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Marine-Based Carbohydrates as a Valuable Resource for Nutraceuticals and Biotechnological Application
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Rajni Kumari, V. Vivekanand, Nidhi Pareek
Laminarin is a brown algae–based sulfated polysaccharides with a low molecular weight (~5 kDa). It is present in cell walls of Saccharina and Laminaria and to some extent in Fucus and Ascophyllum species, and it serves as the main carbohydrate reserve of brown algae species (Kraan, 2012; Kadam et al., 2014). Laminarin is the first discovered species of Saccharina and Laminaria—nowadays it is known as the most abundant source of carbon for marine ecosystems (Sanjeewa et al., 2017). Typically, laminarin accounts for up to 35% of the dry weight of algae. However, the percentage of laminarin in these algae depends on several factors such as algae species, extraction method, habitat, and harvest season.
Bioactive Compounds in Marine Macro Algae and Their Role in Pharmacological Applications
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
Subramaniam Kalidass, Lakshmanan Ranjith, Palavesam Arunachalam, Amarnath Mathan Babu, Karuppasamy Kaviarasan
Laminarin is primarily formed of (1,3)-β-d-glucan with β (1, 6) branching (Rioux et al. 2007). Moreover, it is classified into two types of laminarin chains with mannitol and glucose, and their molecular weight is about 5000 Da. In brown algae, the laminarin content is up to 35% on a dry basis that varies depending on the species. Potential pharmacological activities are found in laminarin, for instance, anti-tumor, anti-oxidant, and anti-inflammatory activity (Ren et al. 1994; Hoffman et al. 1995; Miao et al. 1999).
Marine Bioactive Compounds: Innovative Trends in Food and Medicine
Published in Megh R. Goyal, Durgesh Nandini Chauhan, Plant- and Marine-Based Phytochemicals for Human Health, 2018
Munawar Abbas, Farhan Saeed, Hafiz Ansar Rasul Suleria
Marine algae are the richest source of antioxidants among natural sources.44 The function of sulfated polysaccharides (SPs) from algae not only provides dietary fiber, but it also subsidizes as antioxidant in marine life. Fucoidans, laminaran, and alginic acid have high antioxidant activities.59 The antioxidant activity of SPs has been investigated by different methods such as DPPH radical scavenging, lipid peroxide inhibition, NO scavenging, super oxide radical, and hydroxyl scavenging assays. By the function, many marine-derived SPs have their antioxidant properties in phosphatidylcholine-liposomal suspension and an organic solvent such as acetone, methyl acetate, and toluene.4 The dependence of antioxidants is on structural features as the degree of sulfating, molecular weight, and the type of major sugar. For example, the lower molecular weighted SPs show potent antioxidant activities than that of the higher weighted SPs.
The vital role of animal, marine, and microbial natural products against COVID-19
Published in Pharmaceutical Biology, 2022
Aljawharah A. Alqathama, Rizwan Ahmad, Ruba B. Alsaedi, Raghad A. Alghamdi, Ekram H. Abkar, Rola H. Alrehaly, Ashraf N. Abdalla
Other studies revealed that a phlorotannins isolated from edible brown algae Ecklonia cava (Kjellman, Lessoniaceae), named dieckol and eckol, exhibited the highest suppression rates of SARS-CoV 3CLprotrans/cis-cleavage and the lowest binding energy to 3 CLpro (–11.51 kcal/mol, –8.19 kcal/mol), respectively (Park et al. 2013; Arunkumar et al. 2021). One of the dieckol derivatives (DK70) has been proven to interfere with RBD–hACE2 interaction as it displayed good binding affinity with RBD. Furthermore, DK70 forms a stable complex with RBD due to the formation of hydrogen bonds, electrostatic and hydrophobic interactions, that are considered as residues mediating the hACE2–RBD interaction (Aatif et al. 2021). Trifucol is another phlorotannin obtained from the brown alga Himanthalia elongata ((Linnaeus) S.F. Grey,\Himanthaliaceae) and targets the S-glycoprotein (–7.5 kcal/mol) and 3CLpro (–6.3 kcal/mol), respectively (Arunkumar et al. 2021). Different polysaccharides such as glycosaminoglycan from different marine species and bacteria, Pseudomonas sp., (Pseudomonadaceae) and laminarin from brown marine algae like Laminaria digitata ((Huds.) Lamouroux., Laminariaceae) are reported with Mpro higher binding energy at –7.98 kcal/mol and –7.81 kcal/mol, respectively (Vijayaraj et al. 2020; Arunkumar et al. 2021).
