Native Algal Species Research Articles

Biosorption of some elements by algae from a cutinite-rich coal and its effect on organic geochemical composition: A case study from Abu Thora, Sinai, Egypt

A Carboniferous-age unique cutinite-rich coal seam at Wadi Abu Thora in Sinai, Egypt, was subjected to biosorption extraction of uranium (U) and thorium (Th) by five native algal species. These algal species were used in the biosorption process with the coal acting as a cultivation substrate. The concentration of U and Th was measured before and after the biosorption process. The five algal species used included Sarconema filofirms, Ulva Lactuca, Sargassum detofiulum, Caulerpa prolifera, and Cystoseira osmundacea, in addition to the yeast Saccharomyces cerevisiae. Two species, namely Caulerpa prolifera and Cystoseira osmundacea, were able to grow and adhere well to the coal particles as indicated by the microscopic examination in fluorescence mode. The above two species showed a capability to biosorb U and Th completely followed by Sarconema filofirms (56.7%, 18.7 ppm), Ulva Lactuca (49.4%, 16.3 ppm), and Sargassum detofiulum (40.3%, 13.3 ppm). These three species were successful in the uptake of U, alongside Saccharomyces cerevisiae, which showed a greater capability (58.2% or 19.2 ppm U). Biosorption by Caulerpa prolifera and Cystoseira osmundacea algae is an effective procedure to extract U and Th from this coal. Coal macerals played an important role in U precipitation, reflecting the structure of the compound that contains the U. Extraction of U and Th by biosorption resulted in changes in the cutinite-rich coal sample. Geochemical evaluation of the treated samples reflects a change in their chemical structure with the partial or complete removal of carboxyl/carbonyl-only groups in addition to the n-alkane chains. Pyrolysis data indicated shorter n-alkane-alkene compounds and smaller ratios. Data show that algae play a role in the biotransformation of absorbed organic matter composition by type and quantity. Finally, these compositional changes may produce more mature organic matter from the parent sample.

Algal biofuels: Technological perspective on cultivation, fuel extraction and engineering genetic pathway for enhancing productivity

Vast utilization and subsequent depletion of fossil fuels have forced to development of new approaches for finding a suitable alternative to fossil fuels. Algae remain a promising tool for producing third generation biofuels such as biodiesel, biohydrogen, bioethanol, etc and make them suitable material for bioenergy production. However, commercial application of biofuels from algal species is restricted due to cost for production, limitations in cultivation and harvesting and processing. This review focuses on various types of biofuels such as biodiesel, biohydrogen, bioethanol and biogas from different algal species utilizing cultivation systems such as raceway ponds and photobioreactors. The challenges in producing biofuels from native algal species are defined for finding alternative approach. This paper also focuses on the genetic engineering approaches available for modifying the pathway in algal species for increasing biomass and biofuel production. Metabolic activity can be enhanced using biochemical engineering. Hence the combined application of these approaches can help to take over the demerits of producing biofuels using algae. The cost required for biofuel production depends on the type of algal cultivating system and its challenge remains in harvesting and separation processes after cultivation.

Rapid Spread of the Invasive Brown Alga Rugulopteryx okamurae in a National Park in Provence (France, Mediterranean Sea)

The temperate Northwest Pacific brown alga Rugulopteryx okamurae (Dictyotales, Phaeophyceae) was first discovered in 2002 in the Mediterranean Sea in the Thau coastal lagoon (Occitania, France) and then again in 2015 along the southern side of the Strait of Gibraltar, where it was assigned with invasive status. We report here on the first occurrence of the species in the Northwest Mediterranean Sea in Calanques National Park (Marseille, France) in 2018. By 2020, a large population had developed, extending over 9.5 km of coastline, including highly protected no-take zones. The seafood trade, with R. okamurae used as packing material for sea urchin Paracentrotus lividus shipments from Thau Lagoon, could be the vector of its introduction into the Marseille area. As observed in the Strait of Gibraltar, R. okamurae is spreading rapidly along the Marseille coasts, suggesting an invasive pathway. The subtidal reefs are densely carpeted with R. okamurae, which overgrows most native algal species. Fragments of the alga are continuously detached by wave actions and currents, sedimenting on the seabed and potentially clogging fishing nets, and thus, impacting artisanal fishing or washing up on the beaches, where they rot and raise concern among local populations.

