sp. PCC 7002 with human dermal cells, focusing on its potential application in biomedical contexts. First, we investigated the adaptability of Synechococcus PCC 7002 bacteria to human cell culture conditions. Next, we evaluated the biocompatibility of cyanobacteria with common dermal cells, like 3T3 fibroblasts and HaCaT keratinocytes. Therefore, cells were directly and indirectly cocultured with the corresponding cells, and we measured metabolic activity (AlamarBlue assay) and proliferation (cell count and PicoGreen assay). The lactate dehydrogenase (LDH) assay was performed to determine the cytotoxic effect of cyanobacteria and their nutrition medium on human dermal cells. The cyanobacteria exhibited exponential growth under conventional human cell culture conditions, with the temperature and medium composition not affecting their viability. In addition, the effect of illumination on the proliferation capacity was investigated, showing a significant impact of light exposure on bacterial growth. The measured oxygen production under hypoxic conditions demonstrated a sufficient oxygen supply for further tissue engineering approaches depending on the number of bacteria. There were no significant adverse effects on human cell viability and growth under coculture conditions, whereas the LDH assay assessed signs of cytotoxicity regarding 3T3 fibroblasts after 2 days of coculturing. These negative effects were dismissed after 4 days. The findings highlight the potential of Synechococcus sp. PCC 7002 for integration into biomedical approaches. We found no cytotoxicity of cyanobacteria on 3T3 fibroblasts and HaCaT keratinocytes, thus paving the way for further in vivo studies to assess long-term effects and systemic reactions.

Studying the impact of phycoerythrin on antioxidant and antimicrobial activity of the fresh rainbow trout fillets

Marine cyanobacteria present a significant potential source of new bioactive compounds with vast structural diversity and relevant antimicrobial and antioxidant activities. Phycobiliproteins (PBPs) like phycocyanin (PC), phycoerythrin (PE), and water-soluble cyanobacterial photosynthetic pigments, have exhibited strong pharmacological activities and been used as natural food additives. In this study, phycoerythrin (PE) isolated from a marine strain of cyanobacterium Nostoc sp. Ft salt, was applied for the first time as a natural antimicrobial as well as an antioxidant to increase the shelf life of fresh rainbow trout i.e., (Oncorhynchus mykiss) fillets. Fresh trout fillets were marinated in analytical grade PE (3.9 μg/mL) prepared in citric acid (4 mg/mL), and stored at 4 °C and 8 °C for 21 days. Microbiological analysis, antioxidant activity and organoleptic evaluation of both control and treated fish fillets were then statistically compared. The results demonstrated noticeable (P < 0.05) differences in the microbial counts, antioxidant activity, and organoleptic characteristic values between PE-treated and non-treated groups. In addition, we observed that treating fresh fish fillets with a PE solution leads to a significant increase in shelf life by at least 14 days. Consequently, PE could be an alternative to synthetic chemical additives since it does not contain the potentially dangerous residues of the synthetic chemical additives and is thus healthier to the consumers.

A potential paradigm in CRISPR/Cas systems delivery: at the crossroad of microalgal gene editing and algal-mediated nanoparticles

Microalgae as the photosynthetic organisms offer enormous promise in a variety of industries, such as the generation of high-value byproducts, biofuels, pharmaceuticals, environmental remediation, and others. With the rapid advancement of gene editing technology, CRISPR/Cas system has evolved into an effective tool that revolutionised the genetic engineering of microalgae due to its robustness, high target specificity, and programmability. However, due to the lack of robust delivery system, the efficacy of gene editing is significantly impaired, limiting its application in microalgae. Nanomaterials have become a potential delivery platform for CRISPR/Cas systems due to their advantages of precise targeting, high stability, safety, and improved immune system. Notably, algal-mediated nanoparticles (AMNPs), especially the microalgae-derived nanoparticles, are appealing as a sustainable delivery platform because of their biocompatibility and low toxicity in a homologous relationship. In addition, living microalgae demonstrated effective and regulated distribution into specified areas as the biohybrid microrobots. This review extensively summarised the uses of CRISPR/Cas systems in microalgae and the recent developments of nanoparticle-based CRISPR/Cas delivery systems. A systematic description of the properties and uses of AMNPs, microalgae-derived nanoparticles, and microalgae microrobots has also been discussed. Finally, this review highlights the challenges and future research directions for the development of gene-edited microalgae.

