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Helicosporidium is a genus of nonphotosynthetic, green algae in the family Chlorellaceae, closely related to Prototheca. It is a known pathogen of invertebrates, and its occurrence in vertebrates has not been documented. A captive, 10-month-old, male, albino California kingsnake (Lampropeltis californiae) was submitted for necropsy. Gross examination revealed hemorrhagic laryngitis and a red mottled liver. Histologically, intravascular, intramonocytic/macrophagic and extracellular, eukaryotic organisms were observed in all tissues. These organisms stained positive with Grocott-Gomori methenamine silver and periodic acid-Schiff and were variably acid-fast and gram-positive. Ultrastructural analysis revealed approximately 4 µm vegetative multiplication forms and cysts with 3 parallel ovoid cells and a helically coiled filamentous cell. A polymerase chain reaction with primers targeting Prototheca, amplicon sequencing, and Bayesian phylogenetic analysis confirmed it clustered within Helicosporidium sp. with 100% posterior probability. The genus Helicosporidium was found to nest within the genus Prototheca, forming a clade with Prototheca wickerhamii with 80% posterior probability.

\nHighlightsTrebouxia microalgae have previously been mostly reported as lichen photobionts. However, in recent years, reports of their occurrence outside the lichen symbiosis has been more common. This study provides evidence of free-living Trebouxia species, as well as the re-evaluation of six strains from the Coimbra Collection of Algae (ACOI 1141, ACOI 1821, ACOI 2621, ACOI 2622, ACOI 2623 and ACOI 3426) obtained via micropipette single-cell isolation. The nuclear Internal Transcribed Spacer rDNA was sequenced to infer its phylogenetic position within Trebouxia genus. Strains ACOI 1141, ACOI 1821, ACOI 2621 and ACOI 3426 clustered in a large clade with a species-level lineage previously named as Trebouxia sp. A13. This lineage comprises sequences belonging to three previously described Trebouxia species: Trebouxia crenulata, Trebouxia arboricola and Trebouxia aggregata. Strain ACOI 2623 clustered with a species-level lineage not yet formally described, but previously detected and coded as Trebouxia sp. A19. ACOI 2622 separated into an independent clade distinct from all other sequences included in the dataset. This strain has not been previously identified as a species-level lineage in other studies, thus we code it as A60 and describe it as Trebouxia valentina sp. nov. based on morphological, ultrastructural, molecular and phylogenetic analyses. Our findings highlight the ability of these microalgae, typically associated with lichens, to thrive independently and expand our understanding of their biology and ecology. Free-living Trebouxia species were isolated and added to the ACOI.ACOI 2623 clustered with a species-level lineage not yet described.ACOI 2622 is here described as Trebouxia valentina sp. nov.Free-living Trebouxia species were isolated and added to the ACOI.ACOI 2623 clustered with a species-level lineage not yet described.ACOI 2622 is here described as Trebouxia valentina sp. nov. [ABSTRACT FROM AUTHOR]

Pseudomonas sp. strain Go58 isolated from the biofilm on a water plant possesses cyanobactericidal activity through its production of cyanobactericidal molecules, yet strain Go58 interestingly promotes the growth of the chlorophyte (Chlorophyta; green algae) Desmodesmus subspicatus. An in-depth chemical analysis of the culture broth revealed the production of indole-3-acetic acid, a well-known plant hormone, together with its atypical structural isomer, 3-(hydroxyacetyl)indole. Both these compounds similarly enhanced the growth of D. subspicatus but did not affect other microalgae, including cyanobacteria and a diatom. No synergistic activity was observed between the two compounds, indicating that they likely target the same molecular pathway. In the co-cultivation condition, production of these compounds by strain Go58 was not boosted but rather reduced. Application of these compounds or strain Go58 also fostered the growth of the water plant Lemna minor. These findings suggest that Pseudomonas sp. Go58 is able to establish a mutualistic relationship with host water plants by producing both plant hormones and cyanobactericidal molecules in return for a suitable habitat and nutrients. Although chlorophytes are not expected to be a primary target of the strain Go58, promoting the growth of non-harmful Chlorophyta could help mitigate harmful cyanobacterial bloom. [ABSTRACT FROM AUTHOR]

Background: Plastids are usually involved in photosynthesis, but the secondary loss of this function is a widespread phenomenon in various lineages of algae and plants. In addition to the loss of genes associated with photosynthesis, the plastid genomes of colorless algae are frequently reduced further. To understand the pathways of reductive evolution associated with the loss of photosynthesis, it is necessary to study a number of closely related strains. Prototheca, a chlorophyte genus of facultative pathogens, provides an excellent opportunity to study this process with its well-sampled array of diverse colorless strains. Results: We have sequenced the plastid genomes of 13 Prototheca strains and reconstructed a comprehensive phylogeny that reveals evolutionary patterns within the genus and among its closest relatives. Our phylogenomic analysis revealed three independent losses of photosynthesis among the Prototheca strains and varied protein-coding gene content in their ptDNA. Despite this diversity, all Prototheca strains retain the same key plastid functions. These include processes related to gene expression, as well as crucial roles in fatty acid and cysteine biosynthesis, and membrane transport. Conclusions: The retention of vestigial genomes in colorless plastids is typically associated with the biosynthesis of secondary metabolites. In contrast, the remarkable conservation of plastid membrane transport system components in the nonphotosynthetic genera Prototheca and Helicosporidium provides an additional constraint against the loss of ptDNA in this lineage. Furthermore, these genes can potentially serve as targets for therapeutic intervention, indicating their importance beyond the evolutionary context. [ABSTRACT FROM AUTHOR]

Biological invasions are a major threat for many aquatic ecosystems. In contrast to higher plants and animals, microbial invasions are less obvious and more difficult to detect. One of the most prominent microbial invaders is the cyanobacterium Raphidiopsis raciborskii. To better understand the environmental conditions favoring its invasion success, we studied invasion under three different temperature regimes (one constant and two variable) in experimental plankton communities by invader addition experiments. To account for intraspecific variation, we tested four different strains of R. raciborskii and the mixture of them. Invasion success of R. raciborskii was higher under constant temperature conditions than under fluctuations suggesting that the resident species responded faster to the environmental changes than the invaders. We observed a clear strain‐specific effect, demonstrating that strain identity is an important determinant of invasion success. The interaction of temperature fluctuations and strain identity indicates that, among the tested strains, the response to the temperature regimes varied. The mixture of all four strains did not perform better than the best single strain showing no sign of a positive genetic diversity effect. In our experiment, environmental fluctuations did not widen a window of opportunity for the invasion of R. raciborskii. [ABSTRACT FROM AUTHOR]

