ABSTRACT
Pro-inflammatory cytokines and anti-inflammatory cytokines are important mediators that regulate the inflammatory response in inflammation-related diseases. The aim of this study is to evaluate different New Zealand (NZ)-grown ginseng fractions on the productions of pro-inflammatory and anti-inflammatory cytokines in human monocytic THP-1 cells. Four NZ-grown ginseng fractions, including total ginseng extract (TGE), non-ginsenoside fraction extract (NGE), high-polar ginsenoside fraction extract (HPG), and less-polar ginsenoside fraction extract (LPG), were prepared and the ginsenoside compositions of extracts were analyzed by HPLC using 19 ginsenoside reference standards. The THP-1 cells were pre-treated with different concentrations of TGE, NGE, HPG, and LPG, and were then stimulated with lipopolysaccharide (LPS). The levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), and anti-inflammatory cytokines, such as interleukin-10 (IL-10), and transforming growth factor beta-1 (TGF-ß1), were determined by enzyme-linked immunosorbent assay (ELISA). TGE at 400 µg/mL significantly inhibited LPS-induced TNF-α and IL-6 productions. NGE did not show any effects on inflammatory secretion except inhibited IL-6 production at a high dose. Furthermore, LPG displayed a stronger effect than HPG on inhibiting pro-inflammatory cytokine (TNF-α, IL-1ß, and IL-6) productions. Particularly, 100 µg/mL LPG not only significantly inhibited the production of pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6, but also remarkably enhanced the production of anti-inflammatory cytokine IL-10. NZ-grown ginseng exhibited anti-inflammatory effects in vitro, which is mainly attributed to ginsenoside fractions (particularly less-polar ginsenosides) rather than non-saponin fractions.
Subject(s)
Cytokines/antagonists & inhibitors , Ginsenosides/pharmacology , Panax/chemistry , Plant Extracts/pharmacology , Cytokines/analysis , Cytokines/biosynthesis , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Ginsenosides/chemistry , Ginsenosides/isolation & purification , Humans , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Plant Extracts/chemistry , Plant Extracts/isolation & purification , THP-1 CellsABSTRACT
Spray-dried animal plasma sourced from bovine, porcine or other animal origin is often used as a main feed ingredient in the diets of weanling piglets to improve growth performance. The objective of this study was to determine the effect of animal plasma in diets on the performance of piglets in the post-weaning period, with and/or without pathogenic challenge, by undertaking a meta-analysis. Data were extracted from peer-reviewed reports published in scientific journals. The average initial weight of the piglets was 5.8 kg and the average initial age 19 days (2-56 days). The average duration of feeding animal plasma was 40 days. Average daily gain (ADG), feed intake (ADFI) and feed conversion ratio (FCR) were found to be 22-28 g/day, 20-27 g/day and -0.28 to 0.06 g/g. Generally, diet supplemented with spray-dried bovine plasma (SDBP) improved the ADG of the piglets and spray-dried porcine plasma (SDPP) led to increases in the ADFI. For the first week post-weaning alone, as the dietary animal plasma percentage increased there was an increase in ADG and ADFI; similarly, the latter two measures increased as weaning age increased. The evidence suggests that mainly IgG present in animal plasma prevents the binding of pathogens to the gut wall and reduces the incidence of sub-clinical infection in the post-weaning stage. Animal plasma containing IgG appears to be a useful in-feed supplement for piglets in the post-weaning phase.