Algae: A Robust Living Material Against Cancer

Cancer is the second leading cause of death worldwide. Its incidence has been increasing in recent years, and it is becoming a major threat to human health. Conventional cancer treatment strategies, including surgery, chemotherapy, and radiotherapy, have faced problems such as drug resistance, toxic side effects and unsatisfactory therapeutic efficacy. Therefore, better development and utilization of biomaterials can improve the specificity and efficacy of tumor therapy. Algae, as a novel living material, possesses good biocompatibility. Although some reviews have elucidated several algae-based biomaterials for cancer treatment, the majority of the literature has focused on a limited number of algae. As a result, there is currently a lack of comprehensive reviews on the subject of anticancer algae. This review aims to address this gap by conducting a thorough examination of algal species that show potential for anticancer activity. Furthermore, our review will also elucidate the engineering strategies of algae and discuss the challenges and prospects associated with their implementation.

Emerging Applications of Chlorella sp. and Spirulina (Arthrospira) sp

Chlorella sp. and Spirulina (Arthrospira) sp. account for over 90% of the global microalgal biomass production and represent one of the most promising aquiculture bioeconomy systems. These microorganisms have been widely recognized for their nutritional and therapeutic properties; therefore, a significant growth of their market is expected, especially in the nutraceutical, food, and beverage segments. However, recent advancements in biotechnology and environmental science have led to the emergence of new applications for these microorganisms. This paper aims to explore these innovative applications, while shedding light on their roles in sustainable development, health, and industry. From this state-of-the art review, it was possible to give an in-depth outlook on the environmental sustainability of Chlorella sp. and Spirulina (Arthrospira) sp. For instance, there have been a variety of studies reported on the use of these two microorganisms for wastewater treatment and biofuel production, contributing to climate change mitigation efforts. Moreover, in the health sector, the richness of these microalgae in photosynthetic pigments and bioactive compounds, along with their oxygen-releasing capacity, are being harnessed in the development of new drugs, wound-healing dressings, photosensitizers for photodynamic therapy, tissue engineering, and anticancer treatments. Furthermore, in the industrial sector, Chlorella sp. and Spirulina (Arthrospira) sp. are being used in the production of biopolymers, fuel cells, and photovoltaic technologies. These innovative applications might bring different outlets for microalgae valorization, enhancing their potential, since the microalgae sector presents issues such as the high production costs. Thus, further research is highly needed to fully explore their benefits and potential applications in various sectors.

Oxygenated Wound Dressings for Hypoxia Mitigation and Enhanced Wound Healing

Oxygen is a critical factor that can regulate the wound healing processes such as skin cell proliferation, granulation, re-epithelialization, angiogenesis, and tissue regeneration. However, hypoxia, a common occurrence in the wound bed, can impede normal healing processes. To enhance wound healing, oxygenation strategies that could effectively increase wound oxygen levels are effective. The present review summarizes wound healing stages and the role of hypoxia in wound healing and overviews current strategies to incorporate various oxygen delivery or generating materials for wound dressing, including catalase, nanoenzyme, hemoglobin, calcium peroxide, or perfluorocarbon-based materials, in addition to photosynthetic bacteria and hyperbaric oxygen therapy. Mechanism of action, oxygenation efficacy, and potential benefits and drawbacks of these dressings are also discussed. We conclude by highlighting the importance of design optimization in wound dressings to address the clinical needs to improve clinical outcomes.

Engineered photoresponsive biohybrids for tumor therapy

Engineered biohybrids have recently emerged as innovative biomimetic platforms for cancer therapeutic applications. Particularly, engineered photoresponsive biohybrids hold tremendous potential against tumors due to their intriguing biomimetic properties, photoresponsive ability, and enhanced biotherapeutic functions. In this review, the design principles of engineered photoresponsive biohybrids and their latest progresses for tumor therapy are summarized. Representative engineered photoresponsive biohybrids are highlighted including biomolecules-associated, cell membrane-based, eukaryotic cell-based, bacteria-based, and algae-based photoresponsive biohybrids. Representative tumor therapeutic modalities of the engineered photoresponsive biohybrids are presented, including photothermal therapy, photodynamic therapy, synergistic therapy, and tumor therapy combined with tissue regeneration. Moreover, the challenges and future perspectives of these photoresponsive biohybrids for clinical practice are discussed.