Seaweed-Derived Sulfated Polysaccharides; The New Age Chemopreventives: A Comprehensive Review

Seaweed-derived bioactive compounds are regularly employed to treat human diseases. Sulfated polysaccharides are potent chemotherapeutic or chemopreventive medications since it has been discovered. They have exhibited anti-cancer properties by enhancing immunity and driving apoptosis. Through dynamic modulation of critical intracellular signalling pathways, such as control of ROS generation and preservation of essential cell survival and death processes, sulfated polysaccharides' antioxidant and immunomodulatory potentials contribute to their disease-preventive effectiveness. Sulfated polysaccharides provide low cytotoxicity and good efficacy therapeutic outcomes via dynamic modulation of apoptosis in cancer. Understanding how sulfated polysaccharides affect human cancer cells and their molecular involvement in cell death pathways will showcase a new way of chemoprevention. In this review, the significance of apoptosis and autophagy-modulating sulfated polysaccharides has been emphasized, as well as the future direction of enhanced nano-formulation for greater clinical efficacy. Moreover, this review focuses on the recent findings about the possible mechanisms of chemotherapeutic use of sulfated polysaccharides, their potential as anti-cancer drugs, and proposed mechanisms of action to drive apoptosis in diverse malignancies. Because of their unique physicochemical and biological properties, sulfated polysaccharides are ideal for their bioactive ingredients, which can improve function and application in disease. However, there is a gap in the literature regarding the physicochemical properties and functionalities of sulfated polysaccharides and the use of sulfated polysaccharide-based delivery systems in functional cancer. Furthermore, the preclinical and clinical trials will reveal the drug's efficacy in cancer.

Structure and Bioactivities of Porphyrans and Oligoporphyrans

BACKGROUND

Pyropia (Porphyra), commonly known as nori or laver, is an important food source in many parts of the world. Edible dried Pyropia contains numerous nutrients and biofunctional components, including proteins, vitamins, eicosapentaenoic acid, minerals, carotenoids, mycosporine-like amino acids, and carbohydrate, and one of the compounds which we are interested in is porphyran, a sulfated polysaccharide comprising the hot-water-soluble portion of Pyropia cell walls. Researchers have performed a large number of in-depth studies on the biological activity and potential therapeutic applications of porphyrans and oligoporphyrans.

METHODS

This mini review aims to provide comprehensive and update overview on the source, extraction, structure, biological activities and structure-activity relationships of porphyrans and oligoporphyrans based on the studies in the past 30 years which were included in Web of Science.

RESULTS

The structure of porphyran has been basically determined given that its straight chain is relatively simple, and the skeleton structure has been described. The extraction methods were simplified continuously, but different extraction methods and post- processing methods still had great influence on the structure and composition of porphyran, so there was no standardized extraction process which can achieve quality control until now. In order to obtain oligoporphyrans, there are a variety of degradation methods, including chemical method, physical method and enzymatic method, but it is worth mentioning that specific degradation enzyme is still unavailable. Studies on the biological and pharmacology properties include antioxidant, anti-tumor, anti-inflammatory, immunomodulation, anti-cardiovascular and cerebrovascular diseases and drug delivery.

CONCLUSION

Owing to the therapeutic potential and drug delivery applications, porphyran and oligoporphyrans are expected to be further developed as a medicine against human diseases, as well as a supplement in cosmetics and health products.

Anti-Cancer Activity of Porphyran and Carrageenan from Red Seaweeds

Seaweeds are some of the largest producers of biomass in the marine environment and are rich in bioactive compounds that are often used for human and animal health. Porphyran and carrageenan are natural compounds derived from red seaweeds. The former is a characteristic polysaccharide of Porphyra, while the latter is well known from Chondrus, Gigartina, and various Eucheuma species, all in Rhodophyceae. The two polysaccharides have been found to have anti-cancer activity by improving immunity and targeting key apoptotic molecules and therefore deemed as potential chemotherapeutic or chemopreventive agents. This review attempts to review the current study of anti-cancer activity and the possible mechanisms of porphyran and carrageenan derived from red seaweeds to various cancers, and their cooperative actions with other anti-cancer chemotherapeutic agents is also discussed.

Identification of Bacillus cereus in a chungkukjang that showed high anticancer effects against AGS human gastric adenocarcinoma cells

Anticancer effects of chungkukjang (a Korean short-term fermented soy paste) were studied in human gastric adenocarcinoma cells, and Bacillus strains from chungkukjang were isolated and identified. Before the experiments, six different chungkukjang products (K-, M-, Mn-, O-, Os-, and H-chungkukjangs) were purchased from a folk village in the Sunchang region, Jeonbuk, Republic of Korea. Based on sensory evaluation tests and general chemical and quality studies, K-, H-, and M-chungkukjangs were selected for the experiments. All chungkukjang samples exhibited in vitro anticancer activities; however, K-chungkukjang revealed the highest anticancer activity in the previous studies. In this experiment, K-chungkukjang again showed the highest anticancer effect in the AGS cells. At the concentration of 1 mg/mL, K-chungkukjang (87%) showed the highest growth inhibitory effect, followed by H-chungkukjang (85%) and MC-chungkukjang (69%) (P < .05). K-chungkukjang induced apoptosis as determined by 4,6-diamidino-2-phenylindole staining and exhibited increased bax and decreased bcl-2 mRNA expression. Three representative Bacillus strains from K-chungkukjang were isolated and identified by recA gene sequencing as Bacillus cereus, Bacillus amyloliquefaciens, and Bacillus subtilis. Identifying B. cereus in the chungkukjang means that when chungkukjang is prepared by the traditional method, B. cereus, which is a common cause of foodborne disease, can grow during the natural fermentation process. All B. cereus strains, of course, are not pathogens, but its presence causes food safety concerns. Therefore, using a starter culture is safer than the traditional natural fermentation for the industrialization of chungkukjang in Korea.