In this study two types of marine algae: red algae (Callithamnion corymbosum – CC-RAB) and green algae (Ulva lactuca – UL-GAB), were used for the retention of Cu2+, Zn2+ and Co2+ ions from aqueous media, by biosorption. Both types of marine algae are abundant on the Romanian coast of the Black Sea and, since they have no uses, they represent a serious problem for the beach area. Therefore, their use as biosorbents for the recovery of some metal ions of strategic industrial importance (such as Cu2+, Zn2+ and Co2+ ions) may represent a way to valorise this biomass resource. In order to evaluate the biosorptive performances of the red algae biomass (CC-RAB) and green algae biomass (UL-GAB), batch experimental studies were carried out at different initial solution pH, biosorbent dose, initial metal ions concentration contact time and temperature. The optimal conditions (pH = 5.0; 2.0 g biosorbent L-1, 3 h, 25 ±1 °C) were then used to obtain kinetic curves and biosorption isotherms, which were modelled. The pseudo-second order kinetic model best fits the kinetic data, while the biosorption isotherms are described by the Langmuir model, for all studied metal ions on both biosorbents. The maximum biosorption capacity depends on the nature of algae biosorbent, and follows the order: Cu2+ (81.25 mg g-1) > Zn2+ (73.69 mg g-1) > Co2+ (27.89 mg g-1) in the case of CC-RAB, and Zn2+ (69.29 mg g-1) > Cu2+ (43.47 mg g-1) > Co2+ (26.15 mg g-1) in the case of UL-GAB. The thermodynamic parameters (∆G0, ∆H0 and ∆S0) were also evaluated, and the obtained values indicate that all biosorption processes are spontaneous and endothermic. In addition, desorption of metal ions is quantitative in acid media, but the biosorption capacities decrease significantly after the first cycle of use. All these aspects have important environmental implications, and may provide benchmarks in the design of a strategy for the valorisation of this biomass resource. [ABSTRACT FROM AUTHOR]

Sulfated polysaccharides derived from green marine macroalgae are known for their wide range of therapeutic properties, including the mitigation of inflammatory disorders. A sulfated polysaccharide, URP-2, composed of (1 → 4) linked α-rhamnopyranose, β-xylopyranose, and β-glucuropyranose, was isolated from Ulva reticulata (Ulvaceae). URP-2 exhibited significant anti-inflammatory effects by increasing interferon (IFN)-α expression (four to ten-fold) in lipopolysaccharide (LPS)-induced CALU-1 cells in a dose-dependent manner (31.25 to 125 μg mL−1), compared to LPS-induced cells. Additionally, the elevated IFN-γ levels observed in LPS-induced cells were substantially reduced (by five-fold) following treatment with URP-2 at 125 μg mL−1. URP-2, at a concentration of 125 μg mL−1, effectively reduced the elevated levels of interleukin (IL)-1β in LPS-induced cells, decreasing it from approximately 95% to 1.3%. Tumor necrosis factor (TNF)-α level was also reduced from 30% to approximately 1% in LPS induced CALU-1 cells. Structure–activity relationship analyses of URP-2 suggest that its potent anti-inflammatory properties are likely attributed to the presence of sulfate groups and (1 → 4) linkages. Therefore, URP-2 demonstrated promising potential as a natural alternative for the treatment of inflammatory-related disorders. [ABSTRACT FROM AUTHOR]

Genus Ulva is commercially exploited for diverse potential, emerging and established applications ranging from food, animal feed, aqua feed, plant bio-stimulant, bioenergy, and biomedical applications of its polysaccharide. This study aims to investigate the effects of Ascophyllum Marine Plant Extract Powder (AMPEP) at different concentrations (0.01, 0.05, 0.1 and 0.5 %) and times (15, 30, and 60 min) on the growth, physiology, and biochemical composition of the green seaweed Ulva ohnoi. Treatment with 0.5% AMPEP for 30 minutes significantly increased ratio of divided and undivided cells on day-4 (6.43 ± 2.36). Additionally, a 1.2-fold enhancement in gross primary productivity (GPP), chlorophyll-a, -b, and total chlorophyll content indicated an overall improvement in photosynthetic efficiency. The levels of carotenoids and auxins showed 2.1 and 6.4-fold increases, respectively. Similarly, a 1.4 and 1.2-fold rise in total carbohydrate content and antioxidant capacity was observed. Moreover, antioxidant enzymes, catalase (CAT), glutathione reductase (GR), and superoxide dismutase (SOD) were significantly elevated in the AMPEP-treated thallus, underscoring the improved stress tolerance and metabolic vigour of the treated plants. To the best of our knowledge, this is the first-ever study on the effect of AMPEP on green seaweed Ulva. This bio-stimulatory effect would undoubtedly be helpful in enhancing the growth and yield of Ulva in tank and multi-tubular airlift photobioreactor-based cultivation protocol. [ABSTRACT FROM AUTHOR]

Over recent years consumer preference has shifted towards natural-based products, prompting the food, cosmetic, and pharmaceutical industries to explore new natural sources. Algae, particularly seaweeds like Caulerpa racemosa, have emerged as promising candidates due to their nutritional richness and bioactive compounds. This review comprehensively examines the nutritional profile of C. racemosa, covering its carbohydrates, fibers, proteins, amino acids, minerals, lipids, vitamins, and pigments. The alga is rich in bioactive metabolites, including terpenoids, alkaloids, sterols, and other secondary metabolites, which contribute to its health-promoting properties. The potential health benefits of C. racemosa are extensive, including antihypertensive, anti-hyperlipidaemic, antibacterial, antimicrobial, anti-cancer, anti-diabetic, anti-hyperglycaemic, anti-inflammatory, and antioxidant activities. Special emphasis is placed on its antioxidant properties, detailing the total phenol content (TPC), total flavonoid content (TFC), and the overall antioxidant capacity. Additionally, the tyrosinase inhibitory activity of C. racemosa suggests its potential in cosmetic applications. Despite its promising health and industrial uses, the standardization of C. racemosa products remains a challenge due to variability in active compound concentrations. This review underscores the multifaceted benefits of C. racemosa, advocating for its broader utilization in health, nutrition, and cosmetics, highlighting the need for further in-depth studies to fully realize its potential. [ABSTRACT FROM AUTHOR]

