夏枯草种子与奇亚籽、兰香子的性状、膨胀度和化学组成比较

Comparison of Character,Turgidity and Chemical Composition of Prunellae Spica Seeds,Chia Seeds and Basil Seeds

目的:为了充分挖掘夏枯草药用部位果穗在采收加工、储存和运输过程中脱落的夏枯草种子的利用价值,对其进行性状、膨胀度和化学组成研究,并与市售的奇亚籽和兰香子进行比较。方法:性状采用直接观察法;膨胀度按照2020年版《中华人民共和国药典》(四部)通则2101方法测定;采用超高效液相色谱法(UPLC)测定其中6种酚酸类成分(丹参素、原儿茶酸、原儿茶醛、咖啡酸、异迷迭香酸苷和迷迭香酸)的含量,流动相乙腈(A)-0.1%甲酸水溶液(B)梯度洗脱(0~7 min,2%~8%A;7~13 min,8%A;13~14 min,8%~17%A;14~30 min,17%A),检测波长280 nm;采用正己烷提取脂溶性成分,利用气相色谱-质谱法(GC-MS)鉴定其中的脂肪酸,并对5种含量较高的棕榈酸、油酸、硬脂酸、亚油酸和α-亚麻酸进行含量测定,DB-35MS毛细管柱(0.25 mm×60 m,0.25μm),进样温度250℃,载气为高纯氦气,流速1.0 mL·min^(-1),分流比50∶1;采用水蒸气蒸馏法提取挥发油,GC-MS鉴定其挥发性成分组成,WM-5MS毛细管柱(0.25 mm×30 m,0.25μm),进样温度250℃,流速1.0 mL·min^(-1),分流比10∶1。结果:夏枯草种子较奇亚籽、兰香子略小,三者种皮颜色明显不同;夏枯草种子具有较强的吸水膨胀特性,膨胀度17.4 mL·g^(-1),低于奇亚籽的25.2 mL·g^(-1)和兰香子的35.6 mL·g^(-1)。夏枯草种子含有丰富的酚酸和脂肪酸,挥发油含量极低,其中酚酸类成分以异迷迭香酸苷和迷迭香酸为主,二者质量分数分别为0.579%和0.392%;正己烷提取物中5种脂肪酸总量90.1%,总不饱和脂肪酸质量分数80.6%,其中α-亚麻酸质量分数50.0%,略低于奇亚籽的57.2%,与兰香子的50.0%相当。结论:夏枯草种子吸水膨胀性好,酚酸和不饱和脂肪酸含量丰富,特别是具有高含量的α-亚麻酸,可对其进行功能食品开发,从而实现夏枯草废弃资源的综合利用。

Objective:In order to explore the utilization value of the seeds dropped in the harvesting,processing,storage and transportation of Prunellae Spica,the character,turgidity and chemical composition of the seeds were analyzed and compared with those of the commercially available varieties,such as chia seeds and basil seeds.Method:Character was observed directly.The turgidity was determined according to the method of general rule 2101 of Chinese Pharmacopoeia(partⅣ,the 2020 edition).The contents of six phenolic acids(danshensu,protocatechuic acid,protocatechuic aldehyde,caffeic acid,salviaflaside and rosmarinic acid)were determined by ultra performance liquid chromatography(UPLC),acetonitrile(A)-0.1% formic acid aqueous solution(B)was used as mobile phase for gradient elution(0-7 min,2%-8%A;7-13 min,8%A;13-14 min,8%-17%A;14-30 min,17%A),the detection wavelength was at 280 nm.The liposoluble components were extracted by n-hexane and identified by gas chromatography-mass spectrometry(GC-MS),and the contents of five fatty acids,namely palmitic acid,oleic acid,stearic acid,linolic acid andα-linolenic acid,were determined on a DB-35MS capillary column(0.25 mm×60.0 m,0.25μm),the injection temperature was 250℃,the carrier gas was high-purity helium with a flow rate of 1.0 mL·min^(-1)and the splitting ratio of 50∶1.The volatile oil was extracted by steam distillation method and its components were identified by GC-MS on a WM-5MS capillary column(0.25 mm×30.0 m,0.25μm)with the injection temperature of 250℃,the flow rate of 1.0 mL·min^(-1)and the splitting ratio of 10∶1.Result:Prunellae Spica seeds were slightly smaller than chia seeds and basil seeds,and their color of seed coat was obviously different.Prunellae Spica seeds had strong water absorption and swelling characteristics,and the turgidity was 17.4 mL·g^(-1),which was lower than that of chia seeds(25.2 mL·g^(-1))and basil seeds(35.6 mL·g^(-1)).Prunellae Spica seeds were rich in phenolic and fatty acids,while the content of volatile oil was very low.The main phenolic acids were salviaflaside and rosmarinic acid,with the contents of 0.579% and 0.392%,respectively.The total content of five fatty acids in n-hexane extract was 90.1%,and total content of unsaturated fatty acids was 80.6%,among which content of α-linolenic acid was 50.0%,which was slightly lower than 57.2% of chia seeds and similar to 50.0% of basil seeds.Conclusion:Prunellae Spica seeds have good turgidity,rich in phenolic acids and unsaturated fatty acids,and especially with high amount of α-linolenic acid.It is worthy of being developed as functional food to realize comprehensive utilization of the waste resources of Prunellae Spica.