Subject(s)
Animal Feed , Weight Gain , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Cattle , Diet/veterinary , Plasma , Swine , WeaningABSTRACT
Ginseng is an increasingly popular ingredient in supplements for healthcare products and traditional medicine. Heat-processed ginsengs, such as red ginseng or black ginseng, are regarded as more valuable for medicinal use when compared to white ginseng due to some unique less polar ginsenosides that are produced during heat-treatment. Although ginseng leaf contains abundant ginsenosides, attention has mostly focused on ginseng root; relatively few publications have focused on ginseng leaf. Raw ginseng leaf was steamed nine times to make black ginseng leaf using a process that is similar to that used to produce black ginseng root. Sixteen ginsenosides were analyzed during each steaming while using high-performance liquid chromatography (HPLC). The contents of ginsenosides Rd and Re decreased and the less polar ginsenosides (F2, Rg3, Rk2, Rk3, Rh3, Rh4, and protopanaxatriol) enriched during steam treatment. After nine cycles of steaming, the contents of the less polar ginsenosides F2, Rg3, and Rk2 increased by 12.9-fold, 8.6-fold, and 2.6-fold, respectively. Further, we found that the polar protopanaxadiol (PPD) -type ginsenosides are more likely to be converted from ginsenoside Rg3 to ginsenosides Rk1 and Rg5 via dehydration from Rg3, and from ginsenoside Rh2 to ginsenosides Rk2 and Rh3 through losing an H2O molecule than to be completely degraded to the aglycones PPD during the heat process. This study suggests that ginseng leaves can be used to produce less polar ginsenosides through heat processes, such as steaming.
Subject(s)
Ginsenosides/analysis , Hot Temperature , Panax/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Chromatography, High Pressure LiquidABSTRACT
The objective of this study was to evaluate the relationship among the number of bacteria, number of goblet cells, gut mucin gene expression, mucin protein and immunity protein levels of rats fed a diet containing freeze-dried ovine Ig (FD). Sprague Dawley male rats were used in a 21-days study and were fed a basal control diet (BD; no Ig) and a test diet containing freeze-dried ovine Ig (FD). Diets were isocaloric and contained the same amount of the first limiting amino acids, methionine plus cysteine. Pearson's correlation analysis was conducted on the data (stomach, ileum and colon) obtained from individual rats (n = 10) fed either casein-based diet (BD) or ovine serum Ig (FD) to evaluate the relationship between number of bacteria, number of goblet cells, gut mucin gene expression and gut mucin protein levels. Pearson's correlation analysis was then conducted with the data from the FD fed rats to evaluate the relationship among the above said variables. In the stomach content, a significant (p < .05) correlation was found between the Muc5Ac gene expression and mucosal mucin protein. In the ileum and colon, a significant (p < .05) correlation was observed among the mRNA levels of mucin (Muc2 and Muc4) genes. There was also evidence of a strong relationship (p < .05) between digesta mucin and mucosal mucin protein concentrations. A negative correlation of mucosal IgA protein concentration with total Lactobacillus (in ileum and colon) and total bacteria (in the ileum) was not evident with FD fed rats when compared to the results obtained using both BD and FD fed rats. In conclusion, this study suggests that feeding freeze-dried ovine Ig in growing rats results in a strong correlation between the number of bacteria, mucin and immunity proteins.
Subject(s)
Dietary Supplements , Gastrointestinal Microbiome/drug effects , Immunoglobulins/administration & dosage , Mucins/metabolism , Sheep/blood , Animals , Immunity, Humoral , Male , Random Allocation , Rats , Rats, Sprague-DawleyABSTRACT
OBJECTIVE: The aim of this study is to characterize the impact of additional electrical stimulation (AES) and various pre-rigor holding temperatures (for 3 h) on the ageing-potential of hot boned bovine M. longissimus lumborum (LL). METHODS: Paired LL loins from 12 bulls were hot-boned within 40 min of slaughter, immediate AES applied and subjected to various holding temperatures (5°C, 15°C, 25°C, and 35°C) for 3 h. RESULTS: AES did not accelerate the rate of rigor attainment, but the 3 h pre-rigor holding temperature did. Shear force values decreased as the pre-rigor holding temperatures increased. AES and holding for 3 h (at 25°C) resulted in higher water-holding capacity. CONCLUSION: Data confirmed that AES did not influence the various meat quality parameters in the present study, but pre-rigor holding temperature (25°C) alone or in combination with AES resulted in superior meat quality.