Photosystem I (PSI) serves as a model system for studying fundamental processes such as electron transfer (ET) and energy conversion, which are not only central to photosynthesis but also have broader implications for bioenergy production and biomimetic device design. In this study, we employed electron paramagnetic resonance (EPR) spectroscopy to investigate key light-induced charge separation steps in PSI isolated from several green algal and cyanobacterial species. Following photoexcitation, rapid sequential ET occurs through either of two quasi-symmetric branches of donor/acceptor cofactors embedded within the protein core, termed the A and B branches. Using high-frequency (130 GHz) time-resolved EPR (TR-EPR) and deuteration techniques to enhance spectral resolution, we observed that at low temperatures prokaryotic PSI exhibits reversible ET in the A branch and irreversible ET in the B branch, while PSI from eukaryotic counterparts displays either reversible ET in both branches or exclusively in the B branch. Furthermore, we observed a notable correlation between low-temperature charge separation to the terminal [4Fe-4S] clusters of PSI, termed FA and FB, as reflected in the measured FA/FB ratio. These findings enhance our understanding of the mechanistic diversity of PSI's ET across different species and underscore the importance of experimental design in resolving these differences. Though further research is necessary to elucidate the underlying mechanisms and the evolutionary significance of these variations in PSI charge separation, this study sets the stage for future investigations into the complex interplay between protein structure, ET pathways, and the environmental adaptations of photosynthetic organisms.

Energy status and nutrients regulate photosynthetic protein expression. The unicellular green alga Chromochloris zofingiensis switches off photosynthesis in the presence of exogenous glucose (+Glc) in a process that depends on hexokinase (HXK1). Here, we show that this response requires that cells lack sufficient iron (-Fe). Cells grown in -Fe+Glc accumulate triacylglycerol (TAG) while losing photosynthesis and thylakoid membranes. However, cells with an iron supplement (+Fe+Glc) maintain photosynthesis and thylakoids while still accumulating TAG. Proteomic analysis shows that known photosynthetic proteins are most depleted in heterotrophy, alongside hundreds of uncharacterized, conserved proteins. Photosynthesis repression is associated with enzyme and transporter regulation that redirects iron resources to (a) respiratory instead of photosynthetic complexes and (b) a ferredoxin-dependent desaturase pathway supporting TAG accumulation rather than thylakoid lipid synthesis. Combining insights from diverse organisms from green algae to vascular plants, we show how iron and trophic constraints on metabolism aid gene discovery for photosynthesis and biofuel production.

Marine algae are central to global carbon fixation, and their productivity is dictated largely by resource availability. Reduced nutrient availability is predicted for vast oceanic regions as an outcome of climate change; however, there is much to learn regarding response mechanisms of the tiny picoplankton that thrive in these environments, especially eukaryotic phytoplankton. Here, we investigate responses of the picoeukaryote Micromonas commoda, a green alga found throughout subtropical and tropical oceans. Under shifting phosphate availability scenarios, transcriptomic analyses revealed altered expression of transfer RNA modification enzymes and biased codon usage of transcripts more abundant during phosphate-limiting versus phosphate-replete conditions, consistent with the role of transfer RNA modifications in regulating codon recognition. To associate the observed shift in the expression of the transfer RNA modification enzyme complement with the transfer RNAs encoded by M. commoda, we also determined the transfer RNA repertoire of this alga revealing potential targets of the modification enzymes. Codon usage bias was particularly pronounced in transcripts encoding proteins with direct roles in managing phosphate limitation and photosystem-associated proteins that have ill-characterized putative functions in "light stress." The observed codon usage bias corresponds to a proposed stress response mechanism in which the interplay between stress-induced changes in transfer RNA modifications and skewed codon usage in certain essential response genes drives preferential translation of the encoded proteins. Collectively, we expose a potential underlying mechanism for achieving growth under enhanced nutrient limitation that extends beyond the catalog of up- or downregulated protein-encoding genes to the cell biological controls that underpin acclimation to changing environmental conditions.

Recently, scientists have been interested in developing advanced techniques for technological applications using sustainable biochar (BC) materials. In this study, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, PEDOT/PSS, was doped with 5 wt.% and 10 wt.% of Activated biochar (A-BC) obtained from Chlorophyta (green Algae) using a microwave combustion process. XRD, FTIR, TGA, BET, and SEM were used to analyze the structural properties of PEDOT/PSS@BC. The XRD results demonstrate that A-BC impacts the amorphous nature of PEDOT/PSS, causing the doped composite to have a higher crystalline structure. While measuring dark current density-voltage, it was found that PEDOT/PSS@BC/n-Si showed better-rectifying characteristics compared to pristine PEDOT/PSS/n-Si, with a higher rectification ratio. When A-BC was used, the power conversion efficiency (PCE) was 13.02%, with a short circuit current density (Jsc) of 34.37 mA/cm2, open-circuit voltage (Voc) of 0.65 V, and fill factor (FF) of 58%. These findings demonstrated that using A-BC improved the characteristics of PEDOT/PSS/n-Si devices, and the increase in performance was affected by the concentration of A-BC. A-BC can act as an efficient electron acceptor, facilitating charge transfer and reducing recombination losses.

A number of advancements have been made in algal technology in different fields, such as medical, cosmetic, and pharmaceutical. Green algae (Chlorophyta) are a group of photosynthetic organisms which live in both aquatic and terrestrial environments. They are a potential source of bioactive compounds for the treatment and prevention of a wide range of infectious diseases caused by microorganisms. These compounds also possess anti-inflammatory, antioxidant, anticoagulant, antitumor, and immunomodulatory properties. A wide variety of bioactive compounds are produced, including polysaccharides, which exhibit antimicrobial properties capable of interfering with the cell walls, membranes, and nucleic acids of microorganisms. Membrane fluidity, permeability, or integrity can be affected by polyphenols and fatty acids which scavenge free radicals, chelate metal ions, or disrupt enzymes and membranes. Proteins and peptides form pores within the membranes which bind to specific receptors or inhibit enzymes. Adaptation to adverse environmental conditions, such as temperature extremes, photooxidation, salinity, or osmotic stress, results in the formation of bioactive compounds by altering the physiological and biochemical pathways of algae for the maintenance of cellular homeostasis. With changing consumer preferences and an increase in the number of resistant microorganisms, it is critical to seek novel antimicrobial compounds from green algae. The search for novel bioactive compounds with antimicrobial properties from green algae may serve as an alternative in the light of increased drug resistance in microorganisms. However, in vitro and in vivo evaluations of the safety, efficacy, and mechanism of action of the antimicrobial compounds from green algae require more research. Providing an overview of previous endeavours in this emerging field, this review provides perspectives and a summary of the bioactive compounds responsible for the antimicrobial properties of green algal extracts.

