There is a growing demand for the efficient treatment
of seaweed biomass and the production of seaweeddegrading
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 seaweeddegradation.
These enzymes have many biotechnological
and industrial applications as thallus maceration and protoplast
isolation despite bioactivity of obtained oligosaccharides

The study of fungal species diversity from
marine algae is in its infancy; as now no studies have
been carried out on the distribution and diversity of
fungi on the surfaces of marine macroalgae where all
fungal–algal interactions tend to begin. The aim of this
study was to isolate and describe the culturable part of
mycobiota associated with the surface of benthic
marine macroalgae (epiphytic or epibiotic fungi). This
is an important step in understanding their abundance,
diversity and factors influencing their variability and
composition. The fungal community was dominated
by Ascomycetes (89%) with Eurotiales as the most
abundant fungal order followed by Capnodiales,
Pleosporales, and Hypocreales, while Zygomycetes
was less frequent. The nature of occurrence of fungal
genera on different macroalgal hosts suggests that a
mix of generalists’ framework applies to fungal
epiphytes of seaweeds, but the abundance of fungal
taxa varied among ecological functional groups of
algae, as well as macroalgal taxonomic groups, which
imply host filtering. The fungal assemblages were also
characterized by temporal variation with variation in
temperature, pH, and salinity as the most important
abiotic factors. The structure of fungal assemblages
showed high beta diversity and low similarity between
hosts.

NULL

β Diversity is an ecological concept used to
describe the turnover of species across a wide range of
spatial and temporal scales, but such knowledge is lacking
for macroalgal assemblages of the Red Sea. β Diversity patterns
for Red Sea macroalgae were evaluated from different
sites (Hurghada, Safaga, and Al-Quseir) and seasons
across different environmental disturbances. β Diversity
was studied by partitioning the total number of species (γ
diversity) into additive components. Geographical heterogeneity
was more important than seasonal heterogeneity
in structuring macroalgae both at species and functional
group levels. Species replacement as a component of β
diversity produced dissimilarity in species composition
and taxonomic structure. Replacement of species between
sites was responsible for the presence of new functional
groups of macroalgae. High β diversity and taxonomic
similarity values were characteristic of the macroalgae of
the Red Sea. The occurrence of small macroalgal thalli that
have short life cycles induced high species replacement
and subsequently high β diversity, with spatial heterogeneity
and environmental gradient as drivers of β diversity.
Anthropogenic disturbance at the Safaga site was suggested
to induce variation of macroalgal assemblages and
functional groups. Excluding rare species from the data
set did not change the high values of b diversity.

The study aimed to assess the effect-combined use different of date palm composts amended with
ligno-cellulolytic fungi and mineral-N on growth and N, P and K-uptake of maize plants in sandy
calcareous soil. Each type of compost was applied either in organic form in dose equivalent to
100% of N fertilization (285 kg ha-1) or in organic form in combination with mineral-N (50% for
each). The experiment was constructed in a complete randomized block design (CRBD). Results
showed that plant height and dry weight of shoot and root of maize significantly increased as a
result of the combined use of compost with mineral-N (1:1, w:w). All types of composts combined
with half-dose of mineral-N was effective, however, compost that contained with Aspergillus niger +
A. subsessilis + Trichoderma lanuginosus + Bacillus sp. was the best. This type of fertilization
increased N-uptake shoot and root of maize more than mineral N-fertilizer by 39.73%-49%. Inaddition, the P-uptake by shoot and root of maize increased by 58.82%-156%. The addition of
compost treatments to the soil increased the total N, P and K after harvesting. Regression analysis
showed positive and significant linear correlation between the application rate of compost and the
availability of P and K in soil.

There is a growing demand to find an effective extraction process of sulfated polysaccharides from brown
algae to conserve its structure and biological activity. Fucoidan was recovered from Sargassum sp. using a
hot buffer extraction process. BoxeBenhken experimental design was evaluated to study different
conditions of temperature, pH and buffer: alga ratio on fucoidan yield and its sulfate content. By solving
the regression equations and analyzing 3-D plots, the optimum conditions were at extraction temperature
60
C, pH 4.0, and ratio of buffer: alga 10.0 mL/g. Under these conditions, the experimental fucoidan
yield, and sulfate content were 19 and 47.6% (w/w), respectively, which were in good agreement with the
predicted values. The use of hot buffer extraction was efficient to obtain a high fucoidan yield with
maintaining high sulfate contents. Fucoidan preparations showed variations in antioxidant properties
using various antioxidant assays. Increasing reducing antioxidant activity and hydroxyl radical scavenging
of fucoidan extracts was attributed to increasing total sugars, fucose, and uronic acids. The data
obtained suggested that the sulfate groups might act as reductones rather than radical scavengers to
contribute to the antioxidant activity of fucoidan. Additionally, proteinaceous and phenolic compounds
co-extracted with crude fucoidan contributed to its antioxidant potential. Crude fucoidan demonstrated
good emulsion stabilizing capacities, especially with cedar wood oil and xylene. These results suggest the
use of the crude fucoidan as a good alternative to many synthetic polymers, as well as other natural
polysaccharides, in several applications in the food, pharmaceutical, cosmetic, textile, paper and petroleum
industries.

The screening of potential antioxidant activities of hydrophobic (ethyl acetate) and hydrophilic (polysaccharide) extracts from both mycelia and fermentation media of eleven algicolous fungi was performed using three antioxidant assays. Algicolous fungi were able to ferment low-cost nutrients composed of potato infusion, glucose, and natural seawater and produce hydrophobic and hydrophilic metabolites with antioxidant properties. Significant differences were observed in antioxidant activities of extracts from the various species evaluated using total antioxidant activity (TAA), hydroxyl radical scavenging activity (HRSA), and ferric reducing antioxidant power (FRAP), as well as their total sugar contents (TSC) of hydrophilic extracts and total phenolic contents (TPC) of hydrophobic extracts. TSC of endopolysaccharides was higher than exopolysaccharides and showed a significant correlation with both TAA and FRAP. Most of mycelial extracts were richer in phenolics than fermentation media, and TPC of hydrophobic extracts was significantly correlated with their FRAP. Mycelial extracts for most of algicolous fungi showed higher antioxidant activities than fermentation media. Both hydrophobic and hydrophilic extracts of algicolous fungi showed good antioxidant properties, especially as hydrogen-donating antioxidants, which could be considered for future applications in medicine, food production, or cosmetic industry.