ABSTRACT
Recently Panax ginseng has been grown as a secondary crop under a pine tree canopy in New Zealand (NZ). The aim of the study is to compare the average content of ginsenosides from NZ-grown ginseng and its original native locations (China and Korea) grown ginseng. Ten batches of NZ-grown ginseng were extracted using 70% methanol and analyzed using LC-MS/MS. The average content of ginsenosides from China and Korea grown ginseng were obtained by collecting data from 30 and 17 publications featuring China and Korea grown ginseng, respectively. The average content of total ginsenosides in NZ-grown ginseng was 40.06 ± 3.21 mg/g (n = 14), which showed significantly (p < 0.05) higher concentration than that of China grown ginseng (16.48 ± 1.24 mg/g, n = 113) and Korea grown ginseng (21.05 ± 1.57 mg/g, n = 106). For the individual ginsenosides, except for the ginsenosides Rb2, Rc, and Rd, ginsenosides Rb1, Re, Rf, and Rg1 from NZ-grown ginseng were 2.22, 2.91, 1.65, and 1.27 times higher than that of ginseng grown in China, respectively. Ginsenosides Re and Rg1 in NZ-grown ginseng were also 2.14 and 1.63 times higher than ginseng grown in Korea. From the accumulation of ginsenosides, New Zealand volcanic pumice soil may be more suitable for ginseng growth than its place of origin.
Subject(s)
Ginsenosides/analysis , Ginsenosides/chemistry , Panax/chemistry , Panax/classification , China , Geography , Molecular Structure , New Zealand , Republic of KoreaABSTRACT
Ginseng is one of the most valuable and commonly used Chinese medicines not only in ancient China but also worldwide. Ginsenosides, also known as saponins or triterpenoids, are thought to be responsible for the beneficial effects of ginseng. In this review, we summarize recent publications on anti-diabetic studies of ginseng extracts and ginsenosides in cells, animals, and humans. It seems that the anti-diabetic effect of ginseng is positive for type 2 diabetic patients but has no significant impact on prediabetes or healthy adults. Regulation of insulin secretion, glucose uptake, anti-oxidative stress, and anti-inflammatory pathways may be the mechanisms involved with ginseng's anti-diabetic effects. Taken together, this summary provides evidence for the anti-diabetes effects of ginseng extracts and ginsenosides as well as the underlying mechanisms of their impact on diabetes.
Subject(s)
Ginsenosides/pharmacology , Ginsenosides/therapeutic use , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Panax/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Animals , Blood Glucose/drug effects , Clinical Trials as Topic , Diabetes Mellitus/drug therapy , Diabetes Mellitus/etiology , Diabetes Mellitus/metabolism , Drug Evaluation, Preclinical , Ginsenosides/chemistry , Humans , Hypoglycemic Agents/chemistry , Molecular Structure , Plant Extracts/chemistry , Treatment OutcomeABSTRACT
Immunoglobulins are major glycoproteins that modulate the immune response of gut-associated lymphoid tissue. In the present study, we sought to determine whether orally administered ovine serum immunoglobulins modulate selected indices of mucosal immune function and immune mediators in the growing rat challenged with Salmonella enteritidis. Rats were fed a casein-based basal control diet (BD; unchallenged). Three groups of rats were challenged orally with 1 x 10(7) viable S. enteritidis on day 15 of the study and were fed the BD, the BD containing freeze-dried ovine immunoglobulins (FDOI), or the BD containing autoclaved ovine immunoglobulins (AOI; negative control diet). The rats were randomly allocated to one of the four groups (n 15) and consumed their diet for 18 d. In all of the intestinal segments, the challenged rats fed either the BD or AOI diet produced higher (P<0·05) mucosal levels of interferon-g, TNFa, IgA and myeloperoxidase activity than the challenged rats fed the FDOI diet. In contrast, IL-4 and IL-10 levels were higher in the challenged FDOI-fed rats compared with the other challenged groups. The challenged FDOI-fed rats had higher (P<0·05) mucosal anti-Salmonella IgA and IgG in all of the intestinal segments except the jejunum and ileum. Generally, the challenged rats receiving the FDOI diet had significantly (P<0·05) higher mucosal mucin protein content compared with challenged rats receiving either the BD or AOI diet. In conclusion, an ovine immunoglobulin fraction positively modulated some selected indices of mucosal immune function and its mediators in growing rats challenged with S. enteritidis.
