To the best of our knowledge, we demonstrated for the first time
that air and oxygen-nanobubbles promote the growth of plants,
fishes, and mice. Yoshida et al. demonstrated that cucumber
plants at higher dissolved oxygen concentration showed increased
area and weight of leaves [13]. In addition, Park et al demonstrated
that air-microbubbles promote the growth of leaf lettuce
compared to air-macrobubbles, in which report DO of cultured
water at the beginning was very similar to that of us (about
8.5 mg/L) [15]. On the other hand, DO in cultured water on day
14 was relatively higher in our study (air-nanobubble water; about
9.2 mg/L) as compared to Park’s report (air-microbubble water;
about 8.2 mg/L). This difference is in accordance with the
previous report which speculated nannobubbles increase the
oxygen partial pressure (PO2) values in water to greater extent
than that of microbubbles [1,2]. In our study, nutrient solution
except for oxygen did not differ between two groups (data not
shown), but Park et al also speculated that larger specific surface
area of the microbubbles as well as negative electronic charges on
their surface may promote the growth of plants because
Figure 5. Sequential changes of dissolved oxygen concentration (DO) and pH of cultured water. DO (A) and pH (B) of Brassica campestris
cultured water were monitored sequentially. Data are shown as mean 6 S.D. (n = 5 in each group). ***P,0.001.
doi:10.1371/journal.pone.0065339.g005
Nanobubble Water Promotes the Growth of Lives
PLOS ONE