(1→3)-β-D-Glucan inhibits a dual mechanism of peroxynitrite stroke

Potential for curdlan recovery from aerobic granular sludge wastewater treatment systems - A review

The aerobic granular sludge (AGS) biotechnology has been explored for wastewater treatment for over two decades. AGS is gaining increased interest due to its enhanced treatment performance ability and the potential for resource recovery from AGS-based wastewater treatment systems. Resource recovery from AGS is a promising approach to sustainable wastewater treatment and attaining a circular economy in the wastewater management industry. Currently, research is at an advanced stage on recovering value-added resources such as phosphorus, polyhydroxyalkanoates, alginate-like exopolysaccharides, and tryptophan from waste aerobic granules. Recently, other value-added resources, including curdlan, have been identified in the aerobic granule matrix, and this may increase the sustainability of biotechnology in the wastewater industry. This paper provides an overview of AGS resource recovery potential. In particular, the potential for enhanced curdlan biosynthesis in the granule matrix and its recovery from AGS wastewater treatment systems is outlined.

Therapeutic and Industrial Applications of Curdlan With Overview on Its Recent Patents

Curdlan is an exopolysaccharide, which is composed of glucose linked with β-(1,3)-glycosidic bond and is produced by bacteria, such as Alcaligenes spp., Agrobacterium spp., Paenibacillus spp., Rhizobium spp., Saccharomyces cerevisiae, Candida spp., and fungal sources like Aureobasidium pullulan, Poria cocos, etc. Curdlan has been utilized in the food and pharmaceutical industries for its prebiotic, viscosifying, and water-holding properties for decades. Recently, the usefulness of curdlan has been further explored by the pharmaceutical industry for its potential therapeutic applications. Curdlan has exhibited immunoregulatory and antitumor activity in preclinical settings. It was observed that curdlan can prevent the proliferation of malarial merozoites in vivo; therefore, it may be considered as a promising therapy for the treatment of end-stage malaria. In addition, curdlan has demonstrated potent antiviral effects against human immunodeficiency virus (HIV) and Aedes aegypti virus. It has been suggested that the virucidal properties of curdlans should be extended further for other deadly viruses, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and the current severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2/COVID-19). The prebiotic property of curdlan would confer beneficial effects on the host by promoting the growth of healthy microbiota in the gut and consequently help to reduce gastrointestinal disorders. Therefore, curdlan can be employed in the manufacture of prebiotics for the management of various gastrointestinal dysbiosis problems. Studies on the mechanism of action of curdlan-induced suppression in microbial and tumor cells at the cellular and molecular levels would not only enhance our understanding regarding the therapeutic effectiveness of curdlan but also help in the discovery of new drugs and dietary supplements. The primary focus of this review is to highlight the therapeutic interventions of curdlan as an anticancer, anti-malaria, antiviral, and antibacterial agent in humans. In addition, our review provides the latest information about the chemistry and biosynthesis of curdlan and its applications for making novel dairy products, functional foods, and nutraceuticals and also details about the recent patents of curdlan and its derivatives.

β-Glucans as a panacea for a healthy heart? Their roles in preventing and treating cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Factors increasing the risks for CVD development are related to obesity, diabetes, high blood cholesterol, high blood pressure and lifestyle. CVD risk factors may be treated with appropriate drugs, but prolonged can use cause undesirable side-effects. Among the natural products used in complementary and alternative medicines, are the β-ᴅ-glucans; biopolymers found in foods (cereals, mushrooms), and can easily be produced by microbial fermentation. Independent of source, β-glucans of the mixed-linked types [(1 → 3)(1 → 6)-β-ᴅ-glucans - fungal, and (1 → 3)(1 → 4)-β-ᴅ-glucans - cereal] have widely been studied because of their biological activities, and have demonstrated cardiovascular protective effects. In this review, we discuss the roles of β-ᴅ-glucans in various pathophysiological conditions that lead to CVDs including obesity, dyslipidemia, hyperglycemia, oxidative stress, hypertension, atherosclerosis and stroke. The β-glucans from all of the sources cited demonstrated potential hypoglycemic, hypocholesterolemic and anti-obesogenicity activities, reduced hypertension and ameliorated the atherosclerosis condition. More recently, β-glucans are recognized as possessing prebiotic properties that modulate the gut microbiome and impact on the health benefits including cardiovascular. Overall, all the studies investigated unequivocally demonstrated the dietary benefits of consuming β-glucans regardless of source, thus constituting a promising panaceutical approach to reduce CVD risk factors.

Protective effects of beta glucan in brain tissues of post-menopausal rats: a histochemical and ultra-structural study

Decline of estrogen during menopause has been associated with numerous significant changes that have been linked to many pathophysiological complications. In addition, ovarian hormone deficiency increases the production of reactive oxygen radicals which could result in oxidative stress and cell damage. While estrogen therapy is often considered to overcome the behavioral and physiological shortcomings, antioxidants are gaining popularity for their beneficial property. For this purpose, in the present study, utilizing the antioxidant properties of beta glucan has been examined in treatment of menopause induced oxidative stress in cerebral neurons. Four groups of female Wistar rats were used: control, ovariectomy, ovariectomy + estrogen treated and ovariectomy + beta glucan treated. We observed a significant increase in neural degeneration in ovariectomized rats as compared to controls. Moreover, increased oxidative stress in the brains of the ovariectomized rats has been detected by performing immunohistochemical analysis. A large number of immuno-positive cerebral neurons have been observed in ovariectomy group rat brains. Interestingly, providing beta glucan treatment to ovariectomized rats reduced the number of degenerated neurons. Our study is the first to examine light and electron microscopic examination and immunohistochemical and stereological analysis of estrogen depletion in rats and to test protective role of beta glucan in the experimental study.

