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Light Spectra, a Promising Tool to Modulate Ulva lacinulata Productivity and Composition
No full textLight quality is a key factor affecting algal growth and biomass composition, particularly
pigments such as carotenoids, known for their antioxidant properties. Light-emitting diodes (LEDs)
are becoming a cost-effective solution for indoor seaweed production when compared to fluorescent
bulbs, allowing full control of the light spectra. However, knowledge of its effects on Ulva biomass
production is still scarce. In this study, we investigated the effects of LEDs on the phenotype of an
Ulva lacinulata strain, collected on the Northern Portuguese coast. Effects of white (W), green (G), red
(R), and blue (B) LEDs were evaluated for growth (fresh weight and area), photosynthetic activity,
sporulation, and content of pigments and antioxidant compounds. The results showed that there
were no significant differences in terms of fresh weight accumulation and reduced sporulation among
the tested LEDs, whileWlight induced the highest expansion rate. Under G, U. lacinulata attained
a quicker photoacclimation, and the highest content of pigments and total antioxidant activity; but
with R andW, antioxidant compounds against the specific radicals O2
?? and ?NO were produced
in a higher content when compared to other LEDs. Altogether, this study demonstrated that it is
possible to modulate the bioactive properties of U. lacinulata by using W, R, and G light, opening the
path to the production of biomass tailored for specific nutraceutical applications
Integration of Tetraselmis chuii and Artemia sp. Culture in Industrial-Scale Salt Production
No full textThe common technique of traditional salt production in Indonesia is seawater evaporation technology, which uses sunlight to produce salt crystals from seawater. However, in general, the applied technology only produces salt with about 80% NaCl and water contents >7%, impurities >2%, and other contaminants. This produced salt is not suitable to be used as industrial salt. This study aimed to determine the effects of liquid organic fertilizer Gracilaria sp. addition into the culture media of Tetraselmis chuii on Artemia sp. growth, to identify the profile of length, weight, and survival rate of Artemia sp., and finally attempted to uncover the contribution of Artemia sp. in impurity mineral absorption and NaCl content improvement. The results of the study showed that the density of T. chuii based on the concentration of liquid organic fertilizer Gracilaria sp. was significantly different (p0.05) on the weight and length gain of Artemia sp. The research conducted can support the downstream use of products from engineering research in the field of technology to increase the added value of salt products and be part of the contribution to the achievement of the 14th SDG on life below water
Exploring the effects of temperature and light availability on the vegetative propagation processes of the non-native species Asparagopsis armata
No full textWidespread generalist species, particularly the non-native invasive ones, are
expected to be enhanced by climate change resulting in a biotic
homogenization of ecosystems. The red seaweed Asparagopsis armata is a
non-native opportunistic species, widely distributed in the European coasts of
the North Atlantic, where it has been considered invasive. In this work, we
examined the effects of temperature and irradiance on the vegetative
propagation process of this species in a laboratory experiment. We considered
vegetative propagation due to its implications in the invasion process (as it is
considered one of the main sources of recruitment). In gametophytes, the
process was characterized through the survival rates of hook-shaped
specialized structures and the production and growth of new plantlets from
hooks of 1-3cm in length. In tetrasporophytes, the growth and phycobiliprotein
contents of previously excised tufts was analyzed. For gametophytes, results
revealed how vegetative propagation for this species was conditioned by the low
survival rates of hooks once detached from the main thallus. In our experiment,
survival probabilities after 30 days of culture were always below 50%.
Comparisons among environmental conditions showed lower survival rates
under increasing levels of temperature and decreasing levels of irradiance. In
fact, mass mortality was detected at 18?C and low irradiance, where almost any
hook-shaped fragment survived. Nevertheless, patterns of appearance and
growth of plantlets at different temperatures and irradiances were not clear. In
the case of tetrasporophytes, only positive growth rates were registered at 15?C
and 55-60 ?mol/m2/s after 30 days of culture. Higher concentration of
phycobiliproteins was detected at higher temperatures during the first days of
culture, while not clear patterns were detected at the end. In the light of climate
change, understanding these reproduction patterns is necessary in order to
adopt better management actions in the future.
