Namjoyan Foroogh, Hejazi Hoda, Ramezani Zahra
Marine Research Center, Pharmacognosy Departments, Faculty of Pharmacy, Jundishapur University of Medical Sciences, Ahvaz, IR Iran ; Faculty of Pharmacy, Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
Faculty of Pharmacy, Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
Jundishapur J Nat Pharm Prod. 2012 Fall;7(4):163-7. Epub 2012 Oct 7.
Black pepper (Piper nigrum) is one of the well-known spices extensively used worldwide especially in India, and Southeast Asia. The presence of alkaloids in the pepper, namely, piperine and its three stereoisomers, isopiperine, chavicine and isochavicine are well noticed.
The current study evaluated the effect of lyophilization and oven drying on the stability and decomposition of constituents of black pepper ethanolic extract.
In the current study ethanolic extract of black pepper obtained by maceration method was dried using two methods. The effect of freeze and oven drying on the chemical composition of the extract especially piperine and its three isomers were evaluated by HPLC analysis of the ethanolic extract before and after drying processes using diode array detector. The UV Vis spectra of the peaks at piperine retention time before and after each drying methods indicated maximum absorbance at 341.2 nm corresponding to standard piperine.
The results indicated a decrease in intensity of the chromatogram peaks at approximately all retention times after freeze drying, indicating a few percent loss of piperine and its isomers upon lyophilization. Two impurity peaks were completely removed from the extract.
In oven dried samples two of the piperine stereoisomers were completely removed from the extract and the intensity of piperine peak was increased.
黑胡椒（Piper nigrum）是一种广为人知的香料，在全球尤其是印度和东南亚被广泛使用。人们已经充分注意到胡椒中生物碱的存在，即胡椒碱及其三种立体异构体，异胡椒碱、荜澄茄碱和异荜澄茄碱。
本研究评估了冻干和烘干对黑胡椒乙醇提取物成分稳定性和分解的影响。
在本研究中，采用浸渍法获得的黑胡椒乙醇提取物用两种方法进行干燥。通过使用二极管阵列检测器对干燥前后乙醇提取物进行高效液相色谱分析，评估冷冻干燥和烘干对提取物化学成分尤其是胡椒碱及其三种异构体的影响。每种干燥方法前后胡椒碱保留时间处峰的紫外可见光谱表明，在341.2nm处有最大吸收，对应于标准胡椒碱。
结果表明，冷冻干燥后几乎所有保留时间处色谱峰的强度均降低，表明冻干后胡椒碱及其异构体损失了百分之几。提取物中的两个杂质峰被完全去除。
在烘干样品中，提取物中的两种胡椒碱立体异构体被完全去除，胡椒碱峰的强度增加。
