Separation, Purification, Structural Characterization, and Anticancer Activity of a Novel Exopolysaccharide from Mucor sp

Dextran produced by native strains isolated of Agave salmiana inhibits prostate and colon cancer cell growth

Biomaterials such as exopolysaccharides have been of great interest for their diverse biological activities in controlling or preventing chronic degenerative diseases, such as cancer. Previously, we isolated four dextrans produced by four strains isolated from Agave salmiana, which were named SF3, SF2, SD1, and SD23. The objective was to evaluate the antitumor activity of these dextrans on prostate (PC3) and colon (SW480) cancer cells. Growth inhibition, morphological changes, mitochondrial metabolism, and cell apoptosis were evaluated by sulforhodamine B, transmission electron microscopy, Seahorse XF and TUNEL assays, respectively. To gene expression was used qPCR and to protein ELISA and immunofluorescence. The cells treated with the dextrans to a dose of 8 mg/mL presented an inhibition of cell growth. Studies of the metabolism cell indicated a disruption in mitochondrial function and a diminished ability of the cells to respond to energy demands through glycolysis. These changes indicate mitochondrial damage resulting in oxidative stress or metabolic alterations. Survivin gen decreased and caspase-3 and -8 increased, key regulators of the apoptotic response with treatment. Moreover, the TUNEL assays indicated cell apoptosis. In conclusion, our findings suggest that dextrans could be considered as potential compounds for cancer treatment.

Revolutionizing cancer treatment: Harnessing the power of terrestrial microbial polysaccharides

Cancer treatment faces numerous challenges, such as inadequate drug targeting, steep price tags, grave toxic side effects, and limited therapeutic efficacy. Therefore, there is an urgent need for a safe and effective new drug to combat cancer. Microbial polysaccharides, complex and diverse biological macromolecules, exhibit significant microbial variability and uniqueness. Studies have shown that terrestrial microbial polysaccharides possess a wide range of biological activities, including immune enhancement, antioxidant properties, antiviral effects, anti-tumour potential, and hypoglycemic functions. To delve deeper into the structure-activity relationship of these land-based microbial polysaccharides against cancer, we conducted a comprehensive review and analysis of anti-cancer literature published between 2020 and 2024. The anticancer efficacy of terrestrial microbial polysaccharides is influenced by multiple factors, including the microbial species, existing form, chemical structure, and polysaccharide purity. According to the literature, an optimal molecular weight and good water solubility are essential for demonstrating anticancer activity. Furthermore, the addition of mannose and galactose has been found to significantly enhance the anticancer properties of these polysaccharides. These insights will serve as a valuable reference for future research and progress in the field of cancer drug therapy, particularly with regards to terrestrial microbial polysaccharides.

Advance in Hippophae rhamnoides polysaccharides: Extraction, structural characteristics, pharmacological activity, structure-activity relationship and application

Hippophae rhamnoides (Sea buckthorn) is an excellent medicinal and edible plant owing to its high nutritional and health-promoting properties. As an important bioactive component, H. rhamnoides polysaccharides (HRPs) have aroused wide attention due to their various pharmacological activities, including hepatoprotective, immuno-modulatory, anti-inflammatory, anti-oxidant, anti-tumor, hypoglycemic, anti-obesity, and so on. Nevertheless, the development and utilization of HRP-derived functional food and medicines are constrained to a lack of comprehensive understanding of the structure-activity relationship, application, and safety of HRPs. This review systematically summarizes the advancements on the extraction, purification, structural characteristics, pharmacological activities and mechanisms of HRPs. The structure-activity relationship, safety evaluation, application, as well as the shortcomings of current research and promising prospects are also highlighted. This article aims to offer a comprehensive understanding of HRPs and lay a groundwork for future research and utilization of HRPs as multifunctional biomaterials and therapeutic agents.

Microbial exopolysaccharides: Unveiling the pharmacological aspects for therapeutic advancements

Microbial exopolysaccharides (EPSs) have emerged as a fascinating area of research in the field of pharmacology due to their diverse and potent biological activities. This review paper aims to provide a comprehensive overview of the pharmacological properties exhibited by EPSs, shedding light on their potential applications in various therapeutic areas. The review begins by introducing EPSs, exploring their various sources, significance in microbial growth and survival, and their applications across different industries. Subsequently, a thorough examination of the pharmaceutical properties of microbial EPSs unveils their antioxidant, immunomodulatory, antimicrobial, antidepressant, antidiabetic, antiviral, antihyperlipidemic, hepatoprotective, anti-inflammatory, and anticancer activities. Mechanistic insights into how different EPSs exert these therapeutic effects have also been discussed in this review. The review also provides comprehensive information about the monosaccharide composition, backbone, branches, glycosidic bonds, and molecular weight of pharmacologically active EPSs from various microbial sources. Furthermore, the factors that can affect the pharmacological activities of EPSs and approaches to improve the EPSs' pharmacological activity have also been discussed. In conclusion, this review illuminates the immense pharmaceutical promise of microbial EPS as versatile bioactive compounds with wide-ranging therapeutic applications. By elucidating their structural features, biological activities, and potential applications, this review aims to catalyze further research and development efforts in leveraging the pharmaceutical potential of microbial EPS for the advancement of human health and well-being, while also contributing to sustainable and environmentally friendly practices in the pharmaceutical industry.

