Vegetative Propagation of the Commercial Red Seaweed Chondracanthus chamissoi in Peru by Secondary Attachment Disc during Indoor Cultivation.

Chondracanthus chamissoi is an edible red seaweed with a high hydrocolloid content and food industry demand. This situation has led to a decline in their populations, especially in Peru. An alternative culture method based on the formation of secondary attachment discs (SADs) has shown several advantages over traditional spore strategies. However, there are still scarce reports of the SAD method in Peru. This work aimed to evaluate the best conditions for C. chamissoi maintenance prior to SAD development and the effect of locality on SAD formation using scallop shells as a substratum. Experiments were conducted with material collected from five localities in Pisco (Ica, Peru). Our results showed that the best conditions for C. chamissoi maintenance were: (1) fertilized seawater with Bayfolan® (0.2 mL L-1); and (2) medium exchange every two days or weekly. These conditions reduced the biomass loss to 9.36-11.14%. Most localities showed a similar capacity to produce SADs (7-17 SADs shell-1). However, vegetative algae, especially Mendieta, tended to present a higher number of SADs. Vegetative fronds also showed lower levels of necrosis and deterioration compared to cystocarpic and tetrasporophytic samples. This study shows the technical feasibility of culturing C. chamissoi through SADs for developing repopulation and/or intensive cultivation projects in Peru.

Sulfated Galactofucans: An Outstanding Class of Fucoidans with Promising Bioactivities.

Fucoidans encompass versatile and heterogeneous sulfated biopolysaccharides of marine origin, specifically brown algae and marine invertebrates. Their chemistry and bioactivities have been extensively investigated in the last few decades. The reported studies revealed diverse chemical skeletons in which l-fucose is the main sugar monomer. However, other sugars, i.e., galactose, mannose, etc., have been identified to be interspersed, forming several heteropolymers, including galactofucans/fucogalactans (G-fucoidans). Particularly, sulfated galactofucans are associated with rich chemistry contributing to more promising bioactivities than fucans and other marine polysaccharides. The previous reports in the last 20 years showed that G-fucoidans derived from Undaria pinnatifida were the most studied; 21 bioactivities were investigated, especially antitumor and antiviral activities, and unique biomedical applications compared to other marine polysaccharides were demonstrated. Hence, the current article specifically reviews the biogenic sources, chemistry, and outstanding bioactivities of G-fucoidans providing the opportunity to discover novel drug candidates.

Protoplast isolation from Dictyopteris pacifica and Scytosiphon lomentaria, using a simple commercial enzyme preparation.

BACKGROUND: Protoplasts (i.e., naked plant cells) can be used for in vitro manipulations and genetic improvement in cultivars with economic value. During the last decade, protoplast research in economic brown algae has been scarce, and it is usually hampered by the use of non-commercial enzymes or crude extracts for isolating protoplasts. Dictyopteris pacifica is part of a brown algal genus well known by its wide chemical diversity and biological properties. Scytosiphon lomentaria is an edible brown seaweed with antioxidant, antitumor, and antiviral properties. So far, there are no protoplast isolation protocols using commercial enzymes for these two economic brown algae. In this study, we obtained protoplasts from cultured samples of D. pacifica and S. lomentaria using commercially available enzymes. Additionally, we investigated the effects of Driselase inclusion and Ca-chelation pre-treatment on protoplast yields in order to optimize the conditions for protoplast preparations. RESULTS: Protoplasts were isolated from Dictyopteris pacifica and Scytosiphon lomentaria using the commercially available Cellulase Onozuka RS (1%) and Alginate lyase (4 U mL-1), and short incubation time (4 h). Driselase did not show significant effects on protoplast production in both species. Ca-chelation pre-treatment only increased the number of protoplasts in D. pacifica. Under optimal conditions, the protoplast yields from D. pacifica and S. lomentaria were 4.83 ± 2.08 and 74.64 ± 32.49 × 106 protoplasts g-1 fresh weight, respectively. The values obtained for S. lomentaria were 2-3 orders of magnitude higher than previously reported. CONCLUSIONS: Our results show that high protoplast yields can be obtained from D. pacifica and S. lomentaria using a simple mixture of commercial enzymes (Cellulase RS and Alginate lyase) and short incubation time (4 h). This work also represents the first report of protoplast isolation in D. pacifica. The method proposed here can help to expand protoplast technology in more brown algal species.