MICROBIOLOGICAL, IMMUNOLOGICAL, AND PHYSIOLOGICAL EFFECTS OF LONGEVITY SPINACH (GYNURA PROCUMBENS): IN-VITRO AND IN-VIVO

    

Longevity spinach, Gynura procumbens, has been traditionally used to treat a variety of diseases such as eruptive fevers, rash, kidney disease, migraines, constipation, hypertension, diabetes, and cancer. Recently, several papers have reported that this plant also has anti–Herpes simplex virus, anti–hyperglycemic, anti–hyperlipidemic, anti–inflammatory, analgesic, and reduced blood hypertension properties. However, to the best of our knowledge, nothing has been done to modulate stress in aquatic animals using G. procumbens. Therefore, we have investigated the potential of Gynura to modulate stress and immune responses in fish, tilapia. 

I examined the effects of Gynura by well and disc-diffusion methods against nine selected bacteria. In the well diffusion method, Gynura in ethanol extract showed significant sensitivity against E. feacalis (p<0.05) and P. aeruginosa (p<0.05) with the presence of zone of inhibition. In the disc diffusion method, Gynura in ethanol extract showed significant sensitivity against B. subtilis (p<0.05), S. aureus (p<0.05), and S. epidermidis (p<0.05). Similarly, Gynura in methanol extract also showed significant sensitivity against B. subtilis (p<0.05) and S. aureus (p<0.05). 

I used different concentrations of ethanol and aqueous extracts of Gynura to investigate its effects on the inhibition of B16 murine melanoma cells and proliferation of spleen cells collected from BALB/c mice. In these experiments, 4g/mL and 0.8g/mL of ethanolic extract significantly inhibited the melanoma cell growth in-vitro (p<0.05). However, there was neither significant proliferation nor inhibition of spleen cells ethanol or aqueous extracts of Gynura with different concentration (p<0.05). 

I used Gynura-supplemented feed to prevent stress and to treat stressed fish for both short and long propagation periods. In these experiments, Gynura significantly prevented the stress hormone, cortisol, from increasing in the prevention group (p<0.05) and significantly reduced cortisol in the treatment group (p<0.05). The blood glucose level was decreased in prevention and treatment group compared to control. Because of their correlated effects, improvement of overall immunity was observed in the immunological responses, especially in serum lysozyme activity (p<0.05). 

Gynura procumbens has the potential to be used as the nutraceuticals to modulate stress and immune responses in vertebrates.