PDF(Pubmed)
Abstract：
Sour orange (Citrus aurantium) seeds are typically discarded by juice processors as waste. This study aimed to extract protein isolates, produce hydrolysates from de-oiled sour orange seeds (SOS), and characterize their physicochemical properties. Previous studies have described methods to obtain protein isolates and hydrolysates from agricultural residues. However, there is limited data on the SOS. This research characterized protein isolates and hydrolysates from SOS, emphasizing yield, purity, and amino acid composition. Protein isolates were extracted using borate saline buffer, saline, and distilled water. Enzymatically hydrolysis was conducted using Protamex® (a commercial protease) at concentrations ranging from 0.2 to 5 g enzyme/100g protein isolate. Differential scanning calorimetry, electrophoresis, and FT-IR spectroscopy were utilized to characterize the isolates and hydrolysates. Data showed that using 5 % saline resulted in protein extraction with a yield and purity of 30 and 86 %, respectively. DSC analysis revealed that the denaturation temperature of the protein isolate was 68 °C, while the hydrolysates exhibited structural instability, as indicated by a decrease in enthalpy change compared to the isolate. The protein isolate had a 76° contact angle. The amino acid profile showed a significant presence of glutamic acid (130.530 mg/g) and arginine (70.210 mg/g). Electrophoresis analysis exhibited four major bands of the protein. The bands\' intensity decreased, and new bands appeared after hydrolysis. The enzyme hydrolysis was confirmed using the O-phthaldialdehyde method and FTIR. Findings revealed that based on the free amine group quantity, the hydrolysate obtained using 5 g enzyme/100g protein isolate was 14.220 ± 0.299 μmol/mg protein. The study concluded that sour orange seeds are a good source of protein, with protein isolates and hydrolysates exhibiting desirable characteristics. More research needs to be conducted to acquire further information about their functional properties and potential applications.
摘要：
酸橙（柑橘）种子通常被果汁加工者作为废物丢弃。本研究旨在提取分离蛋白,从脱油酸橙种子（SOS）生产水解产物，并表征其物理化学性质。先前的研究已经描述了从农业残留物获得蛋白质分离物和水解产物的方法。然而,SOS上的数据有限。这项研究表征了来自SOS的分离蛋白和水解产物，强调产量，纯度,和氨基酸组成。使用硼酸盐盐水缓冲液提取蛋白质分离物，盐水,和蒸馏水。使用Protamex®(商业蛋白酶)以0.2至5g酶/100g蛋白分离物的浓度进行酶水解。差示扫描量热法,电泳,和FT-IR光谱用于表征分离物和水解产物。数据显示，使用5％盐水导致蛋白质提取的产率和纯度为30％和86％，分别。DSC分析表明，分离蛋白的变性温度为68°C，虽然水解产物表现出结构不稳定性，与分离物相比，焓变化降低。蛋白质分离物具有76°的接触角。氨基酸谱显示谷氨酸(130.530mg/g)和精氨酸(70.210mg/g)的显著存在。电泳分析显示蛋白质的四个主要条带。带强度下降，水解后出现新的条带。使用邻苯二甲醛方法和FTIR确认酶水解。研究结果表明，根据游离胺基的数量，使用5g酶/100g蛋白分离物获得的水解产物为14.220±0.299μmol/mg蛋白。该研究得出结论，酸橙种子是蛋白质的良好来源，与蛋白质分离物和水解产物表现出理想的特性。需要进行更多的研究，以获取有关其功能特性和潜在应用的进一步信息。
