High-value Molecules Research Articles

Electric fields to support microalgae growth with a differentiated biochemical composition

Microalgae are a group of microorganisms well-known for their high metabolic plasticity and biomass with commercial interest for several industries. In the present work, the influence of in-situ electric field application (INEF) on the growth and biochemical composition of Pavlova gyrans was, for the first time, assessed. Electrical protocols were tested, namely by applying INEF in different growth stages, in varying treatment times and even by combining it with dark phase of cells' photoperiod. INEF did not promote a stimulatory effect on growth but influenced the biochemical composition of P. gyrans – maximum increases of 74.9 and 66.2 % in the chlorophyll a and carotenoid content and of 4.72, 18.7 and 5.41 % in the lipid, carbohydrate and protein content were observed in independent experiments. Hence, with this study, the potential of INEF application as a strategy to modulate growth and to promote biochemical composition alterations was proven. Industrial relevanceMicroalgae, with their unique ability to efficiently convert sunlight and carbon dioxide into biomass, offer a sustainable platform for the synthesis of diverse bioactive compounds. By subjecting microalgae to controlled electric stress conditions, their metabolic pathways can be redirected towards the production of specific target compounds. This strategy has the potential to enhance the yield of high-value molecules, including biofuels, pharmaceuticals, nutraceuticals, and pigments, whilst minimizing resource inputs. Additionally, metabolic stress responses in microalgae often trigger the accumulation of secondary metabolites with bioactive properties. Harnessing the metabolic plasticity of microalgae through controlled stress manipulation represents a cutting-edge strategy for sustainable and economically viable bioproduction systems that align with the goals of green chemistry and circular economy principles.

Carotenoid content in Ulva lactuca cultivated under aquaculture conditions and collected from intertidal beds in southeastern Brazil: biotechnological implications for biomass use and storage

Ulva lactuca is an edible green macroalga (Chlorophyta) that can be produced in cultivation systems; it is a natural source of high-value molecules. Ulva lactuca produces metabolites including carotenoids, which are pigments with antioxidant properties that are in high demand in the health and nutraceutical industries and improve the nutritional quality of U. lactuca biomass. We studied the carotenoid and chlorophyll content in U. lactuca thalli collected in 3 different environments in the state of Rio de Janeiro, Brazil: the intertidal beds of the urban beaches of Arpoador and Boa Viagem and a continental integrated multi-trophic aquaculture (IMTA) facility. Carotenoid conservation was evaluated during 1 week, 2 weeks, and 4 weeks of storage. We compared the molecules in fresh U. lactuca collected during the dry season (July 2018) and rainy season (February 2019). The content of carotenoids, such as β-carotene + zeaxanthin, lutein + antheraxanthin, violaxanthin, neoxanthin, and their derivatives (aurochrome and auroxanthin), were analyzed in 100% acetone extracts by ultraviolet visible (UV/vis) spectrophotometry and monitored by thin layer chromatography (TLC) and proton nuclear magnetic resonance (1H-NMR). The extracts of dried U. lactuca produced in the IMTA facility presented higher pigment yields than the dried biomass collected from intertidal beds. Over 4 weeks of storage, carotenoids were well conserved in U. lactuca produced in the IMTA facility, in contrast to what was observed in U. lactuca collected from the intertidal beds, which showed carotenoid losses. In addition, we observed differences in carotenoid content between the dry and rainy seasons in U. lactuca collected from Boa Viagem Beach. However, the U. lactuca collected from Arpoador Beach or produced by the IMTA facility only exhibited significant differences in chlorophyll content. We conclude that U. lactuca produced by the IMTA facility constitutes a potential source of pigments such as β-carotene, lutein, and violaxanthin.

