Synsepalum dulcificum, also called the miracle fruit, which has the sweet-inducing activity can be used as additives in food, medicine and cosmetic industries. Some selected chemical properties of miracle fruit including percentage by weight, total anthocyanin, phenolic and antioxidant content of different parts of miracle fruit as well as physicochemical analysis of seed oil, nutritional elements of fruit juice were determined in this study. The results showed that miracle fruit contains a large amount of vitamin C (40.1 mg/100 g fresh fruit weight (FW)), phenolic content (625.57 mg GAE/100 g FW), high antioxidant capacity (457.3 μmol Trolox/100 g FW) and low total sugar content (5.6 g/100 g FW), suggesting that the fruit is healthy for human consumption. According to its fatty acid composition and Triacylglycerol (TAG) profile, miracle fruit seed oil is rich in oleic and palmitic acid.

BackgroundCell disruption strategies by high pressure homogenizer for the release of recombinant Hepatitis B surface antigen (HBsAg) from Pichia pastoris expression cells were optimized using response surface methodology (RSM) based on the central composite design (CCD). The factors studied include number of passes, biomass concentration and pulse pressure. Polynomial models were used to correlate the above mentioned factors to project the cell disruption capability and specific protein release of HBsAg from P. pastoris cells.ResultsThe proposed cell disruption strategy consisted of a number of passes set at 20 times, biomass concentration of 7.70 g/L of dry cell weight (DCW) and pulse pressure at 1,029 bar. The optimized cell disruption strategy was shown to increase cell disruption efficiency by 2-fold and 4-fold for specific protein release of HBsAg when compared to glass bead method yielding 75.68% cell disruption rate (CDR) and HBsAg concentration of 29.20 mg/L respectively.ConclusionsThe model equation generated from RSM on cell disruption of P. pastoris was found adequate to determine the significant factors and its interactions among the process variables and the optimum conditions in releasing HBsAg when validated against a glass bead cell disruption method. The findings from the study can open up a promising strategy for better recovery of HBsAg recombinant protein during downstream processing.

This paper deliberates the extraction, characterization and examination of potential application of soluble polysaccharides of palm kernel cake (PKC) as a prebiotic. The PKC was defatted and crude polysaccharide was obtained through water, citric acid or NaOH extraction. The physiochemical properties of the extracted polysaccharides viz. total carbohydrates, protein content, solubility rate, monosaccharides composition, structural information and thermal properties were also determined. The extracted soluble polysaccharides were further subjected to a digestibility test using artificial human gastric juice. Finally, their prebiotic potential on two probiotics, namely ATCC 8014 and ATCC 53103 were evaluated in vitro. It was observed that PKC contained ash (5.2%), moisture (7.4%), carbohydrates (65.8%), protein (16.5%) and fat (5.1%). There were significant differences ( < 0.05) between the values of NaOH-extracted crude polysaccharides (8.73%) and that of water (3.03%) and citric acid (3.07%)-extracted polysaccharides. The extracted polysaccharides composed of mannose, galactose, glucose, arabinose, xylose and rhamanose, with highest percentage of mannose (62.49%) and galactose (25.42%) in SP. Total carbohydrate content in SCP, SCP and SCP are 57.11%, 56.94% and 50.95%, respectively. The polysaccharides from PKC in this study were found to be highly soluble (> 95%). Protein content in SCP, SCP and SCP are 0.72, 0.40 and 0.58, respectively, and the peaks which indicated the presence of protein were observed at approximately 1640 cm (amide I). FTIR spectroscopy revealed that the polysaccharides extracts were linked to and-glycosidic bonds and thermal analysis using differential scanning calorimeter (DSC) showed the main degradation temperature of SP is about 121 to 125 °C. The SP were found to be highly resistance (> 96%) to hydrolysis when subjected to artificial human gastric juice. The prebiotics potentials of the polysaccharides on probiotics in vitro demonstrated an increase in proliferation of ATCC 8014 and ATCC 53103 with decrease in the pH of the medium and producing organic acids.All the above findings strongly indicated that polysaccharides extracted from PKC, an industrial waste, have a potential to be exploited as novel prebiotics.

