Algae Fiber Research Articles

Suitability of Residues from Seaweed and Fish Processing for Composting and as Fertilizer

There is a need to find novel sources of fertilizers to meet the increasing food demands of a growing human population and alternatives to mined and synthetic fertilizers for the certified organic sector. Composting is a common method for processing and stabilizing organic residues for use in horticulture. To that end, a small-scale composting experiment with six combinations of dried and ground rockweed (Ascophyllum nodosum), algae fiber from chemically processed rockweed, ground bones and fishmeal from cod (Gadus morhua), and ground blue mussels (Mytilus edulis) was conducted in Dewar flasks to assess whether these residues are suitable for composting and have potential for use as fertilizers. Expanded clay aggregates were used as a bulking material. Physicochemical analyses were performed on the residues and their mixtures before and after composting, and the temperature in the flasks was monitored for 92 days. Suitability was determined by evaluating the temperature dynamics, changes in physiochemical parameters, and nutrient profiles. All treatments generated heat, with reductions in C/N ratio, weight, and volume, demonstrating suitability for composting. The treatments with algae fiber had a higher mean temperature (34.5 vs. 29.0 °C) and more degree days above the thermophilic range (mean = 176- vs. 19-degree days), the greatest reduction in volume (mean = 35% vs. 27%), and the lowest C/N ratios at the end of active composting (18 vs. 24) compared to the treatments with dried and ground seaweed. In terms of fertilizer value, none of the finished composts were balanced for use as fertilizers alone and, in some cases, contained too much Na, but contained sufficient concentrations of K, S, Mg, and Ca and could be a valuable source of these nutrients and organic matter in combination with other N- and P-rich sources.

An overview on red algae bioactive compounds and their pharmaceutical applications.

Objectives To review red algae bioactive compounds and their pharmaceutical applications. Content Seaweed sources are becoming attractive to be used in health and therapeutics. Among these red algae is the largest group containing bioactive compounds utilized in cosmetic, pharmaceutical, food industry, manure and various supplements in food formula. Various significant bioactive compounds such as polysaccharides (aginate, agar, and carrageenan), lipids and polyphenols, steroids, glycosides, flavanoids, tannins, saponins, alkaloids, triterpenoids, antheraquinones and cardiac glycosides have been reported in red algae. The red algae have rich nutritional components Different polysaccharides of red algae possess the antiviral potential namely agarans, carrageenan, alginate, fucan, laminaran and naviculan. Sulfated polysaccharides and carraginans of red algae are rich source of soluble fibers which can account for antitumor activities depending upon chemistry of various secondary metabolites and metabolism of cell line. Flavons-3-ols containing catechins from many red algae block the telomerase activity in colon cancer cells. Contraceptive agents were tested from red algae as a source for post-coital. Lectin of red algae showed pro-healing properties and anti-ulcerogenic activities. Carragenates from red algae also conferred a positive influence on diabetes. Red algae depicted a reducing effect on plasma lipids and obesity. Porphyran from red alga can act as anti-hyperlipidemic agent also reduces the apolipoprotein B100 via suppression of lipid synthesis in human liver. Summary The polyphenolic extracts of Laurencia undulate, Melanothamnus afaqhusainii and Solieria robusta extract show anti-inflammatory effects against multiple genera of devastating fungi. Antioxidants such as phlorotannins, ascorbic acids, tocopherols, carotenoids from red algae showed toxicity on some cancer cells without side effects. Red algae Laurencia nipponica was found insecticidal against mosquito larvae. Red algae fibers are very important in laxative and purgative activities. Gracilaria tenuistipitat resisted in agricultural lands polluted with cadmium and copper. Outlook In the recent decades biotechnological applications of red algae has been increased. Polysaccharides derived from red algae are important tool for formulation of drugs delivery system via nanotechnology.

Enterosorption Properties of Arctic Brown Algae Fiber

Enterosorption properties of algae fiber were studied. Determination of the thermodynamic characteristics of heavy metal sorption showed that the process is endothermic with the prevalence of chemisorption interactions. Algae fiber exhibits high sorption capacity for heavy metals and pathogenic microorganisms.

