Department of Nutrition and Dietetics, Harokopio University, 70 El. Venizelou Str., Kallithea 176 76, Greece.
Institute of Chemical Biology, National Hellenic Research Foundation, 48 Vas. Constantinou Ave., Athens 116 35, Greece.
Food Funct. 2021 Apr 26;12(8):3366-3380. doi: 10.1039/d1fo00122a.
Beta-glucans are polysaccharides that exhibit a wide range of biological properties as a result of their varying chemical composition. Like all dietary fibers, they avoid catabolism in the upper gastrointestinal tract, and they reach the large intestine undigested. There, they undergo fermentation by the gut microbiota, a process that has potential beneficial effects for the host. The aim of this systematic review is to assess the effects of consumption of beta-(1 → 3,1 → 6)-d-glucans, naturally found in the cell walls of fungi, on health outcomes.
A comprehensive literature search was performed on PubMed, Cochrane Library and Web of Science to retrieve studies that applied randomized controlled trials (RCTs) to investigate the impact of exclusive oral administration of fungal beta-glucans in any form and at any dosage to healthy subjects or patients.
Thirty-four RCTs, of the 917 records retrieved in total, met the eligibility criteria and are included in the present review. The sources of fungal beta-glucans were Saccharomyces cerevisiae, Aureobasidium pullulans, Pleurotus ostreatus, Lentinula edodes and Ganoderma lucidum, and the dosage of supplementation ranged from 2.5 to 1000 mg daily for up to 6.5 months. The primary physiological outcome of the majority of the interventions was immunomodulation, which resulted in (a) strengthened immune defense that reduces the incidence and symptoms of cold, flu and other respiratory infections and (b) improvement of allergic symptoms. However, the findings on the induction of immune response alterations were inconsistent at the cellular and molecular levels. Another aspect is psychological wellbeing, as the cohorts that received the polysaccharides of interest reported improvement in their mood states as well as amelioration of overall wellbeing. At the same time, it might also be useful as a complementary agent to patients undergoing cancer therapies. Furthermore, supplements containing beta-(1 → 3,1 → 6)-d-glucan administered to overweight/obese adults might have the potential to decrease comorbid conditions associated with obesity. Notably, no adverse event causally related to glucans was recorded.
Supplementation with beta-(1 → 3,1 → 6)-d-glucans is well-tolerated, and health-promoting properties are manifested primarily through the potentiation of the immune system. More studies are required to confirm their additional beneficial effects, to establish the optimal dose, and to reveal the underlying molecular mechanisms.
β-葡聚糖是一种多糖，由于其化学组成的不同，表现出广泛的生物学特性。与所有膳食纤维一样，它们在上消化道避免被分解代谢，并且未被消化而到达大肠。在那里，它们被肠道微生物群发酵，这个过程对宿主可能有潜在的有益影响。本系统评价的目的是评估天然存在于真菌细胞壁中的β-（1→3,1→6）-d-葡聚糖的消耗对健康结果的影响。
在 PubMed、Cochrane 图书馆和 Web of Science 上进行了全面的文献检索，以检索应用随机对照试验（RCT）来研究以任何形式和任何剂量单独口服真菌β-葡聚糖对健康受试者或患者的影响的研究。
从总共检索到的 917 条记录中，有 34 项 RCT 符合入选标准并包含在本综述中。真菌β-葡聚糖的来源为酿酒酵母、出芽短梗霉、糙皮侧耳、香菇和灵芝，补充剂量范围为每天 2.5 至 1000mg，持续 6.5 个月。大多数干预措施的主要生理结果是免疫调节，这导致（a）增强免疫防御，减少感冒、流感和其他呼吸道感染的发病率和症状，以及（b）改善过敏症状。然而，在细胞和分子水平上，诱导免疫反应改变的结果并不一致。另一方面是心理健康，因为接受感兴趣多糖的队列报告说他们的情绪状态有所改善，整体幸福感也有所改善。同时，它也可能对接受癌症治疗的患者有用。此外，给予超重/肥胖成年人含有β-（1→3,1→6）-d-葡聚糖的补充剂可能具有降低与肥胖相关的合并症的潜力。值得注意的是，没有记录到与葡聚糖有关的不良事件。
β-（1→3,1→6）-d-葡聚糖的补充是耐受良好的，并且通过增强免疫系统表现出主要的促进健康特性。需要更多的研究来确认其额外的有益效果，确定最佳剂量，并揭示潜在的分子机制。