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A stirred tank bioreactor (STB) integrated with an expanded bed adsorption (EBA) system containing anion-exchange resin (Diaion WA30) was developed for in situ removal of acetate to increase the production of α-interferon-2b (α-PrIFN-2b) by Escherichia coli (E. coli). Although the total acetate (9.79 g/L) secreted by E. coli in the integrated STB/EBA system was higher than that in a bioreactor with dispersed resin or a conventional batch bioreactor, cell growth (14.97 g/L) and α-PrIFN-2b production (867.4 μg/L) were significantly improved owing to the high efficiency of acetate removal from the culture. The production of α-PrIFN-2b in the integrated STB/EBA system was improved by 3-fold and 1.4-fold over that obtained in a conventional batch bioreactor and a bioreactor containing dispersed resins, respectively.

Limit of detection (LOD), limit of quantification, and the dynamic range of detection of hepatitis B surface antigen antibody (anti-HBs) using a surface plasmon resonance (SPR) chip-based approach with Pichia pastoris-derived recombinant hepatitis B surface antigen (HBsAg) as recognition element were established through the scouting for optimal conditions for the improvement of immobilization efficiency and in the use of optimal regeneration buffer. Recombinant HBsAg was immobilized onto the sensor surface of a CM5 chip at a concentration of 150 mg/L in sodium acetate buffer at pH 4 with added 0.6% Triton X-100. A regeneration solution of 20 mM HCl was optimally found to effectively unbind analytes from the ligand, thus allowing for multiple screening cycles. A dynamic range of detection of ∼0.00098-0.25 mg/L was obtained, and a sevenfold higher LOD, as well as a twofold increase in coefficient of variance of the replicated results, was shown as compared with enzyme-linked immunosorbent assay (ELISA). Evaluation of the assay for specificity showed no cross-reactivity with other antibodies tested. The ability of SPR chip-based assay and ELISA to detect anti-HBs in human serum was comparable, indicating that the SPR chip-based assay with its multiple screening capacity has greater advantage over ELISA.

Miracle fruit, Synsepalum dulcificum, contains a glycoprotein known as miraculin. After consuming this glycoprotein, sour foods taste sweet and the effect lasts for up to 4 h. With increasing demand for natural and "low-calorie" sweeteners, the use of miraculin as an additive is increasing enormously in the food, medicine and cosmetic industries. In this study, we used reverse micelles formed from a sodium di (2-ethylhexyl) sulfosuccinate (AOT)/isooctane system to purify miraculin from S. dulcificum. We studied factors affecting purification performance, such as surfactant (AOT) concentration and the pH of the crude during forward extraction. During backward extraction, we examined the effects of NaCl concentration, the pH of the aqueous phase and addition of isopropanol. We found that 0.1 mol/L AOT/isooctane solution mixed with crude extract at pH 8 during the forward extraction stage and 0.5 mol/L NaCl solution at pH 11 during the backward stripping stage were optimal purification conditions, from which 22% miraculin was recovered with a purity of 94.8%.

The aims of this study were to compare the effectiveness of different drying methods and to investigate the effects of adding a series of individual protectant such as skim milk, sucrose, maltodextrin, and corn starch for preserving Lactobacillus acidophilus FTDC 3081 cells during spray and freeze-drying and storage at different temperatures. Results showed a remarkable high survival rate of 70–80% immediately after spray- and freeze-drying in which the cell viability retained at the range of 109 to 1010 CFU/mL. After a month of storage, maltodextrin showed higher protective ability on both spray- and freeze-dried cells as compared to other protective agents at 4°C, 25°C, and 40°C. A complete loss in viability of spray-dried L. acidophilus FTDC 3081 was observed after a month at 40°C in the absence of protective agent.