Counts of healthy GFP+ cells decreased over time (Fig. 3a). The
greatest mean rate of decrease in the number of healthy cells was
observed during the first one and a half hours for all samples, suggesting
that the initial shock of entering OJ caused the largest effect on pHi and
physiology; this decrease is mirrored by increases in numbers of injured
and dead (PI+) bacteria (Fig. 3b–c). Therewere significant differences between
the number of healthy bacteria in 0.7 μm-filtered OJ and to other
samples incubated for 3, 4.5 and 6 h, and between the 0.7 μm-filtered OJ
and 0.22 μm- and 1.2 μm-filtered OJ at 24 h (Fig. 3a). This points to a
role for components in the OJ cloud between 0.7 μm and 0.22 μm in size
being damaging to bacteria; this is likely to comprise hesperidin crystals.
Presence of cloud particles larger than 0.7 μm appears to protect bacteria
against these harmful effects.