Subject(s)
Immunity, Mucosal/drug effects , Immunoglobulins/pharmacology , Salmonella Infections, Animal/immunology , Salmonella enteritidis , Administration, Oral , Animal Feed , Animals , Cytokines/analysis , Diet , Gene Expression Regulation, Enzymologic , Immunoglobulins/administration & dosage , Immunoglobulins/analysis , Intestinal Mucosa/chemistry , Intestinal Mucosa/enzymology , Intestinal Mucosa/immunology , Male , Mucins/analysis , Peroxidase/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Salmonella Infections, Animal/microbiology , Salmonella enteritidis/immunology , SheepABSTRACT
In this study, we aimed to determine whether orally administered ovine serum Ig modulate aspects of immunity and associated gut microflora in growing rats challenged with Salmonella enteritidis. The 4 groups consisted of rats fed a casein-based control diet (BD; ungavaged) and 3 groups of rats gavaged with 1 × 10(7) viable Salmonella enteritidis and fed a BD diet, a BD diet containing freeze-dried ovine Ig (FDOI), or a BD diet containing inactivated ovine Ig (IOI). The rats were randomly allocated to 1 of the 4 diets (n = 15) and consumed it for 18 d. They were orally gavaged on d 15. Phagocytic activity of peripheral blood leukocyte and lymphocyte proliferation in the presence of the concanavalin A (ConA) were greater (P < 0.05) in the ungavaged BD- and gavaged FDOI-fed rats than in the gavaged rats fed either the BD or IOI diet. ConA-stimulated Peyer's patch cells and splenocytes from the gavaged rats fed the FDOI diet produced more IFNγ, IgA, and IgG than the gavaged rats fed either the BD or IOI diet (P < 0.05). The gavaged FDOI-fed rats had higher ileal and colonic digesta and plasma concentrations of anti-Salmonella secretory sIgA and secretory sIgG (P < 0.05). DNA analysis of a denatured gradient gel electrophoresis profile revealed that 6 of 10 bands had sequence similarity to probiotic strains of bacteria in the ileum and colon of the gavaged FDOI-fed rats. In conclusion, an ovine Ig fraction modulated various indices of immune function and associated gut microflora in growing rats inoculated with Salmonella.
Subject(s)
Gastroenteritis/prevention & control , Host-Pathogen Interactions , Immunoglobulins/therapeutic use , Immunomodulation , Salmonella Infections/prevention & control , Salmonella enteritidis/immunology , Administration, Oral , Animals , Antibodies, Bacterial/blood , Antibodies, Bacterial/metabolism , Cells, Cultured , Cytophagocytosis/immunology , Gastroenteritis/immunology , Gastrointestinal Contents/chemistry , Gastrointestinal Contents/microbiology , Immunoglobulins/administration & dosage , Immunoglobulins/metabolism , Interferon-gamma/metabolism , Intestines/growth & development , Intestines/immunology , Intestines/microbiology , Leukocytes/immunology , Lymphocyte Activation/immunology , Male , Peyer's Patches/cytology , Peyer's Patches/immunology , Peyer's Patches/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Salmonella Infections/immunology , Sheep, Domestic , Spleen/cytology , Spleen/growth & development , Spleen/immunology , Spleen/metabolismABSTRACT
BACKGROUND: Ginsenosides are the unique and bioactive components in ginseng. Ginsenosides are affected by the growing environment and conditions. In New Zealand (NZ), Panax ginseng Meyer (P. ginseng) is grown as a secondary crop under a pine tree canopy with an open-field forest environment. There is no thorough analysis reported about NZ-grown ginseng. METHODS: Ginsenosides from NZ-grown P. ginseng in different parts (main root, fine root, rhizome, stem, and leaf) with different ages (6, 12, 13, and 14 years) were extracted by ultrasonic extraction and characterized by Liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Twenty-one ginsenosides in these samples were accurately quantified and relatively quantified with 13 ginsenoside standards. RESULTS: All compounds were separated in 40 min, and a total of 102 ginsenosides were identified by matching MS spectra data with 23 standard references or published known ginsenosides from P. ginseng. The quantitative results showed that the total content of ginsenosides in various parts of P. ginseng varied, which was not obviously dependent on age. In the underground parts, the 13-year-old ginseng root contained more abundant ginsenosides among tested ginseng samples, whereas in the aboveground parts, the greatest amount of ginsenosides was from the 14-year-old sample. In addition, the amount of ginsenosides is higher in the leaf and fine root and much lower in the stem than in the other parts of P. ginseng. CONCLUSION: This study provides the first-ever comprehensive report on NZ-grown wild simulated P. ginseng.
