Evaluation of Mechanical Properties of Polysaccharide Films Prepared from Furcellaria Lumbricalis and Gigartina Skottsbergii Seaweeds by PF-QNM Technique

Films from Furcellaria lumbricalis (FL) and Gigartina skottsbergii (GS) seaweed extracts were prepared and their properties were investigated. According to NMR analysis of GS ultrasonic water (GSUW) extraction (1-3)-α-glycan 6-sulfate was isolated. The analogical treatment with carbonate-peroxide solution (GSUCP) resulted in a mixture of the same glycan and carrageenan hybrids µ-D6S and ν-D2S,6S observed for the first time in this study. The extraction of GS in boiling water under reflux (GSW) in comparison to FL (FLW), indicates that GSW consisted of the most complex mixture of α-, β-, κ-, ι-, θ-, ζ-carrageenans, (1-3)-α-glycan partially sulfated at C6, and µ-D6S and ν-D2S,6S hybrids. The analogical FLW extract contained α-, θ-, λ-, µ-, ν- and ζ-carrageenans and (1-3)-α-glycan partially sulphated at C6. SEC-MALS results indicate that molecular weight of chromatographic main peak (Mp) is decreasing: GSUCP (994 kg/mol) > GSUW (565 kg/mol) > FLW (498 kg/mol) > ι-carrageenan (264 kg/mol) > κ-carrageenan (174 kg/mol) > furcellaran (144 kg/mol) > GSW (78 kg/mol). Macromolecules conformation is varying from flexible random coil for κ-carrageenan to nearly compact spheres for ι-carrageenan. Furcellaran conformation is intermediate between κ-carrageenan and ι-carrageenan, specifically a little more compact than κ-carrageenan. XRD analysis confirmed no cellulose content in all prepared films. AFM and PF-QNM analysis showed relations between values of Rg and Mp and the values of surface roughness, reduced moduli, stiffness and adhesion.

Analysis of the influence of storms on massive marine litter wash-outs to the shore of the Sambian Peninsula

<p>The problem of contamination of the shore of the Sambian Peninsula with marine anthropogenic litter is pressing and requires detailed study since it has a detrimental effect on the touristic and recreational activity of the region. Observations show that the most volumetric marine litter wash-outs to the beach take place after certain storms and are associated with abundant spots ofbiota (primarily branched Furcellaria lumbricalis). Such spots contain litter of anthropogenic origin, such as glass, paper, etc., along with macro and micro plastics. In this paper, meteorological and hydrophysical data were collected and analyzed in order to determine the most significant factors causing the wash-outs of anthropogenic marine litter to the shore of Sambian Peninsula. Both in-situ observations and reanalysis datasets were used for the analysis. It was revealed that the wash-out to the shore occurs during the storm subsiding phase, and the determining factors are significant wave height, wind speed and current velocity during the preceding storm.</p><p>Investigations are supported by the Russian Science Foundation, grant No 19-17-00041 and IKBFU competitiveness improvement program for 2016-2020 (project 5-100).</p>

BALTIC AMBER MIGRATIONS AS A MODEL OF MICROPLASTICS BEHAVIOR IN THE SEA COASTAL ZONE

The problem of microplastic pollution is of increasing concern. Behaviour of microplastic particles (0.5 mm < L < 5mm in the largest dimension) in marine environment is difficult to predict, and no field observations are available up to now. Baltic amber (succinite), with its density of about 1.05-1.09 g/cm3, fits the range of densities of slightly negatively buoyant plastics: polyamide, polystyrene, acrylic, etc. Baltic citizens have observed amber migrations for centuries, and the collected information may shed some light onto general features of microplastic particles behaviour. Events of “amber washing-out” at the sea shore of the Sambian peninsula (Kaliningrad oblast, Russia) typically take place in autumn-winter time. Experience of divers indicates that amber is washed out from the depths as deep as 15 m. Massive presence in amber-containing debris of the red algae Furcellaria lumbricalis, dominating in the sea at depths of 6-15 m, proves this fact. From oceanographic viewpoint, important for the “amber washing-out” are: strong and long-lasting storm, phase of wind decrease or direction change, developed long surface waves, shore exposure to wind. Analysis of characteristic wave lengths after long storms, dimensions of their surf zone, and changes in underwater bottom profile is carried out. Conclusion is that slightly negatively buoyant microplastic particles should migrate for a long time between beaches and underwater slopes until they are broken into small enough pieces that can be transported by currents to deeper area and deposited out of reach of stormy waves.

BALTIC AMBER MIGRATIONS AS A MODEL OF MICROPLASTICS BEHAVIOR IN THE SEA COASTAL ZONE

The problem of microplastic pollution is of increasing concern. Behaviour of microplastic particles (0.5 mm < L < 5mm in the largest dimension) in marine environment is difficult to predict, and no field observations are available up to now. Baltic amber (succinite), with its density of about 1.05-1.09 g/cm3, fits the range of densities of slightly negatively buoyant plastics: polyamide, polystyrene, acrylic, etc. Baltic citizens have observed amber migrations for centuries, and the collected information may shed some light onto general features of microplastic particles behaviour. Events of “amber washing-out” at the sea shore of the Sambian peninsula (Kaliningrad oblast, Russia) typically take place in autumn-winter time. Experience of divers indicates that amber is washed out from the depths as deep as 15 m. Massive presence in amber-containing debris of the red algae Furcellaria lumbricalis, dominating in the sea at depths of 6-15 m, proves this fact. From oceanographic viewpoint, important for the “amber washing-out” are: strong and long-lasting storm, phase of wind decrease or direction change, developed long surface waves, shore exposure to wind. Analysis of characteristic wave lengths after long storms, dimensions of their surf zone, and changes in underwater bottom profile is carried out. Conclusion is that slightly negatively buoyant microplastic particles should migrate for a long time between beaches and underwater slopes until they are broken into small enough pieces that can be transported by currents to deeper area and deposited out of reach of stormy waves.

Biotechnological applications of the red alga Furcellaria lumbricalis and its cultivation potential in the Baltic Sea

There is a growing need for diversification of seaweed aquaculture practices in Europe. In the Baltic Sea, very few seaweed species are utilised commercially, and only the kelp