The production of rubber in 2016 is 26.9
million tonnes in the world. It separated 46% of world rubber manufacture and production
54% of artificial rubber. The rubber usage is more than 27 million tonnes. It
is increase than 2015 (1.8%) (MREPC, 2017). Rubber is known as latex.
Latex is gotten from rubber tree and
had been used for since long ago. Latex has many special things that make it most
vital polymers that having a lot of proteins,
organelles, mainly rubber particles, and
particles (d’Auzac and Jacob, 1989). The hydrophobic fundamental
of polyisoprene bordered by a lipo-protein complex layer called rubber particle (Wren, 1941; Nawamawat
et al., 2011) and the particle membrane was exposed as a watery monolayer (Wood
and Coornish, 2000; Siler et al., 1997; Nawamawat et al., 2011; Coornish et al.
1999). The particle membrane was predictable nearby 1.5–3.0 nm (Wren,
1941; Siler et al., 1997; Nawamawat et al., 2011). Rubber particles contain lipids
is 1.6–3.7% that classified as neutral lipids, glycolipids and phospholipids (Liengprayoon,
2008; Hasma and Subramaniam, 1986; Ho et al., 1976). Rhodes and Bishop (1930) identified
the phospholipids at present, the mainly phosphatidyl choline (PC) and
ethanolamine (PE), and the latex are contain phosphatidyl inositol (PI), serine
(PS), glycerol (PG) and phosphatidic acid (PA) (Siler et al., 2008;
Liengprayoon, 2008; Hasma, 1991).
related the linear polyisoprene chains ?-terminal phosphate group, even though
the ?-terminal (the trans initiator group) might work together with
proteins (Carretero-Gonzalez et al., 2010; Tarachiwin et al., 2005a; Tarachiwin
et al., 2005b). The harmful responsibilities of the lipid polar head groups might
cross-link in ionic linkages, for example magnesium ion with the polymeric
chains phosphate or diphosphate terminal.
proteins also contribute of the negative responsibility of the particle
surface. The further proteins want to explore besides the well-known rubber
particle-bound of rubber elongation factor (REF) and small rubber particle
protein (SRPP), it to clarify the regulatory and molecular rubber biosynthesis mechanisms.
Lately, Dai et al (2013) were identified 186 rubber particle proteins. Siler et
al. (1997) says that the expressively hang on the enzymes and protein factors located
on the rubber particles membranes from the rubber yield (the rate of
biosynthesis) and rubber quality (the supply of molecular mass, Mr). The major efforts are being complete to
isolate the key enzymes or proteins related to rubber biosynthesis in various
rubber plants like Hevea brasiliensis,
Parthenium argentatum, Ficus elastica and Taraxacum koksaghyz (Kang et al.
2000; Duan et al. 2006; Schmidt et al. 2010; Wahler et al. 2012).
Gronover et al. (2011) say that the assimilated proteins or
protein complexes catalyzed rubber biosynthesis at the superficial of rubber
mevalonate (MVA) pathway is the conventionally isoprenoid biosynthesis pathway meanwhile
in 1950s. The rubber formation was derived from a
high level of incorporation of radiolabelled pathway intermediates such as
mevalonate (Skilleter and Kekwick, 1971) and 3-hydroxy-3-methylglutaryl
coenzyme A (HMG CoA) (Hepper and Audley, 1969) into rubber to backing the
cytosolic pathway. Only in more years that are recent,
the plastidic 1-deoxy-D-xylulose 5-phosphate/2-C-methyl-D-erythritol
4-phosphate (MEP) pathway has been considering a possible alternative route for
rubber biosynthesis. This pathway has been well characterizing, not only in bacterial
but also in plant species (Lichtenthaler, 1999; Rodriguez-Concepcion and
Boronat, 2002). The expression of 1-deoxy-D-xylulose 5-phosphate synthase
(DXPS) in Hevea latex and leaves
suggests that the MEP pathway exists in the laticifer (Ko et al., 2003) and
therefore could provide an alternative means of generating IDP for
cis-polyisoprene synthesis. IDP was produced Hevea cis-polyisoprene from biosynthesis pathway of plant
isoprenoid (Kekwick, 1989).
Rubber transferase (EC 18.104.22.168) is a membrane-bound cis-prenyltransferase
(CPT). It is an enzyme that catalyzing the rubber molecule elongation (Cornish
and Xie, 2012) that makes a sequential condensation of isopentenyl
pyrophosphate with prenyl groups. Arabidopsis
thaliana is the first identified as CPT plant (Oh et al., 2000). Asawatreratanakul
et al. (2003) known two CPTs expressed in laticifers, were cloned in H. brasiliensis, and Schmidt et al. (2010b)
find the three CPTs were identified and isolated in T. koksaghyz. The enzyme that rubber particles active, were isolated
from all cytoplasmic components. It used in biochemical investigation as an
alternative of purified enzymes since an active rubber transferase. During active
rubber transferase, the enzyme has not yet been purified and its enzymatic
nature remains elusive (Cornish and Xie, 2012). The rubber biosynthesis can produce
the different class of the natural rubber.
2500 species of plants produced natural rubber (van Beilen and
Poirier, 2007; Metcalfe, 1967). Even thought, H. brasiliensis, P. argentatum
(guayule), and T. koksaghyz known as pledge
rubber crops (van Beilen and Poirier, 2007). Not
only theirs, the natural rubber has also been identified in Ficus species (F. benghalesis, F. elastica and F. carica) (Kang et al., 2000a; Cornish,
2001a), Euphorbia species (E.
etherophylla, and E. lactiflua)
and Artocarpus heterophyllus
(Mekkriengkrai et al., 2004), and Alstonia
scholaris, the key source of this material.
A. scholaris (family: Apoceae) is a high perennial tree commonly distributed in
China, India, Southeast Asia, and Australia that create tart white latex. This
tree is a medicinal plant that produces a large amount of latex. The present
study or A. scholaris shows the pharmacognostic and phytochemical
properties of various bioactive compounds. Some of the meticulous studies on
this plant have proved its medical value beyond any doubt as mentioned
motivating for exploring more information about this plant. Alstonia is
known to be rich sources of monoterpenoid indole alkaloids with diverse
structures and significant bioactivities, some of which have attracted
attention as new drug leads as well as challenging targets for total synthesis.
The latex is easily collect from the green part of tree example young leaves
The latex of A. scholaris known has several functions such as
pharmacology. It can be used for remedy for toothache and neuralgia and treat
the ulcer. Althought, The information of A.
scholaris latex proteins are so limited. The latex proteins there for the
investigation and identification of its proteins in rubber particles and their
transferase activity need to observe. This study works on purification of A. scholaris rubber protein latex and
identified the micromorphology of lipid and rubber
particle from its latex of their size.