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2.
ACS Omega ; 7(49): 45197-45207, 2022 Dec 13.
Article in English | MEDLINE | ID: mdl-36530239

ABSTRACT

This research aimed to produce, on a multigram scale, a new class of non-toxic, halogen- and metal-free antifouling agents from the abundant lecithin byproducts of industrial soybean oil extraction. Three glycerophospholipid analogues were prepared by a facile methanolysis of crude soybean lecithins and a subsequent solvent-free O-alkylation: lysoglycerophosphocholines (LGPCs) and its ether derivatives O-alkyl lysoglycerophosphocholines (ALPCs). As efficient antiproliferative agents, LGPCs and ALPCs are an eco-friendly alternative to current commercial antifoulants which possess significant toxicity to aquatic life. In situ immersion tests of coated stainless-steel nets with previously incorporated automotive paint products, LGPCs and ALPCs (1-O-octadecyl-2-O-acyl-sn-glycero-3-phosphocholine, ALPC18, and 1-O-hexadecyl-2-O-acyl-sn-glycero-3-phosphocholine, ALPC16), in an aquaculture reservoir in SP-Brazil revealed significant growth inhibition against macrofouling species, especially the epibiotic golden mussel (Limnoperna fortunei), when compared with the control. These results promise a more sustainable and ecologically innocuous approach to combating the biofouling phenomenon and the deeply concerning dissemination of the golden mussel which has provoked an economic crisis in the energy and aquaculture sectors.

3.
RSC Adv ; 10(2): 1050-1054, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-35494454

ABSTRACT

A chemoselective route for the synthesis of 1-O-alkylglycerols chimyl (1), batyl (2), and selachyl (3) is reported. These compounds can be naturally isolated from shark liver oil and the skin of animals such as stingrays and chimeras and exhibit potential anti-fouling activity. The synthetic approach developed in this work included two distinct methods of preparation. The first was based on solvent-free reactions catalyzed by onium quaternary salts (N and P) and ionic liquids; the second methodology was based on a series of one-pot reactions.

4.
Mar Pollut Bull ; 137: 702-710, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30503487

ABSTRACT

The objective of this study is to propose the use of specific synthetic lipid as an active substance (biocide) in the control of harmful aquatic microorganisms, such as pathogens and non-indigenous species, transported in ships' ballast water. The biocide candidate, without metal or halogen components, was produced from a sub-product of the edible oil industry, the lecithin. Laboratory assays were conducted with phytoplankton, zooplankton, and marine bacteria to evaluate the efficiency of the biocide. The study also considers specific biocide's characteristics related to environmental risks, such as chemical composition, persistence, bioaccumulation, and toxicity. Results showed that, in the first 24 h of treatment, the biocide effectively reduced the concentration of the planktonic micro-organisms to very low levels. Additionally, a preliminary risk evaluation pointed that biocide candidate has a low residual toxicity, also a low potential for persistence and bioaccumulation in the environment.


Subject(s)
Disinfectants/pharmacology , Lipids/pharmacology , Water Purification/methods , Bacteria/drug effects , Phytoplankton/drug effects , Plankton/drug effects
5.
Mar Environ Res ; 142: 59-68, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30274716

ABSTRACT

Changes in environmental conditions can influence sponges and their holobionts. The present study investigated the effect of upwelling and anthropogenic pollution on the bioactivity of marine sponges, microbial communities and functional genes, and composition of their chemical compounds. The species Dysidea etheria, Darwinella sp., Hymeniacidon heliophila and Tedania ignis were collected from areas with distinct influence of upwelling and low anthropogenic impact and from areas without influence of upwelling but affected by sewage and the port. In most cases, the same sponge species collected from areas with distinct environmental conditions had a different chemical composition, antifouling activity, composition and diversity of associated microorganisms. Antimicrobial, quorum sensing inhibitory and anti-larval activities of sponge extracts were more pronounced in the area without upwelling showing higher level of anthropogenic pollution. This study suggests that upwelling and anthropogenic pollution affect the chemical activity and holobiome composition of sponges.


