Som Ayub Md, Ahmat Norizan, Abdul Hamid Hairul Amani, Azizuddin NurMardhiyyah
Faculty of Chemical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia.
Accounting Research Institute (ARI), Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia.
Heliyon. 2019 Feb 18;5(2):e01244. doi: 10.1016/j.heliyon.2019.e01244. eCollection 2019 Feb.
foliage is believed to contain antioxidants similar to its peel. Numerous studies have been conducted to determine the total phenolic content (TPC) and antioxidant activity on the pulps and peels; however, similar studies on its foliage have yet to be investigated. In this study, foliage and peels were extracted using two different solvents namely; chloroform and methanol through Folin-Ciocalteu method and Diphenyl-1-Ipicrylhydrazyl (DPPH) free radical scavenging assay for TPC and antioxidant activity, respectively. As for TPC, results revealed that the peels gave higher TPC in both methanol (48.15 mg GAE/100g extract) and chloroform (18.89 mg GAE/100g extract) extractions than foliage (30.3 mg GAE/100g extract and 5.92 mg GAE/100g extract, respectively). However, when a comparison was made between foliage and peels in terms of its scavenging effects in DPPH assay, the peels contained more antioxidants (18.71%) than foliage (38.3%) in the chloroform solvent extracts. This study shows that foliage has a similar antioxidant activity as its peels and is potentially a natural antioxidant in food applications.
人们认为树叶含有与果皮类似的抗氧化剂。已经进行了大量研究来测定果肉和果皮中的总酚含量（TPC）和抗氧化活性；然而，对其树叶的类似研究尚未开展。在本研究中，分别通过福林-酚法和二苯基-1-苦基肼（DPPH）自由基清除法，使用氯仿和甲醇这两种不同溶剂对树叶和果皮进行提取，以测定TPC和抗氧化活性。至于TPC，结果显示，在甲醇（48.15毫克没食子酸当量/100克提取物）和氯仿（18.89毫克没食子酸当量/100克提取物）提取中，果皮的TPC均高于树叶（分别为30.3毫克没食子酸当量/100克提取物和5.92毫克没食子酸当量/100克提取物）。然而，在DPPH测定中比较树叶和果皮的清除效果时，氯仿溶剂提取物中果皮含有的抗氧化剂（18.71%）比树叶（38.3%）少。本研究表明，树叶具有与其果皮相似的抗氧化活性，在食品应用中可能是一种天然抗氧化剂。