ABSTRACT
The effects of orally administered ovine serum immunoglobulin on dental plaque and associated oral immunity in cats were investigated. The two treatment groups consisted of 1) cats that were fed unsupplemented kibble (control diet) and 2) cats that were fed the same kibble but coated with a freeze-dried ovine serum immunoglobulin preparation (ovine Ig) (test diet). The adult cats were randomly allocated to one of the two diets (n = 15) and received their respective kibble for a 28-day experimental period. When compared to the ovine Ig-supplemented kibble, cats consuming the unsupplemented kibble had significantly (p < 0.05) higher dental plaque scores. Cat IgA and IgG concentrations in the saliva and serum were significantly (p < 0.05) higher for cats fed the unsupplemented kibble when compared to cats receiving the ovine Ig supplement. Similarly, myeloperoxidase activity in the saliva was significantly (p < 0.05) higher for cats fed the unsupplemented kibble when compared to cats receiving the Ig-supplement. Orally administered ovine serum Ig positively influenced oral health and oral immunity in cats as evidenced by preventing an increase of dental plaque formation, salivary and serum IgA and IgG concentrations and salivary myeloperoxidase activity.
Subject(s)
Cat Diseases/therapy , Dental Plaque/veterinary , Dietary Supplements , Immunization, Passive/veterinary , Immunoglobulins/therapeutic use , Administration, Oral , Animals , Cats , Dental Plaque/blood , Dental Plaque/immunology , Dental Plaque/therapy , Diet/veterinary , Immunoglobulins/administration & dosage , Male , Sheep , Sheep, DomesticABSTRACT
Asian ginseng (Panax ginseng) and American ginseng (Panax quinquefolium L.) are the two most important ginseng species for their medicinal properties. Ginseng is not only popular to consume, but is also increasingly popular to cultivate. In the North Island of New Zealand, Asian ginseng and American ginseng have been grown in Taupo and Rotorua for more than 15 years. There are no publications comparing the chemical constituents between New Zealand-grown Asian ginseng (NZPG) and New Zealand-grown American ginseng (NZPQ). In this study, fourteen ginsenoside reference standards and LC-MS2 technology were employed to analyze the ginsenoside components of various parts (fine root, rhizome, main root, stem, and leaf) from NZPG and NZPQ. Fifty and 43 ginsenosides were identified from various parts of NZPG and NZPQ, respectively, and 29 ginsenosides were found in both ginseng species. Ginsenoside concentrations in different parts of ginsengs were varied. Compared to other tissues, the fine roots contained the most abundant ginsenosides, not only in NZPG (142.49 ± 1.14 mg/g) but also in NZPQ (115.69 ± 3.51 mg/g). For the individual ginsenosides of both NZPG and NZPQ, concentration of Rb1 was highest in the underground parts (fine root, rhizome, and main root), and ginsenoside Re was highest in the aboveground parts (stem and leaf).