Algal Biorefinery for the Extraction of Bioactive Compounds

Background: Algae, tiny photosynthetic microorganisms are under investigation for commercial biofuels and biochemical production. Applications of bioactive compounds of algal origin are now increasing for food, feed, fodder, fibre, cosmetics, nutraceutical and pharmaceuticals. Recent years have witnessed a major thrust moving towards a sustainable, biobased economy using a biorefinery concept. The biorefinery concept is based on obtaining a broad spectrum of products such as biodiesel, bioethanol, biogas, jet fuels, and many value-added biobased products from renewable bioresources analogous to the petroleum refinery. Methodology: The aim of this review is to provide an insight into the utilization of algal biomass for the production of bioactive compounds, algal cultivation systems, cell disruption techniques, challenges to algal bioactive compound extraction, and offer a way forward. According to this objective, we did a comprehensive search in all available electronic information resources like in Web of Science, Scopus, and Science Direct. Result: The review summarizes representative bioactive compounds from algal biomass, indicating that these biological resources are an inexhaustible source of new molecules that often display unique structures and sometimes have very interesting pharmacological properties, such as antifungal, antibacterial, enzyme-inhibitory, and other activities. A better cultivation and cell disruption strategy have been suggested for a sustainable algal biorefinery system. Conclusion: The paper reviewed different bioactive compounds like astaxanthin, DHA, EPA, vitamins and β-1,3 Glucan, etc. present in microalgae and their applications in pharmaceuticals and nutraceuticals development for human consumption along with major steps of algal bioprocessing, such as algal cultivation and cell disruption. Also, the production and role of several high-value compounds extracted from algal biomass in the treatment of various diseases along with the way forward to make algal-based biorefinery for bioactive compounds economically sustainable and viable have been discussed. However, research on various aspects of algal based bioactive compound extraction is in a nascent phase and requires bioprospecting of high yielding native algal species, development and deployment of mass cultivation strategies, process optimization for harvest and cell disruption techniques followed by efficient biomolecule extraction procedures to make algal biorefinery sustainable and commercially viable in nature.

INVESTIGATION ON ALGAL BIOMASS PROGRESSION IN POLLUTED POND WATER - THE WAY FORWARD

Municipal wastewater treatment is a global issue and an expensive process. Treatment of the wastewater using algal growth is a cost-effective approach, because of easy propagation of algae in wastewaters through utilization of most of the nutrients and in turn reduces the pollution load. As a preliminary research work, laboratory scale studies were done using native algal species collected from particular sources. They were grown in different pond waters to observe the biomass development in comparison to their growth in their original source pond water. Results showed that algal biomass was highest in the pond water, from which the algal sample was obtained followed by other pond water samples, artificial media and control. Biomass showed positive correlations with improvement in water quality parameters and a stationary phase was observed in the later stages of growth. The study also supports the use of native algal species for treatment of wastewaters. Excessive algal growth in water bodies is a serious environmental issue, however in a long-term perspective this biomass can also be harnessed for various other end uses along with wastewater treatment.

A cost-effective and environmentally sustainable process for phycoremediation of oil field formation water for its safe disposal and reuse

High volumes of formation water comprising of complex mixture of hydrocarbons is generated during crude oil exploration. Owing to ecotoxicological concerns, the discharge of the formation water without remediation of hydrocarbonaceous pollutants is not permitted. Keeping this into mind, we carried out phycoremediation of hydrocarbons in formation water so that it can be safely discharged or re-used. For this, a native algal species was isolated from formation water followed by its morphological and 18S ribosomal RNA based identification confirming the algal isolate to be Chlorella vulgaris BS1 (NCBI GenBank Accession No. MH732950). The algal isolate exhibited high biomass productivity of 1.76 gm L−1 d−1 (specific growth rate: 0.21 d−1, initial inoculum: 1500 mg L−1) along with remediation of 98.63% petroleum hydrocarbons present in formation water within 14 days of incubation indicating an efficient hydrocarbon remediation process. Concomitantly, the hydrocarbon remediation process resulted in reduction of 75% Chemical Oxygen Demand (COD) load and complete removal of sulfate from formation water making it suitable for safe disposal or reuse as oil well injection water respectively. The present process overcomes the bottlenecks of external growth nutrient addition or dilution associated with conventional biological treatment resulting in a practically applicable and cost-effective technology for remediation of oil field formation water.

