Preparation of Cellulose Nanoparticles from Foliage by Bio-Enzyme Methods

Abstract

There are vast reserves of foliage in nature, which is an inexhaustible precious resource. In this study, the chemical components of five foliage types (pine needles, black locust tree leaves, bamboo leaves, elm leaves and poplar leaves) were analyzed, including cellulose content, hemicellulose content, and lignin content. The bio-enzymatic method was then used to prepare cellulose nanoparticles (CNPs) from these five kinds of leaves, and the prepared CNPs were analyzed using TEM, FTIR, FESEM, and XRD. The results showed that the content of hemicellulose in bamboo leaves was the highest, and the lignin content in the other four leaves was the highest. The cellulose content in the five kinds of foliage was arranged from large to small as pine needles (20.5%), bamboo leaves (19.5%), black locust leaves (18.0%), elm leaves (17.6%), and poplar leaves (15.5%). TEM images showed that the CNPs prepared by the five kinds of foliage reached the nanometer level in width and the micrometer level in length; therefore, the CNPs prepared in this study belonged to cellulose nanofibers (CNFs). The results of FTIR and XRD showed that CNFs prepared by the enzyme treatment exhibited a typical crystalline structure of cellulose II. The degree of crystallinity (DOC) of CNFs prepared from pine needle, poplar leaves, and bamboo leaves are 78.46%, 77.39%, and 81.51%, respectively. FESEM results showed that the CNFs prepared from pine needles, poplar leaves and bamboo leaves by enzymatic method presents a three-dimensional (3D) network structure, and their widths are 31 nm, 36 nm, and 37 nm, respectively. This study provides a meaningful reference for broadening the use of foliage types and improving their added value.

Preparation and characterization of nanocellulose fiber (CNF) by biological enzymatic method

“…No peak was observed at around 1500 cm À1 due to the vibration of the aromatic skeleton in the lignin plane, and no peak was observed at around 1740 cm À1 due to hemicellulose. [27][28][29][30][31][32][33][34][35] These results show that cellulose can be extracted from SJ, CF and PY by both CM1 and BM2, and there is almost no residual lignin or hemicellulose. Moreover, the peak strength of cellulose prepared by BM2 at 3400 cm À1 , 1060 cm À1 , 890 cm À1 is significantly higher than that prepared by chemical method and might be associated with the crystallinity of the samples.…”

Study on the effects of different pectinase/cellulase ratios and pretreatment times on the preparation of nanocellulose by ultrasound-assisted bio-enzyme heat treatment

“…Nanocellulose was prepared by pretreatment with bio-enzymes. 28 First, an aqueous solution containing 5% (mass ratio) cellulase and 5% (mass ratio) pectinase was prepared. About 0.5 g MCC was placed in a beaker containing 20 g zirconia grinding beads (0.1 mm diameter) and a magnetic stirrer.…”

Antibacterial Films Made of Bacterial Cellulose

“…A 1.5% solution of a given film was prepared by adding 98.5 mL distilled water, 1.5 g CMBC or CMC in a heated magnetic mixer at 900-1000 rpm at 45 • C. When the CMC was completely dissolved in water, 0.8 g of sodium alginate and 0.25 g of glycerin were added and stirred until the mixture was uniform, then the temperature was raised to 70 • C until the sodium alginate and glycerin were entirely dissolved, a further 4.5 mg of Rose essential oil, Cumin essential oil, Nano-silver (Nano-Ag, particle diameter of 60-80 nm), nano-silica dioxide (Nano-SiO 2 , particle diameter of 30 ± nm), nano-titanium dioxide (Nano-TiO 2 , particle diameter of 25 ± nm), or 0.58 g nano-bacterial cellulose (nano-BC, particle diameter of 40 ± nm) solution (prepared by biological enzymes and mechanical mixing in Lab of Yunnan Key Laboratory of Wood Adhesives and Glue Products, with a solid content of 0.26% [13]) were added, then the film solution was placed in an ultrasonic cleaner at 50 Hz for 12 min to remove the air bubbles. The solution (Figure 1G) was then cast on a PTFE mold and dried at 30 • C for 48 h (Figure 1H,I).…”