Subject(s)
Forests , Ginsenosides/analysis , Panax , Plant Roots , Ginsenosides/metabolism , New Zealand , Panax/chemistry , Panax/growth & development , Plant Roots/chemistry , Plant Roots/growth & development , Species SpecificityABSTRACT
In this study, our aim was to determine whether orally administered ovine serum Ig improved growth performance, organ weights, and gut morphology in growing rats and whether the method of manufacture of ovine serum Ig affected its bioactivity. Ninety Sprague-Dawley male rats were used in a 21-d growth study and were fed a basal control diet (BD; no Ig) and 5 test diets: spray-dried porcine plasma (SDPP), freeze-dried ovine Ig (FDOI), 2 concentrations of spray-dried ovine Ig (SDOI(100) and SDOI(150)), and inactivated ovine Ig (IOI). Diets were isocaloric and contained the same amount of the first limiting amino acids, methionine plus cysteine. The body weight gain:feed ratio was higher (P < 0.05) for the FDOI-fed rats than for the BD- and IOI-fed groups. FDOI rats had higher jejunum (P < 0.05) and colon weights (P < 0.05) at the end of the study than rats in the BD group. Compared with the SDOI(100)-fed group, the FDOI group supported higher (P < 0.05) duodenum and colon weights. For gut morphology, the FDOI and the BD and IOI groups differed (P < 0.05). The FDOI-fed rats had longer (P < 0.05) villi and greater villi surface areas in the duodenum, jejunum, and ileum than the rats fed SDOI(100). An ovine Ig fraction selectively improved growth performance, organ weight, and gut morphology in growing rats. Compared with spray-drying, a freeze-drying procedure appears to preserve a higher degree of immunological activity.
Subject(s)
Immunoglobulins/pharmacology , Intestines/drug effects , Organ Size/drug effects , Administration, Oral , Animals , Body Weight , Diet , Enzyme-Linked Immunosorbent Assay , Growth , Immunoglobulins/administration & dosage , Immunoglobulins/blood , Intestines/anatomy & histology , Male , Rats , Rats, Sprague-Dawley , SheepABSTRACT
Immunoglobulin (Ig) is the one of the main anti-infective components of blood, colostrum and breast milk. It is the unique glycoprotein that defends the body from harmful bacteria, viruses and other environmental pathogens by either binding to them or by forming an encapsulating barrier. The expansion of antimicrobial and immunomodulatory products from natural sources for dietary supplementation in both animals and humans is an ever growing and thriving area of research. Purified Ig from sheep serum (ovine serum Ig) is one such candidate product. Recent work has shown the various biological effects of oral Ig in different animal models including its effect on growth, immunity, intestinal growth and gut barrier function. The objective of this paper is to review the results of recent studies demonstrating the effects of oral Ig in both pathogenic and non-pathogenic animal models and to suggest a possible mechanism of its action. Overall, purified oral Ig improves growth of healthy (and challenged) rats and defends against enteric infection by immunomodulation, mucin protein and/or modification of commensal microbial composition. The findings contribute to knowledge of how orally administered ovine Ig can influence and enhance key indicators of gut function and overall growth performance in an animal model.
Subject(s)
Animal Welfare , Immunoglobulins/pharmacology , Immunoglobulins/therapeutic use , Administration, Oral , Animal Diseases/prevention & control , Animals , Gastrointestinal Microbiome/drug effects , Growth/drug effects , Immunity/drug effects , Immunoglobulins/administration & dosage , Microbiota/drug effects , Rats , SheepABSTRACT
The objective of this study was to create various pH/temp decline rates in hot-boned bull beef M. longissimus lumborum (LL) through a combination of electrical stimulation (ES) and pre-rigor holding temperature. The relationship between the pre-rigor interventions, the activities of µ-calpain and small heat shock proteins (sHSP), and the impacts on meat product quality were determined. Paired LL loins from 13 bulls were hot-boned within 40 min of slaughter, immediately ES and subjected to various holding temperatures (5, 15, 25, and 35°C) for 3 hr. The rate of muscle pH decline, sarcomere length, shear force, and proteolysis of muscle proteins were measured. ES-25°C had a longer sarcomere length compared to non-electrical stimulation samples. ES-25°C and ES-35°C samples had lower shear force values, higher µ-calpain activity and higher desmin, troponin-T, and sHSP degradation. The above findings suggest that pH/temp decline rates created in hot-boned muscle impacted muscle protein proteolysis by increasing the activity of proteases and degradation of sHSP.