Antitumor activity of the β-glucan paramylon from Euglena against preneoplastic colonic aberrant crypt foci in mice

In the present study, the effects of β-glucans isolated from Euglena on the formation of preneoplastic aberrant crypt foci (ACF) in the colon were examined in mice. Mice were fed a semi-purified AIN-93M diet containing cellulose or the same diet but with the cellulose replaced with β-glucans in the form of Euglena, paramylon, or amorphous paramylon, for 11 weeks. After consuming these dietary supplements for 8 days, half of the mice were intraperitoneally administered 1,2-dimethylhydrazine (DMH) at a dose of 20 mg kg(-1) body weight every week for 6 weeks. Among the DMH-treated groups, the paramylon- and amorphous paramylon-fed mice displayed a significantly lower number of ACF than the control group. Also, the liver weight of the paramylon group was markedly decreased compared with those of the control and Euglena groups, whereas the cecal content weight and fecal volume of the paramylon group were significantly increased. As for the levels of organic acids in the cecal contents, the paramylon group displayed significantly increased lactic acid levels compared with the control and Euglena groups. From these findings, although the mechanism of the ACF-inhibiting effects of paramylon remains unclear, it is considered that β-glucans, such as paramylon and its isomer amorphous paramylon, have preventive effects against colon cancer and are more effective against the condition than Euglena.

(1→3)-β-D-Glucan reduces the damages caused by reactive oxygen species induced in human platelets by lipopolysaccharides

LPS (lipopolysaccharide) induces platelet activation and is a well-known fundamental agent of septic shock and disseminated intravascular coagulation (DIC). Biological activity of (1→3)-β-D-glucan is related due to its anti-inflammatory, antioxidant, and antitumor properties. We focus our attention on the (1→3)-β-D-glucan (antiplatelet) properties. The main purpose of our study was to evaluate the influence of (1→3)-β-D-glucan from Saccharomyces cerevisiae on destructive activity of LPS (from Escherichia coli and Pseudomonas aeruginosa) on human blood platelets. We assess biochemically in vitro if (1→3)-β-D-glucan might combat the oxidative stress caused by LPS stroke associated with nitrative and oxidative damages of human platelet biomolecules. We also make an attempt by in silico molecular docking to determine the interactions between the molecules of (1→3)-β-D-glucan and LPS. Our conclusion is that protective mechanism of (1→3)-β-D-glucan against LPS action on blood platelets is due to as well: its antioxidant properties, as to its interaction with LPS-binding region of TLR4-MD-2 complex.

Protective effects of beta glucan and gliclazide on brain tissue and sciatic nerve of diabetic rats induced by streptozosin

There have not been yet enough studies about effects of beta glucan and gliclazide on oxidative stress created by streptozotocin in the brain and sciatic nerve of diabetic rats. The aim of this paper was to investigate the antioxidant effects of gliclazide and beta glucan on oxidative stress and lipid peroxidation created by streptozotosin in brain and sciatic nerve. Total of 42 rats were divided into 6 groups including control, diabetic untreated (DM) (only STZ, diabetic), STZ (DM) + beta glucan, STZ (DM) + gliclazide, only beta glucan treated (no diabetic), and only gliclazide treated (no diabetic). The brain and sciatic nerve tissue samples were analyzed for malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and paraoxonase (PON-1) levels. We found a significant increase in MDA, TOS, and OSI along with a reduction in TAS level, catalase, and PON-1 activities in brain and sciatic nerve of streptozotocin-induced diabetic rats. Also, this study shows that in terms of these parameters both gliclazide and beta glucan have a neuroprotective effect on the brain and sciatic nerve of the streptozotocin-induced diabetic rat. Our conclusion was that gliclazide and beta glucan have antioxidant effects on the brain and sciatic nerve of the streptozotocin-induced diabetic rat.

Beta-glucan from Saccharomyces cerevisiae reduces plasma lipid peroxidation induced by haloperidol

Since oxidative stress observed in schizophrenia may be caused partially by the treatment of patients with various antipsychotics, the aim of the study was to establish the effects of beta-d-glucan, polysaccharide derived from the yeast cell walls of species such as Saccharomyces cerevisiae, and the antipsychotics (the first generation antipsychotic (FGA) - haloperidol and the second generation antipsychotic (SGA) - amisulpride) action on plasma lipid peroxidation in vitro. Lipid peroxidation in human plasma was measured by the level of thiobarbituric acid reactive species (TBARS). The samples of plasma from healthy subjects were incubated with haloperidol or amisulpride in the presence of beta-glucan (4 μg/ml). The action of beta-d-glucan was also compared with the properties of a well characterized commercial monomeric polyphenol - resveratrol (3,4',5-trihydroxystilbene, the final concentration - 4 μg/ml). The two-way analysis variance showed that the differences in TBARS levels were depended on the type of tested drugs (p=7.9 × 10(-6)). We observed a statistically increase of the level of biomarker of lipid peroxidation such as TBARS after 1 and 24h incubation of plasma with haloperidol compared to the control samples (p<0.01, p<0.02, respectively). Amisulpride, contrary to haloperidol (after 1 and 24h) did not cause plasma lipid peroxidation (p>0.05). We showed that in the presence of beta-glucan, lipid peroxidation in plasma samples treated with haloperidol was significantly decreased. Moreover, we did not observe the synergistic action of beta-glucan and amisulpride on the inhibition of plasma lipid peroxidation. However, the beta-d-glucan was found to be more effective antioxidant, than the solution of pure resveratrol. The presented results indicate that beta-glucan seems to have distinctly protective effects against the impairment of plasma lipid molecules induced by haloperidol.