Linear and branched β-Glucans degrading enzymes from versatile Bacteroides uniformis JCM 13288T and their roles in cooperation with gut bacteria
Published in Gut Microbes, 2020
Ravindra Pal Singh, Sivasubramanian Rajarammohan, Raksha Thakur, Mohsin Hassan
Surprisingly, B. producta JCM 1471 T showed strong growth on β-1, 3-OSs in co-culture condition (Figure 6(a)). Although, it did not independently grow well on laminarin. Genomic evidence suggests that it has homologous genes to BuGH3, BuGH30_3 and BuGH16 (Supplementary Table S2). In addition, it has a gene coding for putative laminarin phosphorylase. The signalP-5.0 predicted that only BPGH16 is present at the outer membrane that is likely to convert polysaccharide in to oligosaccharides before its import into the cytoplasm. In order to check possibility to cleave β-1, 6 linked glucan, we cloned a best heat gene (JGI-IMG – protein ID- 2515950412, homologous to BuGH30_3) but it did not cleave any tested substrates (Supplementary Fig. S10), suggesting that it might be not cleaving branch chain of β-1, 6 linked glucan. To the best of our knowledge, this is the first evidence to suggest that human gut Gram-positive bacteria can have β-1, 3 linked glucan digesting gene cluster.
A review of stimuli-responsive polymeric micelles for tumor-targeted delivery of curcumin
Published in Drug Development and Industrial Pharmacy, 2021
Na Qiu, Xiyou Du, Jianbo Ji, Guangxi Zhai
pH-sensitive PCL-PDEA and redox-sensitive mPEG-SS-PCL copolymers were prepared and used at a mass ratio of 5: 5 in solvent evaporation method to prepare the dual-sensitive (pH-redox responsive) micelles through hydrophobic interactions between the two copolymers, and then Cur was successfully encapsulated (EE = 89.86%, DL = 8.3%). The diameter and distribution of the mixed micelles were measured by dynamic light scattering (DLS) before and after the pH change to confirm pH sensitivity of the mixed micelles. The morphological changes of the micelles before and after adding DTT were observed by scanning electron microscopy (SEM) to confirm reduction sensitivity of the micelles. The results of in vitro drug release experiments showed the highest cumulative release and rate of release under reductive conditions of low pH by mixed micelles compared with other experimental groups, confirming pH and redox sensitivity of drug-loaded mixed micelles. Moreover, drug-loaded mixed micelles exhibited maximum cytotoxicity in HeLa cells, while blank micelles were almost nontoxic [126], as assessed by the MTT assay. Laminarin is an excellent marine biological material with low adhesion, good water solubility, and oxidation resistance. Moreover, sulfated laminarin can inhibit the growth of blood vessels in the tumor lesion and reduce the diffusion of tumor derivatives. Based on these studies, Yu et al. synthesized a chemical structure called Hematin-Laminarin-Dithiodipropionic Acid-MGK (HLDM) with a pH-sensitive ketone structure and reduction-sensitive disulfide bonds. In addition, hematin is a photosensitizer that can produce ROS. HLDM self-assembled in water to form micelles effectively encapsulated Cur. In this study, Cur-loaded HLDM micelles with pH/redox sensitivity (MGK/dithiodipropionic acid) also exhibited a PDT feature. Under environmental conditions of pH 5.6 + GSH 10 mM, Cur-HLDM showed better cumulative release and faster release rate than other groups. In addition, cell experiments showed stronger cellular uptake of Cur-HLDM with higher cytotoxicity in MCF-7 cells than free Cur. Cur-HLDM can be used as a novel tumor-targeted DDS with dual pH/redox sensitivity [127]. Table 2 lists some multi-stimulus-responsive micellar systems.