Emerging algal nanotechnology for high-value compounds: A direction to future food production

Sciadonic acid ameliorates cyclophosphamide-induced immunosuppression by modulating the immune response and altering the gut microbiota

BACKGROUND

Cyclophosphamide (Cy) is a frequently used chemotherapeutic drug, but long-term Cy treatment can cause immunosuppression and intestinal mucosal damage. The intestinal mucosal barrier and gut flora play important roles in regulating host metabolism, maintaining physiological functions and protecting immune homeostasis. Dysbiosis of the intestinal flora affects the development of the intestinal microenvironment, as well as the development of various external systemic diseases and metabolic syndrome.

RESULTS

The present study investigated the influence of sciadonic acid (SA) on Cy-induced immunosuppression in mice. The results showed that SA gavage significantly alleviated Cy-induced immune damage by improving the immune system organ index, immune response and oxidative stress. Moreover, SA restored intestinal morphology, improved villus integrity and activated the nuclear factor κB signaling pathway, stimulated cytokine production, and reduced serum lipopolysaccharide (LPS) levels. Furthermore, gut microbiota analysis indicated that SA increased t beneficial bacteria (Alistipes, Lachnospiraceae_NK4A136_group, Rikenella and Odoribacter) and decreased pathogenic bacteria (norank-f-Oscillospiraceae, Ruminococcus and Desulfovibrio) to maintain intestinal homeostasis.

CONCLUSION

The present study provided new insights into the SA regulation of intestinal flora to enhance immune responses. © 2024 Society of Chemical Industry.

Nanotechnology based technological development in biofuel production: Current status and future prospects

Depleting fossil fuels and net carbon emissions associated with their burning have driven the need to find alternative energy sources. Biofuels are near-perfect candidates for alternative energy sources as they are renewable and account for no net CO2 emissions. However, biofuel production must overcome various challenges to compete with conventional fuels. Conventional methods for bioconversion of biomass to biofuel include chemical, thermochemical, and biological processes. Substrate selection and processing, low yield, and total cost of production are some of the main issues associated with biofuel generation. Recently, the uses of nanotechnology and nanoparticles have been explored to improve the biofuel production processes because of their high adsorption, high reactivity, and catalytic properties. The role of these nanoscale particles and nanocatalysts in biomass conversion and their effect on biofuel production processes and yield are discussed in the present article. The applicability of nanotechnology in production processes of biobutanol, bioethanol, biodiesel, biohydrogen, and biogas under biorefinery approach are presented. Different types of nanoparticles, and their function in the bioprocess, such as electron transfer, pretreatment, hydrolysis, microalgae cultivation, lipid extraction, dark and photo fermentation, immobilization, and suppression of inhibitory compounds, are also highlighted. Finally, the current and potential applications of nanotechnology in biorefineries are also discussed.

Host-Delivered RNA Interference for Durable Pest Resistance in Plants: Advanced Methods, Challenges, and Applications

Insect-pests infestation greatly affects global agricultural production and is projected to become more severe in upcoming years. There is concern about pesticide application being ineffective due to insect resistance and environmental toxicity. Reduced effectiveness of Bt toxins also made the scientific community shift toward alternative strategies to control devastating agricultural pests. With the advent of host-delivered RNA interference, also known as host-induced gene silencing, targeted insect genes have been suppressed through genetic engineering tools to deliver a novel insect-pest resistance strategy for combating a number of agricultural pests. This review recapitulates the possible mechanism of host-delivered RNA interference (HD-RNAi), in particular, the silencing of target genes of insect-pests. We emphasize the development of the latest strategies against evolving insect targets including designing of artificial microRNAs, vector constructs, and the benefit of using plastid transformation to transform target RNA-interfering genes. Advantages of using HD-RNAi over other small RNA delivery modes and also the supremacy of HD-RNAi over the CRISPR-Cas system particularly for insect resistance have been described. However, the broader application of this technology is restricted due to its several limitations. Using artificial miRNA designs, the host-delivered RNAi + Bt combinatorial approach and chloroplast transformation can overcome limitations of RNAi. With careful design and delivery approaches, RNAi promises to be extremely valuable and effective plant protection strategy to attain durable insect-pest resistance in crops. Development of transgenic plant using novel strategies to achieve durable resistance against the target insect.