We studied the microbial diversity colonizing limestone rock pools at a Neolithic Monument (Arbor Low, Derbyshire, England). Five pools were analyzed: four located at the megaliths of the stone circle and one pool placed at the megalith at the Gib Hill burial mound 300 m distant. Samples were taken from rock pool walls and sediments, and investigated through molecular metabarcoding. The microbiome consisted of 23 phyla of bacteria (831 OTUs), 4 phyla of archaea (19 OTUs), and 27 phyla of microbial eukarya (596 OTUs). For bacteria, there were statistically significant differences in wall versus sediment populations, but not between pools. For archaea and eukarya, significant differences were found only between pools. The most abundant bacterial phylum in walls was Cyanobacteriota, and Pseudomonadota in sediments. For archaea and microbial eukarya, the dominant phyla were Euryarcheota and Chlorophyta, respectively, in both wall and sediments. The distant pool (P5) showed a markedly different community structure in phyla and species, habitat discrimination, and CHN content. Species sorting and dispersal limitation are discussed as mechanisms structuring the microbiome assemblages and their spatial connectivity. The Arbor Low microbiome is composed of terrestrial representatives common in extreme environments. The high presence of Cyanobacteriota and Chlorophyta in the Arbor Low stones is troubling, as these microorganisms can induce mechanical disruption by penetrating the limestone matrix through endolithic/chasmoendolithic growth. Future research should focus on the metabolic traits of strains to ascertain their implication in bioweathering and/or biomineralization. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is an emerging organic compound used in the production of epoxy resin, polycarbonate plastics and thermal paper. Following the restrictions on the use of bisphenol A, many substitutes have been produced as its replacement in several consumer products. The main task of this research was to examine the toxic effects of single bisphenol analogues and their mixtures against freshwater microalgae Chlorella vulgaris and Desmodesmus armatus. The findings suggest that bisphenol B, bisphenol C, bisphenol PH (EC50 (14 day): 33.32-43.32 mg L-1) and bisphenol B, bisphenol C, bisphenol FL, bisphenol PH (EC50 (14 day): 30.49-64.54 mg L-1) show strong toxic effects towards C. vulgaris and D. armatus, respectively. In turn, the research results indicate that the toxicity of a mixture of examined bisphenol analogs on both species of green algae is much higher (EC50 (14 day): 24.55-32.68 mg L-1) than the individual toxicity of each component of the mixture. Therefore, it can be concluded that mixtures lead to the occurrence of synergistic effects. The toxicity of the individual bisphenol analogues and their mixture by EC50 (14 day) values in descending order, was as follows: mixture>bisphenol PH> bisphenol B> bisphenol C> bisphenol FL> bisphenol F> bisphenol E for C. vulgaris and bisphenol B> mixture> bisphenol FL> bisphenol C> bisphenol PH> bisphenol E> bisphenol F for D. armatus, respectively. Moreover, the present research expands current knowledge of the ecotoxicological risks of bisphenol analogues to aquatic organisms. [ABSTRACT FROM AUTHOR]

Photoautotrophic algal cultivation is challenging due to the shadowing effect produced by an increase in the number of cells; under such circumstances, mixotrophic growth might be an efficient alternative. We grew cultures of the autochthonous acidotolerant microalga Elliptochloris sp. on crude technical glycerin or glucose bubbled with either only air or air containing 2.5 % (v/v) CO2. We found that CO2 strongly influenced the production of Elliptochloris sp., as higher growth occurred in mixotrophy with CO2-enriched air compared to that with only air. Mixotrophy with CO2-enriched air allowed to reach higher biomass productivities and facilitated an increase in the relative abundance of saturated fatty acids. Nevertheless, mixotrophy with only air resulted in an increase of both saturated and unsaturated fatty acids, but biomass productivities were lower. These results, along with the limited biological contamination facilitated by low pH, suggest that this microalga might be attractive for large-scale production within the circular economy model. [ABSTRACT FROM AUTHOR]

The present study investigated the impact of seasonal variation on biomass availability, proximate composition, fatty acid profile, minerals content, pigments, moisture content, and elemental composition of an edible green alga Gayralia brasiliensis collected from Shirgaon estuary Maharashtra, west coast of India. Additionally, the physico-chemical parameters of the Shirgaon estuary were analyzed and correlated with biomass abundance and biochemical composition of G. brasiliensis. The findings of the present study demonstrated a significant variation in the physico-chemical parameters of seawater throughout the seasons. During the summer season, the biomass abundance (258.23 ± 23.06 g m-2 FW), and the total protein content (11.12 ±1.37 % DW) were found highest while the total lipid content declined considerably. Nonetheless, the contents n-6 and n-3 PUFA increased significantly over the winter season. The concentration of micro-elements was highest during the winter season while the macro-elements found plenty during the monsoon season. The correlogram analysis revealed that biomass, total protein, total carbohydrate, chlorophyll pigments, and tissue C, H, N, and S were positively correlated with each other throughout all three seasons. Based on Pearson corelation analysis it is confirmed that among the environmental parameters, irradiance and temperature were found the most limiting factors for the growth of G. brasiliensis. Further, dissolved inorganic nitrate significantly influence the growth of G. brasiliensis negatively. Overall, the results of this study imply that G. brasiliensis should be harvested for desired metabolites during the respective seasons. The findings of the present study are expected to be extremely valuable for future cultivation strategies and edible applications of G. brasiliensis in India. [ABSTRACT FROM AUTHOR]

