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This study aimed to investigate the effect of astaxanthin (ASX) extracted and ASX powder from shrimp (Litopenaeus vannamei) shells on Wistar rats with Alzheimer’s disease, induced by amyloid-β (1-42) peptides. In this task, the rats were divided into eight groups: (1) Control, (2) sham operate, (3) negative control (vehicle) + Aβ1-42, (4) ASX extract+Aβ1-42, (5) commercial ASX + Aβ1-42, (6) ASX powder + Aβ1-42, (7) blank powder + Aβ1-42, and (8) vitamin E + Aβ1-42. All treatments were orally administrated for 30 days. At 14- and 29-days post injection, animals were observed in behavioral tests. On the 31st day, animals were sacrificed; the hippocampus and cortex were collected. Those two brain areas were then homogenized and stored for biochemical and histological analysis. The results showed that the Aβ1-42 infused group significantly reduced cognitive ability and increased memory loss, as assessed by the Morris water maze test, novel object recognition test, and novel object location test. Moreover, the Aβ1-42 infused group exhibited a deterioration of oxidative markers, including glutathione peroxidase enzymes (GPx), lipid peroxidation (MDA), products of protein oxidation, and superoxide anion in the cortex and the hippocampus. Meanwhile, ASX powder (10 mg/kg body weight) showed a significant reduction in cognitive and memory impairments and oxidative stress which is greater than ASX extract in the same dose of compound or vitamin E (100 mg/kg body weight). Our study indicates the beneficial properties of ASX in alleviation of cognitive functions and reducing neurodegeneration in Wistar rats induced by amyloid-β (1-42) peptides.

This study aimed to investigate the effects of phospholipid composition on the properties and bioavailability of astaxanthin-loaded liposomes using cell culture. Two mixtures of phospholipids with different proportions of phosphatidylcholine (PC, 23% and 70%) were used at various concentrations (0.8, 1.6, and 2.0% w/v) to prepare astaxanthin-loaded liposomes, which were investigated for entrapment efficiency (EE), antioxidant activity, morphology and changes in astaxanthin properties during a storage period of 8 weeks at 4°C. Furthermore, Caco-2 human colon adenocarcinoma cells were employed to examine the cellular uptake of astaxanthin-loaded liposomes. The highest EE was observed with astaxanthin-loaded liposomes containing 70% PC, and used at the concentration of 2.0% w/v. Liposomes maintained the antioxidant activity of astaxanthin. All liposomal preparations were non-toxic. Cellular uptake of astaxanthin-loaded liposomes containing 70% PC was significantly higher than that of 23% PCcontaining liposomes (p \ 0.05).

Rice flavor is a significant factor in determining quality and consumer acceptability as exemplified by scented rice, which is highly favored and commands a price premium. Sensory descriptive analysis has primarily been performed to assess rice flavor characteristics, but these studies feature only a limited lexicon for characterizing specific flavors or the range of flavor types is limited. This study was undertaken to establish a descriptive lexicon with reference standards for describing the flavor properties of a broad spectrum of rice types and use the developed lexicon to characterize which sensory attributes are most important in rice flavor quality. A rice flavor lexicon consisting of 24 descriptive notes was developed and expanded by 8 trained sensory panelists to characterize the flavor of cooked rice differing in terms of forms, types, and specialty (n = 36). Of these 24 descriptive terms, 19 were aromatic notes and 5 were fundamental tastes and oral feeling factors. Eighteen aromatic terms were significantly present in most rice samples whereas some descriptors exhibited unique characteristics of a specific-rice type. Subsequent multivariate analysis indicated that 18 descriptive terms were required to fully understand the characteristics of rice flavor in greater details. This lexicon covered a wider range of rice samples than in the previous studies and will facilitate targeting the characteristic notes important to rice processors as well as producers.

Flavor is a key factor contributing to consumer acceptance and repeat purchase of rice. Plant breeders focus on production yield and ignoring quality traits because there are no readily useable tools to evaluate quality. A systematic approach is needed for rice breeders to select rice with favorable flavor traits. Descriptive sensory analysis combined with chemical analysis provided an insight of sensory significance to interpret chemical data for a better understanding approach of rice flavor. This study was aimed to develop prediction models for sensory descriptors based on the volatile components derived from the gas chromatography-olfactometry (GC-O) that would be useful to help select rice cultivars containing a satisfactory flavor to produce improved quality in rice breeding programs. Thirteen Korean specialty rice samples were evaluated for their flavor components using descriptive analysis and GC-O. Nineteen aroma attributes in cooked specialty rice samples were evaluated by 8 trained panelists and statistically correlated to the concentration of aroma-active compounds derived from GC-O analysis. Prediction models were developed for most aroma descriptors including popcorn, cooked grain, starchy, woody, smoky, grain, corn, hay-like, barny, rancid, waxy, earthy, and sweet aroma using stepwise multiple linear regression. (E,E)-2, 4-decadienal, naphthalene, guaiacol, (E)-2-hexenal, 2-acetyl-1-pyrroline, 2-heptanone contributed most to these sensory attributes. These models help provide a quantitative link between sensory characteristics of commercial rice samples and aroma volatile components desirable in developing a rapid analytical method for use by rice breeders to screen progeny for superior flavor quality.