Determination of diffusion parameters and biosorption of cadmium in aqueous solution using algae biomass

ABSTRACTThe objective behind this study is to investigate the phenomenon and kinetics of Cd(II) ion biosorption by the algae fibers, as well as the development of mathematical model that would describe the phenomenon of ions transport through porous algae. The results obtained have shown an inter-particle rate constant of diffusion Kint = 0.188 (mg·g−1·min−1/2), R2 = 0.999, and adsorption amount at equilibrium QSeq = 1.87 mg·g−1. These results indicated that the diffusion of ions existed in the porous algae. The proposed mathematical model is used to optimize the biosorption of heavy metal ions by connecting the model parameters with the fiber performances.

Algae fiber polypropylene composites: Modeling of the degradation by solid state kinetics

ABSTRACTKnowledge of the mechanisms of degradation in natural fiber composites (NFCs) has great importance for the life cycle assessment of the automotive components based on NFCs. The purpose of this study was to evaluate the solid state kinetic models available to describe the degradation process of algae fiber/grafted polypropylene (AFPPg) composites processed by extrusion compression molding (ECM). Samples of the 0.14 volume fraction (υf) AFPPg composite, algae fiber, and grafted PP were evaluated before and after 576 hours of accelerated UV light weatherization. The weight loss of the specimens was determined by thermogravimetric analysis (TGA) at six isothermal temperatures, and weight loss data were transformed into the conversion fraction α. Curves of the factor α and time were linearized using MATLAB software to find the parameters of the degradation. The best statistical fit to model the degradation was given by the Avrami–Erofe'ev model. The kinetic parameters of PP grafted after UV exposure were frequency factor (A) of 6.26 min−1 and activation energy E0 of 24 kJ/mol. The effect of degradation was characterized by Fourier transformed infrared spectroscopy (FTIR). The characteristic bands of the main products of degradation in the composite were identified as pentane and propane. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44622.

Production of new cellulose nanomaterial from red algae marine biomass Gelidium elegans

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.

Compression molding of algae fiber and epoxy composites: Modeling of elastic modulus

The demand for natural fiber composites in the automotive industry in both Europe and the United States has been forecasted to increase in the coming years. The natural fiber composites based on highly commercialized fibers such as flax, hemp, and sisal has grown to become an important sector of polymeric composites. However, little attention has been addressed to expanding natural fiber composites to include new sources of emerging natural reinforcements, such as reclaimed algae fibers, that have a multiple environmental benefits. Not only are extracted algae fibers biodegradable, the reclamation process has the added benefit of restoring health of waterways choked with algae. This study focuses on the processability of algae fiber–epoxy composites. Short fibers, chemically extracted from raw reclaimed algae, were prepared for natural fiber composite products in two ways. First, randomly oriented mats were produced using the wet-laid process to create layered, compression-molded laminates. Second, loose fibers were dispersed directly into the thermoset matrix to produce a bulk molding compound that was further compression molded into composite lamina. The effect of processing variables such as compaction pressure, temperature, and time were addressed. Moreover, the effect of fiber volume fraction ( υf) and fiber form were considered. Enhanced mechanical properties were found when 56% υf algae fiber was used for the compression-molded laminates composite. This variant exhibited an improvement on the flexural and tensile modulus of 70% and 86% when compared to the neat epoxy. However, the volume of porosity on the same variant was 11% due to lack of compression in some of the fibers. The effect of porosity on the theoretical stiffness was estimated by using the Cox–Krenchel model. Furthermore, an empirical exponential model was formulated to characterize the multi-scale effect of compaction pressure on the overall fiber volume fraction, υf.

Utilization of algae blooms as a source of natural fibers for biocomposite materials: Study of morphology and mechanical performance of Lyngbya fibers

Algae blooms represent a worldwide contamination problem, 55% of the water bodies in the U.S. are in poor condition mainly because of algae. A second source of algae waste is the co-product of the algae biofuel process. There is potentially an abundant source of algae fiber; however, little is known about the utilization of algae as reinforcement for natural fiber composites (NFC). The purpose of this work is to study the morphology and mechanical properties of the blue-green algae Lyngbya as a natural fiber reinforcement for biocomposite materials according to the Standards ASTM-D792-00 and ASTM C1557-03. Lyngbya were sourced and by conducting a sequence of chemical treatments on the algae the fiber that was extracted. The average properties of Lyngbya fiber are: density 1.06g/cm3, width 60μm, tensile strength of 215MPa, and tensile modulus of 24GPa. Lyngbya fiber properties are comparable to jute and sisal fibers.