The invasive green alga Avrainvillea sp. transforms native epifauna and algal communities on a tropical hard substrate reef

SUMMARYSome introduced species compete directly with native species for resources and their spread can alter communities, while others do not proliferate and remain benign. This study compares community structure and diversity in adjacent areas dominated by the introduced alga Avrainvillea sp. or native algal species on a hard substrate reef. The biomass and species composition of 15 paired plots (30 in total, plot type based on dominance of Avrainvillea sp. or native species) were quantified. Plots dominated by Avrainvillea sp. had a significantly different assemblage of species characterized by lower algal diversity, mostly Dictyota spp. and Laurencia sp., and a higher abundance and diversity of invertebrates, such as small arthropods, polychaetes, and brittlestars. These results suggest that as Avrainvillea sp. becomes more abundant on hard substrate reefs, it will engineer a different community composed of algal epiphytes and an invertebrate assemblage more typically associated with algae in soft sediments.

Biodiversity influences invasion success of a facultative epiphytic seaweed in a marine forest

The biotic resistance hypothesis predicts that more diverse communities should have greater resistance to invasions than species-poor communities. However for facultative and obligate epiphytic invaders a high native species richness, abundance and community complexity might provide more resources for the invader to thrive to. We conducted surveys across space and time to test for the influence of native algal species abundance and richness on the abundance of the invasive facultative epiphytic filamentous alga Lophocladia lallemandii in a Mediterranean Cystoseira balearica seaweed forest. By removing different functional groups of algae, we also tested whether these relationships were dependent on the complexity and abundance of the native algal community. When invasion was first detected, Lophocladia abundance was positively related to species richness, but the correlation became negative after two years of invasion. Similarly, a negative relationship was also observed across sites. The removal experiment revealed that more complex native communities were more heavily invaded, where also a positive relationship was found between native algal richness and Lophocladia, independently of the native algal abundance. Our observational and experimental data show that, at early stages of invasion, species-rich seaweed forests are not more resistant to invasion than species-poor communities. Higher richness of native algal species may increase resource availability (i.e. substrate) for invader establishment, thus facilitating invasion. After the initial invasion stage, native species richness decreases with time since invasion, suggesting negative impacts of invasive species on native biodiversity.

Coral reef grazer-benthos dynamics complicated by invasive algae in a small marine reserve

Blooms of alien invasive marine algae have become common, greatly altering the health and stability of nearshore marine ecosystems. Concurrently, herbivorous fishes have been severely overfished in many locations worldwide, contributing to increases in macroalgal cover. We used a multi-pronged, interdisciplinary approach to test if higher biomass of herbivorous fishes inside a no-take marine reserve makes this area more resistant to invasive algal overgrowth. Over a two year time period, we (1) compared fish biomass and algal cover between two fished and one unfished patch reef in Hawai’i, (2) used acoustic telemetry to determine fidelity of herbivorous fishes to the unfished reef, and (3) used metabarcoding and next-generation sequencing to determine diet composition of herbivorous fishes. Herbivore fish biomass was significantly higher in the marine reserve compared to adjacent fished reefs, whereas invasive algal cover differed by species. Herbivorous fish movements were largely confined to the unfished patch reef where they were captured. Diet analysis indicated that the consumption of invasive algae varied among fish species, with a high prevalence of comparatively rare native algal species. Together these findings demonstrate that the contribution of herbivores to coral reef resilience, via resistance to invasive algae invasion, is complex and species-specific.

