The comparison of the properties of nanocellulose isolated from colonial and solitary marine tunicates

Abstract

This is the first comparative of tunicate cellulose nanocrystalline (t-CNC) from colonial and solitary tunicates. The t-CNC from the colonial tunicate Eudistoma sp. (CL1) was compared with solitary tunicates Polycarpa reniformis (CL2) and Phallusia nigra (CL3). Tunicate samples were extracted by methanol. Residues from the methanol extraction were then subjected to further cellulose purification using pre-hydrolysis, kraft-cooking, bleaching, and sulfuric acid hydrolysis to yield t-CNC. The solitary tunicates yielded higher microfibril contents after the bleaching step but obtained similar t-CNC content to the colonial one after acid hydrolysis. The isolated t-CNC were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermalgravimetric analysis, and transmission electron microscopy. Both colonial and solitary tunicates yielded cellulose type I. The pure cellulose type I was successfully isolated from solitary tunicates whereas high inorganic impurities were observed in colonial tunicates. The isolate t-CNC showed high aspect ratios. The solitary and colonial tunicates provided t-CNC with crystallinity indexes over 97% and 35%, respectively. The crystalline size of t-CNCs ranged from 55-124 Å. The thermal stability of all isolated t-CNC was slightly decreased due to the sulfate functional groups gained after acid hydrolysis. We concluded that solitary tunicates were better than colonial tunicates as a source of t-CNC preparation.

Nanocellulose-Based Hybrid Scaffolds for Skin and Bone Tissue Engineering: A 10-Year Overview

“…is rare. 106,107 The tunicate capsule from which cellulose is derived has the natural ability to heal damaged tissue and has a composition similar to human body fluid which makes it an excellent polymer to be used for biomedical applications. 107,108 Green macroalgae Ulva is commercially cultivated, as it is a widely used edible seaweed.…”

“…The aquaculture of tunicates for production of cellulose can be advantageous in the sense that carbon sequestration can be returned to the ocean floor. − The tunicate cellulose extracted from its outer capsule, tunic, is superior to plant cellulose with a highly reactive surface area, which makes it an excellent source as a composite material. Tunicates of class Ascidiacea also called sea squirts are the only variety that can produce cellulose, and they are the main focus of researchers for cellulose production . The nanofibers from tunicates have widths ranging from 10 to 30 nm and lengths ranging from 100 nm-2 μm, producing type I cellulose with high strength and purity.…”

“…, and cellulose production from colony tunicates such as Eudistoma sp. is rare. , The tunicate capsule from which cellulose is derived has the natural ability to heal damaged tissue and has a composition similar to human body fluid which makes it an excellent polymer to be used for biomedical applications. , Green macroalgae Ulva is commercially cultivated, as it is a widely used edible seaweed. Ulva lactuca does not consist of lignin, and lignin free nanocellulose extraction can be done with this species .…”

Synthesis, characterization and application of nanocrystalline cellulose: A review

“…One tunicate species that has been extensively studied for its cellulose content is the sea squirt (Halocynthia roretzi). This animal is capable of producing large amounts of cellulose in a short period of time and has been shown to produce cellulose with a high degree of crystallinity and tensile strength [17].…”

Emerging Food Packaging Applications of Cellulose Nanocomposites: A Review

“…Cellulose is the most abundant biopolymer on Earth. It can be synthesized by trees [ 7 ], plants [ 8 ], sea animals (tunicates) [ 9 ], algae [ 10 ], and certain cellulose-secreting bacteria [ 11 ], and the properties of the cellulose are also found to be source-dependent [ 12 ]. However, cellulose derived from trees is still the most commonly investigated due to its high abundance and easy availability.…”