The deficiency in the worldwide protein provision from marine capture fisheries has led the Malaysian government to reevaluate its aquaculture approach, prioritising three commodities: seaweed, fish, and marine shrimp. However, comprehensive documentation of the performance of the Malaysian aquaculture sector, particularly in seaweed production, is lacking. Caulerpa (Chlorophyta), a seaweed genus abundantly available in Malaysia, holds the potential to emerge as a primary alternative food source in the future. This paper offers an overview of Caulerpa aquaculture, specifically focusing on C. lentillifera and C. racemosa, covering aspects such as taxonomy, phytomorphology, geographical distribution and habitat, cultivation system, chemical composition, pharmacological properties, and future prospects for sustainable aquaculture. Although the cultivation system has been implemented on a small scale in various districts in Malaysia, it is anticipated to escalate production and productivity due to the substantial demand for Caulerpa spp. both domestically and globally. The cultivation of Caulerpa spp. in Malaysia, in alignment with the National Agrofood Policy 2021–2030 (NAP 2.0), signals a trajectory toward enhancing the nation's food security in aquaculture and meeting the economic requirements for seaweed production. [ABSTRACT FROM AUTHOR]

To thrive on melting alpine and polar snow, some Chlorophytes produce an abundance of astaxanthin, causing red blooms, often dominated by genus Sanguina. The red cells have not been cultured, but we recently grew a green biciliate conspecific with Sanguina aurantia from a sample of watermelon snow. This culture provided source material for Oxford Nanopore Technology and Illumina sequencing. Our assembly pipeline exemplifies the value of a hybrid long- and short-read approach for the complexities of working with a culture grown from a field sample. Using bioinformatic tools, we separated assembled contigs into 2 genomic pools based on a difference in GC content (57.5 and 55.1%). We present the data as 2 assemblies of S. aurantia variants but explore other possibilities. High-throughput chromatin conformation capture analysis (Hi-C sequencing) was used to scaffold the assemblies into a 96-Mb genome designated as "A" and a 102-Mb genome designated as "B." Both assemblies are highly contiguous: genome A consists of 38 scaffolds with an N50 of 5.4 Mb, while genome B has 50 scaffolds with an N50 of 6.4 Mb. RNA sequencing was used to improve gene annotation. [ABSTRACT FROM AUTHOR]

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Abstract Polar marine macroalgae thrive in extreme conditions, often displaying geographic isolation and high degree of endemism. The “phycosphere” refers to the zone around the algae inhabited by microrganisms. Our study used DNA metabarcoding to survey the eukaryotic communities associated with seven seaweed species obtained at King George Island (South Shetland Islands, maritime Antarctic), including two Rhodophyta, two Chlorophyta and three Phaeophyceae. The ITS2 region was used as a barcode and our analysis yielded 77 eukaryotic ASVs spanning five Kingdoms (Fungi, Metazoa, Chromista, Protozoa, and Viridiplantae) and ten phyla (Ascomycota, Basidiomycota, Cercozoa, Ciliophora, Ochrophyta, Amebozoa, Chlorophyta, Rhodophyta, Bryophyta and Cnidaria). Additionally, we identified 14 potential new occurrence records for Antarctica. Ciliates and green algae were the most species-rich groups. The most abundant assigned associated species was Monostroma angicava (Chrorophyta). Within the macroalgal, the Chlorophyceans Ulothrix sp. hosted the greatest number of taxa, followed by Monostroma hariotii. Our data suggested that Antarctic macroalgae host a rich diversity of associated organisms and the biodiversity associated with the phycosphere remains underestimated.

Abstract The complex interactions between epiphytic bacteria and marine macroalgae are still poorly understood, with limited knowledge about their community structure, interactions, and functions. This study focuses on comparing epiphytic prokaryotes community structure between three seaweed phyla; Chlorophyta, Rhodophyta, and Heterokontophyta in an easternmost rocky intertidal site of the Mediterranean Sea. By taking a snapshot approach and simultaneously collecting seaweed samples from the same habitat, we minimize environmental variations that could affect epiphytic bacterial assembly, thereby emphasizing host specificity. Through 16S rRNA gene amplicon sequencing, we identified that the microbial community composition was more similar within the same seaweed phylum host compared to seaweed host from other phyla. Furthermore, exclusive Amplicon Sequence Variants (ASVs) were identified for each algal phyla despite sharing higher taxonomic classifications across the other phyla. Analysis of niche breadth indices uncovers distinctive affinities and potential specialization among seaweed host phyla, with 39% of all ASVs identified as phylum specialists and 13% as generalists. Using taxonomy function prediction, we observed that the taxonomic variability does not significantly impact functional redundancy, suggesting resilience to disturbance. The study concludes that epiphytic bacteria composition is connected to host taxonomy, possibly influenced by shared morphological and chemical traits among genetically related hosts, implying a potential coevolutionary relationship between specific bacteria and their host seaweeds.

The complex interactions between epiphytic bacteria and marine macroalgae are still poorly understood, with limited knowledge about their community structure, interactions, and functions. This study focuses on comparing epiphytic prokaryotes community structure between three seaweed phyla; Chlorophyta, Rhodophyta, and Heterokontophyta in an easternmost rocky intertidal site of the Mediterranean Sea. By taking a snapshot approach and simultaneously collecting seaweed samples from the same habitat, we minimize environmental variations that could affect epiphytic bacterial assembly, thereby emphasizing host specificity. Through 16S rRNA gene amplicon sequencing, we identified that the microbial community composition was more similar within the same seaweed phylum host compared to seaweed host from other phyla. Furthermore, exclusive Amplicon Sequence Variants (ASVs) were identified for each algal phyla despite sharing higher taxonomic classifications across the other phyla. Analysis of niche breadth indices uncovers distinctive affinities and potential specialization among seaweed host phyla, with 39% of all ASVs identified as phylum specialists and 13% as generalists. Using taxonomy function prediction, we observed that the taxonomic variability does not significantly impact functional redundancy, suggesting resilience to disturbance. The study concludes that epiphytic bacteria composition is connected to host taxonomy, possibly influenced by shared morphological and chemical traits among genetically related hosts, implying a potential coevolutionary relationship between specific bacteria and their host seaweeds. [ABSTRACT FROM AUTHOR]

