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There has been a growing demand for efficient disposal of kelp waste. Microbial degradation is a win–win bio-solution for seaweeds waste disposal and acquisition of nutritious byproducts. In this study, the cooperation of an alginate lyase producing bacteria (Paenibacillus sp. QBH) and cellulase producing bacteria (Enterococcus sp. N1) was applied for its high degrading efficiency of kelp waste. Serial single factor experiments revealed that temperature, shaking speed and degradation time were the key factors impacting the alginate lyase and filter paper assay activities upon hydrolyzing kelp waste by N1 + QBH combination. Via response surface method optimization, predicted models for the alginate lyase and filter paper assay activities asserted the highest values could be attained at the temperature 34 °C, shaking speed 180 rpm and degradation time 4.5 days. This prediction was verified by a triplicate experiment giving an average alginate lyase activity of 61.2 U mL−1 and filter paper assay activity of 6.12 U mL−1. Biodegradation of kelp waste by N1 + QBH combination under optimizing conditions remarkably promoted the release of sugars, total phenolic compounds, various minerals and amino acids, generating a nutritious hydrolysate with a total organic matters yield of 56.3 g L−1, total phenolic compounds yield of 18.3 mg g−1 dry weight and total amino acids concentration of 247.3 mg L−1. This study highlights that N1 + QBH combination could be a feasible solution for bioconversion of kelp waste to sustainable production of biostimulant. [ABSTRACT FROM AUTHOR]

Protoplast systems are essential for genome-editing and gene silencing technologies. In brown algae, protoplast isolation has been hampered by protocols that use non-commercial enzymes or crude extracts. This study is the first to report the production of protoplasts from cell-filament suspension cultures of the brown alga, Hecatonema terminale (Kützing) Kylin, using different mixtures of commercial enzymes and chelation pre-treatment. In this study, mixture A (cellulase RS and alginate lyase) with chelation pre-treatment produced the highest number of protoplasts (3.52 ± 0.23 × 105 protoplasts g−1 FW). Chelation pre-treatment showed high effects on all kinds of enzyme mixtures. The effects of these different mixtures were examined by two-way ANOVA. We also investigate the optimal protoplast density and regeneration medium for protoplast regeneration. Of 16 combinations for regeneration media, RM1 with lowest initial protoplast density (2.4 × 103 protoplasts mL−1) showed the highest value (74%) of final plating efficiency (FPE) after 13 days of culture. The well-defined heterotrichous thalli with phaeophycean hairs were clearly distinguished after 22 days of culture. [ABSTRACT FROM AUTHOR]

This study assesses the effect of different milling pre-treatments on enzymatic glucose release from the brown seaweed Laminaria digitata having high glucan (laminarin) content . Wet refiner milling, using rotating disc distances of 0.1-2 mm, generated populations of differently sized pieces of lamina having decreasing average surface area (100-0.1 mm) with increased milling severity. Higher milling severity (lower rotating disc distance) also induced higher spontaneous carbohydrate solubilization from the material. Due to the seaweed material consisting of flat blades, the milling did not increase the overall surface area of the seaweed material, and size diminution of the laminas by milling did not improve the enzymatic glucose release. Milling was thus not required for enzymatic saccharification because all available glucose was released even from unmilled material. Treatment with a mixture of alginate lyase and a cellulase preparation (Cellic®CTec2) on large-sized milled material released all available glucose within 8 h. Application of the cellulase preparation alone released only half of the available glucose. The alginate lyase catalysis apparently induced selective removal of alginate to improve the cellulase catalyzed degradation of laminarin and cellulose in the material. [ABSTRACT FROM AUTHOR]

