Does dietary supplementation with lettuce seed oil enhance broiler performance, immunity, lipid profile, liver and kidney functions, antioxidant parameters, and intestinal microbiota?

The aim of this research was to evaluate the influence of lettuce seed oil (LSO) on the performance, carcass yield, kidney and liver indices, immunity, lipid profile, and cecal microbiota of fattening chicks. A total of 200, 7-day-old Cobb-500 were distributed into 5 experimental groups; each group contained 5 replicates with 8 birds each. The first group 1) the basal diet (only); 2) the basal diet plus lettuce seed oil (0.50 mL/kg); 3) the basal diet plus lettuce seed oil (1.00 mL/kg); 4) the basal diet plus lettuce seed oil (1.50 mL/kg); and 5) the basal diet plus lettuce seed oil (2.00 mL/kg). No significant effect was observed on growth performance, carcass traits, or kidney function at any level of oil. But, liver function was significantly affected due to LSO levels. Serum lipid profiles (total cholesterol-TC, triglyceride-TG, low-density lipoprotein-LDL, and very low-density lipoprotein-VLDL) were significantly reduced by using LSO levels compared to the control group. Dietary LSO significantly increased immunological and antioxidant parameters, except for malondialdehyde-MDA, which was reduced. On the other hand, the cecal microbiota was significantly improved by LSO additives. It was concluded that the dietary supplementation of LSO had beneficial effects on liver and kidney functions, lipid profile, immunity, antioxidant parameters, and the bacteriology of fattening chicks.

Improving the Quality of Turkey Meat via Storage Temperature, Packaging Atmosphere, and Oregano (Origanum vulgare) Essential Oil Addition

The provision of plentiful good-quality food is a primary issue in the modern world. This work was planned to study the influence of packaging atmosphere and oregano (Origanum vulgare) essential oil addition [(vacuum packaging: T1 or modified atmosphere packaging or T2 (CO2/N2 = 4:6) or T3, T2 with oregano essential oil (T2 + EO)] under various storage temperatures (0, 5, 10, and 15 °C) on the control of survival of Escherichia coli O157:H7 and associated spoilage flora in sliced smoked turkey meat. The pathogen increased by only <1.0 log colony-forming unit (CFU)/g under all packaging and temperature combinations. Moreover, T1, T2, and T3 exerted practically similar inhibitory activity against the pathogen and dominating bacteria, with a relatively low growth of E. coli O157:H7 in sliced smoked turkey during the shelf life under all storage regimes compared to the control. However, the pathogen survival was highest on the sliced smoked turkey under T1, decreasing by only 0.67, 0.74, 0.63, and 1.30 log CFU/g within 37 days if kept at 0, 5, 10, and 15 °C, respectively. Under T2 and the same condition, E. coli O157:H7 in the product declined by only 0.31, 0.50, 0.72, and 1.10 log CFU/g within 37 days of storage, respectively. In the T3 samples, the pathogen was reduced by only 0.33, 0.67, 1.72, and 3.46 log CFU/g through 37 days of storage, respectively. Under T3 were E. coli O157:H7 populations in smoked turkey eliminated (negative by enrichment) under all conditions (after 129, 95, 95, and 43 days maintained at 0, 5, 10, and 15 °C, respectively) compared with other packaging temperature combinations. Thus, T3 contributed to developing ready-to-eat smoked turkey with enhanced product quality and eliminating the pathogen.

Growth, carcass characteristics, meat quality, and microbial aspects of growing quail fed diets enriched with two different types of probiotics (Bacillus toyonensis and Bifidobacterium bifidum)

The present investigation aimed to explore the impact of dietary graded levels of 2 types of probiotic bacteria (Bacillus toyonensis [BT] and Bifidobacterium bifidum [BB]) on growth, carcass traits, meat quality, and bacteriology of growing Japanese quail reared under the cage system. One thousand three hundred sixty Japanese quail day-old chicks were randomly divided into 10 groups (8 replicates each). Birds were fed a basal diet (control, T1) and the basal diet plus 0.05, 0.075, 0.10, and 0.125% BT (T2, T3, T4, and T5, respectively), 0.10% BB (T6), and the same previous doses of BT plus 0.05% BB (T7, T8, T9, and T10, respectively). Results showed a significant (P < 0.001) increase in final BW and weight gain because of probiotic supplementation (except T2 for weight gain). Both feed intake and feed conversion ratio did not differ during the overall experimental period (1–42 D of age) except feed intake that was reduced in T2 and increased in T5 and T9 groups. All carcass traits studied were significantly (P < 0.01) affected by probiotics, and the combination between BT and BB in group T8 increased all studied parameters as compared with the other treatment groups. The quail meat color of redness a∗ and L∗ values, thiobarbituric content, cooking loss, proteolysis, and total coliform were decreased (P < 0.001) by probiotic treatment. In general, supplementing BT, BB, or their combination to the basal diet delayed the proliferation of pathogenic bacteria in the diet and intestine. Using BT and BB as feed supplements enhanced growth performance and meat quality of quails as well as diminished pathogenic bacteria proliferation in their diet and intestine. As per our results, we can recommend the application of T5 and T8 to T10 levels for the best performance, carcass traits, and meat quality of growing quails.