The unceasing rise in human population has provoked large environmental damage, essentially in air and water habitats. Microalgae have been deeply investigated regarding wastewater treatment as well as a suitable biofuel feedstock. Nevertheless, process optimization and the search for new local strains are imperative to overcome the cost-effectiveness bottleneck that persist in large-scale technology. Linked to this, micro-diversity studies in landfill leachates have been done. However, there has been no study which analysed specifically the microalgal diversity outside of this less-explored environment to see their biotechnological potential. Hence, a specific study of microalgal diversity present in leachates produced by a non-hazardous waste landfill (mainly for municipal solid waste MSW) located in Asturias (Spain) was done. The new strain Chlorella vulgaris DSAF was isolated and identified based on both morphological and molecular methods. Some parameters based on site-climate conditions were studied to understand C. vulgaris DSAF behaviour. The modification in the lipid content and FAMEs profile in response to the stress caused by the addition of NaCl and nutrient deprivation were also studied. The stress induction produced significant morphological changes when compared to control group (e.g., bigger cell sizes). Specifically, the addition of 25 g L-1 of NaCl achieved an increase of 25% of biomass. Total lipids increased under nutrient deprivation (N, P and NP) from 13 to 34% (w/w). Oleic acid was the most abundant fatty acid, reaching 50% of total FAMEs under NP deprivation conditions. Linoleic acid and α-linolenic acid also showed a moderate increase during NaCl stress. The positive results during calculation of the main biodiesel properties determined that C. vulgaris DSAF would be a potential biodiesel feedstock under different cultivation conditions. [ABSTRACT FROM AUTHOR]

The marine prasinophyte green algae Pycnococcus provasolii and Pseudoscourfieldia marina represent the only extant genera and known species of the Pycnococcaceae. However, their taxonomic status needs to be reassessed, owing to the very close relationship inferred from previous sequence comparisons of individual genes. Although Py. provasolii and Ps. marina are morphologically different, their plastid rbcL and nuclear small subunit rRNA genes were observed to be nearly or entirely identical in sequence, thus leading to the hypothesis that they represent distinct growth forms or alternate life‐cycle stages of the same organism. To evaluate this hypothesis, we used organelle genomes as molecular markers. The plastome and mitogenome of Ps. marina UIO 007 were sequenced and compared with those available for two isolates of Py. provasolii (CCMP 1203 and CCAP 190/2). The Ps. marina organelle genomes proved to be almost identical in size and had the same gene content and gene order as their Py. provasolii counterparts. Single nucleotide substitutions and insertions/deletions were localized using genome‐scale sequence alignments. Over 99.70% sequence identities were observed in all pairwise comparisons of plastomes and mitogenomes. Alignments of both organelle genomes revealed that Ps. marina UIO 007 is closer to Py. provasolii CCAP 190/2 than are the two Py. provasolii strains to one another. Therefore, our results are not consistent with the placement of Ps. marina and Py. provasolii strains into distinct genera. We propose a taxonomic revision of the Pycnococcaceae and the erection of a new class of Chlorophyta, the Pseudoscourfieldiophyceae. [ABSTRACT FROM AUTHOR]

This paper presents the first data on the biodiversity of lithophytic algae from Bulgarian megaliths obtained after the application of the direct sampling method, subsequent cultivation, and processing by light microscopy. A rich algal flora was found: 90 species and 1 variety of 65 genera from Cyanoprokaryota/Cyanobacteria (29 species, 13 genera), Chlorophyta (40 species and 1 variety, 38 genera), Streptophyta (5 species, 1 genus), and Ochrophyta (16 species, 13 genera). Among them were the globally rare Pseudodictyochloris multinucleata (Chlorophyta), found for the first time in such lowland and warm habitats, and Scotiella tuberculata (Chlorophyta), for which this is the first finding in the country. Three of the recorded species are conservationally important. The low floristic similarity between the sites (0–33%) shows the diversity of the algal flora, with no common species found for all the megaliths studied. The most widespread were the strongly adaptive and competitive Stichococcus bacillaris, Apatococcus lobatus, and Chloroidium ellipsoidium (Chlorophyta). The correlations estimated between the species number and substrate temperature (18.1–49.6 °C) suggest the prospect of future research related to the impact of global warming. In addition, the study points to the safety aspects as it revealed species from nine potentially toxin-producing cyanoprokaryotic genera that could be harmful to visitors' health. [ABSTRACT FROM AUTHOR]

Polar regions harbor a diversity of cold-adapted (cryophilic) algae, which can be categorized into psychrophilic (obligate cryophilic) and cryotrophic (nonobligate cryophilic) snow algae. Both can accumulate significant biomasses on glacier and snow habitats and play major roles in global climate dynamics. Despite their significance, genomic studies on these organisms remain scarce, hindering our understanding of their evolutionary history and adaptive mechanisms in the face of climate change. Here, we present the draft genome assembly and annotation of the psychrophilic snow algal strain CCCryo 101-99 (cf. Sphaerocystis sp.). The draft haploid genome assembly is 122.5 Mb in length and is represented by 664 contigs with an N50 of 0.86 Mb, a Benchmarking Universal Single-Copy Orthologs (BUSCO) completeness of 92.9% (n = 1,519), a maximum contig length of 5.3 Mb, and a guanine-cystosine (GC) content of 53.1%. In total, 28.98% of the genome (35.5 Mb) contains repetitive elements. We identified 417 noncoding RNAs and annotated the chloroplast genome. The predicted proteome comprises 14,805 genes with a BUSCO completeness of 97.8%. Our preliminary analyses reveal a genome with a higher repeat content compared with mesophilic chlorophyte relatives, alongside enrichment in gene families associated with photosynthesis and flagella functions. Our current data will facilitate future comparative studies, improving our understanding of the likely response of polar algae to a warming climate as well as their evolutionary trajectories in permanently cold environments. [ABSTRACT FROM AUTHOR]

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AbstractThis study focuses on the sustainable synthesis of Mn3O4 nanoparticles using Chlorophyta seaweed extracts for electrochemical capacitor applications. X-ray diffraction (XRD), ultraviolet-visible (UV–Visible) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transform infrared (FTIR) spectroscopy were used to evaluate the produced nanoparticles to determine their crystallinity, structure, shape, and elemental composition. The XRD results showed diffraction peaks that correspond to the Hausmannite Mn3O4 phase, with a 24.4 nm-sized average crystallite. The electrochemical properties were examined through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). When compared to a bare Ni electrode, the electrochemical analysis showed a voltammetric response that was 17-fold higher. For the kinetics of the electrochemical reaction, the charge transfer coefficient (αa) and apparent electron transfer rate constant (ks) were determined to be 4.0 s−1 and 0.33, respectively. The diffusion coefficient, as evaluated using the Randles-Sevcik equation, was 1.78 × 10−6 cm2/s. The analysis conducted at various scan rates revealed a diffusive contribution of 90.6% at 5 mV/s and 67.7% at 100 mV/s. In contrast, at a scan rate of 100 mV/s, the capacitive contribution increased from 9.4 to 32.3%. The change in the time for the interaction between ions and electrode material is responsible for the reduction in the diffusive component and the increase in the capacitive component. [ABSTRACT FROM AUTHOR]