KEYWORD
Chaetomorpha linum Extract as a Source of Antimicrobial Compounds: A Circular Bioeconomy Approach
No full textThe circular bioeconomy is currently a promising model for repurposing natural sources;
these sources include plants due to their abundance of bioactive compounds. This study evaluated the
antimicrobial properties of a Chaetomorpha linum extract. Chaetomorpha linum is an invasive macroalga
from the Orbetello Lagoon (Tuscany, Italy), which grows in nutrient-rich environments and has been
forming extended mats since 2005. The biomass is mechanically harvested and treated as waste,
consuming considerable manpower and financial resources. As a potential way to increase the value
of such waste, this study found that C. linum extract (CLE) is a source of antimicrobial compounds.
The phytochemical characterization of the extract revealed the predominant presence of palmitic acid,
a fatty acid with known antimicrobial activity. Based on such findings, four bacterial species of high
clinical relevance (Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia
coli) were tested, revealing a notable antibacterial activity of the extract on Enterococcus faecalis (MIC,
32 ?g/mL). Computational analyses identified a potential Enterococcus faecalis molecular target for
palmitic acid, offering molecular insights on the interaction. This study presents a comprehensive
in vitro and in silico approach for drug and target discovery studies by repurposing C. linum as a
source of antimicrobial bioactive compounds
PALM KERNEL EXPELLER (PKE) SEBAGAI MAKANAN UNTUK Artemia: KESAN KEPADA TUMBESARAN, BIOJISIM DAN POPULASI MIKROB SEMASA PENGKULTURAN DALAM TANGKI
No full textConnectivity between populations of the scallop Pecten maximus in the Irish Sea and the implications for fisheries management
No full textMarine species with a pelagic larval phase have the potential to disperse
hundreds of kilometres via ocean currents, thus connecting geographically
distinct populations. Connectivity between populations therefore plays a
central role in population dynamics, genetic diversity and resilience to
exploitation or decline and can be an important vector in the management of
fisheries. The scallop, Pecten maximus, is a valuable benthic bivalve with a variety
of management measures at both regional and national scales. A bio-physical
numerical model was developed to simulate and characterise the larval
transport and population connectivity of scallops across commercial fishing
grounds within the Irish and Celtic Seas. The model incorporated realistic
oceanographic currents and known behavioural traits of P. maximus larvae
including spawning times, pelagic larval duration, and vertical migration during
the various developmental stages i.e., passive, active swimming, vertical
migrations, since growth rates change with temperature, which varies spatially
and temporally, it was used in the model to determine when an individual larva
changed its behaviour. Simulation
APPLICATION OF LOOP-MEDIATED ISOTHERMAL AMPLIFICATION FOR Edwardsiella ictaluri DETECTION IN INDONESIA ENTERIC SEPTICEMIA OF CATFISH
No full textLoop-mediated isothermal amplification (LAMP) method is useful for
rapidly detecting Edwardsiella ictalurid infection, especially enteric
septicemia of catfish (ESC). This study aims to investigate the LAMP method
for E. ictaluri detection in ESC. This research was an experimental study
using a total of 55 catfish, consisting of 5 negative controls and 50 catfish
injected intraperitoneally with 0.1 mL of E. ictaluri at a concentration of
105 CFU/mL. The kidneys of three fishes were randomly selected 6, 12, 18,
24, 30, 36, 42, 48, and 54 hours after infection with E. ictaluri. In addition,
samples were also collected on days 3, 5, and 7. Bacterial analysis was
determined by conventional biochemistry (genus and species test), wholegenome
sequencing of catfish, and LAMP amplification. All types of data
obtained in this study were analyzed by descriptive statistics to compare
infected and healthy catfish. The catfish were infected with E. ictaluri
after 12 hours of infection according to the LAMP amplification procedure
which revealed hemorrhages throughout the body, fins, protruding
eyes, necrosis, inflammation of the spleen, liver, intestine, pale gills, gut,
abdomen swelling, and tissue necrosis in the upper part of the head. It
can be concluded that the LAMP method is more effective than the PCR
method for detecting infection with E. ictaluri in catfish
Challenges to Seagrass Restoration in the Indian River Lagoon, Florida
No full textSeagrasses provide valuable ecosystem services, including improved water quality, carbon
