Lipids of Marine Algae—Biomolecules with High Nutritional Value and Important Bioactive Properties

Marine microalgae are a multitude of taxonomically diverse unicellular organisms, ranging from diatoms to dinoflagellates and several other well-known groups, that may dwell in the water column, occur in marine sediments, or even associate symbiotically with marine animals.

Taxonomy and Ecology of Marine Algae

The term “algae” refers to a large diversity of unrelated phylogenetic entities, ranging from picoplanktonic cells to macroalgal kelps [...]

Toxicity of environmentally important micropollutants on three trophic levels

Micropollution is a serious environmental problem caused by continuous entry of trace quantities of toxic chemical substances into the aquatic environment. In the present study, three trophic levels of the aquatic ecosystems were used to evaluate the acute toxicities of environmentally important micropollutants including heavy metals, pesticides and drugs. There is a scarcity of information on toxicity of the studied substances on marine water algae. Among studied micropollutants, the most toxic chemical to Daphnia magna and Danio rerio was found to be 1-Chloro-2,4 dinitrobenzene with EC50 of 0.002 and 4.2 mg/L, respectively. Although this compound was also toxic to marine algae, Phaeodactylum tricornutum, arsenic showed the highest toxicity to the algae with EC50 of 2.4 mg/L. As compared to other organisms, D. magna was found to have higher sensitivity to all of the tested micropollutants.

IN MEMORY OF VERA BORISOVNA VOZZHINSKAYA

On July 29, 2021, just 90 years have passed since the day of birth of Vera Borisovna Vozzhinskaya, doctor of biological sciences, head of the Laboratory of biological foundation of mariculture IO RAS. She was connected with our Institute during all her life, 43 years – from young post-graduate up to well-known algologist, specialist in benthic marine algae. She was a bright personality, outstanding organizer, skilled expedition worker. Under her leadership 37 coastal expeditions of IO were carried out – to the White, Barents, Black and Far East Seas. She tragically perished in happy and long-awaited moment: just after the authorization of her degree (doctor of biology) by All-Russian Attestation Commission. Publications by V.B. Vozzhinskaya are in demand up to now, especially her unique monograph on the White Sea macrophytobenthos and investigations on productivity of bottom seaweeds.

Genome Sequence of Chrysotila roscoffensis, a Coccolithphore Contributed to Global Biogeochemical Cycles

Chrysotila is a genus of coccolithophores. Together with Emiliania, it is one of the representative genera in the Haptophyta which have been extensively studied. They are photosynthetic unicellular marine algae sharing the common characteristic of the production of CaCO3 platelets (coccoliths) on the surface of their cells and are crucial contributors to global biogeochemical cycles. Here, we report the genome assembly of Chrysotila roscoffensis. The assembled genome size was ~636 Mb distributed across 769 scaffolds with N50 of 1.63 Mb, and maximum contig length of ~2.6 Mb. Repetitive elements accounted for approximately 59% of the genome. A total of 23,341 genes were predicted from C. roscoffensis genome. The divergence time between C. roscoffensis and Emiliania huxleyi was estimated to be around 537.6 Mya. Gene families related to cytoskeleton, cellular motility and morphology, and ion transport were expanded. The genome of C. roscoffensis will provide a foundation for understanding the genetic and phenotypic diversification and calcification mechanisms of coccolithophores.

Revisiting marine bioprospecting of tropical Indonesian macroalgae from West Timor

<p>Marine algae are an important and historically rich source of new marine-based natural products. This thesis describes the screening of 40 Indonesian macroalgal samples using liquid chromatography-mass spectrometry (LC-MS) based molecular networking, and the subsequent nuclear magnetic resonance (NMR)-guided isolation and structural elucidation of a 6-deoxy-6-aminoglycoglyrecolipid (60). Molecular networking was performed using LC-MS/MS data through the online Global Natural Product Social Molecular Networking (GNPS) platform directly from crude extracts. NMR spectroscopy-guided screening was also employed targeting unique peaks detected by 1H NMR to validate any hits from GNPS. Out of 40 macroalgae specimens collected from West Timor waters, six samples were prioritised by the molecular networking screening. Proton NMR revealed three specimens with significantly interesting peaks but only one specimen, Laurencia snackeyi was purified further, which yielded compound 60.</p>

Revisiting marine bioprospecting of tropical Indonesian macroalgae from West Timor

<p>Marine algae are an important and historically rich source of new marine-based natural products. This thesis describes the screening of 40 Indonesian macroalgal samples using liquid chromatography-mass spectrometry (LC-MS) based molecular networking, and the subsequent nuclear magnetic resonance (NMR)-guided isolation and structural elucidation of a 6-deoxy-6-aminoglycoglyrecolipid (60). Molecular networking was performed using LC-MS/MS data through the online Global Natural Product Social Molecular Networking (GNPS) platform directly from crude extracts. NMR spectroscopy-guided screening was also employed targeting unique peaks detected by 1H NMR to validate any hits from GNPS. Out of 40 macroalgae specimens collected from West Timor waters, six samples were prioritised by the molecular networking screening. Proton NMR revealed three specimens with significantly interesting peaks but only one specimen, Laurencia snackeyi was purified further, which yielded compound 60.</p>

Dietary Enteromorpha Polysaccharide Enhances Intestinal Immune Response, Integrity, and Caecal Microbial Activity of Broiler Chickens

Marine algae polysaccharides have been shown to regulate various biological activities, such as immune modulation, antioxidant, antidiabetic, and hypolipidemic. However, litter is known about the interaction of these polysaccharides with the gut microbiota. This study aimed to evaluate the effects of marine algae Enteromorpha (Ulva) prolifera polysaccharide (EP) supplementation on growth performance, immune response, and caecal microbiota of broiler chickens. A total of 200 1-day-old Ross-308 broiler chickens were randomly divided into two treatment groups with ten replications of ten chickens in each replication. The dietary treatments consisted of the control group (fed basal diet), and EP group (received diet supplemented with 400 mg EP/kg diet). Results showed that chickens fed EP exhibited significantly higher (P &lt; 0.05) body weight and average daily gain than the chicken-fed basal diet. In addition, significantly longer villus height, shorter crypt depth, and higher villus height to crypt depth ratio were observed in the jejunal and ileal tissues of chickens fed EP. EP supplementation upregulated the mRNA expression of NF-κB, TLR4, MyD88, IL-2, IFN-α, and IL-1β in the ileal and jejunal tissues (P &lt; 0.05). Besides, we observed significantly higher (P &lt; 0.05) short-chain volatile fatty acids (SCFAs) levels in the caecal contents of the EP group than in the control group. Furthermore, 16S-rRNA analysis revealed that EP supplementation altered gut microbiota and caused an abundance shift at the phylum and genus level in broiler chicken. Interestingly, we observed an association between microbiota and SCFAs production. Overall, this study demonstrated that supplementation of diet with EP promotes growth performance, improves intestinal immune response and integrity, and modulates the caecal microbiota of broiler chickens. This study highlighted the application of marine algae polysaccharides as an antibiotic alternative for chickens. Furthermore, it provides insight to develop marine algae polysaccharide-based functional food and therapeutic agent.