Plants: A natural solution to enhance raw milk cheese preservation?

Plants have been traditionnally used for centuries in cheese manufacturing, either for their aromatic properties or as technological auxiliaries (e.g. milk-clotting enzyme preparations, cheese wrappers). Some of these plants are known to have antimicrobial and/or antioxidant properties and could also act as natural preservatives for raw milk and derived dairy products. This review examined the traditional uses of plants in dairy processing, and then focuses on known antimicrobial and antioxidant properties of their extracts (e.g. maceration, decoction, essential oil). Known effects of theses plants on technological flora (starter cultures and microorganisms implicated in cheese ripening) were also summarized, and the potential for plant extracts used in combination with hurdle technologies was explored. Then, legal restriction and bioactivity variations from a culture media to a food matrix was reviewed: non-toxic bioactive molecules found in plants, extract preparation modes suitable with foodgrade processing restrictions, the role of the food matrix as a hindrance to the efficiency of bioactive compounds, and a review of food legislation. Finally, some commercial plant extracts for milk preservation were discussed.

Influences of stocking density and dietary probiotic supplementation on growing Japanese quail performance

This study investigated the effects of stocking density and dietary supplementation of probiotic (Lactobacillus) on growth, traits of carcass, lymphoid organs and intestinal microbial count of Japanese quail. Quail chicks (one week old) were randomly allotted to 6 groups in a 2×3 factorial experiment included 2 levels of stocking density (100, and 75 cm2/bird) and 3 levels of probiotic (0.00, 0.02 and 0.04 g/kg diet). Quail reared at 100 cm2/ bird showed significantly the highest body weight and daily gain. Quail reared at 75 cm2/ bird had significantly the lower average of feed consumption and the best ratio of feed conversion. Increasing level of probiotic up to 0.04 g/kg led to a significant decrease in dressing percentage by about 2.7 % compared to the control. Interaction effect was insignificant on carcass traits studied except for liver percentage which was significantly higher for birds fed diet supplemented with probiotic at 0.04 g/kg of diet and reared at 100 cm2/bird. Rearing quail at 100 cm2/bird stocking density significantly increased bursa weight. Birds fed diet supplemented with probiotic at 0.02 g/kg of diet and reared at 100 cm2/bird showed significantly the highest (p = 0.043) spleen weight when compared with the other groups. In conclusion, the low (100 cm2/bird) stocking density was sufficient to give better performance of Japanese quail than the other group. Probiotic supplementation diminished the stressful effect of crowding on growing Japanese quail.

Inactivation of Listeria monocytogenes in ready-to-eat smoked turkey meat by combination with packaging atmosphere, oregano essential oil and cold temperature

The effects of packaging atmosphere, storage temperature and oregano essential oil (EO) on growth of Listeria monocytogenes on ready-to-eat smoked turkey were studied. Smoked turkey slices were inoculated with a strain of Listeria monocytogenes Scott A (5.95, 5.28 and 5.26 log CFU/g) then vacuum packaged (VP), modified atmosphere packaging (MAP: 40% CO2 and 60% N2) and MAP with oregano essential oil (MAPEO), respectively. The treated slices were then stored at 0, 5, 10 and 15 °C for 179.88 days and the L. monocytogenes Scott A's growth and microbial shelf life were monitored. The combination of MAP or MAPEO and storage temperature did not allow growth of L. monocytogenes higher than log 1 CFU/g during all storage periods. While in VP temperature combinations, the multiplication of bacteria were ≥ 1 log CFU/g. In VP, MAP and MAPEO smoked turkey, the growth of L. monocytogenes increased regardless of storage temperature. In MAPEO samples the inoculum in the product was suppressed by ca. 5 log CFU/g at 0, 10 and 15 °C at 180, 117 and 81 days of storage, respectively. The inhibition of L. monocytogenes in ready-to-eat smoked turkey by the combinations of MAP and MAPEO was enhanced by storage at 0 or 5 °C. The MAPEO system can be used effectively to control growth of pathogen in processed food when maintaining fixed temperature measures is difficult.

