Ber and other Jujubes monograph.pdf - Crops for the Future

2.3.4.2 Glycosides/saponins
The glycoside saponin is found in the seeds, leaf and stem of Z. jujuba
(Ogihara et al., 1976). Saponins are part of sugar chains which attach
themselves to a sterol or triterpene. They are known to bind with cholesterol
preventing it from being reabsorbed into the system. They are being widely
researched for cancer prevention and cholesterol control. Ogihara (1976)
developed a method for successful qualitative and quantitative determination of
saponins in Z. jujuba seeds using counter current chromatography.
The saponins isolated from the seeds of Z .jujuba include jujubosides A, B
(ZengL et al., 1987), A1 B1 and C and acetyljujuboside B (Yoshikawa et al.,
1997) and the protojujubosides A, B and B1 (Matsuda et al., 1999).
Kurihara et al. (1988) extracted the saponin, ziziphin, from the dried leaves of
Z. jujuba. It has a structure, 3-O-a-L-rhamnopyranosyl (1-2)-a-Larabinopyranosyl-20-O-
(2,3)-di-O-acetyl-a-L-rhamnopyranosyl jujubogenin.
Ikram et al. (1981) isolated a saponin from Z .jujuba leaves and stem. It was
assigned the structure 3-O- ((2-O- alpha – D – furopyranosyl – 3-O- beta – D –
glucopyranosyl) – alpha – L – arabinopyranosyl) jujubogenin. Jujubogenin was
also found in extract of Z. mauritiana leaves (Sharma and Kumar, 1982).
Saponins show adjuvant (Oda et al., 2000), haemolytic (Oda et al., 2000),
sedative (Shou et al., 2002) anxiolytic and sweetness inhibiting properties
(Kurihara et al., 1988). Jujuboside A (JuA), is also known to be a noncompetitive
inhibitor of calmodulin (Zhou et al., 1994), which is an ubiquitous,
calcium-binding protein that can bind to and regulate a multitude of different
protein targets, thereby affecting many different cellular functions. CaM
mediates processes such as inflammation, metabolism, muscle contraction,
short-term and long-term memory, and the immune response (McDowall,
2003). Jujuboside inhibition of calmodulin is thought to be linked to its
sedative properties (Zhou et al., 1994).
2.3.5 Triterpenoic acids
The following triterpenoic acids have been isolated from the fruits of Z. jujuba:
colubrinic acid, alphitolic acid, 3-O-cis-p-coumaroylalphitolic acid, 3-O-transp-coumaroylalphitolic
acid, 3-O-cis-p-coumaroylmaslinic acid, 3-O-trans-pcoumaroylmaslinic
acid, oleanolic acid, betulonic acid, oleanonic acid,
zizyberenalic acid and betulinic acid (Lee et al., 2003). Triterpenoic acids have
shown cytotoxic effects on tumour cell lines (Eiznhamer and Xu, 2004).
Triterpenoic acids have also been extracted from roots of Z. mauritiana (Kundu
et al. 1989).
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