Subject(s)
Calpain/analysis , Electric Stimulation , Food Quality , Heat-Shock Proteins/analysis , Muscle, Skeletal/metabolism , Red Meat/analysis , Temperature , Animals , Cattle , Desmin/metabolism , Hydrogen-Ion Concentration , Male , Peptide Hydrolases/metabolism , Proteolysis , Sarcomeres/pathology , Shear Strength , Time Factors , Troponin T/metabolismABSTRACT
The objective of this study was to determine the effect of two different freezing rate then thaw-aging regimens on the quality attributes of lamb loins. The loins were randomly allocated to one of five different freezing/thawing/aging regimes: fast-(FF1A0) and slow-(SF1A0) frozen only; fast-(FF1A2) and slow-(SF1A2) frozen then thaw-aged for 14 days; aged for 14 days never frozen (A2). FF1A2 samples had a significantly higher water-holding capacity compared to the slow frozen regardless of further aging periods. FF1A2 samples had lower (p < 0.05) shear force values than A2 and higher (p < 0.05) water-holding capacity compared to the SF1A2. Fast freezing resulted in more intracellular cryo-damage, whereas slow freezing resulted in extracellular cryo-damage. FF1A0 and SF1A0 samples had lower (p < 0.05) myofibrillar proteins degradation. This study demonstrated that fast freezing then thaw-aging can result in an improved water-holding capacity and tenderness through the minimization of extracellular ice crystal formation, reduction in purge and drip losses, and improved proteolysis in thawed lamb.
Subject(s)
Food Preservation/methods , Food Quality , Freezing , Meat , Animals , Freezing/adverse effects , Meat/analysis , Muscle Proteins/metabolism , Muscle, Skeletal/chemistry , Muscle, Skeletal/pathology , Proteolysis , Shear Strength , Sheep , Time Factors , Water/analysisABSTRACT
BACKGROUND: KCNQ channels have been widely studied in the nervous system, heart and inner ear, where they have important physiological functions. Recent reports indicate that KCNQ channels may also be expressed in portal vein where they are suggested to influence spontaneous contractile activity. The biophysical properties of K+ currents mediated by KCNQ channels resemble a current underlying the resting K+ conductance and resting potential of pulmonary artery smooth muscle cells. We therefore investigated a possible role of KCNQ channels in regulating the function of pulmonary arteries by determining the ability of the selective KCNQ channel blockers, linopirdine and XE991, to promote pulmonary vasoconstriction. METHODS: The tension developed by rat and mouse intrapulmonary or mesenteric arteries was measured using small vessel myography. Contractile responses to linopirdine and XE991 were measured in intact and endothelium denuded vessels. Experiments were also carried out under conditions that prevent the contractile effects of nerve released noradrenaline or ATP, or block various Ca2+ influx pathways, in order to investigate the mechanisms underlying contraction. RESULTS: Linopirdine and XE991 both contracted rat and mouse pulmonary arteries but had little effect on mesenteric arteries. In each case the maximum contraction was almost as large as the response to 50 mM K+. Linopirdine had an EC50 of around 1 microM and XE991 was almost 10-fold more potent. Neither removal of the endothelium nor exposure to phentolamine or alpha,beta-methylene ATP, to block alpha1-adrenoceptors or P2X receptors, respectively, affected the contraction. Contraction was abolished in Ca2+-free solution and in the presence of 1 microM nifedipine or 10 microM levcromakalim. CONCLUSION: The KCNQ channel blockers are potent and powerful constrictors of pulmonary arteries. This action may be selective for the pulmonary circulation as mesenteric arteries showed little response. The results imply that the drugs act directly on smooth muscle cells and contraction requires voltage-dependent Ca2+ influx. It is concluded that the drugs probably act by blocking KCNQ channels in pulmonary artery myocytes, leading to membrane depolarization and Ca2+ influx through L-type Ca2+ channels. This implies a functional role for KCNQ channels in regulating the resting membrane potential of pulmonary artery myocytes.