Waste Biomass Pretreatments for Biogas Yield Optimization and for the Extraction of Valuable High-Added-Value Products: Possible Combinations of the Two Processes toward a Biorefinery Purpose

Second- and third-generation biorefineries enable the sustainable management of biomasses within the framework of circular economy principles. This approach aims to minimize waste biomass while generating high-value molecules and bio-energy, such as biogas. Biogas production is achieved via anaerobic digestion, a process where microorganisms metabolize organic compounds in the absence of oxygen to primarily produce CO2 and CH4. The efficiency of this process is closely linked to the composition of the biomass and, sometimes, characteristics of the initial matrix can impede the process. To address these challenges, various pretreatments are employed to enhance digestion efficiency and mitigate issues associated with biomass complexity. However, the implementation of pretreatments can be energy-intensive and costly. The extraction of valuable molecules from biomass for various applications can represent a form of pretreatment. This extraction process selectively removes recalcitrant molecules such as lignin and cellulose, which can hinder biodegradation, thereby adding new value to the biomass. These extracted molecules not only contribute to improved anaerobic digestion efficiency but also offer potential economic benefits by serving as valuable inputs across diverse industrial sectors. This article presents a detailed state of the art of the most widespread biomass pretreatments and specifies when biomass is pretreated to improve the biogas yield and, in contrast, when it is treated to extract high-added-value products. Finally, in order to define if the same treatment can be simultaneously applied for both goals, an experimental section was dedicated to the production of biogas from untreated olive mill wastewater and the same biomass after being freeze-dried and after the extraction of polyphenols and flavonoids. The use of pretreated biomass effectively improved the biogas production yield: the untreated olive mill wastewater led to the production of 147 mL of biogas, while after freeze-drying and after polyphenols/flavonoids extraction, the production was, respectively, equal to 169 mL and 268 mL of biogas.

Exploring industrial lignocellulosic waste: Sources, types, and potential as high-value molecules

Lignocellulosic biomass has a promising role in a circular bioeconomy and may be used to produce valuable molecules for green chemistry. Lignocellulosic biomass, such as food waste, agricultural waste, wood, paper or cardboard, corresponded to 15.7% of all waste produced in Europe in 2020, and has a high potential as a secondary raw material for industrial processes. This review first presents industrial lignocellulosic waste sources, in terms of their composition, quantities and types of lignocellulosic residues. Secondly, the possible high added-value chemicals obtained from transformation of lignocellulosic waste are detailed, as well as their potential for applications in the food industry, biomedical, energy or chemistry sectors, including as sources of polyphenols, enzymes, bioplastic precursors or biofuels. In a third part, various available transformation treatments, such as physical treatments with ultrasound or heat, chemical treatments with acids or bases, and biological treatments with enzymes or microorganisms, are presented. The last part discusses the perspectives of the use of lignocellulosic waste and the fact that decreasing the cost of transformation is one of the major issues for improving the use of lignocellulosic biomass in a circular economy and green chemistry approach, since it is currently often more expensive than petroleum-based counterparts.

Screening of efficient microalgae strains isolated from Tunisian ecosystems: Assessment of algal growth rate and added-value bioproducts for biorefinery applications

Microalgae are highly diverse organisms with significant applications in the production of high-value molecules and biodiesel from microalgae rich in oils. In this study, our main objectives were to evaluate the potential applications of four isolated microalgae strains, namely Scenedesmus sp., Nannochloris sp., Oscillatoria sp., and Amphora sp., which were selected from the natural environment. These strains were batch cultured, and their growth was monitored. We determined the content of chlorophyll a, carotenoids, and lipids, and analyzed the fatty acid profile of each cultivated strain to assess their lipid potential for biodiesel production. Our findings revealed that these strains exhibited high biomass production, ranging from 3000 mg. L−1 for Amphora sp. to 3800 mg. L−1 for Oscillatoria sp. Notably, Oscillatoria sp. and Scenedesmus sp. were found to be the richest in saturated fatty acids, with 10.68% and 9.36% of dry cell weight, respectively, suggesting their potential use in the production of biodiesel from microalgal oils with possibility of blending with other oils feedstock to improve biodiesel final quality. Furthermore, our results showed that the Nannochloris sp. strain could be cultivated to extract pigments for various applications, as it exhibited high levels of chlorophyll a (38.43 mg. L−1) and carotenoids (4.153 μg. mL−1).

