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Plant Source Foods
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Cellulose is a type of fiber called insoluble fiber comprised of long, linear polymers of hundreds of glucose molecules (polysaccharides), and plays an important role in human and animal digestion and nutrition (6, 9–10). These fibers aggregate into bundles of about 40, which are called micro-fibrils (6). In the diet, cellulose fibers are mainly present in green vegetables (stems, leaves), fruits, and whole grains. For humans, although cellulose is not digested, it plays important roles in digestion for health maintenance and disease prevention. Cellulose is used as a broom for the intestines, especially for the colon. Its benefits include helping food move through the digestive system more quickly, thus preventing constipation, and reducing the risk of developing a condition called diverticular disease (9–11). Cellulose or insoluble fibers can also bind toxins and cholesterol to avoid the risks of colon cancer development and cardiovascular diseases, and might reduce the risk of developing Type 2 diabetes (9–11). In industry, cellulose around the seeds of the cotton plants Gossypium has been used to make textiles since prehistoric times (2). Cellulose pulp obtained from wood or grasses is used to fabricate paper after pressing and drying processes. In trees, a secondary cell wall is constituted by a thicker additional layer of cellulose which increases wall rigidity. Both wood and bark cells of trees and leaf stalks have secondary walls (6, 9).
Potential Health and Nutraceutical Applications of Astaxanthin and Astaxanthin Esters from Microalgae
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Ambati Ranga Rao, Gokare A. Ravishankar
The life cycle of H. pluvialis comprises four stages: zoospores, microzooids, palmella and hematocysts (Elliot 1934). The zoospore, microzooid and palmella stages are called vegetative phases. Aplanospores are referred to as the red nonmotile astaxanthin accumulated encysted phase of the H. pluvialis life cycle. The zoospores are spherical ellipsoids which contain two flagella of equal length emerging from the anterior end and a cup-shaped chloroplast with numerous scattered pyrenoids. The zoospore cells are be tween 8 and 20 µm long with a distinct gelatinous extra-cellular matrix of variable thickness. The flagellated cells are major ones in the vegetative growth phase under favorable culture conditions. The macrozooids are divided into daughter cells by mitosis, and their cell size is stretched in unfavorable culture conditions (Wayama et al. 2013). The nonmotile palmella cells become the resting vegetative cells (Hagen et al. 2002). Palmella cells will turn into aplanospores under stress conditions such as high light intensity, high salinity and nutrient deficiency (Imamoglu et al. 2009). At this stage, cells contain a thick and rigid trilaminar sheath and a secondary cell wall of acetolysis-resistant material. Astaxanthin accumulates in the mature aplanospores and the lipid droplets deposited into the cytoplasm (Hagen et al. 2002). In some exceptional cases, it is reported that astaxanthin accumulates in H. pluvilias without forming aplanospores (Brinda et al. 2004). Under the optimal conditions, the red aplanospores turn into flagellated zoospores to initiate a new vegetative growth cycle.
Edible plant-derived nanotherapeutics and nanocarriers: recent progress and future directions
Published in Expert Opinion on Drug Delivery, 2022
Nanxi Chen, Jianfeng Sun, Zhenhua Zhu, Adam P. Cribbs, Bo Xiao
Moreover, a clear understanding of the composition of proteins in PDENs is expected to largely expand our knowledge as to how to beneficially use vesicles for local and systemic drug delivery. We list two examples below in which proteins enriched in PDENs have a beneficial influence on cellular activities. The first one starts from a common disease-causing phenomenon, oxidative stress, a key factor of inflammation activation and carcinogenesis. It can be suppressed by antioxidant enzymes to eliminate free radicals. Among the antioxidant enzymes, peroxidases that are extracted from PDENs can alleviate the oxidative stress in cells. The second example is given by the cell wall deposition protein, the Walls Are Thin1 protein (WAT1), which is involved in secondary cell wall deposition and resistance to the pathogen invasion. Altogether, the peroxidases and WAT1 can be identified based on the compositional analysis of proteins in Dendropanax morbifera-derived NPs and Pinus densiflora-derived NPs through searches against established databases using screened peptides obtained via mass spectrometry [43].
Engineered biomaterial strategies for controlling growth factors in tissue engineering
Published in Drug Delivery, 2020
Na Guan, Zhihai Liu, Yonghui Zhao, Qiu Li, Yitao Wang
Cellulose is the most abundant renewable polymer in nature, which is isolated from the secondary cell wall of plant cells, accounting for 20% ∼ 30% of the dry weight of plant cells (Rao et al., 2019). It plays a vital role in the field of functional foods. For instance, a variety of indigestible plant polysaccharides including cellulose, hemicelluloses, pectins, oligosaccharides, gums, were defined as the dietary fiber by the Food and Agriculture Organization (FAO). Among these, cellulose and hemicellulose can directly stimulate the bowel movement, which is the most widely spreading polymeric material in nature, is a fibrous, tough, water-insoluble material (Lynam et al., 2017; Xu et al., 2018). The basic unit of cellulose macromolecules is the glycan consisting of β-1, 4-glycoside bonds (Wang et al., 2016, 2018). Cellulose semi-synthetic derivatives are widely used in cosmetic and pharmaceutical fields, as well as used as dialysis membrane and biosensor (Amsden, 2015).
A mechanistic perspective on targeting bacterial drug resistance with nanoparticles
Published in Journal of Drug Targeting, 2021
Khatereh Khorsandi, Saeedeh Keyvani-Ghamsari, Fedora Khatibi Shahidi, Reza Hosseinzadeh, Simab Kanwal
Gram-positive bacterial cell walls, for example Bacillus anthracis, S. aureus, Streptococcus pneumoniae and Enterococcus faecalis are made of PGs. The PG layer acts as a supportive wall as well as a scaffold for connecting secondary cell wall polymers and surface proteins. The main secondary cell wall polymers contain the polyanionic wall teichoic acids (WTAs) and teichuronic acids, which bind to the PG layer, and lipoteichoic acids (LTAs), are fixed in the cytoplasmic membrane extended into the extracellular space [38,39]. The LTAs and WTAs are related to pathogenic virulence. LTAs such as lipid A, induce inherent immunity and WTAs are related to making biofilm, adhesion and resistance to antibiotics [39].