Subject(s)
Environment , Microbiota/drug effects , Porifera/microbiology , Water Pollutants/toxicity , Animals , Aquatic Organisms/chemistry , Aquatic Organisms/drug effects , Aquatic Organisms/microbiology , Porifera/chemistry , Porifera/drug effects
6.
Proc Natl Acad Sci U S A ; 114(30): 7975-7980, 2017 07 25.
Article in English | MEDLINE | ID: mdl-28696316

ABSTRACT

Here, we show a unique crop response to intraspecific interference, whereby neighboring sunflower plants in a row avoid each other by growing toward a more favorable light environment and collectively increase production per unit land area. In high-density stands, a given plant inclined toward one side of the interrow space, and the immediate neighbors inclined in the opposite direction. This process started early as an incipient inclination of pioneer plants, and the arrangement propagated gradually as a "wave" of alternate inclination that persisted until maturity. Measurements and experimental manipulation of light spectral composition indicate that these responses are mediated by changes in the red/far-red ratio of the light, which is perceived by phytochrome. Cellular automata simulations reproduced the patterns of stem inclination in field experiments, supporting the proposition of self-organization of stand structure. Under high crop population densities (10 and 14 plants per m2), as yet unachievable in commercial farms with current hybrids due to lodging and diseases, self-organized crops yielded between 19 and 47% more oil than crops forced to remain erect.


Subject(s)
Helianthus/metabolism , Helianthus/radiation effects , Sunflower Oil/metabolism , Biomass , Genotype , Helianthus/genetics , Light
7.
Oecologia ; 167(1): 141-8, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21384175

ABSTRACT

Woody plant encroachment of savanna ecosystems has been related to altered disturbance regimes, mainly fire suppression and herbivore exclusion. In contrast, neighbourhood interactions among resident and colonising woody species have received little attention, despite their likely influence on the pattern and rate of tree establishment. We examined how resident palm trees (Butia yatay) and established adults of two riparian forest tree species (Allophylus edulis and Sebastiania commersoniana) influenced seed arrival and seedling performance of the latter two species in a humid savanna of east-central Argentina. Seed traps and seedlings of both riparian species were placed in herbaceous openings, and beneath palm, conspecific and heterospecific adult trees in two unburned savanna patches, and were monitored for 2 years. Only seeds of the bird-dispersed Allophylus arrived in palm microsites, yet survival of Allophylus seedlings near adult palms was limited by animal damage through trampling and burrowing, a non-trophic mechanism of apparent competition. Seeds of both riparian species dispersed into conspecific microsites, although adult trees selectively reduced growth of conspecific seedlings, a pattern consistent with the "escape hypothesis". Further, survival of Sebastiania increased in the moister Allophylus microsites, suggesting a one-way facilitative interaction between woody colonisers. Our results indicate that dispersal facilitation by resident savanna trees may be critical to riparian species invasion after fire suppression. Distance-dependent effects of conspecific and heterospecific adult trees could contribute to shape the subsequent dynamics of woody seedling establishment. Overall, we show that indirect interactions can play a prominent role in savanna encroachment by non-resident woody species.


Subject(s)
Arecaceae/physiology , Ecosystem , Seedlings/physiology , Trees/physiology , Argentina , Euphorbiaceae/physiology , Geography , Rivers , Sapindaceae/physiology , Seed Dispersal , Species Specificity
8.
Proc Biol Sci ; 275(1637): 897-905, 2008 Apr 22.
Article in English | MEDLINE | ID: mdl-18198146

ABSTRACT

Persistence and ubiquity of vertically transmitted Neotyphodium endophytes in grass populations is puzzling because infected plants do not consistently exhibit increased fitness. Using an annual grass population model, we show that the problems for matching endophyte infection and mutualism are likely to arise from difficulties in detecting small mutualistic effects, variability in endophyte transmission efficiency and an apparent prevalence of non-equilibrium in the dynamics of infection. Although endophytes would ultimately persist only if the infection confers some fitness increase to the host plants, such an increase can be very small, as long as the transmission efficiency is sufficiently high. In addition, imperfect transmission limits effectively the equilibrium infection level if the infected plants exhibit small or large reproductive advantage. Under frequent natural conditions, the equilibrium infection level is very sensitive to small changes in transmission efficiency and host reproductive advantage, while convergence to such an equilibrium is slow. As a consequence, seed immigration and environmental fluctuation are likely to keep local infection levels away from equilibrium. Transient dynamics analysis suggests that, when driven by environmental fluctuation, infection frequency increases would often be larger than decreases. By contrast, when due to immigration, overrepresentation of infected individuals tends to vanish faster than equivalent overrepresentation of non-infected individuals.


Subject(s)
Fungi/physiology , Poaceae/microbiology , Symbiosis , Models, Biological , Time Factors
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