Preparation and in vitro characterization studies of astaxanthin-loaded nanostructured lipid carriers with antioxidant properties

The purpose of this study was to evaluate the astaxanthin-loaded nanostructured lipid carriers (ASX-NLC) prepared using a high-pressure homogenization transport system for local application of astaxanthin. Dynamic light scattering (DLS) and X-ray diffraction (XRD) were used to study the effect of microencapsulation on the properties of ASX-NLC. The mean size of ASX-NLC was about 108.43 ± 0.26 nm and PdI was 0.176 ± 0.002. The ASX-NLC had high encapsulation efficiency which was 95.69 ± 0.13%. Good light stability and temperature stability were shown at the ASX-NLC, indicating that the preparation process was feasible. The 2,2-diphenyl-1-pyridylohydrazinyl (DPPH) scavenging test showed that ASX-NLC could still play an antioxidant role. In vitro release studies showed that compared with an astaxanthin ethanol solution, an ASX-NLC could maintain astaxanthin release more effectively. In vitro permeation studies showed that ASX-NLC could increase astaxanthin retention in the skin. In conclusion, ASX-NLC could significantly enhance astaxanthin accumulation during dermal applications. The research results have important reference significance for local skin applications and provide a basis for the development of nanostructured lipid carriers. ASX-NLC might be suitable carriers for the local application of astaxanthin.

Nanofabrication synthesis and its role in antibacterial, anti-inflammatory, and anticoagulant activities of AgNPs synthesized by Mangifera indica bark extract

The bio-based nanoparticles synthesis and assessment of their potential biomedical applications related research is rapidly emerging. The ability of an aqueous ethanolic bark extract of Mangifera indica to synthesize silver nanoparticles (AgNPs) as well as its antibacterial, anti-inflammatory, and anticancer activities were investigated in this study. Interestingly, the bark extract effectively synthesized the AgNPs, including an absorbance peak at 412 nm and sizes ranging from 56 to 89 nm. The Fourier Transform Infrared spectroscopy (FTIR) analysis confirmed that the presence of most essential functional groups belongs to the most bioactive compounds. Synthesized AgNPs showed fine antibacterial activity against the Urinary Tract Infection (UTI) causing bacterial pathogens such as Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Proteus mirabilis, and Staphylococcus saprophyticus at 50 μg mL^-1 concentrations. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgNPs against these pathogens were found as 12.5 ± 0.8 & 13 ± 0.6, 13.6 ± 0.5 & 14 ± 0.7, 11.5 ± 0.3 & 11.5 ± 0.4, 13 ± 0.8 & 13 ± 0.7, and 11.8 ± 0.4 & 12 ± 0.8 μg mL^-1 respectively. Interestingly, this AgNPs also possesses outstanding anti-inflammatory and anticancer activities as studied against the egg albumin denaturation (85%) inhibition and MCF 7 (Michigan Cancer Foundation-7: breast cancer cells) cell line (cytotoxicity: 80.1%) at 50 μg mL^-1 concentration. Similarly at 50 μg mL^-1 concentration showed 75% of DPPH radical scavenging potential. These activities were dose dependent, and the findings suggest that the M. indica bark aqueous ethanolic extract synthesized AgNPs can be used as antibacterial, anti-inflammatory, and anticancer agents after in-vivo testing.

Plant nanobionics: Fortifying food security via engineered plant productivity

The world's human population is increasing exponentially, increasing the demand for high-quality food sources. As a result, there is a major global concern over hunger and malnutrition in developing countries with limited food resources. To address this issue, researchers worldwide must focus on developing improved crop varieties with greater productivity to overcome hunger. However, conventional crop breeding methods require extensive periods to develop new varieties with desirable traits. To tackle this challenge, an innovative approach termed plant nanobionics introduces nanomaterials (NMs) into cell organelles to enhance or modify plant function and thus crop productivity and yield. A comprehensive review of nanomaterials affect crop yield is needed to guide nanotechnology research. This article critically reviews nanotechnology applications for engineering plant productivity, seed germination, crop growth, enhancing photosynthesis, and improving crop yield and quality, and discusses nanobionic approaches such as smart drug delivery systems and plant nanobiosensors. Moreover, the review describes NM classification and synthesis and human health-related and plant toxicity hazards. Our findings suggest that nanotechnology application in agricultural production could significantly increase crop yields to alleviate global hunger pressures. However, the environmental risks associated with NMs should be investigated thoroughly before their widespread adoption in agriculture.

