Agriculture Reference
In-Depth Information
inevitable production of superoxide (Giorgi et al., 2012). The high respiration
caused by the phytochrome, as well as chlorophyll under strong sunlight will
reduce the accumulation of energy as carbohydrates, and finaly lead to a
reduced crop yield.
In terms of the emission of singlet oxygen via phytochrome and
chlorophyll under strong sunlight to a range of 500 µm, we should study the
results of photodynamic therapy (PDT). To kill cancer cells, in a tissue,
porphyrin derivative and PO
2
were introduced in the tissue, which was
illuminated by two laser lights of different wave-lengths to form forces in the
cancer tissues (Luksiene, 2003; Ayaru et al., 2005; Hasunuma et al., 2012).
The emission of singlet oxygen from the focus was measured by the
phosphorescence from the reaction: -Porphyrin derivative + laser lights +
triplet oxygen + PO
2
→
Porphyrin derivative exited + triplet oxygen + PO
2
→
Porphyrin derivative + singlet oxygen + PO
2
→
Porphyrin derivative +
P
2
O
5
(P
4
O
10
)+ phosphorescence (Luksiene 2003, Ayaru et al., 2005,
Hasunuma et al., 2012).
The diameter of phosphorescence was 1,000 µm, indicating that the
singlet oxygen path length was 500 µm, which is well explained by the life-
time of the singlet oxygen was within the range of 0.5 - 4 µsec.
The transfer of the energy of laser lights caused not only the excitation of
triplet oxygen to singlet oxygen but also confirmed the energy to move very
fast with no reaction with ambient materials with path length of around 500
µm. The path length of 500 µm indicated that the energy accepted by
phytochrome will cause a 500 µm range of path length for the singlet oxygen,
indicating that it will reach to neighboring cells. The finding indicates that
function of the phytocrome was to emit singlet oxygen molecules to
neighboring cells causing these to react with unsaturated fatty acids of the
plasma membrane and the vacuolar and microsomal membranes, thus
conferring these membranes to produce pores that are the actual Ca
2+
channels
in the plasma, vacuolar and microsomal membranes.
Phytochromes will function as an emitter of singlet oxygen, permitting it
to move at a range of 500 µm (Hasunuma et al., 2012), creating Ca
2+
channels
in the plasma, vacuolar and microsomal membranes, and increasing [Ca
2+
]cyt,
which will lead to the activation of mitochondrial ATP production and
inevitably, superoxide production. ATP will function to block the influx of
Ca
2+
and also function to sequester [Ca
2+
]cyt to a calcium storage sites,
vacuole and microsome (Hasunuma 1998, Giorgi et al., 2012).