Physical and bio-composite properties of nanocrystalline cellulose from wood, cotton linters, cattail, and red algae

Nanocrystalline celluloses (NCCs) were isolated from different cellulose sources such as wood (softwood and hardwood), non-wood plant (cotton linters and cattail), and marine pulp (red algae) by acid hydrolysis. The NCCs were compared with respect to their dimensions, shapes, degrees of polymerization, crystallinities, thermal stabilities, and effects on the properties of bio-composites. Self-assembly phenomena of the NCCs were observed by electron microscopy. The NCCs from red algae fibers had the longest length (~432 nm) and the highest aspect ratio among the five cellulose sources. The NCCs from cotton linters, cattail fibers, and red algae fibers showed greater thermal degradation resistance than those from wood fibers. The NCCs with much lower molecular weights than their starting materials showed much higher crystalline indices than their starting ones. All-cellulose bio-composites, where the prepared NCCs were used as filaments and the dissolved cellulose as matrix, displayed increased Young’s moduli in proportion to the added amount of the NCCs.

Bondable and Biodegradable Cellulosic Opacifiers

Fibers extracted from red algae produced a comparable increase in paper opacity to that produced by experimented inorganic fillers, calcium carbonate. Red algae fibers consist predominantly of cellulose and contain less than 1% inorganic ash. They are comparable to wood fibers in terms of their bonding, combustion, recycling, and biodegradation. While the bonding strength properties of paper decreased with an increase of inorganic fillers in the amount added to the paper, the red algae fibers maintained their bonding properties. These special characteristics seem to stem from the relatively large specific surface areas of the red algae fibers, which are relatively short (0.4–0.8 mm) and narrow (2–4 μm). Moreover, the addition of red algae fibers to the paper increased the paper stretch and folding endurance in proportion to their added amount. These special properties of red algae fibers may find application in low-basis weight printing paper grades that require high opacity and strength.

Effect on modified nanoclay on dynamic mechanical and thermomechanical properties of natural fiber/polypropylene biocomposites

This study was conducted to investigate the effect of nanoclay addition on thermal and dynamic mechanical properties of polypropylene (PP) biocomposites reinforced with bleached red algae fiber (BRAF), kenaf fiber (KF), and cotton pulp fiber (CPF). The nano-biocomposites were fabricated with 40 wt.% loading of all natural fibers and addition of nanoclay at 5 or 10 wt.% loading by the melting compounding and compression molding techniques. The nanoclay effects on the thermal and dynamic mechanical properties of the biocomposites were analyzed as a function of properties of natural fibers such as chemical composition, fiber length, and surface morphology. Although the thermal decomposition temperature of nano-biocomposites decreased with the addition of nanoclay, the dimensional stability of biocomposites greatly improved with increasing nanoclay loading. Also, the dynamic mechanical properties of nano-biocomposites for the PP reinforced with BRAF, KF, and CPF were enhanced with the addition of 5 wt% nanoclay compared to those of biocomposites without nanoclay. The highest enhancement in dimensional stability was obtained for the nano-biocomposites reinforced with BRAF natural fiber. These increases can be attributed to a uniform distribution of nanoclay and to a good interfacial adhesion between the reinforcement and PP matrix. The well dispersed nanoclay particles can have good interactions with both natural fibers and polymer matrix, with the incorporation of the reinforcing natural fibers restricting the mobility of the polymer molecules resulting in the raised storage modulus values.

Algal biomass anaerobic biodegradability

We conducted a series of biodegradation studies using microalgae (Arthrospira maxima and Nannochloropsis sp.) and macroalgae (Gelidium corneum and Cladophora glomerata) to elucidate algal biodegradability in wastewater sludge under anaerobic conditions. Algal biodegradability was evaluated according to ASTM D5210-92. The results indicate that A. maxima biodegraded to a greater extent (70 %) than Nannochloropsis sp. (40 %). The low level of mineralization for Nannochloropsis sp. is due to the presence of high level of lipids (37 %). For macroalgal samples, red algae fiber pulped from G. corneum biodegraded comparably to cellulose controls. However, C. glomerata biodegradation is about 46 %. A sample compositional analysis revealed that it contained about 24.5 % ash, which is directly accountable for an observed low degree of biodegradation. Algal anaerobic biodegradability is important to facilitate sludge digester design and performance evaluation. It is particularly useful when waste residual materials from algal biofuel processing are used for energy production.