Combined effect of LED light color and nitrogen source on growth, pigments composition and oxidative stress in Arthrospira platensis

Artificial lighting with light-emitting diodes (LED) is proposed as a suitable solution to reach stable yearly production of high value molecules from microalgae under unfavorable climates. However, available studies are inconsistent regarding the effect of LED color on cultures performance. This study examined the response of Arthrospira platensis to three different LED lighting conditions (white, red, and red-blue 70:30) when is grown in three media with different nitrogen composition. Growth, phycobiliproteins and lipophilic pigments content were determined. In addition, antioxidant enzymes (GST, lipid peroxidation) and morphology were analyzed to enlighten new perspectives on the health status of microalgae production.The highest biomass production (2.13 g/L) was achieved under red LED when Zarrouk medium was supplemented with urea. Regarding pigment production (phycobilins, chlorophyll a and β- carotene), the most desirable combination was red: blue together with urea supplementation. In addition, this combination showed a high biomass production (2.03 g/L) and low expression of antioxidant enzymatic activity. This research shows a novel combination of LED technology and nutrients to enhance microalgae biomass production and high value metabolites with a lower economic cost.

Molecular-level architecture of Chlamydomonas reinhardtii’s glycoprotein-rich cell wall

Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers.

Tritordeum, a hybrid cereal with a highly tricin-enriched lignin

The lignin from tritordeum straw, a hybrid cereal from crossbreeding of durum wheat and wild barley, was isolated and chemically characterized. Its composition and structure were studied by analytical pyrolysis (Py-GC/MS), nuclear magnetic resonance spectroscopy (NMR), Derivatization Followed by Reductive Cleavage (DFRC) method, and gel permeation chromatography (GPC). The data revealed an enrichment of guaiacyl (G) units (H:G:S of 3:61:36), which had a significant impact on the distribution of inter-unit linkages. The predominant linkages were the β–O–4′ alkyl-aryl ethers (78 % of all linkages), with substantial proportions of condensed linkages such as phenylcoumarans (11 %), resinols (4 %), spirodienones (4 %), and dibenzodioxocins (2 %). Moreover, DFRC revealed that tridordeum straw lignin was partly acylated at the γ-OH with both acetates and p-coumarates. Acetates were principally attached to G-units, whereas p-coumarates were predominantly attached to S-units. Furthermore, and more importantly, tritordeum lignin incorporates remarkable amounts of a valuable flavone, tricin, exceeding 30 g per kilogram of straw. Given the diverse industrial applications associated with this high-value molecule, tritordeum straw emerges as a promising and sustainable resource for its extraction.

Recent Updates on Jellyfish: Applications in Agro-based Biotechnology and Pharmaceutical Interests

Jellyfish are gelatinous sea creatures that belong to the subphylum Medusozoa of the phylum Cnidaria and are found on many beaches worldwide. Despite being considered a nuisance, jellyfish have many uses, such as being a source of high-value molecules such as collagen, gelatin, and protein hydrolysates and a source of high-protein food. Studies related to its availability, post-harvest applications, and need-based use in biomedicine are thrust research of analysis or investigation. Therefore, this review has been designed with all the latest information with a focus on applications of jellyfish in agro-based biotechnology and pharmaceutics. The review has been systematically arranged to present on the broader search platform for future research studies and possible need-based applications.

Boryl radical-mediated halogen-atom transfer (XAT) enables the Sonogashira-like alkynylation of alkyl halides.

Alkynes are a crucial class of materials with application across the wide range of chemical disciplines. The alkynylation of alkyl halides presents an ideal strategy for assembling these materials. Current methods rely on the intrinsic electrophilic nature of alkyl halides to couple with nucleophilic acetylenic systems, but these methods faces limitations in terms of applicability and generality. Herein, we introduce a different approach to alkynylation of alkyl halides that proceeds via radical intermediates and uses alkynyl sulfones as coupling partners. This strategy exploits the ability of amine-ligated boryl radicals to activate alkyl iodides and bromides through halogen-atom transfer (XAT). The resulting radicals then undergo a cascade of α-addition and β-fragmentation with the sulfone reagent, leading to the construction of C(sp3)-C(sp) bonds. The generality of the methodology has been demonstrated by its successful application in the alkynylation of complex and high-value molecules.

