Microalgae and Cyanobacteria Strains as Producers of Lipids with Antibacterial and Antibiofilm Activity

Abstract

Lipids are one of the primary metabolites of microalgae and cyanobacteria, which enrich their utility in the pharmaceutical, feed, cosmetic, and chemistry sectors. This work describes the isolation, structural elucidation, and the antibiotic and antibiofilm activities of diverse lipids produced by different microalgae and cyanobacteria strains from two European collections (ACOI and LEGE-CC). Three microalgae strains and one cyanobacteria strain were selected for their antibacterial and/or antibiofilm activity after the screening of about 600 strains carried out under the NoMorFilm European project. The total organic extracts were firstly fractionated using solid phase extraction methods, and the minimum inhibitory concentration and minimal biofilm inhibitory concentration against an array of human pathogens were determined. The isolation was carried out by bioassay-guided HPLC-DAD purification, and the structure of the isolated molecules responsible for the observed activities was determined by HPLC-HRESIMS and NMR methods. Sulfoquinovosyldiacylglycerol, monogalactosylmonoacylglycerol, sulfoquinovosylmonoacylglycerol, α-linolenic acid, hexadeca-4,7,10,13-tetraenoic acid (HDTA), palmitoleic acid, and lysophosphatidylcholine were found among the different active sub-fractions selected. In conclusion, cyanobacteria and microalgae produce a great variety of lipids with antibiotic and antibiofilm activity against the most important pathogens causing severe infections in humans. The use of these lipids in clinical treatments alone or in combination with antibiotics may provide an alternative to the current treatments.

Microalgae Bioactive Compounds to Topical Applications Products—A Review

“…Similarly, a study by Mukherjee et al [ 55 ] with the hexane and chloroform extracts from Scenedesmus obliquus , tested in both Gram-positive and Gram-negative bacteria, showed the highest antibacterial activity with a minimum inhibitory concentration (MIC) of 15.6–125 μg·mL −1 . In the same line with previous works, Cepas et al [ 56 ] utilized lipids from over 600 microalgae and cyanobacteria species to determine their activities as antimicrobials and antibiofilms. The authors found that the extracts were effective against one of the three bacterial strains tested, whereas the assayed extracts from the methanol and ethyl acetate fraction reached an 80% biofilm inhibition.…”

Health benefits of microalgae and their microbiomes

“…In addition, both C. vulgaris and Tetradesmus obliquus had comparatively high levels of 18:1 fatty acids as well as 18:3, linolenic acid (Chac on-Lee and Gonz alez-Mariño, 2010). This is in accordance with the reports of Cepas et al (2021) who, after screening the fatty acid profiles of several strains of cyanobacteria also reported that C. vulgaris and T. obliquus were particularly rich in linolenic acid.…”

“…This is in accordance with the reports of Cepas et al . ( 2021 ) who, after screening the fatty acid profiles of several strains of cyanobacteria also reported that C. vulgaris and T. obliquus were particularly rich in linolenic acid.…”

Synthesis of the cyanobacterial halometabolite Chlorosphaerolactylate B and demonstration of its antimicrobial effect in vitro and in vivo

“…Herein we confirmed that Cyanobacteria (photosynthetic prokaryotes) represent a source for identification of new types of halogenated compounds with antimicrobial properties, i.e., halogenated fatty acids. A recent study demonstrated that microalgae and cyanobacteria produce a great variety of different lipids with antibiotic and antibiofilm activity against the most important pathogens causing severe infections in humans ( Cepas et al, 2021 ). In conclusion, the cyanobacterial halometabolite Chlorosphaerolactylate B can be synthesized, and the synthetic compound shows antibacterial and antibiofilm activity.…”

“…Recently, 600 strains of microalgae and cyanobacteria were screened for antibiofilm and/or antibacterial activity carried out under the European H2020 project named NOMORFILM (Novel marine biomolecules against biofilm. Application to medical devices) ( Cepas et al, 2021 ). In that project, a new halometabolite family of chlorinated lactylates named Chlorosphaerolactylates A–D was isolated from a methanolic extract of the cyanobacterium Sphaerospermopsis sp.…”