The data indicate bioavailability of early and late phase WBB metabolites peaking at different times during the 24 h period, which may be important for maximizing their biological activity.

Lactobacillus plantarum BM-1 isolated from a traditionally fermented Chinese meat product was found to produce a novel bacteriocin that is active against a wide range of gram-positive and gram-negative bacteria. Production of the bacteriocin BM-1 started early in the exponential phase and its maximum activity (5120 AU/mL) was recorded early during the stationary phase (16 hr). Bacteriocin BM-1 is sensitive to proteolytic enzymes but stable in the pH range of 2.0-10.0 and heat-resistant (15 min at 121°C). This bacteriocin was purified through pH-mediated cell adsorption-desorption and cationexchange chromatography on an SP Sepharose Fast Flow column. The molecular weight of the purified bacteriocin BM-1 was determined to be 4638.142 Da by electrospray ionization Fourier transform mass spectrometry. Furthermore, the N-terminal amino acid sequence was obtained through automated Edman degradation and found to comprise the following 15 amino acid residues: H 2 N-Lys-Tyr-TyrGly-Asn-Gly-Val-Tyr-Val-Gly-Lys-His-Ser-Cys-Ser. Comparison of this sequence with that of other bacteriocins revealed that bacteriocin BM-1 contains the consensus YGNGV amino acid motif near the N-terminus. Based on its physicochemical characteristics, molecular weight, and N-terminal amino acid sequence, plantaricin BM-1 is a novel class IIa bacteriocin.

Free and glycosidically bound volatile compounds in different parts of Eureka lemon were studied. Free volatile compounds were extracted by solid phase microextraction (SPME). Bound volatile compounds were isolated from juice by adsorption onto an Amberlite XAD-2 column, and then hydrolyzed by almond β-glucosidase. Both the free volatile compounds and the released aglycones were analyzed by using gas chromatography-mass spectromerty (GC-MS). Gas chromatography-olfactometry (GC-O) was also used to determine the aroma-active compounds in juice and peel. Totally 29 and 34 free volatiles were found in juice and peel, respectively. Terpenes and aldehydes were the most abundant compounds in free fractions. Four and six bound volatile compounds were found in juice and peel with a total concentration of 127.8 and 1161.52 μg/L. Benzenic and terpenic compounds were the main bound volatiles found in Eureka lemon fruit. Mannose and glucose were found as sugar moiety in juice, and glucose was found the only sugar linked to bound volatiles in peel.Keywords: eureka lemon, volatile compounds, glycosides, enzymatic hydrolysis, aroma active compounds IntroductionEureka lemon originated in America and grew widely under tropical and sub-tropical climatic conditions, including many countries such as Australia, Israel and southern China. It is a common lemon species in the world (Ford, 1942). It is called "the true 'better' lemon" and has large quantity of juice and acid content.Eureka lemon has not been got much attention. The fruit is elliptic in shape, bright yellow and medium thickness of the skin.It is more acidic than Meyer lemon, its peel is thicker, and also the juice is less than Lisbon lemon, a lemon similar to Eureka lemon.Generally speaking, Meyer lemon and Lisbon lemon are more used as juice production, cooking and eating. But the characters of Eureka lemon make it better to be a good material to produce essential oil and other aroma products. The luxuriant aroma compounds of lemon are applied in many fields. d-Limonene plays a potential role in preventing breast cancer (Miller et al., 2011), and the antioxidant activity of lemon essential oils has been confirmed (Di et al., 2010). Lemon products are also important for food industry and health care (González-Molina et al., 2010).Volatile compounds in Meyer lemon (Moshonas et al., 1972), Italian lemon (Allegrone et al., 2006) and petitgrain Eureka lemon essential oil (Baaliouamer et al., 1985) have been reported, except Eureka lemon. Many studies showed the common volatile compounds in lemon. Several studies showed that the main volatile compounds in lemon essential oil were monoterpenes, such as limonene, γ-terpinene and β-myrcene (Fan et al., 2009a;Verzera et al., 2004). Limonene was the most abundant compound in lemon. Additionally, aldehydes, ketones and esters were the other important volatile compounds in lemon (Lota et al., 2004;Moufida et al., 2003). The free volatile compounds and particular character compounds of Eureka lemon have not been reported yet. The boun...

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