Extended polyene formation by a cryptic iterative polyketide synthase from Rhodococcus.

Many reactive intermediates leading to high value molecules are biosynthesised by multifunctional enzymes in Actinobacteria. Herein we report the workings of a cryptic iterative polyketide synthase (iPKS) from the marine microorganism Rhodococcus erythropolis PR4. The iPKS generates extended polyenes up to C22 nonaenes, preluding novel chemistry and biology.

Vanilla’s Chemistry

Among Orchidaceae, only vanilla (Vanilla planifolia Andr.) is farmed for human consumption. Mexico gave this plant to the world as a gift, and it has been utilized for many things over the years. This crop's characteristic perfume is not present in the green pod; instead, it develops during the curing process, which varies based on the nation and growing region. Flavor and scent are the two most prominent fragrant qualities that emerge from cured vanilla pods. Over time, vanillin has become indispensable for usage in the food, pharmaceutical, and cosmetic industries as well as in medicine. Owing to the expensive price of genuine vanilla, different methods have been used to create vanillin, which is the primary molecule present in vanilla extracts or concentrates made by employing microbial cultures in a variety of chemical and microbiological procedures. The vanilla industry is one of many agro-industries and industries that produce garbage. Since the composition of vanilla waste (residues or by-products) has not been well investigated, it offers an intriguing avenue for research and potential high-value molecule production.

Rhodophyta DNA Barcoding: Ribulose-1, 5-Bisphosphate Carboxylase Gene and Novel Universal Primers.

Red algae (Rhodophyta) are a heterogeneous group of marine algal species that have served as a source of high-value molecules, including antioxidants and scaffolds, for novel drug development. However, it is challenging to identify Rhodophytes through morphological features alone, and in most instances, that has been the prevailing approach to identification. Consequently, this study undertook the identification of red algae species in Kenton-on-Sea, South Africa, as a baseline for future research on red algae biodiversity and conservation. The identification was achieved by designing, analysing, and using a set of universal primers through DNA barcoding of the rbcL gene. The PCR products of the rbcL gene were sequenced, and 96% of the amplicons were successfully sequenced from this set and matched with sequences on BOLD, which led to these species being molecularly described. Amongst these species are medicinally essential species, such as Laurencia natalensis and Hypnea spinella, and potential cryptic species. This calls for further investigation into the biodiversity of the studied region. Meanwhile, the availability of these primers will ease the identification process of red algae species from other coastal regions.

Deposition precipitation derived Ni-Co active sites for enhanced dry reforming of methane performances

Dry reforming of methane (DRM) is one of the routes proposed to valorize the CO2 into high value molecules, such as syngas (H2 + CO) by its reaction with methane. Due to thermodynamic limitation this reaction takes place at high temperatures, above 650 °C and in a presence of a catalyst. Ni and Co based catalysts are used in DRM, as Ni is showing good activities and Co is improving the selectivity. As the distribution of these two active sites is the key in achieving high conversions and good stability towards deactivation. In this work, bimetallic nanoparticles with various ratios (total loading of 20 wt%) were supported SBA-15 via phyllosilicate precursors. The Ni-Co bimetallic nanoparticles are obtained by activation in hydrogen. Ni-Co based materials were completely characterized in calcined and reduced phase by XRD, N2-physisorption, TPR, TEM, XPS). Only Ni and/or Co phyllosilicates are obtained indifferent of the ratio used, the deposition precipitation method is resulting in high specific surfaces of 300 m2g−1. After the reduction at 700 °C Ni-Co NPs are obtained with sizes between 2 and 7 nm as showed by XRD, TPR with bimetallic distribution of 15Ni-5Co, 10NI-10Co and 5Ni-15Co within single NPs as analyzed by S/TEM-EDX mapping. The catalytic performances over DRM are showing the following tendency 20Ni-0Co = 15Ni-5Co > 10NI-10Co > 5Ni-15Co > 0Ni-20Co, while cobalt reach catalysts are rapidly deactivating after 2 h of reaction. Best results are showed by 15Ni-5Co with conversions of 74.5% and 79% for CH4 and CO2 respectively after 200 h of reaction. The spent catalyst showing only 29 wt% carbon and limited sintering with fewer Ni-Co NPs of ∼13 nm observed. Such unforeseen stability is associated to the presence NPs with the shell composed majority of Ni active sites and with some Co atoms within the NPs in 15/5 catalyst formulation as shown by XPS and S/TEM-EELS mapping.