Characterization of algal and microbial community growth in a wastewater treating batch photo-bioreactor inoculated with lake water

Microalgae grown in photo-bioreactors can be a valuable source of biomass, especially when combined with wastewater treatment. While most published research has studied pure cultures, the consortia of algae and bacteria from wastewater have more complex community dynamics which affect both the biomass production and pollutant removal. In this paper we investigate the dynamics of algal and bacterial growth in wastewater treating batch photo-bioreactors. The photo-bioreactors were inoculated with water from a nearby lake. Lake water was obtained in August, November and December in order to add native algal species and study the effects of the season. The photo-bioreactors inoculated with lake water obtained in August and November produced more biomass and grew faster than those that only contained the algae from wastewater. The results indicated a rapid decline in bacterial abundance before algae began to multiply in reactors supplemented with lake water in November and December. The reactors were also successful in removing nitrogen and phosphorous from wastewater.

Implications of nutrient removal and biomass production by native and augmented algal populations at a municipal wastewater treatment plant.

Algal monocultures (Chlorella sorokiniana and Botryococcus braunii) and algal communities native to clarifiers of a wastewater treatment plant were batch cultivated in (1) clarified effluent following a biochemical oxygen demand (BOD) removal reactor post-BOD removal clarified effluent (PBCE), (2) clarified effluent following a nitrification reactor post-nitrification clarified effluent (PNCE), and (3) a reference media (RM). After 12 days, all algal species achieved nitrogen removal between 68 and 82% in PBCE and 37 and 99% in PNCE, and phosphorus removal between 91 and 100% in PBCE and 60 and 100% in PNCE. The pH of the wastewater samples increased above 9.8 after cultivation of each species, which likely aided ammonia volatilization and phosphorus adsorption. Both monocultures grew readily with wastewater as a feedstock, but B. braunii experienced significant crowding from endemic fauna. In most cases, native algal species' nutrient removal efficiency was competitive with augmented algal monocultures, and in some cases achieved a higher biomass yield, demonstrating the potential to utilize native species for nutrient polishing and algal biomass production.

Investigating Two Native Algal Species to Determine Antibiotic Susceptibility Against some Pathogens

The aim of present study was to investigate antimicrobial activity of two algal species <em>Pithophora oedogonium</em> and <em>Botrydiopsis arhiza</em> against four bacterial species: <em>Salmonella</em> 1 (egg), Salmonella 4 (meat 2), <em>Staphylococcus</em> sp., 4978 and <em>Staphylococcus</em> sp., 5034 and four fungal species viz: <em>Aspergillus niger</em> 419, <em>Aspergillus flavus</em> 1110, <em>Penicillium viridicatum</em> 1101 and <em>Fusarium solini</em> 1127. The algal cell mass was extracted in 100% ethanol and further concentrations of 2, 4, 6 and 8 mg/mL were made. Antagonistic effects were tested by using disc-diffusion method for bacterial species and agar well technique for fungal species. <em>B. arhiza</em> did not exhibit antimicrobial activity against all the test organisms. Whereas the ethanol extract of <em>P. oedogonium</em> inhibited the growth of two bacterial and two fungal species viz: <em>Salmonella 1</em> (egg), <em>Staphylococcus</em> sp., 4978, <em>F. solini</em> and <em>P. viridicatum</em>. The maximum activity was observed against <em>F. solini</em> (22.3 mm) at 2 mg/mL conc. applied. It was noted that the growth of <em>Salmonella 1</em> (egg) was inhibited maximally at 4 mg/m Lshowing zone of inhibition of 7, 4.67 and 4 mm at 6 and 8 mg/mL conc., respectively. The inhibitory zones of 7 and 3 mm were recorded for <em>Staphylococcus</em> sp., 4978 at 4 and 8 mg/mL conc. used. Among fungal species <em>P. viridicatum</em> showed maximum Zone of Inhibition (ZOI) of 7.6 mm at 8 mg/mL conc. The ethanolic extract of <em>P. oedogonium</em> can be efficiently used in antibiotics production as it proved effective against <em>Salmonella 1</em> (egg), <em>Staphylococcus</em> sp., 4978, <em>P. viridicatum</em> and <em>F. solini</em>.

