Effects of filtered liquid fertilizer and compost tea derived from livestock waste on growth of plants, antioxidants, and anti-inflammatory for Broccoli (Brassica oleracea L.)

The livestock industry plays a vital role in the economy by producing food for humans. However, the unsuitable livestock management can have detrimental effects on the environment. The methane (CH4) and nitrous oxide (N2O) produced from livestock waste led to the greenhouse effect. Thus, the livestock waste recycling is necessary to produce crops in sustainable agriculture. This study aims to assess the effects of organic liquid fertilizers derived from livestock waste on broccoli growth, antioxidants, and anti-inflammatory properties. The fertilizer treatment groups were chemical fertilizer (CF), chlorella cultured in filtered liquid fertilizer is liquid bio fertilizer (LBF), and compost tea mixed with filtered liquid fertilizer (CT+LF). The plant height, leaf length, leaf width, and SPAD values did not exhibit any significant differences in broccoli until 50 days when supplied with chemical fertilizer (CF), liquid biofertilizer (LBF), or compost tea + liquid fertilizer (CT+LF). However, the values of plant length and SPAD units on day 71 were higher in the CF group than in the LBF and CT+LF groups. Furthermore, several antioxidant activities were increased in the LBF group for DPPH or CT+LF group for nitrite scavenging, indicating that organic fertilizers can enhance antioxidant levels.