Departamento de Bioquímica, Universidade Estadual de Maringá, Maringá 87020-900, Brazil.
Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; Laboratório Associado para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; Departamento de Ciencias Farmacéuticas. Facultad de Farmacia, CIETUS-IBSAL, Universidad de Salamanca, 37007 Salamanca, España.
Food Res Int. 2023 Nov;173(Pt 1):113260. doi: 10.1016/j.foodres.2023.113260. Epub 2023 Jul 10.
Cytinus hypocistis(L.) L. is an edible parasitic plant that grows within the roots of its host. In addition to its use as famine food in the past, it is also tradidionally used for treating several illnesses such as intestinal problems, inflammations, tumors, and bleeding. This species is rich in hydrolysable tannins, compounds often associated with inhibiting starch digestion. Therefore, the present work investigated how effectively C. hypocistis tannin-rich extracts inhibited enzymes involved in starch digestion and if such effect also occurs in vivo. The latter premise was approached using the starch tolerance test in mice. Two optimized hydroethanolic extracts were used, a heat-assisted and an ultrasound-assisted extract, with known hydrolysable tannin content. Both extracts demonstrated potent inhibition of α-amylase. Inhibitions were of the mixed type with inhibitor constants in the 15 μg/mL range. The inhibition of the intestinal α-glucosidase was at least ten times less effective. The inhibition of the α-amylase was negatively affected by in vitro gastrointestinal digestion and bovine serum albumin. In vivo, both extracts inhibited starch digestion at doses between 100 and 400 mg/mL in healthy mice. The highest doses of the ultrasound and heat extracts diminished the peak glucose levels in the starch tolerance test by 46 and 59.3%, respectively. In streptozotocin diabetic mice, this inhibition occurred only at the dose of 400 mg/mL. Under this condition, diminution of the peak glucose concentration in the starch tolerance test was equal to 36.7% and 48.8% for the ultrasound and heat extracts, respectively. Maltose digestion was not inhibited by the C. hypocistis extracts. Qualitatively and quantitatively, thus, the actions of both extracts were similar. The results allow adding a new biological property to C. hypocistis, namely, the ability to decrease the hyper-glycemic excursion after a starch-rich meal, propitiating at the same time a diminished caloric intake.
蜜源木蓝是一种可食用的寄生植物，生长在其宿主的根部。除了过去作为饥荒时期的食物之外，它还被传统用于治疗多种疾病，如肠道问题、炎症、肿瘤和出血。该物种富含可水解单宁，这些化合物通常与抑制淀粉消化有关。因此，本研究旨在探讨蜜源木蓝富含单宁的提取物对参与淀粉消化的酶的抑制作用，以及这种作用是否也存在于体内。后者是通过在小鼠中进行淀粉耐量试验来研究的。使用两种优化的水醇提取物，一种是热辅助提取物，另一种是超声辅助提取物，它们具有已知的可水解单宁含量。两种提取物均能有效抑制α-淀粉酶。抑制作用属于混合类型，抑制剂常数在 15μg/mL 范围内。对肠道α-葡萄糖苷酶的抑制作用至少低 10 倍。体外胃肠消化和牛血清白蛋白对α-淀粉酶的抑制作用有负面影响。在体内，两种提取物在健康小鼠中以 100-400mg/mL 的剂量抑制淀粉消化。超声和热提取物的最高剂量分别使淀粉耐量试验中的峰值葡萄糖水平降低了 46%和 59.3%。在链脲佐菌素糖尿病小鼠中，这种抑制仅在 400mg/mL 剂量下发生。在此条件下，超声和热提取物使淀粉耐量试验中的峰值葡萄糖浓度分别降低了 36.7%和 48.8%。蜜源木蓝提取物不能抑制麦芽糖消化。因此，从定性和定量两方面来看，两种提取物的作用相似。这些结果为蜜源木蓝增加了一个新的生物学特性，即能够降低富含淀粉的膳食后的高血糖波动，同时减少热量摄入。