Subject(s)
Endothelium, Vascular/physiology , KCNQ Potassium Channels/antagonists & inhibitors , KCNQ Potassium Channels/physiology , Muscle Contraction/physiology , Potassium Channel Blockers/administration & dosage , Pulmonary Artery/physiology , Vasoconstriction/physiology , Animals , Anthracenes/administration & dosage , Endothelium, Vascular/drug effects , In Vitro Techniques , Indoles/administration & dosage , Male , Mice , Mice, Inbred BALB C , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Muscle, Smooth/physiology , Pyridines/administration & dosage , Rats , Rats, Sprague-Dawley , Vasoconstriction/drug effectsABSTRACT
The objective of our study was to evaluate the combined effects of ageing period and different freezing rates on meat quality attributes of beef loins. Pairs of loins (M. longissimus at 1 day post mortem) from 12 carcasses were divided into four equal portions and randomly assigned to four ageing/freezing treatments (aged only, frozen only, and 3 or 4 weeks ageing at -1.5°C then frozen). Two freezing methods (fast freezing by calcium chloride immersion or slow freezing by air freezer at -18°C) were applied to the loin sections. Fast freezing had no effect on shear force (P>0.05), but significantly improved the water-holding capacity of the aged/frozen loins by reducing purge and drip losses. Ageing-then-freezing significantly improved shear force values of loins compared to both the aged only and frozen only loins. These observations suggest that fast freezing will add more value to the aged/frozen/thawed meat by minimising the amount of water-loss due to the freezing/thawing process.
Subject(s)
Food Handling/methods , Freezing , Red Meat/analysis , Stress, Mechanical , Water , Animals , Calcium Chloride , Cattle , Cold Temperature , Humans , Paraspinal Muscles , Time FactorsABSTRACT
The objective of the present study was to evaluate the relationship between small heat shock proteins (sHSP) degradation and tenderness development of beef loins at different ultimate pH (pHu). A total of twelve loins (M. longissimus dorsi) from steers were obtained at 1 day post mortem. Shear force and proteolysis of each loin were analyzed at 1 and 28 days post mortem. The loins at intermediate pHu (5.8 to 6.0) showed more variation in tenderness compared to the loins at low pHu (<5.8), where few samples were still tough (>10kgF) at 28days. The intact sHSP20 was more pronounced (P<0.05) in the intermediate pHu loin compared to the low pHu counterpart. Further, high correlations between the degradation of both sHSP and myofibrillar proteins were observed (e.g. r=0.94; degraded sHSP27 and degraded desmin). The result of this study suggests that the extent of sHSP degradation could be an indicator of myofibrillar protein degradation and tenderness.
Subject(s)
Heat-Shock Proteins, Small/chemistry , Meat/analysis , Muscle Proteins/chemistry , Muscle, Skeletal/chemistry , Proteolysis , Stress, Mechanical , Animals , Cattle , Desmin/chemistry , Hydrogen-Ion Concentration , Male , Myofibrils/chemistryABSTRACT
The study was conducted to investigate whether oral administration of Korean ginseng powders can modulate gut microbiota as well as intestinal mucin production at the translational and transcriptional levels in the ileum of the growing rat. Thirty individually caged Sprague-Dawley male rats were allocated to three groups (n = 10) and fed for 21 days either a basal control diet or one of the two treatment diets each containing white or red Korean ginseng (WG or RG) powder. Bacterial DNA was extracted from ileal digesta and subjected to quantitative real-time PCR (qPCR) using primers for total bacteria, Lactobacillus, Bifidobacteria, Escherichia coli, Bacteroides, and Clostridium strains. The qPCR results showed that consumption of WG or RG powder significantly increased the number of total bacteria and Lactobacillus strains compared to the control group. Consumption of WG powder increased mRNA expression of the Muc2 gene in the small intestine compared to the control group. There was no effect of WG or RG on the small intestinal digesta mucin content. Correlation analysis showed that expression of the Muc2 gene was significantly associated with the number of total bacteria (r = 0.52, P < 0.05) and Lactobacillus strains (r = 0.53, P < 0.05), respectively. Furthermore, the number of Lactobacillus strains was significantly correlated with the number of total bacteria (r = 0.87, P < 0.05). Consumption of the WG powder modulated the intestinal ecosystem of the growing rat and intestinal mucin gene expression.