There is a growing demand for the efficient treatment of seaweed biomass and the production of seaweed-degrading enzymes. Fifteen algicolous fungi were isolated from the Red Sea macroalgae in Egypt and were studied for their capability of utilizing Sargassum and Palisada biomass and subsequent production of different thallus-degrading enzymes. Most of the fungi efficiently saccharified the macroalgal extracts that amounted to more than 70 % of the sugars in the unfermented macroalgal extract. Algicolous fungi fermented Sargassum through extracellular fucoidanases and alginases that were negatively correlated as revealed by principal component analysis (PCA), suggesting an antagonistic degradation of Sargassum polysaccharides. Extracellular agarases resulted in efficient fermentation of Palisada biomass . Fungi expressed also amylase and protease activities that were low or nonexistent and biomass-dependent. Amylase showed positive correlation with agarase as indicated by PCA, which suggests that the two enzymes synergistically degrade Palisada biomass. The enzymatic cocktails were also able to release reducing sugars from the powdered macroalgal thalli, indicating the importance of enzymes in the saprophytic growth of fungi. Generally, enzymatic activities and specific activities of fucoidanase, alginase, and agarase in algicolous fungi were higher than reported previously for non-algicolous fungi. Enzymatic activities of the marine brown algal pathogen Lindra thalassiae indicated that infection by this pathogen might occur through alginases. The results shed light into production of less expensive enzymatic mixtures from an understudied group of microorganisms targeting seaweed-degradation. These enzymes have many biotechnological and industrial applications as thallus maceration and protoplast isolation despite bioactivity of obtained oligosaccharides. [ABSTRACT FROM AUTHOR]

The extracellular enzyme alginate lyase produced from marine fungus Aspergillus oryzae isolated from brown alga Dictyota dichotoma was purified, partially characterized, and evaluated for its sodium alginate depolymerization abilities. The enzyme characterization studies have revealed that alginate lyase consisted of two polypeptides with about 45 and 50 kDa each on 10% sodium dodecyl sulfate polyacrylamide gel electrophoresis and showed 140-fold higher activity than crude enzyme under optimized pH (6.5) and temperature (35°C) conditions. Zn, Mn, Cu, Mg, Co and NaCl were found to enhance the enzyme activity while (Ca, Cd, Fe, Hg, Sr, Ni), glutathione, and metal chelators (ethylenediaminetetraacetic acid and ethylene glycol tetraacetic acid) suppressed the activity. Fourier transform infrared and thin-layer chromatography analysis of depolymerized sodium alginate indicated the enzyme specificity for cleaving at the β-1,4 glycosidic bond between polyM and polyG blocks of sodium alginate and therefore resulted in estimation of relatively higher polyM content than polyG. Comparison of chemical shifts in C nuclear magnetic resonance spectra of both polyM and polyG from that of sodium alginate also showed further evidence for enzymatic depolymerization of sodium alginate. [ABSTRACT FROM AUTHOR]

A new extraction protocol has been developed to obtain high quality DNAfrom Laminaria japonica, which involves enzymatic dissociation ofsporophyte tissues and subsequent elimination of the remainingpolysaccharides with cetyltrimethyl ammonium bromide. Unicells isolatedfrom frozen kelp tissues with alginate lyase prepared from the abalone Haliotis diversicolor were used to extract total DNA; the yield wasapproximately 13 to 22.5 μg DNA g-1 (wet sporophyteweight). The average size of genomic DNA was around 23 kb estimated byagarose gel electrophoresis, and the purity of total DNA determinedspectrophotometrically as the ratio of OD260/OD280 wasabout 1.7. The extracted kelp DNA (20–40 ng) could be usedsuccessfully as a template for polymerase chain reaction (PCR) under theoptimized conditions (100 μM dNTP, 0.2 μM primer, 1.0unit Taq DNA polymerase). The random amplified polymorphicDNA (RAPD) patterns were highly reproducible. These results suggest thatthe contamination by soluble polysaccharides which interferes with RAPDreproducibility was largely controlled. This RAPD-suited method for DNAextraction from kelp sporophytes using enzyme treatment providedsufficient material, and was inexpensive and convenient to carry out. [ABSTRACT FROM AUTHOR]