The microalga Monoraphidium sp. QLY-1 is considered to have potential as a lipid feedstock for biodiesel. However, the large-scale use of microalgae lipids is limited by difficulties in biomass harvesting and high costs. Among the many microalgae harvesting methods, chemical flocculation is considered to be a suitable method for large-scale harvesting. In this study, the effects of five inorganic flocculants (ferric chloride, ferric sulfate, aluminum sulfate, magnesium hydroxide and alum) and two organic polymeric flocculants, polyacrylamide (PAM) and polydiallyldimethylammoniumchloride (PDADMAC), on the flocculation efficiency of Monoraphidium sp. QLY-1 and the cost of flocculants were analyzed. The flocculation efficiency of Monoraphidium sp. QLY-1 was unsatisfactory when treated with ferric chloride, magnesium hydroxide, alum or PAM (all less than 90% in 4 h). However, iron sulfate, aluminum sulfate and PDADMAC significantly promoted the flocculation efficiency of Monoraphidium sp. QLY-1 (all above 90% in a short settling time). PDADMAC could be used as an ideal flocculant for large-scale harvesting of Monoraphidium sp. QLY-1 due to its high flocculation efficiency (92.90% ± 0.92 in 1 h with 40 mg L-1) and low cost of use (microalgal broth m-3 with an estimated cost of 0.039 US$). [ABSTRACT FROM AUTHOR]

Caulerpa macrodisca and Caulerpa lentillifera, green macroalgae consumed as fresh salads in Malaysian communities esteemed for their robust nutritional profile, were investigated for their viability in dried seaweed sheet production. This study comprehensively analyzed the proximate composition and amino acid content of both species before incorporating them into dried seaweed sheet formulations. An organoleptic test, involving 50 diverse panellists, evaluated characteristics such as appearance, aroma, texture, taste, colour, and overall satisfaction. Three formulations, denoted as sample A (50% C. lentillifera and 50% C. macrodisca), sample B (100% C. lentillifera), and sample C (100% C. macrodisca), were created, and compared with a commercially available dried seaweed sheet (Sample D). The proximate analysis revealed that C. lentillifera contained 12.47±0.06% moisture, 39.18±0.29% ash, 1.76±0.09% crude lipid, 11.35±0.24% crude protein, 23.99±0.95% crude fiber, and 35.24±0.59% carbohydrate, while C. macrodisca exhibited 8.99±0.25% moisture, 34.14±1.65% ash, 0.78±0.09% crude lipid, 21.51±0.44% crude protein, 19.70±0.82% crude fiber, and 34.57±2.12% carbohydrate. Amino acid analysis identified 16 amino acids, with phenylalanine being the highest for both species (C. lentillifera: 16.54±1.41 mg g-1, C. macrodisca: 20.96±0.27 mg g-1). The organoleptic test indicated that sample A achieved the highest overall satisfaction and texture scores, whereas sample C excelled in taste characteristics. Sample B received the lowest scores across all attributes. Consequently, this study suggests that the dried seaweed sheet formulated with a combination of both species (sample A) is favoured by most panellists, demonstrating its potential for commercialization as a wholesome and appealing snack. [ABSTRACT FROM AUTHOR]

The green microalga Monoraphidium sp. has potential for biodiesel production since it grows fast and can accumulate high levels of lipids. However, there is a lack of information on the potential use in human nutrition. In this work Monoraphidium sp. was characterized in terms of macronutrients with a special focus on the fatty acid profile of the lipid fraction and on the amino acid profile of the proteins. Furthermore, aiming at nutrient valorization, various methods for lipid extraction that could be used in the production of high quality and safe foods were investigated. To this end, the focus was on cell disruption methods in order to optimize oil recovery. The Monoraphidium sp. biomass had a high protein concentration (44.5 %) and a relatively low lipid concentration (12.5 %) but was rich in ω-3 fatty acids demonstrating its high nutritive value. Regarding cell disruption, ultrasonication and high-speed homogenization were insufficient to disrupt cells under the conditions examined. On the other hand, the effectiveness of the ball milling was regulated via processing time and water-to-biomass ratio and complete cell disruption could be achieved by this method. For lipid extraction, solvent extraction using a mixture of food-grade hexane and ethanol resulted in an oil recovery of 70.4 %, whereas using ethanol alone as an environmentally friendly solvent resulted in an oil recovery equal to 54 %. Supercritical CO2 extraction resulted in a lower oil recovery (25 %), whereas ethanol addition, as a cosolvent to CO2, significantly increased the oil recovery (60 %). [ABSTRACT FROM AUTHOR]

Cultivation of microalgae has gained significant interest as an alternative protein source, potentially becoming a target commodity recovered from microalgae-based wastewater treatment. This study examined a semi-continuous cultivation strategy to optimize protein accumulation of the indigenous freshwater chlorophytes, Lobochlamys segnis and Klebsormidium flaccidum, and simultaneously remove nutrients from wastewater efficiently. A strain-specific regime was made based on a fixed biomass concentration at the start of 24-h cultivation cycle, i.e., a constant initial cell density, which regulated harvesting and fresh medium supply volume according to the dilution rate. Six cultivation cycles were conducted in lab-scale 1L reactors with a synthetic municipal wastewater. Lobochlamys segnis and K. flaccidum grew exponentially in all cycles. The biomass productivity was 573 and 580 mg L–1 day–1, in which the total protein consisted of 62 and 45% of dry cell weight (dw), respectively. When a culture medium deficient in nitrogen and phosphorus was used, protein level was significantly reduced. L. segnis consumed all NH4+ and PO43– supplied by the medium replacement, giving the removal rate of 9.2 and 5.2 mg L–1 day–1. Whereas K. flaccidum removed 13.8 mg L–1 day–1 NH4+ without completing PO43– removal. The amino acid profile of both strains was characterized by glutamic acids content (4–5% dw). We concluded that the designed cultivation regime would support a constant biomass production with stable and high protein content, along with an efficient removal of nutrient from the wastewater. [ABSTRACT FROM AUTHOR]

