An in Vitro Study on The Antimicrobial Activity and Antioxidant Activities of The Extract of A Seaweed, Enteromorpha Intestinalis Against Certain Pathogens

Seaweeds are potential bio resources of marine ecosystem and they are the producers of marine ecological energy chain and also possess many bioactive compounds with them. The seaweed Enteromorpha intestinalis is the plant material chosen for the study and was collected from the Pulicat estuary. The collected seaweeds were processed to synthesise nanoparticles out of them and the synthesised silver nanoparticle’s in vitro antimicrobial and antioxidant activity was evaluated. The antibacterial activity was determined by the action against Salmonella typhi, Pseudomonas aeruginosa, Staphylococcus aureus, Vibrio parahaemolyticus and Micrococcus luteus. Similarly the in vitro antifungal effect was also explored against Candida albicans, Trichoderma viridae, Aspergillus niger, Rizhopus sp and Penicillium notatum. Among them, Staphylococcus aureus and Aspergillus niger were found to be highly susceptible to the synthesised nanoparticles. When the antioxidant efficacy of synthesized nanoparticle was tested using different methods such as DPPH and ABTS it was observed that they possessed appreciable antioxidant property whose efficiency was correlated with their respective positive standards. These investigations illustrated the potential effects of the seaweed E. intestinalis for using them as an active antimicrobial and antioxidant agent.

Long-term dynamics of aquatic vegetation and the state of ecosystems of soda lakes in southeastern Transbaikalia

The cyclical nature of long-term changes in the annual amounts of atmospheric precipitation in Transbaikalia controls most of the processes in ecosystems. The paper briefly describes the long-term vegetation dynamics of soda lakes in the southeast of Transbaikal territory. These dynamics are driven by changes in abiotic parameters of the lakes, mainly water salinity and pH values. When the values of these indicators increase, the perennial succession series of vegetation of higher plants is as following: Helophytes + Neustophytes + Hydatophytes → Helophytes + Hydatophytes → Helophytes. The succession series of macrophytic algae is as following: Stigeoclonium sp. or Spirogyra sp. → Cladophora fracta + Charophyta → Enteromorpha intestinalis.

A New Biofertilizer Formulation with Enriched Nutrients Content from Wasted Algal Biomass Extracts Incorporated in Biogenic Powders

Raw algae waste naturally thrown on shores could pose serious threats for landfilling and its reuse for composting or further processing as added-value by-products require knowledge-based decisions and management for the sustainable development of local ecosystems. Raw marine waste containing salt (halite) and heavy metals that eventually accumulate in algae hamper their safe applicability in soil fertilization or in other exploitations. Here, the suitability of algal biomass for use as an environmentally safe fertilizer was investigated, thereby supporting sustainable coastal management. The simple extraction of the dry algal biomass of three abundant Mediterranean species, Enteromorpha intestinalis, Corallina elongata, and Gelidium pulchellum, in water containing sodium carbonate resulted in a greenish extract containing a reduced heavy metals content, and nutrients such as K+, PO43−, SO42−, NO3−, Ca2+, and Mg2+. UV-Vis and Raman techniques, including surface-enhanced Raman scattering (SERS), were employed for the fast evidencing of polyphenols, carotenoids, and chlorophylls in the extracts content, while E. intestinalis extract additionally exhibited polysaccharide signals. Heavy metals analysis showed that the major metals in the extracts were Fe, Ni, Zn, and Cu; however, their levels were an order of magnitude lower than in the dry biomass. The extracts also showed a mild antibacterial effect. The combination option of aqueous extracts with powdered crustacean shells to obtain a novel, eco-friendly, solid biofertilizer complex was further shown, which could be pelleted for convenient use. The immersion of solid biofertilizer pellets in water is accompanied by re-solubilization of the compounds originating from algae extracts, presenting the opportunity for dry storage and easier handling and land applicability. In summary, aqueous extracts of marine algae waste present an environmentally safe and attractive way to recycle excessive algal biomass and to formulate a new, eco-friendly biofertilizer complex.

Bioprocess development for biosorption of cobalt ions and Congo red from aquatic mixture using Enteromorpha intestinalis biomass as sustainable biosorbent

Because of the increased amount of cobalt and Congo red dye effluents attributable to the industrial operations, the capacity of Enteromorpha intestinalis biomass as a sustainable source to achieve significant biosorption percent for both pollutants from dual solution was assessed. A fifty batch FCCCD experiments for biosorption of cobalt ions and Congo red dye were performed. The complete removal of Congo red dye was obtained at 36th run using an initial pH value of 10, 1.0 g/L of Enteromorpha intestinalis biomass, 100 and 200 mg/L of Congo red and cobalt for a 20-min incubation time. Meanwhile, a cobalt removal percent of 85.22 was obtained at 35th run using a neutral pH of 7.0, 3.0 g/L of algal biomass, 150 and 120 mg/L of Congo red, and cobalt for a 60-min incubation time. For further illustration and to interpret how the biosorption mechanism was performed, FTIR analysis was conducted to inspect the role of each active group in the biosorption process, it can be inferred that –OH, C–H, C=O, O–SO3- and C–O–C groups were mainly responsible for Co2+ adsorption of from aqueous dual solution. Also, scan electron microscope revealed the appearance of new shiny particles biosorbed on E. intestinalis surface after the biosorption process. EDS analysis proved the presence of Co2+ on the algal surface after the biosorption process.

