枇杷（Eriobotrya japonica (Thunb) Lindl.）：叶水提物的营养价值、多酚组成、降血糖作用和毒性评价。

Loquat (Eriobotrya japonica (Thunb) Lindl.): Evaluation of nutritional value, polyphenol composition, antidiabetic effect, and toxicity of leaf aqueous extract.

机构信息

Biochemistry and Natural Substances Team, Department of Biology, Faculty of Sciences & Techniques, University Moulay Ismail, Errachidia, 52000, Morocco.

Biochemistry and Natural Substances Team, Department of Biology, Faculty of Sciences & Techniques, University Moulay Ismail, Errachidia, 52000, Morocco; Laboratory of Biotechnology & Sustainable Development of Natural Resources, Polydisciplinary Faculty, Beni Mellal, 23000, Morocco.

出版信息

J Ethnopharmacol. 2022 Oct 5;296:115473. doi: 10.1016/j.jep.2022.115473. Epub 2022 Jun 17.

DOI:10.1016/j.jep.2022.115473

PMID:35718052

Abstract

ETHNOPHARMACOLOGICAL RELEVANCE

Loquat (Eriobotrya japonica (Thunb.) Lindl.) is an evergreen tree native to China, which is introduced in many Mediterranean countries. As in many ancient medical systems, loquat leaves have been used in Moroccan traditional medicine to treat diabetes and its complications.

AIM OF THE STUDY

This study aims to determine the nutritional and polyphenol composition and to evaluate the in vivo antidiabetic, and antihyperlipidemic properties and oral toxicity of a leaf aqueous extract (LLE) derived from loquat grown in Morocco.

MATERIALS AND METHODS

Energy value and fiber, fatty acids, minerals, vitamins, total carbohydrate, sugar, lipid, and protein contents were determined according to international methods committee guidelines. Polyphenol profiling was carried out using the HPLC-DAD method. Mice fed a high-fat and high-glucose (HFG) diet for 10 weeks were used as a model to assess the antidiabetic and antihyperlipidemic effects of a daily administration of LLE at three different doses (150, 200, 250 mg/kg body weight (BW)/day), in comparison with metformin (50 mg/kg BW/day) and pravastatin (20 mg/kg BW/day). The oral toxicity was determined following OECD 425 Guideline.

RESULTS

Loquat leaves were found to be rich in fiber, minerals (potassium, calcium, magnesium, iron, and sodium), and vitamins (B2, B6, and B12) and lower in energy, sugar, and fat. Ten different phenolic compounds were characterized. Naringenin, procyanidin C1, epicatechin, and rutin were the more abundant compounds in LLE. The administration of the LLE dose-dependently ameliorated hyperglycemia, insulin resistance, oxidative stress, and hyperlipidemia in HFG diet-fed mice. The median lethal dose of LLE was higher than 5000 mg/kg BW.

CONCLUSIONS

Loquat leaves are a potential source of micronutrients and polyphenols with beneficial effects on diabetes and its complications.

摘要

民族药理学相关性

枇杷（Eriobotrya japonica (Thunb.) Lindl.）原产于中国，是一种常绿乔木，现已引入许多地中海国家。与许多古老的医学体系一样，枇杷叶在摩洛哥传统医学中被用于治疗糖尿病及其并发症。

研究目的

本研究旨在确定其营养成分和多酚组成，并评估源自摩洛哥种植的枇杷叶的水提物（LLE）的体内抗糖尿病和抗高血脂特性及口服毒性。

材料和方法

根据国际方法委员会指南，测定能量值和纤维、脂肪酸、矿物质、维生素、总碳水化合物、糖、脂质和蛋白质含量。采用 HPLC-DAD 法进行多酚分析。用高脂肪高葡萄糖（HFG）饮食喂养 10 周的小鼠作为模型，评估 LLE 以三种不同剂量（150、200、250mg/kg 体重（BW）/天）、与二甲双胍（50mg/kg BW/天）和普伐他汀（20mg/kg BW/天）的抗糖尿病和抗高血脂作用。根据 OECD 425 指南确定口服毒性。

结果

枇杷叶富含纤维、矿物质（钾、钙、镁、铁和钠）和维生素（B2、B6 和 B12），而能量、糖和脂肪含量较低。鉴定出 10 种不同的酚类化合物。橙皮素、原花青素 C1、表儿茶素和芦丁是 LLE 中更丰富的化合物。LLE 剂量依赖性地改善了 HFG 饮食喂养小鼠的高血糖、胰岛素抵抗、氧化应激和高血脂。LLE 的半数致死量大于 5000mg/kg BW。