The three ripening stages of june plum (A) and carambola (B) used for analysis. 

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... the other hand, june plum ( Spondias dulcis L.) was introduced to Jamaica in 1782, and the fruit is a drupe similar to mango (in the related genus Mangifera ), 4 to 10 cm in length with an ovoid or oblong shape which ripens yellow or orange and has a single, spiny and fibrous seed. The flavor varies from acid to sweet and has a pineapple like aroma. Beside its characteristics and large use in the Caribbean and Asian countries, little is known on june plum biochemistry and physiology. Except few unpublished data, no referenced work is reporting the variation of the biochemical compounds during the ripening of june plum except of that of Emanuel and Benkeblia (2011) who reported the variation of reducing and total sugars, total phenolics content and chlorophylls during different ripening stages, while total phenolics were also reported by few authors (Hossein et al., 2008; Kubola et al., 2011). Therefore and to fill that gap, the objective of this experimental work was to assess the variability in the levels of the different sugars found in these two fruits during different ripening stages. Fruits of carambola ( Averrhoa carambola L.) and june plum ( Spondias dulcis L.) were harvested from the Botany Garden, Department of Life Sciences, UWI, Mona Campus. The fruits were harvested at three different ripening (mature-green, mid-ripe and ripe) stages, although the commercial ripening stages are stage 2 and/or stage 3 (Fig. 1). Sugars were extracted by the method of Benkeblia and Varoquaux (2003). Briefly, frozen samples (5 g) were homogenized in 50 ml of aqueous ethanol (70%) containing a small amount of calcium carbonate (0.5 g L -1 ). The homogenate was boiled under reflux in a water bath for 15 min and filtered. The residue was extracted three times with aqueous ethanol and one time with water in the same conditions. The extracts were combined and made up to 300 ml with distilled water. An aliquot of the solution (50 ml) was concentrated to dryness under vacuum at 35°C using a rotavapor. This dry concentrate was re-dissolved in 5 ml of water, and an aliquot of 1 ml was filtered through a 0.45 mm filter and analyzed by HPAEC. Sugars and FOS were separated on an HPLC- carbohydrate column PA1, Carbo Pac (Sunnyvale, CA, USA) with a Dionex Bio LC series HPLC (Sunnyvale, CA, USA) and pulsed amperometric detector (PAD). The gradient was established by mixing eluent A (150 mM NaOH) with eluent B (500 mM acetate-Na in 150 mM NaOH) in two ways. System I: 0-1 min, 25 mM; 1-2 min, 25-50 mM; 2-20 min, 50-200 mM, 20-22 min, 500 mM; 22-30 min, 25 mM. System II: 0-1 min, 25 mM; 1-2 min, 25-50 mM; 2-14 min, 50-500 mM; 14-22 min, 500 mM; and 22-30 min, 25 mM. The established gradient of mixing eluent A with eluent B was: 0-1 min, 95% A-5% B; 1-2 min, 80% A-20% B; 2-20 min, 60% A-40% B; 20-22 min, 100% B; 22-30 min, 95% A-5% B. The flow rate through the column was 1.0 ml min -1 . The applied PAD potentials for E1 (500 ms), E2 (100 ms) and E3 (50 ms) were 0.01, 0.60 and -0.60 V, respectively, and the output range was 1°C. Samples (25 L) were injected using an auto-sampler (Intelligent auto-sampler, model AS-4000, Hitachi Ltd., Tokyo, Japan). All determinations were run in 5 replications for each ripening stage (n=5, 5 samples from 5 different fruits). The data were analyzed statistically by comparison of means by one-way ANOVA test and determination of least significant difference (LSD at p ≤ 0.05) using GraphPad Instat 3.06 (GraphPad Software Inc., San Diego, CA). Glucose content varied similarly in both carambola and june plum fruits. Glucose decreased during stage 2 from 62.20 to 45.63 mg g -1 DW, and from 37.44 to 28.92 mg g -1 DW, in carambola and june plum, respectively (Fig. 2). During stage 3, glucose increased to 67.95 and 39.60 mg g -1 DW in carambola and june plum, respectively. Fructose content varied similarly and decreased during stage two from 84.65 to 61.36 mg g -1 DW, and from 40.29 to 37.24 mg g -1 DW in carambola and june plum, respectively. During stage 3, glucose increased to 92.83 and 45.78 mg g -1 DW in carambola and june plum, respectively. On the other hand, sucrose showed different variation and decreased ...