Fiber characteristics of pork muscle exhibiting different levels of drip loss

The present study aimed to investigate the fiber characteristics of pork muscle exhibiting different levels of drip loss during storage. The samples were taken from Longissimus dorsi muscle to evaluate drip loss (n = 100). Fifteen muscles per group (low and high drip loss) were selected to evaluate the histological characteristics at 0 and 72 h of storage time. The statistical analysis revealed that a high drip loss group had greater endomysium thickness than a low drip loss group at 0 h of storage time (P < 0.05). There were no significant differences in total number of fibers, fiber diameter, fiber area and perimysium thickness at 0 h of storage time (P > 0.05). At 72 h of storage time, a high drip loss was evident in higher total number of fibers (P < 0.01), but smaller fiber diameter (P < 0.05), fiber area (P < 0.01) and endomysium thickness (P < 0.01) than a low drip loss group. There was no significant difference in perimysium thickness (P > 0.05). In conclusion, drip loss might be affected by muscle structural characteristics during storage.     

Expression level of the cytochrome P450c21 (CYP21) protein correlating to drip loss in pigs

Drip loss is an important meat quality trait of fresh meat affecting economic losses. The cytochrome P450c21 (CYP21) protein has a role on cortisol production and depends on stress. This might affect meat quality. The present study aimed to investigate the expression of CYP21 protein in correlation with drip loss. The samples were taken from the Longissimus dorsi muscle to evaluate drip loss (n = 300). Five muscles per group (low and high drip loss) were selected to evaluate CYP21 protein expression levels. Statistical analysis revealed that CYP21 protein expression levels were significantly difference between the drip loss groups. The high drip loss group had higher CYP21 protein expression levels than the low drip loss group (P < 0.05). Moreover, the high drip loss group had higher optical density values of the CYP21 protein band than the low drip loss group (P < 0.05). In conclusion, the expression of CYP21 protein will provide the basis for information and better understanding of the mechanisms related to drip loss in pork. Further study is warranted to validate these results in other populations.     

Use of Rice Husk Ash as an Admixture to Remove Chromium from a Tannery Waste

This laboratory-scale study explored the use of rice husk ash (RHA) as an admixture to stabilize and solidify the waste sludge from a chrome-tanning process. Various ratios of RHA and tannery sludge were used, ranging from 0.25 to 1.0 by weight of the cement content, resulting in an experimental matrix of 16 runs. It was observed that although the compressive strength of solidified sludge improved at longer curing times, the increase was moderate after 7 days of curing. In addition, higher RHA and/or sludge ratios progressively reduced the strength of the samples. On the other hand, curing time had a positive effect on chromium leachability since the leaching concentration decreased considerably with an increase in curing time, up to 28 days. Furthermore, both the RHA and/or sludge content affected leachability, producing acceptable results, from a Thai regulatory perspective, at ratios of 0.50 or lower. Finally, the solidified sludge can be disposed of in a secure landfill and/or used as a construction material in a number of applications.     

Specific immunomodulatory and secretory activities of stevioside and steviol in intestinal cells

Stevioside, isolated from Stevia rebaudiana, is a commercial sweetener. It was previously demonstrated that stevioside attenuates NF-kappaB-dependent TNF-alpha and IL-1beta synthesis in LPS-stimulated monocytes. The present study examined the effects of stevioside and its metabolite, steviol, on human colon carcinoma cell lines. High concentrations of stevioside (2-5 mM) and steviol (0.2-0.8 mM) decreased cell viability in T84, Caco-2, and HT29 cells. Stevioside (2 mM) potentiated TNF-alpha-mediated IL-8 release in T84 cells. However, steviol (0.01-0.2 mM) significantly suppressed TNF-alpha-induced IL-8 release in all three cell lines. In T84 cells, steviol attenuated TNF-alpha-stimulated IkappaB --> NF-kappaB signaling. Chloride transport was stimulated by steviol (0.1 mM) > stevioside (1 mM) at 30 min. Two biological effects of steviol in the colon are demonstrated for the first time: stimulation of Cl(-) secretion and attenuation of TNF-alpha-stimulated IL-8 production. The immunomodulatory effects of steviol appear to involve NF-kappaB signaling. In contrast, at nontoxic concentrations stevioside affects only Cl(-) secretion.     

Antioxidant Activities and Characterization of Polyphenols from Selected Northern Thai Rice Husks: Relation with Seed Attributes

Rice production generates a significant amount of agricultural waste. This study aimed to give results related to the existence of antioxidant phenols in agricultural waste of selected Northern Thai rice varieties. The antioxidant activities, contents of total flavonoids and phenolic compounds in the ethanolic rice husk extract were evaluated. The highest antioxidant activities were found in the variety PES1CMU, with 2,2?-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid and 2,2-diphenyl-1-picrylhydrazyl as 679.66 and 4.16 mmol/(L·g) trolox equivalent, respectively, ferric reducing antioxidant power as 0.87 mmol/(L·g) Fe²⁺, total phenolic content as 29.90 mmol/(L·g) gallic acid and total flavonoid content as 12.16 mg/g catechin equivalent. Polyphenol compounds were identified mainly by standard polyphenols using the liquid chromatography mass spectrometry, with the highest contents of phytic acid, o-coumaric acid, naringin and kaempferol. The non-glutenous and wetland ecotypes of rice husk samples were the richest in antioxidant activities and polyphenol contents characterized by using principal component analysis. The glutenous rice husk contained higher antioxidant activities than the rest. Interestingly, quercetin is a significant phenolic compound that positively correlated with the overall antioxidant activities of rice husk. This finding will be relevant for future application of rice husk antioxidant components in the production of functional ingredients as well as for the food and pharmaceutical industries.