sequestration, and sediment stabilization. Unfortunately, these critical habitats are declining globally
due to a range of anthropogenic impacts. Restoration practitioners have made efforts to mitigate
loss through the introduction of seagrass transplants. However, seagrass restoration has low success
rates and is plagued by water quality concerns and ecosystem degradation. Studies to improve
seagrass restoration efforts have targeted different functional taxa to allow for greater stability and
recovery of threatened ecosystems, and excluded macro-grazers to limit losses to newly established
and restored seagrasses. We hypothesized greater seagrass (Halodule wrightii) health when restored
in conjunction with hard clams (Mercenaria mercenaria) and protected from grazers using herbivore
exclusion devices (HEDs) in the Indian River Lagoon (IRL), Florida. While our study experienced
high rates of seagrass mortality, we were able to observe significant differences in seagrass health
between IRL sub-lagoons and observed the positive effects of HEDs on seagrass health. The observed
high species mortality highlights how restoration in the IRL is hindered by biotic and abiotic stressors,
site selection, and a lack of clear restoration protocols. As we see ongoing declines in water quality
and loss of foundational species, informed site selection, greater understanding of grazer presence,
and multi-species restoration will provide an informed approach for future seagrass restoration
projects globally
A Characterization of the RNA Modification Response to Starvation under Low Temperatures in Large Yellow Croaker (Larimichthys crocea)
No full textEmerging evidence shows that N6-methyladenosine (m6A) is a post-transcriptional RNA
modification that plays a vital role in regulation of gene expression, fundamental biological processes,
and physiological functions. To explore the effect of starvation on m6A methylation modification in
the liver of Larimichthys crocea (L. crocea) under low temperatures, the livers of L. crocea from cold and
cold + fasting groups were subjected to MeRIP-seq and RNA-seq using the NovaSeq 6000 platform.
Compared to the cryogenic group, the expression of RNA methyltransferases mettl3 and mettl14 was
upregulated, whereas that of demethylase fto and alkbh5 was downregulated in the starved cryogenic
group. A Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that
the differentially m6A-modified genes were mainly enriched in steroid biosynthesis, DNA replication,
ribosome biogenesis in eukaryotes, PPAR, ECM-receptor interaction, lysine degradation,
phosphatidylinositol, and the MAPK signaling pathway, suggesting that L. crocea responds to starvation
under low-temperature stress through m6A methylation modification-mediated cell growth,
proliferation, innate immunity, and the maintenance of lipid homeostasis. This study advances
understanding of the physiological response mechanism exerted by m6A methylation modification
in starved L. crocea at low temperatures
Exploring the Internal Defense System of Cerastoderma glaucum (Brugui?re, 1789) Exposed to Pristine Microplastics: The Sentinel Role of Haemocytes as Biomarkers
No full textThe ubiquitous presence of microplastics (MPs) in the environment is a major concern for
the conservation of biodiversity. Numerous studies show the detrimental effects of MPs on marine
species, especially because of their small size and their capacity to absorb organic contaminants from
their surroundings. The bivalve mollusk Cerastoderma glaucum (Brugui?re, 1789), because of its wide
geographic distribution and immobile feeding habits, can be used as a sentinel and bioindicator
species. By examining the presence, localization, and co-localization of Toll-like receptor 2 (TLR2)
and inducible nitric oxide synthetase (iNOS), this study aims to evaluate the response of the internal
defense system of C. glaucum to pristine MPs through the employment of confocal microscopy and
bioinformatics techniques. The results show haemocytes immunoreactive to the antibodies tested; in
particular, a higher number of TLR2-positive haemocytes can be observed in the group exposed to
pristine MPs. These findings suggest that haemocytes can play a key biomarker role as sentinels to
environmental pollutants. Furthermore, bioinformatics analyses on the antibodies tested confirmed
an evolutionary conservation of these molecules. These data highlight the critical role of phagocytosis
in identifying ecosystem damage and are helpful in developing biosensors with less negative effects
on the environments in which they are applied