Use of New Fibers for the Development of Security Paper

Use of security papers for monetary papers, gift certificates, and lottery tickets increases every year. As the use of security papers increase, there are more possibility of counterfeits. In this study, we used unique fibers from the sea to increase the difficulties against counterfeiting. The red algae fibers give opacity as much as calcium carbonates, and have unique shape in length (<TEX>$500{\sim}900\;{\mu}m$</TEX>) and width (<TEX>$1{\sim}4\;{\mu}m$</TEX>) to be discerned from other natural fibers such as wood and cotton fibers. We mixed red algae fibers to wood fibers in a series of fixed ratios to make single and multiply papers for making security papers. Paper with dyed red algae fibers were also used. Paper made without fillers gave enough opacity for printing when red algae fibers were used more than 20% of the fiber furnish. Those properties may allow red algae fibers to be a potential candidate for fiber raw materials of security paper.

Biosorption behaviors of natural polymer microfibers synthesized by using cellulase-based enzyme reactions

This study introduces a facile enzymatic reaction approach to the synthesis of red algae (Gelidium aman- sii) microfibers. Through use of a suitable cellulase enzyme, entangled red algae fiber networks could be divided into single microfibers, which enlarges their surface area and generates more hydroxyl groups on their surfaces. The microfibers obtained after this enzyme reaction showed an excellent ability to take up heavy metals; in fact, the absorption efficiency was reversely proportional to fiber length. Under optimal conditions, these microfibers reduced their length and size deviation to ~92% and ~95%, respectively, at which the heavy metal absorbance effi- ciency increased to ~230% compared with that of red algae biomass. It was also found that solution pH affected the heavy metal adsorption behaviors due to a change in charge density; maximal heavy metal adsorption of heavy met- als was observed at pH 9. These results highlight that our algae microfibers produced using the biofriendly enzyme reaction could be utilized as an effective remover of harmful species from water media.

Optical Properties of Red Algae Fibers

Red algae fibers extracted from red algae (seaweed) showed very high opacity when used in the manufacture of white paper. For a basis weight of 60 g/m 2 , over 90% opacity was observed in paper made from red algae fibers without the aid of mineral fillers, whereas papers made from wood fibers had 70-80% opacity. Mercury porosimetry and light reflectance measurements at various wavelengths were used to investigate the origin of such high opacities in red algae fibers. The results revealed that red algae fibers had an extraordinarily high specific surface area on account of their very narrow widths (2-4 µm) and short lengths (500-800 µm). This unique property of red algae fibers can be best utilized for manufacturing highly opaque, premiumgrade, lightweight printing papers without lowering the paper strength properties.

Dynamic mechanical and thermal properties of red algae fiber reinforced poly(lactic acid) biocomposites

This study compared the dynamic mechanical and thermal properties of biocomposites reinforced with algae fiber; polypropylene (PP) and poly(lactic acid) (PLA) biocomposites. The biocomposites are manufactured with a bleached red algae fiber (BRAF) loading ranging from 30 to 60 wt%. The thermal properties of BRAF, PLA and PP were determined by DSC and TGA. The dynamic mechanical and thermomechanical properties of the PLA matrix and biocomposites were analyzed by DMA and TMA. The dynamic mechanical and thermomechanical properties of both BRAF/PLA and BRAF/PP biocomposites show improvement with increasing BRAF loading. The fibers were well bonded with the PLA matrix, indicating strong adhesion, as observed by SEM observations of the fractured surface. In addition, greater improvement in the storage modulus was achieved with the BRAF/PLA biocomposites than with the BRAF/PP biocomposites. Therefore, BRAF/PLA biocomposites can be used as an alternative completely biodegradable biocomposite to BRAF/PP biocomposites.

Biocomposites based on sea algae fibers and biodegradable thermoplastic matrices

Composites were prepared by mixing thermoplastic biodegradable polymers with sea algae fibers. Tensile mechanical properties were analyzed as a function of fiber concentration. The effect of processing, such as compression molding and calendering, on the mechanical properties of the materials was investigated. Composites showed higher elastic modulus and lower strength than the matrix components. Fiber damaging, characterized by a reduction of both length and diameter, was observed in the composites. Films, prepared by calendering operations, showed anisotropic properties due to fiber alignment. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 583–592, 1999