Development and Optimization of Black Rice (Oryza sativa L.) Sourdough Fermented by Levilactobacillus brevis LUC 247 for Physicochemical Characteristics and Antioxidant Capacity.

This study used Levilactobacillus brevis LUC 247 to ferment black rice sourdough, made into Type III black rice sourdough powder to produce black rice sourdough bread. The composition analysis, antioxidant capacity, and storage stability of the black rice sourdough bread with different proportions of black rice powder (0-60%) and fermented for different lengths of time (0-48 h) were discussed. The results showed that the black rice sourdough had the maximum lactic acid bacteria count (9 Log CFU/g) during 12 to 36 h of fermentation. The titratable acid, lactic acid, and acetic acid yields increased with the fermentation time and the proportion of black rice powder. The total anthocyanin content and antioxidant capacity increased with the fermentation time. The hardness and chewiness of the black rice sourdough bread were positively correlated with the black rice sourdough powder content and increased with storage time. In addition, the growth of fungi was significantly slowed as the additional level of black rice sourdough powder increased.

Phenolic acids identified in sorghum distillery residue demonstrated antioxidative and anti-cold-stress properties in cultured tilapia, Oreochromis mossambicus.

This study aimed to identify the bioactive compounds and evaluate the anti-cold-stress function of the sorghum distillery residue (SDR) using tilapia as an alternative animal model. The highest contents of water-soluble bioactive compounds in SDR were polyphenols, followed by tannins, anthocyanins, and flavonoids. SDR was extracted with double-distilled water, 95% ethanol, and ethyl acetate, separately. The ethanol extract (SDR-E) yielded the highest polyphenol content [15.03 mg/g of SDR dry weight (dw)], of which the EC50 value of R,R-diphenyl-ß-picrylhydrazyl (DPPH) radical scavenging efficiency was 0.56 ± 0.04 mg/mL. The SDR-E suppressed the oxidation of low-density lipoproteins (LDLs) more efficiently than that of other extracts. Tilapia fed a diet containing 3.6% SDR-E decreased accumulative mortality during cold stress, of 46.2%. The accumulative morality of the control was 92.9%. The phenolic acids identified in SDR included gallic acid (0.36 ± 0.08 mg/g of SDR dw), 3,4-dihydroxybenzoic acid (0.16 ± 0.12 mg/g of SDR dw), and 4-hydroxybenzoic acid (0.49 ± 0.23 mg/g of SDR dw). Diets supplemented with 0.5% 4-hydroxybenzoic acid fed to tilapia showed a lower mortality rate than that fed 1.0% 4-hydroxybenzoic acid, comparable to that of the tilapia fed 20% SDR. The latter showed lower mortality than that of the control. These results suggested that 4-hydroxybenzoic acid is one of the major anti-cold-stress compounds in SDR.

LDL oxidation, antioxidant capacity and growth of cultured grey mullet ( Mugil cephalus ) fed dietary sorghum distillery residue pretreated with polyethylene glycol.

Dietary sorghum distillery residue (SDR) showed antioxidant and blood thinning effects on grey mullet during winter, but inhibited their growth. The objective of this study was to establish a preliminary treatment of the dietary SDR with polyethylene glycol (PEG), a tannin-binding agent, to enhance growth and blood antioxidant capacity of grey mullet ( Mugil cephalus ) feed. The feeding trial was carried out from June to November. The water temperature was between 25 and 30 degrees C; the specific growth rate of mullet was reduced significantly by feeding diet containing 20% SDR in comparison to fish fed the control diet or diet containing 20% SDR and PEG. In the period of October-November, the water temperature decreased to 19-25 degrees C; the specific growth rates of the 20% SDR-PEG group and the 20% SDR group were 0.13 and 0.19% day(-1), respectively, significantly higher than those fed the control diet (0.07% day(-1)). Feeding with 20% SDR or 20% SDR-PEG diets resulted in prolonged lag phase of low-density lipoprotein (LDL) oxidation compared to fish fed the control diet. The total antioxidant capacity of the plasma of the grey mullet fed 20% SDR-PEG was 1.24 mmol/L, significantly higher than those in the fish fed 20% SDR diet (0.84 mmol/L) or the control (0.72 mmol/L). In vivo observations found that preliminary treatment of SDR with PEG eliminated the endogenous undesirable growth inhibitory factors but maintained its protective effects against LDL oxidation in blood and improved the total antioxidant capacity and cold adaptation of grey mullet. The ethanol extract of SDR contained 31.9 +/- 7.8 mg/g gallic acids equivalent. The concentration needed to scavenge 50% of the DPPH radicals (IC(50)) was 0.86 mg/mL. Increased gallic acid equivalent and decreased IC(50) of DPPH scavenging activity of SDR fed to fish increased the total antioxidant capacity in blood plasma of grey mullet significantly.