Department of Pharmacology, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand.
Department of Food Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand.
Molecules. 2023 Sep 23;28(19):6775. doi: 10.3390/molecules28196775.
Salak seed extract () is known for its high antioxidant content and low caffeine levels, making it a promising candidate for the development of value-added health products. However, there is a lack of scientific evidence for its anti-hyperglycemic effects. To address this, we investigated the in vitro and in vivo anti-hyperglycemic and antioxidant effects of salak seed extract. The HPLC chromatogram of salak seed extract shows a prominent peak that corresponds to chlorogenic acid. In vitro studies revealed that salak seeds inhibited α-glucosidase activity and glucose uptake in Caco-2 cells in a concentration-dependent manner, while also exhibiting antioxidant properties. The extract exhibits a non-competitive inhibition on α-glucosidase activity, with an IC and K of 16.28 ± 7.22 and 24.81 μg/mL, respectively. In vivo studies utilizing streptozotocin-nicotinamide-induced diabetic mice showed that the extract significantly reduced fasting blood glucose (FBG) levels in the oral glucose tolerance test. Continuous administration of the salak seed extract resulted in lower FBG levels by 13.8% as compared with untreated diabetic mice, although this change was not statistically significant. The estimated LD value of salak seed extract exceeds 2000 mg/kg, and no toxicity symptoms have been detected. Our research supports that salak seed extract has the potential to serve as a functional food or supplement that may be beneficial in reducing postprandial hyperglycemia among people with type 2 diabetes. This effect was explained by the salak's inhibitory mechanisms of glucose absorption due to inhibition of both α-glucosidase activity and intestinal glucose uptake, coupled with its antioxidant effects.
龙宫果提取物 () 因其高抗氧化含量和低咖啡因水平而闻名，使其成为开发增值保健品的有前途的候选物。然而，其抗高血糖作用的科学证据不足。为了解决这个问题，我们研究了龙宫果提取物的体外和体内抗高血糖和抗氧化作用。龙宫果提取物的 HPLC 色谱图显示出一个显著的峰，对应于绿原酸。体外研究表明，龙宫果抑制 α-葡萄糖苷酶活性和 Caco-2 细胞中的葡萄糖摄取呈浓度依赖性，同时表现出抗氧化特性。该提取物对 α-葡萄糖苷酶活性表现出非竞争性抑制作用，IC 和 K 分别为 16.28 ± 7.22 和 24.81 μg/mL。利用链脲佐菌素-烟酰胺诱导的糖尿病小鼠进行的体内研究表明，该提取物在口服葡萄糖耐量试验中显著降低了空腹血糖 (FBG) 水平。与未治疗的糖尿病小鼠相比，连续给予龙宫果提取物可使 FBG 水平降低 13.8%，尽管这一变化无统计学意义。龙宫果提取物的估计 LD 值超过 2000 mg/kg，且未检测到毒性症状。我们的研究支持龙宫果提取物具有作为功能性食品或补充剂的潜力，可能有益于降低 2 型糖尿病患者的餐后高血糖。这种作用是通过龙宫果抑制葡萄糖吸收的机制来解释的，因为它既抑制了 α-葡萄糖苷酶活性，又抑制了肠道葡萄糖摄取，同时还具有抗氧化作用。