Carbon nanosheets to unravel the production of bioactive compounds from microalgae: A robust approach in drug discovery

The conglomeration of active pharmaceutical ingredients (APIs) has influenced the development of life-saving drugs. These APIs are customarily synthetic products, albeit with adverse side effects. Thus, to overcome the bottlenecks associated with synthetically derived APIs, the approach of photocatalytically obtaining bioactive compounds from natural ingredients has emerged. Amid the pool of photoactive nanomaterials, this short review emphasizes the intelligent strategy of exploiting photoactive carbon nanosheets to photocatalytically derive bioactive compounds from natural algal biomass to treat many acute or chronic medical conditions. Carbon nanosheets result in phototrophic harvesting of bioactive compounds from microalgae as a result of their being an effective biocatalyst that increases the rate of photosynthesis. To understand the clinical translation of bioactive compounds, the pharmacodynamics of algal bioactive compounds are highlighted to determine the practicality and feasibility of using this green approach for pharmaceutical drug discovery.

A comprehensive review on algal nutraceuticals as prospective therapeutic agent for different diseases

Ongoing research in the food supplement sector provides insightful information regarding algae as a new-generation nutritional supplement and is also referred to as a superfood. Due to the diverse nutritional components, algae have documented numerous health benefits like fighting microbial diseases, hypertension, obesity, and diabetes. Therefore, algae-derived nutraceuticals account for a rapidly expanding market in the food supplements sector. The concept of algal prebiotics and their role in modulating gut microbiota have also been a chief contributor to this. This review evaluates the use of possible algal species and their specific bioactive compounds for the management of several chronic diseases. Proteins, peptides, polysaccharides, phenolics, and vitamins give an insight into the significance of algae in boosting the immune system and improving the body's nutritional makeup. In addition, phyco-compounds such as polysaccharides and polyphenols are also receiving a lot more interest in cosmeceutical applications for protecting skin from photodamage. The incorporation of algae in the diet for the management and prevention of chronic diseases like cancer, lung, and heart disease has been discussed in this review along with their action mechanism. This review provides a brief overview of several bioactive compounds present in micro and macroalgae and their therapeutic effect on lifestyle diseases, gastrointestinal diseases as well as neurodegenerative diseases.

Applications of nanotechnology to combat the problems associated with modern food

Currently, modern lifestyle diseases (LSD) such as cancer, diabetes, hypertension, cardiovascular and thyroid disease are commonly seen among people of different age groups. One of the root causes of this LSD is the type of food that we are eating. Staple crops like rice, sugarcane, vegetables and wheat are grown with the application of agrochemicals (e.g., glyphosate), traces of which are found in our food; after that, it gets ultra-processed in factories; e.g., chips and snacks are fried using saturated fats (trans fat); sugar and wheat (derivatives bread, buns, cookies) are processed using toxic chemicals (bleaching agents). As a result, the nutritional value of food is compromised due to low dietary fiber content and synthetic additives - e.g., sucralose (artificial sweetener) - which promotes inflammation and weakens our immune system, causing our body to become sensitive to microbial infection and many other LSDs. To strengthen the immune system, people start taking synthetically prepared supplements and drugs for a prolonged time, which further deteriorates the body organs and their normal function; e.g., prolonged medication for hypothyroidism poses a risk of heart attack and joint pain. Nanotechnology solves the above problems in the food, nutraceuticals and agriculture sectors. Nanotechnology-based naturally processed products such as nano-nutraceuticals, nanofood, nanofertilizers and nanopesticides will benefit our health. They possess desirable properties such as high bioavailability, targeted delivery, least processing and sustained release. With the help of nanotechnology, we can get nutritional and agrochemical-free food. © 2022 Society of Chemical Industry.

Marine macroalgae polysaccharides-based nanomaterials: an overview with respect to nanoscience applications

Background

Exploration of marine macroalgae poly-saccharide-based nanomaterials is emerging in the nanotechnology field, such as wound dressing, water treatment, environmental engineering, biosensor, and food technology.