Содержание липидов в макрофитах разных районов прибрежной акватории Севастополя (Чёрное море)

Проведено обобщение материалов по содержанию липидов в массовых видах водорослей-макрофитов, обитающих в прибрежных водах Севастополя, в районе бухт Артиллерийской, Карантинной, Казачьей, Балаклавской, Нефтегавани, парка Победы, Приморского бульвара. Содержание липидов в зелёных водорослях Ulva rigida в среднем составляет 2–5 % сухого веса, Enteromorpha intestinalis ― 2–3 %, в красных водорослях Callithamnion corymbosum ― 3–4 %, Ceramium rubrum ― 2–3 %, в бурой водоросли Cystoseira barbata ― 2 % сухого веса. Чёткой зависимости количества липидов от сезона года не установлено, но отмечена тенденция повышенного содержания липидов в водорослях из районов с большей степенью загрязнения. В эксперименте по влиянию соляра при трёхсуточной экспозиции статистически достоверной разницы в содержании липидов от их первоначальной концентрации в ульве не отмечено. В присутствии мидийных выделений, выступающих в роли своеобразного удобрения, наблюдается увеличение содержания липидов.

Culture of Three Seaweed Species in Cox’s Bazar Coast, Bangladesh

The experimental culture of 3 seaweed species, i.e. Hypnea musciformis, Enteromorpha intestinalis and Padina tetrastromatica in three locations of Cox’s Bazar coast, Bangladesh using 4×4 m horizontal coir rope net method were conducted during 2016 to 2018. Results showed that the biomass yield was highest from H. musciformis (30.23±0.40 kg fw m−1) and significantly differ from E. intestinalis (24.50±0.08 kg fw m−1) and P. tetrastromatica (10.18±0.45 kg fw m−1). The Daily Growth Rate (DGR) of H. musciformis (8.88% day−1) was also higher than the DGR of E. intestinalis (6.55% day−1) and P. tetrastromatica (6.74% day−1). Saint Martin’s Island showed higher biomass yield of seaweeds than Bakkhali and Inani due to favourable water quality. In context to physico-chemical parameters of seaweed farming, Cox's Bazar coast is suitable for seaweed cultivation, although more suitable culture areas and longer culture period yet to be identified. The findings of the present study suggest that the cultivation of H. musciformis is viable and coastal people can take up such activities as seasonal income generating activity in coastal water. Bangladesh J. Zool. 49(1): 47-56, 2021

Preliminary Investigation of the Antioxidant, Anti-Diabetic, and Anti-Inflammatory Activity of Enteromorpha intestinalis Extracts

Marine algae are a promising source of potent bioactive agents against oxidative stress, diabetes, and inflammation. However, the possible therapeutic effects of many algal metabolites have not been exploited yet. In this regard, we explored the therapeutic potential of Enteromorpha intestinalis extracts obtained from methanol, ethanol, and hexane, in contrasting oxidative stress. The total phenolic (TPC) and flavonoids (TFC) content were quantified in all extracts, with ethanol yielding the best values (about 60 and 625 mg of gallic acid and rutin equivalents per gram of extract, respectively). Their antioxidant potential was also assessed through DPPH•, hydroxyl radical, hydrogen peroxide, and superoxide anion scavenging assays, showing a concentration-dependent activity which was greater in the extracts from protic and more polar solvents. The α-amylase and α-glucosidase activities were estimated for checking the antidiabetic capacity, with IC50 values of about 3.8 µg/mL for the methanolic extract, almost as low as those obtained with acarbose (about 2.8 and 3.3 µg/mL, respectively). The same extract also showed remarkable anti-inflammatory effect, as determined by hemolysis, protein denaturation, proteinase and lipoxygenase activity assays, with respectable IC50 values (about 11, 4, 6, and 5 µg/mL, respectively), also in comparison to commercially used drugs, such as acetylsalicylic acid.

Antioxidant, antibacterial and cytotoxic activity of Caulerpa racemosa (Forsskål) J. Agardh and Ulva (Enteromorpha) intestinalis L.

Seaweeds are fresh sources of phytochemical compounds with immense medicinal potential, which have attracted the attention of agriculture, aquaculture and the pharmaceutical industry. The aim of this study was to test the antioxidant, antibacterial and cytotoxic activity and screening the phytochemical properties of methanol crude extract from two green seaweeds Caulerpa racemosa (Forsskål) J.Agardh and Ulva (Enteromorpha) intestinalis L. The antioxidant and cytotoxic activity of these seaweeds were assessed by 2,2diphenyl, 1-picryl hydrazyl (DPPH) free radical scavenging technique and brine shrimp lethality bioassay method, respectively. The antibacterial activities against Vibrio fluvialis was determined using the standard disc diffusion method. The U. intestinalis showed higher total phenolic content with the value of 149.87 ± 18.17 mg of GAE/g than 73.95 ± 16.09 mg of GAE/g of C. racemosa. However, the recorded inhibition concentration (IC50) to corresponding standards ascorbic acid of C. racemosa and U. intestinalis were 119.62 and 34.274 μg/mL, respectively. The values were statistically significant (p <0.05) compared to the reference antioxidative agent ascorbic acid. In antibacterial assay, C. racemosa extract showed higher inhibition zone (22.65 ± 0.58 mm) than U. intestinalis (17± 0.28 mm). Moreover, U. intestinalis exhibited a lower LC50 value than C. racemosa in cytotoxic activity. Phytochemical analysis revealed that these two seaweeds have alkaloids, flavonoids, glycosides, phenols, saponins, steroids and tannins. Bangladesh J. Sci. Ind. Res.55(4), 237-244, 2020