Our study aims to investigate the water quality and distribution patterns of phytoplankton communities in the Jinjiang River Basin in Quanzhou, as well as their relationship with environmental factors. We integrated data from the national water quality databases of the two main tributaries of the West and East Jinjiang Rivers between 2020 and 2023, supplemented by field surveys. Redundancy analysis was used to explore the effect of environmental factors on phytoplankton communities. Our findings revealed that the West Jinjiang River experienced a significant influence from excessive fertilizer use in tea cultivation, leading to an increase in TN concentrations compared to the East Jinjiang River. The abundance of phytoplankton in the Jinjiang River Basin was 105 cells·L−1, with phytoplankton being dominated by Chlorophyta, Cyanphyta, and diatoms, accounting for an average of 50%, 20%, and 19% of the total phytoplankton abundance, respectively. Redundancy analysis indicated that temperature, pH, and nutrient concentrations were important factors influencing the phytoplankton communities. With increasing temperature and nutrients concentrations, the abundance of Chlorophyta and Dinophyta significantly increased. This study provides a solid foundation for the regular "health diagnosis" of crucial rivers and lakes in Quanzhou and supports the establishment of a health guarantee system for rivers and lakes. [ABSTRACT FROM AUTHOR]

AbstractTropical reef communities contain spatial patterns at multiple scales, observable from microscope and satellite alike. Many of the smaller-scale patterns are generated physiologically (e.g., skeletal structures of corals at

Effective monitoring of non-indigenous seaweeds and combatting their effects relies on a solid confirmation of the non-indigenous status of the respective species. We critically analysed the status of presumed non-indigenous seaweed species reported from the Mediterranean Sea, the Northeast Atlantic Ocean and Macaronesia, resulting in a list of 140 species whose non-indigenous nature is undisputed. For an additional 87 species it is unclear if they are native or non-indigenous (cryptogenic species) or their identity requires confirmation (data deficient species). We discuss the factors underlying both taxonomic and biogeographic uncertainties and outline recommendations to reduce uncertainty about the non-indigenous status of seaweeds. Our dataset consisted of over 19,000 distribution records, half of which can be attributed to only five species (Sargassum muticum, Bonnemaisonia hamifera, Asparagopsis armata, Caulerpa cylindracea and Colpomenia peregrina), while 56 species (40%) are recorded no more than once or twice. In addition, our analyses revealed considerable variation in the diversity of non-indigenous species between the geographic regions. The Eastern Mediterranean Sea is home to the largest fraction of non-indigenous seaweed species, the majority of which have a Red Sea or Indo-Pacific origin and have entered the Mediterranean Sea mostly via the Suez Canal. Non-indigenous seaweeds with native ranges situated in the Northwest Pacific make up a large fraction of the total in the Western Mediterranean Sea, Lusitania and Northern Europe, followed by non-indigenous species with a presumed Australasian origin. Uncertainty remains, however, regarding the native range of a substantial fraction of non-indigenous seaweeds in the study area. In so far as analyses of first detections can serve as a proxy for the introduction rate of non-indigenous seaweeds, these do not reveal a decrease in the introduction rate, indicating that the current measures and policies are insufficient to battle the introduction and spread of non-indigenous species in the study area. Non-indigenous seaweed species in the Northeast Atlantic Ocean, the Mediterranean Sea and Macaronesia are critically reanalysed. > 19,000 distribution records revealed considerable variation in diversity of non-indigenous seaweed species in the study area. Taxonomic and biogeographic uncertainties hamper a critical evaluation of the non-indigenous status of many seaweed species. [ABSTRACT FROM AUTHOR]

Caulerpa lentillifera, known as 'sea grapes´ or 'green caviar´, is increasingly in demand as a sea vegetable for human consumption. The seaweed is cultivated in ponds in the Khánh Hòa province in Van Phong Bay, Viet Nam, during the dry season (March-October). The harvested sea grape fronds are graded into different qualities based on their physical characteristics for retail on the local market or for export. Based on systematic observations of sea grape fronds of two different qualities, the frond weight, frond length and rachis coloration were identified as physical characteristics important for grading. Fronds of the best quality had significantly longer (12.59 ± 2.89 vs 10.01 ± 2.51 cm) and heavier (2.37 ± 0.59 vs 1.60 ± 0.5 g) fronds with darker rachis than the other quality group. However, a logistic regression model revealed that frond weight was the best predictor of frond quality. The physiological parameter of Fv/Fm was slightly different between the qualities, but always with means > 0.7, whereas the antioxidant activity and the total phenolic content were similar (98.34 ± 19.22 vs 95.96 ± 24.98 mmol TE (100 g)−1 DW and 163.8 ± 20.14 vs 149.85 ± 15.44 mg GAE (100 g)−1 DW). To the best of our knowledge, this study took a first approach to identify quality characteristics of sea grape fronds from Van Phong Bay, Viet Nam, which can serve as a basis for adjusting cultivation parameters to improve the harvest quality by developing cultivation and post-harvest protocols. However, further research is needed to investigate the effect of certain cultivation parameters on the specific frond characteristics. [ABSTRACT FROM AUTHOR]

This study was carried out to develop a protocol for the biomass production and cultivation of Ulva ohnoi using germling clusters. The zygote germination was evaluated under different density conditions (10, 20, 30, and 40 × 104 gametes mL−1), nutrients (4, 8, and 16 mL L−1 of von Stosch standard solution), and irradiance (100, 200, and 300 μmol photons m−2 s−1). Afterwards, the formed germling clusters were cultivated in two pulse-fed treatments, one with nutrients offered once and the other on a daily basis, to establish a growth curve and evaluate the limiting factors. Once the optimal conditions for the cultivation were established, they will be evaluated for mature fronds based on the growth rate and productivity. Irradiance was the main factor that affected germling development. Moreover, the nutrient concentration did not present differences in their development. Germling clusters, at low densities had a significantly higher growth rate. Nutrient treatments with 8 mL L−1 was sufficient for the growth of germling clusters. The maximum cultivation period under the conditions tested was four days and thereafter the nutrients and density become limiting, and the renewal of the culture medium, harvest, and return to the initial density is recommended. Germling clusters are preferable over adult fronds, as they showed more significantly stable growth rates and yields, while adult fronds started to reproduce causing reduced growth and productivity. [ABSTRACT FROM AUTHOR]