anna tadevosyan

In this study, green synthesis assisted colloidal solution system was used to prepare monodispersed spherical silver nanoparticles from hydroponic Moringa oleifera Lam. leaf extract. The Moringa oleifera leaf extract used has shown great potential in the biosynthesis of silver nanoparticles for medicinal and biotechnological applications. The formation of silver nanoparticles was observed by UV-Vis spectroscopy with a surface plasmon resonance band at 425 nm after 1 hour of preparation. Transmission electron microscopy (TEM) imaging shows that the nanoparticles are spherical in shape with an average size of 20 nm. The atomic force microscopy (AFM) image showed that the Ag nanoparticles were spherical with good monodispersity, confirming the TEM results. The biomedical use of the green synthesized silver nanoparticles from medicinal plants as antimicrobial and cytotoxic agents can be suggested by their strong bioactivity and synergistic effect of Moringa oleifera and silver nanoparticles.

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.