Chiawa Sylvia C, Attaugwu Roseline N, Uvere Peter O
Department of Food Science and Technology, University of Nigeria, Nsukka, Nigeria.
Department of Food Science and Technology, Madonna University, Enugu, Nigeria.
J Sci Food Agric. 2023 Mar 15;103(4):2070-2076. doi: 10.1002/jsfa.12323. Epub 2022 Nov 21.
Soaking and air-resting are processing steps in malting. This has been reported to increase metabolic and enzyme activities in rice paddy as a result of exposure of the grain to atmospheric oxygen. The present study evaluated the effect of soaking and air-resting on the phytochemical composition of Piper guineense seeds. The seed extracts were prepared by: soaking the seeds in water for 4 h; air-resting for 30, 60, 90, and 120 min; and re-soaking for another 4 h. The out-of-steep seeds were milled and an extract was formed by tissue homogenization and maceration using ethanol. The phytochemical, antioxidant, and antibacterial properties of the seed extract were determined using standard methods.
The alkaloid, flavonoid, saponin, tannin, and total phenol contents were 0.126-0.268, 0.091-0.172, 0.080-0.123, 0.00-0.107, and 0.447-0.908 g kg respectively. The antioxidant properties (reducing power) of the seed extracts were concentration-dependent and were in the range 1.08-3.24 g kg at 8 mg mL , 1.14-3.47 g kg at 16 mg mL , 1.30-3.35 g kg at 24 mg mL , 1.26-3.11 g kg at 32 mg mL , and 1.13-3.04 g kg at 40 mg mL , respectively. The antibacterial activities against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa showed that, at 100 mg mL , the inhibition zone diameters of the seed extracts were in the range 10-23 mm.
Soaking and air-resting of P. guineense seeds increased the phytochemical components of the seeds. The extracts from the seeds air-rested for 30 min showed the highest phytochemical contents and had the highest antioxidant and antimicrobial properties. © 2022 Society of Chemical Industry.
浸泡和空气静置是麦芽制造中的加工步骤。据报道，由于谷物暴露于大气氧气中，这会增加稻谷中的代谢和酶活性。本研究评估了浸泡和空气静置对几内亚胡椒种子植物化学成分的影响。种子提取物的制备方法如下：将种子在水中浸泡4小时；空气静置30、60、90和120分钟；然后再浸泡4小时。将沥干的种子研磨，通过组织匀浆和用乙醇浸渍形成提取物。使用标准方法测定种子提取物的植物化学成分、抗氧化和抗菌特性。
生物碱、黄酮类化合物、皂苷、单宁和总酚含量分别为0.126 - 0.268、0.091 - 0.172、0.080 - 0.123、0.00 - 0.107和0.447 - 0.908 g/kg。种子提取物的抗氧化特性（还原能力）呈浓度依赖性，在8 mg/mL时为1.08 - 3.24 g/kg，16 mg/mL时为1.14 - 3.47 g/kg，24 mg/mL时为1.30 - 3.35 g/kg，32 mg/mL时为1.26 - 3.11 g/kg，40 mg/mL时为1.13 - 3.04 g/kg。对大肠杆菌、金黄色葡萄球菌和铜绿假单胞菌的抗菌活性表明，在100 mg/mL时，种子提取物的抑菌圈直径在10 - 23 mm范围内。
几内亚胡椒种子的浸泡和空气静置增加了种子的植物化学成分。空气静置30分钟的种子提取物显示出最高的植物化学成分含量，并具有最高的抗氧化和抗菌性能。© 2022化学工业协会。
