A high-performance porous biochar adsorbent prepared by facile thermal pyrolysis of seaweed (Gelidiella acerosa) is reported. The textural characteristics of the prepared seaweed biochar (SWBC) and the performance in the adsorption of methylene blue (MB) dye were evaluated. The batch experiment for the adsorption of MB was conducted under different parameters, such as temperature, pH, and initial concentration of MB in the range of 25-400 mg/L. The developed SWBC exhibited a relatively high surface area, average pore size, and pore volume of 926.39 m2/g, 2.45 nm, and 0.57 cm3/g, respectively. The high surface area and pristine mineral constituents of the biochar promoted a high adsorption capacity of 512.67 mg/g of MB at 30 °C. The adsorption isotherm and kinetics data best fitted the Langmuir and pseudo-second-order equations. The results indicate that SWBC is efficient for MB adsorption and could be a potential adsorbent for wastewater treatment.
Nanocellulose was successfully isolated from Gelidium elegans red algae marine biomass. The red algae fiber was treated in three stages namely alkalization, bleaching treatment and acid hydrolysis treatment. Morphological analysis was performed by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). TEM results revealed that the isolated nanocellulose had the average diameter and length of 21.8±11.1nm and of 547.3±23.7nm, respectively. Fourier transform infrared (FTIR) spectroscopy proved that the non-cellulosic polysaccharides components were progressively removed during the chemically treatment, and the final derived materials composed of cellulose parent molecular structure. X-ray diffraction (XRD) study showed that the crystallinity of yielded product had been improved after each successive treatments subjected to the treated fiber. The prepared nano-dimensional cellulose demonstrated a network-like structure with higher crystallinity (73%) than that of untreated fiber (33%), and possessed of good thermal stability which is suitable for nanocomposite material.
The world at large is facing a new threat with the emergence of the Coronavirus Disease 2019 (COVID-19) pandemic. Though imperceptible by the naked eye, the medical, sociological and economical implications caused by this newly discovered virus have been and will continue to be a great impediment to our lives. This health threat has already caused over two million deaths worldwide in the span of a year and its mortality rate is projected to continue rising. In this review, the potential of algae in combating the spread of COVID-19 is investigated since algal compounds have been tested against viruses and algal anti-inflammatory compounds have the potential to treat the severe symptoms of COVID-19. The possible utilization of algae in producing value-added products such as serological test kits, vaccines, and supplements that would either mitigate or hinder the continued health risks caused by the virus is prominent. Many of the characteristics in algae can provide insights on the development of microalgae to fight against SARS-CoV-2 or other viruses and contribute in manufacturing various green and high-value products.
The aim of this work was to evaluate the efficacy of red macroalgae Eucheuma cottonii (EC) as feedstock for third-generation bioethanol production. Dowex (TM) Dr-G8 was explored as a potential solid catalyst to hydrolyzed carbohydrates from EC or macroalgae extract (ME) and pretreatment of macroalgae cellulosic residue (MCR), to fermentable sugars prior to fermentation process. The highest total sugars were produced at 98.7 g/L when 16% of the ME was treated under the optimum conditions of solid acid hydrolysis (8% (w/v) Dowex (TM) Dr-G8, 120°C, 1h) and 2% pretreated MCR (P-MCR) treated by enzymatic hydrolysis (pH 4.8, 50°C, 30 h). A two-stream process resulted in 11.6g/L of bioethanol from the fermentation of ME hydrolysates and 11.7 g/L from prehydrolysis and simultaneous saccharification and fermentation of P-MCR. The fixed price of bioethanol obtained from the EC is competitive with that obtained from other feedstocks.