Main body

In this article, the current innovation and encroachments of marine macroalgae polysaccharide-based nanoparticles (NPs), and their promising opportunities, for future prospect in different industries are briefly reviewed. The extraction and advancement of various natural sources from marine polysaccharides, including carrageenan, agarose, fucoidan, and ulvan, are highlighted in order to provide a wide range of impacts on the nanofood technology. Further, seaweed or marine macroalgae is an unexploited natural source of polysaccharides, which involves numerous different phytonutrients in the outermost layer of the cell and is rich in sulphated polysaccharides (SP), SP-based nanomaterial which has an enhanced potential value in the nanotechnology field.

Conclusion

At the end of this article, the promising prospect of SP-based NPs and their applications in the food sector is briefly addressed.

Macroalgae Specialized Metabolites: Evidence for Their Anti-Inflammatory Health Benefits

Inflammation is an organism's response to chemical or physical injury. It is split into acute and chronic inflammation and is the last, most significant cause of death worldwide. Nowadays, according to the World Health Organization (WHO), the greatest threat to human health is chronic disease. Worldwide, three out of five people die from chronic inflammatory diseases such as stroke, chronic respiratory diseases, heart disorders, and cancer. Nowadays, anti-inflammatory drugs (steroidal and non-steroidal, enzyme inhibitors that are essential in the inflammatory process, and receptor antagonists, among others) have been considered as promising treatments to be explored. However, there remains a significant proportion of patients who show poor or incomplete responses to these treatments or experience associated severe side effects. Seaweeds represent a valuable resource of bioactive compounds associated with anti-inflammatory effects and offer great potential for the development of new anti-inflammatory drugs. This review presents an overview of specialized metabolites isolated from seaweeds with in situ and in vivo anti-inflammatory properties. Phlorotannins, carotenoids, sterols, alkaloids, and polyunsaturated fatty acids present significant anti-inflammatory effects given that some of them are involved directly or indirectly in several inflammatory pathways. The majority of the isolated compounds inhibit the pro-inflammatory mediators/cytokines. Studies have suggested an excellent selectivity of chromene nucleus towards inducible pro-inflammatory COX-2 than its constitutive isoform COX-1. Additional research is needed to understand the mechanisms of action of seaweed's compounds in inflammation, given the production of sustainable and healthier anti-inflammatory agents.

Global seaweed farming and processing in the past 20 years

Seaweed has emerged as one of the most promising resources due to its remarkable adaptability, short development period, and resource sustainability. It is an effective breakthrough to alleviate future resource crises. Algal resources have reached a high stage of growth in the past years due to the increased output and demand for seaweed worldwide. Several aspects global seaweed farming production and processing over the last 20 years are reviewed, such as the latest situation and approaches of seaweed farming. Research progress and production trend of various seaweed application are discussed. Besides, the challenges faced by seaweed farming and processing are also analyzed, and the related countermeasures are proposed, which can provide advice for seaweed farming and processing. The primary products, extraction and application, or waste utilization of seaweed would bring greater benefits with the continuous development and improvement of applications in various fields.

Graphical Abstract

Algae as Food in Europe: An Overview of Species Diversity and Their Application

Algae have been consumed for millennia in several parts of the world as food, food supplements, and additives, due to their unique organoleptic properties and nutritional and health benefits. Algae are sustainable sources of proteins, minerals, and fiber, with well-balanced essential amino acids, pigments, and fatty acids, among other relevant metabolites for human nutrition. This review covers the historical consumption of algae in Europe, developments in the current European market, challenges when introducing new species to the market, bottlenecks in production technology, consumer acceptance, and legislation. The current algae species that are consumed and commercialized in Europe were investigated, according to their status under the European Union (EU) Novel Food legislation, along with the market perspectives in terms of the current research and development initiatives, while evaluating the interest and potential in the European market. The regular consumption of more than 150 algae species was identified, of which only 20% are approved under the EU Novel Food legislation, which demonstrates that the current legislation is not broad enough and requires an urgent update. Finally, the potential of the European algae market growth was indicated by the analysis of the trends in research, technological advances, and market initiatives to promote algae commercialization and consumption.

