Enhanced thermal stability of green banana starch by heat-moisture treatment and its ability to reduce body fat accumulation and modulate gut microbiota.

The physicochemical properties (including morphology, pasting, and thermal properties) of resistant starch (RS) in green banana starch were analyzed after the heat-moisture treatment in the presence of citric acid (CAHMT) at different temperatures. Moreover, this study evaluated whether the administration of CAHMT banana starch could reduce body fat accumulation and modulate gut microbiota. Our results demonstrated that the CAHMT process (90 °C) resulted in a higher retention (80.9%) and thermal stability of RS, alteration in the crystalline structure of starch from B-type to A-type, and increased solubility (27.9-fold) and gelatinization temperatures (from 66.26-78.89 °C to 81.48-92.11 °C). A reduction in swelling power (-57.7%) and a loss of pasting viscosity were also noted. Even after a 30 min boil, the retention rate of residual RS (CAHMT at 90 °C) was up to 50% (4.3-fold higher than the control). Rats fed the CAHMT banana starch resulted in significantly (p < 0.05) lower total visceral fat (-18.1%) and Firmicutes to Bacteroidetes ratio as well as higher total fecal short chain fatty acids. The CAHMT process at 90 °C enhanced the thermal stability of banana RS allowing a wider range of applications in functional foods.

Compositional and proteomic analyses of genetically modified broccoli (Brassica oleracea var. italica) harboring an agrobacterial gene.

Previously, we showed improved shelf life for agrobacterial isopentenyltransferase (ipt) transgenic broccoli (Brassica oleracea var. italica), with yield comparable to commercial varieties, because of the protection mechanism offered by molecular chaperones and stress-related proteins. Here, we used proximate analysis to examine macronutrients, chemical and mineral constituents as well as anti-nutrient and protein changes of ipt-transgenic broccoli and corresponding controls. We also preliminarily assessed safety in mice. Most aspects were comparable between ipt-transgenic broccoli and controls, except for a significant increase in carbohydrate level and a decrease in magnesium content in ipt-transgenic lines 101, 102 and 103, as compared with non-transgenic controls. In addition, the anti-nutrient glucosinolate content was increased and crude fat content decreased in inbred control 104 and transgenic lines as compared with the parental control, "Green King". Gel-based proteomics detected more than 50 protein spots specifically found in ipt-transgenic broccoli at harvest and after cooking; one-third of these proteins showed homology to potential allergens that also play an important role in plant defense against stresses and senescence. Mice fed levels of ipt-transgenic broccoli mimicking the 120 g/day of broccoli eaten by a 60-kg human adult showed normal growth and immune function. In conclusion, the compositional and proteomic changes attributed to the transgenic ipt gene did not affect the growth and immune response of mice under the feeding regimes examined.

Improvement in antioxidant activity, angiotensin-converting enzyme inhibitory activity and in vitro cellular properties of fermented pepino milk by Lactobacillus strains containing the glutamate decarboxylase gene.

BACKGROUND: The purpose of this study was to evaluate the functional potential of fermented pepino extract (PE) milk by Lactobacillus strains containing the glutamate decarboxylase (GAD) gene. Three Lactobacillus strains were selected, including L. brevis BCRC 12310, L. casei BCRC 14082 and L. salivarius subsp. salivarius BCRC 14759. The contents of free amino acids, total phenolics content, total carotenoids and the associated functional and antioxidant abilities were analyzed, including angiotensin-converting enzyme (ACE) inhibition activity, 1,1-diphenyl-2-picylhydrazyl (DPPH) radical-scavenging ability and oxygen radical absorbance capacity (ORAC). Cell proliferation of fermented PE milk was also evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: Compared to the unfermented PE, fermented PE milk from Lactobacillus strains with the GAD gene showed higher levels of total phenolics, γ-aminobutyric acid, ACE inhibitory activity, DPPH, and ORAC. The viability of human promyelocytic leukemia cells (HL-60) determined by the MTT method decreased significantly when the cells were incubated with the PE and the fermented PE milk extracts. CONCLUSION: The consumption of fermented PE milk from Lactobacillus strains with the GAD gene is expected to benefit health. Further application as a health food is worthy of investigation. © 2012 Society of Chemical Industry.