Human blood lipid profiles after dietary supplementation of different omega 3 ethyl esters formulations

The validity of omega 3 fatty acids (ω3 FAs), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as dietary supplements has been widely proved. It’s well known in fact, that they protect against cardiovascular diseases, reduce the levels of triacylglycerides (TAGs) and cholesteryl esters (CEs) in blood, and have anti-inflammatory activity. For these reasons, in the last few years the production of dietary supplement containing ω3 has increased significantly. In this context, the possibility to obtain ω3 and other high value molecules from alternative sources as fish waste, in accordance with the principles of circular economy, becomes an enormous attractive. In addition, the opportunity of creating new products, with greater health benefits, represents an interesting challenge. The current study was focused on the extraction of ω3 fatty acids and peptides from tuna waste industry, to realize a new dietary supplement. To this purpose, a supercritical fluid extraction (SFE) method was developed to separate, isolate, and enrich the different fractions subsequently used to produce an innovative formulate. The obtained supplement was characterized in terms of fatty acids esterified ester (FAEE) composition by gas chromatography (GC) coupled to both flame ionization detection (FID) and mass spectrometry (MS), and content of heavy metals by inductively coupled plasma–mass spectrometry (ICP-MS).The effects of ω3 supplementation on metabolism and circulating lipid profiles was tested on 12 volunteers and assessed by GC-FID analysis of whole blood collected on paper support (Dried Blood Spot, DBS) at the beginning of the study and after thirty days. The results of plasma fatty acids levels after 30 days showed a significant decrease in the ω6/ω3 ratio, as well as the saturated/polyunsaturated fatty acids (SFA/PUFA) ratio, compared to subjects who took the ω3 ethyl esters unformulated. The novel formulated supplements proved to be extremely interesting and promising products, due to a significant increase in bioavailability, that makes it highly competitive in the current panorama of the nutraceutical industry.

Discovery of isoflavone phytoalexins in wheat reveals an alternative route to isoflavonoid biosynthesis.

Isoflavones are a group of phenolic compounds mostly restricted to plants of the legume family, where they mediate important interactions with plant-associated microbes, including in defense from pathogens and in nodulation. Their well-studied health promoting attributes have made them a prime target for metabolic engineering, both for bioproduction of isoflavones as high-value molecules, and in biofortification of food crops. A key gene in their biosynthesis, isoflavone synthase, was identified in legumes over two decades ago, but little is known about formation of isoflavones outside of this family. Here we identify a specialized wheat-specific isoflavone synthase, TaCYP71F53, which catalyzes a different reaction from the leguminous isoflavone synthases, thus revealing an alternative path to isoflavonoid biosynthesis and providing a non-transgenic route for engineering isoflavone production in wheat. TaCYP71F53 forms part of a biosynthetic gene cluster that produces a naringenin-derived O-methylated isoflavone, 5-hydroxy-2',4',7-trimethoxyisoflavone, triticein. Pathogen-induced production and in vitro antimicrobial activity of triticein suggest a defense-related role for this molecule in wheat. Genomic and metabolic analyses of wheat ancestral grasses further show that the triticein gene cluster was introduced into domesticated emmer wheat through natural hybridization ~9000 years ago, and encodes a pathogen-responsive metabolic pathway that is conserved in modern bread wheat varieties.

