Recombinant human insulin has been successfully
expressed and produced in oilseeds of plant Arabidopsis
thaliana [27]. This technology involved the targeted expression
of insulin in subcellular organelles known as
oilbodies that allowed very high level of expression with
easy recovery of recombinant insulin. Oilbodies are
storage organelles inside the oilseeds, which comprises
of hydrophobic triacylglycerol core encapsulated by
phospholipid membrane and an outer wall of proteins
known as oleosins. Genetically engineered oil seeds have
been generated with recombinant protein specifically
targeted to oilbodies as oleosin fusion [27,82,83]. Then
the oilbodies are easily separated from other seed components
by liquid-liquid phase separation, which reduced
the number of chromatography steps required to
obtain purified insulin. It has been observed that insulin
accumulated to high level in transgenic seed (0.13% of
total seed protein). Recombinant insulin was cleaved