Kgosana Kedibone G, Matlala Tirelo
Department of Pharmacology and Therapeutics, Faculty of Medicine, Sefako Makgatho Health Sciences University, Pretoria.
Onderstepoort J Vet Res. 2024 Dec 13;91(1):e1-e10. doi: 10.4102/ojvr.v91i1.2182.
Plant foliages used as feed additives pose a health risk due to high oxidant concentrations. Oxidants cause oxidative stress and high rate of morbidities and mortalities. Hence, the aim of the study was to validate the methods to quantify gallic acid (GA) and quercetin (Q) as putative antioxidants, and to evaluate antioxidant activities in feed (F), Hyperacanthus amoenus (HA) and Carissa bispinosa (CB) extracts. Extraction was carried out with 62.5% methanol. Method validations for linearity, accuracy and precision were performed on high performance liquid chromatography. Quantitative analysis of GA and Q and testing of 2,2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activities in the extracts were performed. The lowest limit of detection (LOD) and limit of quantitation (LOQ) of 0.011 µg/mL and 0.032 µg/mL were determined in HA, respectively. The methods were accurate and precise as the relative standard deviations (%RSD) were less than 15%. The GA concentrations in CB and HA extracts were statistically significant (p 0.05) and their values were 0.65 ± 0.03 x 106 µg/kg dry weight (DW) (0.13%) and 0.28 ± 0.06 x 106 µg/kg DW (0.002%), respectively. All extracts showed very strong radical scavenging activities with their IC50 values ranging between 5.87 µg/mL and 6.86 µg/mL.Contribution: These accurate, repeatable, precise and reliable methods can be used to provide a valuable basis for GA and Q analysis in various shrub foliages. Though high GA concentrations have potential to act as antioxidants, they may have adverse health and growth performance effects when used as feed additives, while lower Q concentrations may have no effects on livestock.
用作饲料添加剂的植物叶子因氧化剂浓度高而构成健康风险。氧化剂会导致氧化应激以及高发病率和死亡率。因此，本研究的目的是验证定量测定没食子酸（GA）和槲皮素（Q）作为假定抗氧化剂的方法，并评估饲料（F）、美丽长刺树（HA）和双刺假虎刺（CB）提取物中的抗氧化活性。用62.5%的甲醇进行提取。对高效液相色谱法进行了线性、准确度和精密度的方法验证。对提取物中的GA和Q进行了定量分析，并测试了2,2-二苯基-1-苦基肼（DPPH）清除活性。在HA中分别测定出最低检测限（LOD）和定量限（LOQ）为0.011µg/mL和0.032µg/mL。由于相对标准偏差（%RSD）小于15%，这些方法准确且精密。CB和HA提取物中的GA浓度具有统计学意义（p<0.05），其值分别为0.65±0.03×106µg/kg干重（DW）（0.13%）和0.28±0.06×106µg/kg DW（0.002%）。所有提取物均表现出非常强的自由基清除活性，其半数抑制浓度（IC50）值在5.87µg/mL至6.86µg/mL之间。贡献：这些准确、可重复、精密且可靠的方法可用于为各种灌木叶子中的GA和Q分析提供有价值的基础。尽管高浓度的GA有作为抗氧化剂的潜力，但当用作饲料添加剂时，它们可能对健康和生长性能产生不利影响，而较低浓度的Q可能对牲畜没有影响。
