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Biodiscovery of Marine Microbial Enzymes in Indonesia
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Ekowati Chasanah, Pujo Yuwono, Dewi Seswita Zilda, Siswa Setyahadi
For decades, chitin has been well known as the second polymer, after cellulose, and is available in nature in an α or β form in the matrix with other materials such as protein and minerals. It can be found as a major structural component of arthropod exoskeleton and fungal cell walls, and the α-chitin form is being dominant. Commercial industries use chemical processes to obtain chitin, which is not considered environmentally friendly because they produce chemical waste. Environmentally friendly chitin production processes using lactic acid bacteria Lactobacillus acidophilus FNCC 116 to demineralize shrimp shells and deproteinize using Bacillus licheniformis F11.1 have been reported. Chitin produced by a biologically process has been reported to have a higher viscosity than that of chemically processed, which was more uncontrollable (Wahyuntari, Junianto, & Setyahadi, 2011). After chitin is obtained, derivative products from chitin that can be applied in various industries, namely, chitosan, chitooligosaccharides, chitin and chitosan, and the monomer, namely, glucosamine and N-acetyl glucosamine, can be produced using chitinolytic enzymes. The chitinolytic enzymes discussed in the following, namely, chitin deacetylase (CDA), chitinase, and chitosanase, are groups of enzymes that hydrolyze chitin and produce derivative products.
Targeted drug delivery strategy: a bridge to the therapy of diabetic kidney disease
Published in Drug Delivery, 2023
Xian Chen, Wenni Dai, Hao Li, Zhe Yan, Zhiwen Liu, Liyu He
Chitosan is a kind of polysaccharide derived from natural chitin which exists in the crustacean shells, fungal cell walls, arthropods and insects, with the properties of low toxicity, bioactivity, biocompatibility, biodegradability and structural variability (Kean and Thanou, 2010; Motiei et al., 2017).Chitosan can be degraded by chitosanase and lysozyme to form oligosaccharides and monosaccharides, and then absorbed by the body (Woraphatphadung et al., 2018). Chitosan stabilized nanoparticles (Ch-SeNPs) can downregulate the expression of TNF-α, IL-6, and IL-1β in type 2 DM rats, and Ch-SeNPs combine with metformin can reduce the creatine, proteinuria and urea (Khater et al., 2021). Researchers reported that chitosan oligosaccharides can ameliorate the proteinuria, reverse the kidney pathological changes, reduce the expression of TGF-β1 and fibronectin and the activity of urine N-acetyl-β-D-glucosaminidase (NAG) in STZ-T2DM rat model (Zhang et al., 2018).
An efficient enzyme-triggered controlled release system for colon-targeted oral delivery to combat dextran sodium sulfate (DSS)-induced colitis in mice
Published in Drug Delivery, 2021
Shangyong Li, Mengfei Jin, Yanhong Wu, Samil Jung, Dandan Li, Ningning He, Myeong-sok Lee
The purchased high molecular weight chitosan was dissolved in 1 M aqueous acetic acid (HAc) to a concentration of 1% (w/v) and chitosanase CsnM (20 U/mL) was added to colloidal chitosan at 20 °C for 10 min in a shaky condition. Low molecular weight unsaturated alginate was prepared by oligoalginate lyase OalC6 in our lab (Li et al., 2018). OalC6 (1 U) was added to 1 mL of high-viscosity sodium alginate polymer (5 mg/mL in 20 mM phosphate buffer, pH 7.0) and incubated at 40 °C for 60 min in a shaky condition. Then, these degrading products were heat-treated and dialyzed by a 1000 Da dialysis bag to remove smaller chitosan oligosaccharides (COS) or alginate oligosaccharides (AOS). The average molecular weight of prepared low molecular weight chitosan (8.76 kDa) and unsaturated alginate (7.73 kDa) were analyzed using viscosity methods (Li et al., 2019).
A novel vehicle for local protein delivery to the inner ear: injectable and biodegradable thermosensitive hydrogel loaded with PLGA nanoparticles
Published in Drug Development and Industrial Pharmacy, 2018
Juan Dai, Wei Long, Zhongping Liang, Lu Wen, Fan Yang, Gang Chen
Chitosan gel can be degraded by chitinases, chitosanases, and general lysozymes into chitosan oligomers and monomers and finally into a common amino sugar, N-acetylglucosamine which then enters the glycoprotein cycle and is eventually excreted as carbon dioxide [39]. In order to better simulate the degradation environment of gel in vivo, the in vitro enzymatic degradation of the gel was investigated. The degradation behavior of the CS/β-GP hydrogel in the presence of lysozyme was evaluated in PBS at 37 °C. Figure 5(A) shows that the CS/β-GP hydrogel can slowly degrade in vitro, with a weight loss of nearly 50% in a month. In vitro degradation was further confirmed by SEM. Figure 5(B) exhibits that the inner structures of hydrogel become thinner and looser with elapsed time, which favored free diffusion of water and drug molecules within the network. After being immersed in PBS containing lysozyme for a month, the gel matrix looked like fading leaves and the hydrogel structure almost collapsed. As evidenced by the above results, degradability contributed to the application of the hydrogel as vehicle in the treatment of inner ear disorders. Moreover, it is known to all that chitosanase specifically digests the chitosan matrix, and Lajud et al. evaluated the effectiveness of chitosanase digesting the chitosan glycerophosphate hydrogel in mouse model [6]. Consequently, the chitosanase can be administered to digest hydrogel if needed, and hydrogel matrix will not block the drug delivery of further dosage.