Detrital diversity influences estuarine ecosystem performance

Global losses of seagrasses and mangroves, eutrophication-driven increases in ephemeral algae, and macrophyte invasions have impacted estuarine detrital resources. To understand the implications of these changes on benthic ecosystem processes, we tested the hypotheses that detrital source richness, mix identity, and biomass influence benthic primary production, metabolism, and nutrient fluxes. On an estuarine muddy sandflat, we manipulated the availability of eight detrital sources, including mangrove, seagrass, and invasive and native algal species that have undergone substantial changes in distribution. Mixes of these detrital sources were randomly assigned to one of 12 treatments and dried detrital material was added to seventy-two 0.25m(2) plots (n=6 plots). The treatments included combinations of either two or four detrital sources and high (60g) or low (40g) levels of enrichments. After 2months, the dark, light, and net uptake of NH4 (+) , dissolved inorganic nitrogen, and the dark efflux of dissolved organic nitrogen were each significantly influenced by the identity of detrital mixes, rather than detrital source richness or biomass. However, gross and net primary productivity, average oxygen flux, and net NOX and dissolved inorganic phosphorous fluxes were significantly greater in treatments with low than with high detrital source richness. These results demonstrate that changes in detrital source richness and mix identity may be important drivers of estuarine ecosystem performance. Continued impacts to estuarine macrophytes may, therefore, further alter detritus-fueled productivity and processes in estuaries. Specific tests that address predicted future changes to detrital resources are required to determine the consequences of this significant environmental problem.

Seasonal variations in fatty acid composition of Caulerpa taxifolia (M. Vahl.) C. Ag. in the northern Adriatic Sea (Malinska, Croatia)

Fatty acid composition was monitored in Caulerpa taxifolia collected from January to December 1998 in the northern Adriatic Sea. Saturated (45.2–73.7%), monounsaturated (10.3–25.9%) and polyunsaturated (16–34.3%) fatty acid proportions varied considerably during the period investigated. The Caulerpa growth cycle proceeded through a) minor changes during the latent and growth recruitment phase in spring, b) a gradual increase in unsaturated fatty acids during maximum growth in the summer/early autumn period and c) an abrupt increase, particularly of polyunsaturated fatty acids, during biomass maintenance and survival as lowering temperatures approached the lethal level. These variations were similar to those found in native algal species of temperate regions. Stimulation of growth and spreading can be partly explained by successful adaptation of C. taxifolia to the seasonality of environmental parameters (primarily temperature).

Expansion of the macroalga Caulerpa racemosa and changes in softbottom macrofaunal assemblages in Moni Bay, Cyprus

The recent expansion of the Red Sea macroalga Caulerpa racemosa and its impact on the diversity and abundance of macrobenthos were examined and compared in the summers of 1992 and 1997, in Moni Bay, Cyprus. The phytobenthic community of the bay in 1992 was dominated by the seagrass Posidonia oceanica while, in 1997, the Lessepsian migrant C. racemosa became the most dominant, forming extensive mats. Changes in the vegetation system in Moni Bay have caused significant compositional changes in macrofaunal assemblages. A total of 178 individuals of 62 species are recorded. The composition of the macrofauna in 1992 was dominated by gastropods (44 %), crustaceans (22%), bivalves (17 %), polychaetes (11 %) and echinoderms (6 %). In 1997, the gastropods and crustaceans had decreased to 13 % and 16 % respectively, while, polychaetes had increased to 38 % becoming the most dominant taxon. Bivalves and echinoderms also increased to 22 % and 11 %, respectively, in 1997. The proliferative growth of C. racemosa imposed successional changes on the macrofaunal assemblages in Moni Bay, Cyprus, between 1992 and 1997. It remains to be tested whether the expansion of C. racemosa is related to the increase of water temperature associated with global warming or nutrient inputs or with the differences in the life history characteristics of this migrant vs. native algal species.