Comparison of Growth, Antioxidant, and Antibacterial Activities in Hydroponic and Soil-grown Moringa oleifera in Armenia

Moringa oleifera Lam. is a well-known medicinal plant and food source. It is rich in bioactive substances, has several pharmacological properties, and is an introduced species to Armenia. This study aimed to evaluate moringa for its adaptability to Armenian climatic conditions while assessing its antioxidant and antibacterial activities in different cultivation systems. Moringa plants were grown in soil and hydroponic systems (on special substrates: volcanic slag, gravel, volcanic slag mixed with gravel). Growth characteristics, yield, antioxidant activity, and antibacterial properties were investigated. The results showed that moringa can easily adapt to the Armenian climate. It is important to note that leaf dry mass increased by 1.6-1.7-fold in hydroponic-grown plants compared to soil-grown plants, regardless of the growth substrate. A greater antioxidant activity was observed in plants that grew on gravel only and gravel mixed with volcanic slag substrates. A comparative study of the antibacterial activity of moringa leaf water extract revealed that an extract of 5000 µg mL-1 from plants in hydroponic conditions suppressed the growth of gram-positive (Enterococcus hirae) and gram-negative (Escherichia coli) bacteria in 24 hours. Soil-grown plants had similar extracts by concentration that inhibited the growth of gram-negative bacteria. Thus, moringa plants adapted easily to the Armenian climate. The plants performed better in the hydroponic system than the soil system. This superiority in performance appeared in plant growth, yield, antioxidant activity, and antibacterial properties.