Exopolysaccharide from Lactococcus hircilactis CH4 and Lactobacillus delbrueckii GRIPUMSK as new therapeutics to treat biofilm pathogens, oxidative stress and human colon adenocarcinoma

Naturally occurring biopolymers like exopolysaccharides (EPS) secreted by lactic acid bacteria (LAB) has gained significant attention as they are cost effective, renewable and safe. In order to prevent the rapid increase in antibiotic resistant bacteria, the EPS of LAB offers novel approach of targeting the antibiotic resistant pathogens by limiting their effects on environment. Accordingly, in this study, the production, purification, characterization and biological properties of exopolysaccharides from Lactococcus hircilactis strain CH4 and Lactobacillus delbrueckii strain GRIPUMSK were performed. The optimization of lactic acid bacterial strains for exopolysaccharide production was done by response surface methodology and changing the carbon sources in the growth media. The carbohydrate and protein of exopolysaccharide 1 were 79.7 % and 8.7 % respectively and exopolysaccharide 2 were 75.2 % and 9.3 % respectively. When compared with the commercial emulsifier sodium dodecyl sulfate, both the exopolysaccharides have shown good emulsifying activity. Both the exopolysaccharides were linear homo-polysaccharide as determined by Fourier transform infrared spectroscopy and Nuclear magnetic resonance spectra. Scanning electron microscopy showed that the exopolysaccharides were porous and capable of holding water. The exopolysaccharides were partially crystalline as confirmed by X-ray diffraction spectra. Exopolysaccharides from L. hircilactis and L. delbrueckii exhibited significant antimicrobial activity against H. pylori, S. flexneri, S. pyogenes, E. faecalis and C. albicans. Both the exopolysaccharides revealed significant 2,2-diphenyl-1-picrylhydrazyl and hydrogen peroxide scavenging ability with the IC50 value of 100 μg/ml and 80 μg/ml respectively. Exopolysaccharides from L. hircilactis and L. delbrueckii at 100 μg/ml showed significant anticancer activity on HT-29 cells with 58.4 % and 58.7 % respectively. These findings proved that exopolysaccharides from the two selected lactic acid bacterial strains could be explored as natural bioactive carbohydrate polymer for biomedical applications.

Rhizoctonia solani AG1 IA extracellular polysaccharides: Structural characterization and induced resistance to rice sheath blight

Sheath blight, caused by Rhizoctonia solani (R. solani), is one of the most serious diseases of rice. Extracellular polysaccharides (EPS) are complex polysaccharides secreted by microbes that have a pivotal role in the plant-microbe interaction. At present, many studies have been carried out on R. solani, but it is not very clear whether the EPS is secreted by R. solani exists. Therefore, we isolated and extracted the EPS from R. solani, two kinds of EPS (EW-I and ES-I) were obtained by DEAE-cellulose 52 and Sephacryl S-300HR column further purification, and their structures were characterized by FT-IR, UV, GC, and NMR analysis. The results showed that EW-I and ES-I had similar monosaccharide composition but different molar ratio, they were composed of fucose, arabinose, galactose, glucose, and mannose with a ratio of 7.49: 27.72: 2.98: 6.66: 55.15 and 3.81: 12.98: 6.15: 10.83: 66.23, and their backbone may be composed of →2)-α-Manp-(1→ residues, beside ES-I was highly branched compared to EW-I. The exogenous application of EW-I and ES-I had no effect on the growth of R. solani AG1 IA itself, but their pretreatment of rice induced plant defense through activation of the salicylic acid pathway, resulting in enhanced resistance to sheath blight.

First report on isolation of Mucor bainieri from honeybees, Apis mellifera: Characterization and biological activities

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The schematic mechanism for R1234yf combustion were revealed in unimolecular lysis reactions, colliding reactions with oxygen molecules, collision reaction with active radicals (H and OH radicals).

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The new chemical reaction equations for the combustion of R1234yf were proposed.

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This paper provided an effective method to establish the combustion mechanism of flammable hydrofluoroolefins.

Fungi are potential biocontrol agents and rich sources of secondary metabolites with demonstrated biological activities. This study aimed to isolate and identify fungi from surface-sterilized honeybees (Apis mellifera), as well as to evaluate their biological activities. One fungal isolate was obtained and identified morphologically and genetically as Mucor bainieri MK-Bee-2. Gas chromatography-mass spectroscopy (GC–MS) analysis of fungus crude extract, showed the existence of six major metabolites representing 92.48% of the total peak area. The crude extract of Mucor bainieri MK-Bee-2 was tested for antimicrobial, antioxidant, and antitumor activities. It demonstrated wide antimicrobial activities against human pathogenic Gram-positive and Gram-negative bacterial strains, as well as Candida albicans, with MIC values ranged from 62.5 to 250 µg/ml. The results revealed that the extract exhibited considerable antioxidant activities indicated by strong inhibition of both DPPH and ABTS free radicals. Additionally, the extract exhibited greater potential anticancer activity against both adenocarcinomic human non-small cell lung cancer cells (A549) [IC₅₀ = 6.45 μg/ml], and immortal cell line hepatoma G2 (HepG2) human liver cancer cells [IC₅₀ = 27.48 μg/ml] and higher selectivity in cancer cells than normal cell lines. Furthermore, the extract showed less cytotoxic activity against normal cells with higher IC₅₀ values of 106.99 and 132.57 μg/ml against human lung fibroblast Wistar-38 (Wi-38) and oral epithelial cells (OEC), respectively. Taken together, the Mucor bainieri MK-Bee-2 extract comprises bioactive compounds as promising potential therapeutic candidates for the treatment of lung cancer. Strikingly, the extract sensitizes the lung cancer cells A549  to the ionizing radiation through the pro-apoptotic pathway as indicated by the annexin V flow cytometry analysis which showed that the extract reduced the apoptosis of lung cancer cells.