Traditional Medicine — A Gold Mine in the Treatment of Asthma

Asthma is one of the chronic respiratory disorder whose incidence and intensity is rising day by day. Globally, this devastating disease affects almost 300 million people. Since ancient times, various plants had already been identified as traditionally and utilized by medical practices for managing asthma in many countries. This goal of the article is to investigate and consolidate information on the ethnomedical applications, phytochemistry, and preparation techniques of frequently used medicinal herbs to treat asthma. With soaring efficiency, the search for new, high-value molecules continue, and there are still many medications with side effects that need to be identified. Phenolics, sterols, and terpenoids, which are a key class of phytoconstituents against asthma are only a few examples of the active compounds against asthma that may be found in medicinal plants. It is advised that further research is required to identify adverse effects, effectiveness, and safety, as well as other factors of anti-asthmatic herbs and standardize herbal treatments.

Co-culture of Kluyveromyces marxianus and Meyerozyma guilliermondii with In Situ Product Recovery of 2-Phenylethanol.

Production of 2-phenylethanol (2-PE) via Kluyveromyces marxianus is well-established. However, co-culture with other microbes in combination with in situ product recovery (ISPR) yields improved selectivity and volumetric productivity. Fermentation ofK. marxianus (MUCL 53775) with direct inclusion of absorptive polymer Hytrel3548 achieved ISPR, but accumulation of the byproduct phenylethyl acetate (PEA) was strongly favored. Co-culture of K. marxianus (MUCL 53775) with Meyerozyma guilliermondii (MUCL 28072) with ISPR limited PEA production, thereby improving the 2-PE selectivity from 13 to 90%, compared to a pure culture of K. marxianus (MUCL 53775) under similar conditions. This improved the volumetric productivity by 85% compared to 2-PE ISPR with a pure culture of K. marxianus. This is the first report of co-culture in a two-phase fermentation for 2-PE bioproduction and demonstrates that interactions between co-culture and ISPR techniques can modulate bioproduction between 2-PE and byproduct PEA, and this technique will be explored for other strain combinations and for other high-value molecules of interest.

Sustainable biosynthetic pathways to value-added bioproducts from hydroxycinnamic acids.

The biorefinery concept, in which biomass is utilized for the production of fuels and chemicals, emerges as an eco-friendly, cost-effective, and renewable alternative to petrochemical-based production. The hydroxycinnamic acid fraction of lignocellulosic biomass represents an untapped source of aromatic molecules that can be converted to numerous high-value products with industrial applications, including in the flavor and fragrance sector and pharmaceuticals. This review describes several biochemical pathways useful in the development of a biorefinery concept based on the biocatalytic conversion of the hydroxycinnamic acids ferulic, caffeic, and p-coumaric acid into high-value molecules. KEY POINTS: • The phenylpropanoids bioconversion pathways in the context of biorefineries • Description of pathways from hydroxycinnamic acids to high-value compounds • Metabolic engineering and synthetic biology advance hydroxycinnamic acid-based biorefineries.

Prospects of microalgae in nutraceuticals production with nanotechnology applications

Nutraceutical supplements provide health benefits, such as fulfilling the lack of nutrients in the human body or being utilized to treat or cure certain diseases. As the world population is growing, certain countries are experiencing food crisis challenges, causing natural foods are not sustainable to be used for nutraceutical production because it will require large-scale of food supply to produce enriched nutraceutics. The high demand for abundant nutritional compounds has made microalgae a reliable source as they can synthesize high-value molecules through photosynthetic activities. However, some microalgae species are limited in growth and unable to accumulate a significant amount of biomass due to several factors related to environmental conditions. Therefore, adding nanoparticles (NPs) as a photocatalyst is considered to enhance the yield rate of microalgae in an energy-saving and economical way. This review focuses on the composition of microalgal biomass for nutraceutical production, the health perspectives of nutritional compounds on humans, and the application of nanotechnology on microalgae for improved production and harvesting. The results obtained show that microalgal-based compounds indeed have better nutrients content than natural foods. However, nanotechnology must be further comprehended to make them non-hazardous and sustainable.