Prospects of algae-based green synthesis of nanoparticles for environmental applications

Green synthesis of nanoparticles (NPs) has emerged as an eco-friendly alternative to produce nanomaterials with diverse physical, chemical, and biological characteristics. Previously used, physical and chemical methods involve the production of toxic byproducts, costly instrumentation, and energy-intensive experimental processes thereby, limiting their applicability. Biogenic synthesis of nanoparticles has come forward as a potential alternative, providing an eco-friendly, cost-effective, and energy-efficient approach for the synthesis of a diverse range of NPs. Several biological entities are employed in the biosynthesis of NPs including bacteria, fungi, and algae. However, the distinguishing characteristics of microalgae and cyanobacteria make them promising candidates for NPs synthesis because of their higher growth rate, substantially higher rate of sequestering CO₂, hyperaccumulation of heavy metals, absence of toxic byproducts, minimum energy input, and employment of biomolecules (pigments and enzymes) as reducing and capping agents. Algal extract, being a natural reducing and capping agent, serves as a living cell factory for the efficient green synthesis of nanoparticles. Physiological and biological methods allow algal cells to uptake heavy metals and utilize them as nutrient source to generate biomass by regulating their metabolic processes. Despite their enormous potential, studies on the microalgae-based synthesis of nanoparticles for the removal of toxic pollutants from wastewater remained an unexplored research area in the literature. This review was aimed to summarize the recent advancements and prospects in the algae-based synthesis of nanoparticles for environmental applications particularly treating the wastewater.

A state-of-the-art review on algae pyrolysis for bioenergy and biochar production

Algae, as a feedstock with minimum land footprint, is considered a promising biomass for sustainable fuels, chemicals, and materials. Unlike lignocellulosic biomass, algae consist mainly of lipids, carbohydrates, and proteins. This review focusses on the bio-oil and biochar co-products of algae-pyrolysis and presents the current state-of-the-art in the pyrolysis technologies and key applications of algal biochar. Algal biochar holds potential to be a cost-effective fertilizer, as it has high P, N and other nutrient contents. Beyond soil applications, algae-derived biochar has many other applications, such as wastewater-treatment, due to its porous structure and strong ion-exchange capacity. High specific capacitance and stability also make algal biochar a potential supercapacitor material. Furthermore, algal biochar can be great catalysts (or catalyst supports). This review sheds light on a wide range of algae-pyrolysis related topics, including advanced-pyrolysis techniques and the potential biochar applications in soil amendment, energy storage, catalysts, chemical industries, and wastewater-treatment plants.

Algae bioprocess to deal with cosmetic chemical pollutants in natural ecosystems: A comprehensive review

Elevated demand and extensive exploitation of cosmetics in day-to-day life have hiked up its industrial productions worldwide. Organic and inorganic chemicals like parabens, phthalates, sulfates, and so forth are being applied as constituents towards the formulations, which tend to be the mainspring ecological complication due to their enduring nature and accumulation properties in various sections of the ecosystem. These cosmetic chemicals get accrued into the terrestrial and aquatic systems on account of various anthropogenic activities involving agricultural runoff, industrial discharge, and domestic effluents. Recently, the use of microbes for remediating persistent cosmetic chemicals has gained immense interest. Among different forms of the microbial community being applied as an environmental beneficiary, algae play a vital role in both terrestrial and aquatic ecosystems by their biologically beneficial metabolites and molecules, resulting in the biobenign and efficacious consequences. The use of various bacterial, fungal, and higher plant species has been studied intensely for their bioremediation elements. The bioremediating property of the algal cells through biosorption, bioassimilation, biotransformation, and biodegradation has made it favorable for the removal of persistent and toxic pollutants from the environment. However, the research investigation concerned with the bioremediation potential of the algal kingdom is limited. This review summarizes and provides updated and comprehensive insights into the potential remediation capabilities of algal species against ecologically hazardous pollutants concerning cosmetic chemicals.

Biofuel production from Macroalgae: present scenario and future scope

The current fossil fuel reserves are not sufficient to meet the increasing demand and very soon will become exhausted. Pollution, global warming, and inflated oil prices have led the quest for renewable energy sources. Macroalgae (green, brown, and red marine seaweed) is gaining popularity as a viable and promising renewable source for biofuels production. Numerous researches have been conducted to access the potential of macroalgae for generating diverse bioproducts such as biofuels. The existence of components such as carbohydrates and lipids, and the lack or deficiency of lignin, create macroalgae an enviable feedstock for biofuels generation. This review briefly covers the potential macroalgal species promoting the production of biofuels and their cultivation methods. It also illustrates the biofuel generation pathway and its efficiency along with the recent techniques to accelerate the product yield. In addition, the current analysis focuses on a cost-effective sustainable generation of biofuel along with commercialization and scaleup.