Effects of clove (Syzygium aromaticum) oil on quail growth, carcass traits, blood components, meat quality, and intestinal microbiota

To provide a safe growth promoter, the present study has investigated the effects of different levels of cold-pressed clove oil (CCPO) on growth performance, carcass traits, blood biochemistry, and intestinal microbial population of growing Japanese quails. A total of 300 quails (1-wk old) were randomly divided into 3 treatment groups: control basal diet, basal diet +0.75 mL oil/kg diet, and basal diet +1.5 mL oil/kg diet. Quails fed with 1.5 mL clove oil/kg diet showed a 3.43% improvement in live body weight vs. control group. Similar trend was observed for daily body weight gain. Feed intake gradually increased (P < 0.01) with an increase in clove oil level. The best feed conversion rate was reported for the control group, followed by the group treated with 1.5 mL CCPO/kg diet during the whole period (1 to 6 wk of age). Total globulin differed significantly in 1.5 mL CCPO/kg diet group. Antioxidant enzyme activities, lipid profile, and reduced glutathione concentrations significantly improved in a dose-dependent manner. Blood urea nitrogen, creatinine, malondialdehyde, 8-hydroxy-2΄-deoxyguanosine, and protein carbonyl levels significantly decreased in quails supplemented with 1.5 mL CCPO/kg diet vs. control group. Serum levels of insulin-like growth factor-1, insulin, growth hormone, and thyroxine significantly increased in quails supplemented with 1.5 mL CCPO/kg diet vs. control group. The intestinal bacterial population, coliforms, Escherichia coli, and Salmonella spp. in the ileal content were lower (P < 0.05) in groups treated with oil (1.5 mL/kg) vs. control group. Thus, dietary supplementation with antimicrobial CCPO (1.5 mL/kg diet) could enhance growth performance, improve health status, and reduce intestinal pathogens in Japanese quails.

Improving growth performance and health status of meat-type quail by supplementing the diet with black cumin cold-pressed oil as a natural alternative for antibiotics

Using antibiotics in poultry diets as growth promoters was reported to have harmful effects on consumers, so the current study was done to monitor the impact of dietary supplementation of antimicrobial black cumin oil (BCO) on carcass traits, growth performance, biochemical components, and ileal microbial populations of growing Japanese quails. Three hundred growing Japanese quails were used with three different treatments (0, 0.50, and 1.0 g BCO/g diet). Birds fed diet supplemented with 0.5 g BCO/kg diet showed significant increase in body weight comparing with the control and other treatment group. The daily feed intake and feed conversion ratio were significantly increased side by side with increasing BCO level in the diet. The majority of carcass characteristics were maximized by supplementing the quail diet with 0.5 g BCO/kg. Moreover, liver functions, anti-oxidative capacity, lipid profile and anabolic hormones showed significant improvement in BCO-treated diets in a dose-dependent manner. The BCO showed highest antibacterial effect against Escherichia coli and Salmonella enterica. The ileal bacterial populations, i.e., total bacterial count (TBC), coliform, Salmonella species, and Escherichia coli were decreased in birds supplemented with BCO 0.5 and 1.0 BCO g/kg compared with the control diet. Based on the aforementioned results, conclusion could be drawn that supplementing quail with BCO in their diet could improve productive performance traits and enhance health aspect of the birds.

Improving productive performance and mitigating harmful emissions from laying hen excreta via feeding on graded levels of corn DDGS with or without Bacillus subtilis probiotic

An experiment that included some inclusions of corn distillers dried grains with solubles (DDGS) with or without supplementation of probiotic bacteria to Hi-sex Brown laying hen diets was conducted to evaluate the impacts on performance, egg quality, blood metabolites and nitrogen and phosphorus excretion in the manure. A total of 216 twenty-two-week-old Hi-sex Brown laying hens were randomly divided into eight treatment groups in a factorial design (4 × 2) experiment, which included four levels of DDGS (0, 50, 100 and 150 g/kg diet) plus two levels of Bacillus subtilis probiotic (0 or 1000 mg/kg diet, with a concentration of 1.5 × 108 CFU/g of dried product). The experimental period extended from 22 to 34 weeks of age. The results showed that linear increase in DDGS level up to 150 g/kg improved (p ≤ 0.01) the values of feed consumption, egg shape index and yolk colour compared to the control and other treatment groups. Inclusion of dietary DDGS up to 150 g/kg in layer diets led to a significant decrease in egg mass and a significant increase in Haugh unit score compared to other groups. In the bacillus group, the values of feed conversion, egg weight and egg mass enhanced by 6.45, 3.27 and 7.60% respectively compared with the control diet. Total protein, albumin, triglycerides, cholesterol, calcium and ammonia in serum were significantly (p ≤ 0.01) influenced by DDGS inclusion. The excreted nitrogen decreased by 8.62 and 4.31% in hens fed 50 or 100 g/kg of DDGS respectively, while excreted phosphorous decreased by 3.33, 7.22 and 10.56% in hens fed 50, 100 or 150 g/kg of DDGS respectively as compared to the control group. It could be concluded that increasing DDGS inclusion level in the diet up to 10% and the supplementation of probiotic bacteria improved the productive performance of laying hens and mitigated the harmful emissions from chicken manure; this means better production within environmentally friendly conditions.

Impeding Bacillus spore germination in vitro and in milk by soy glycinin during long cold storage

This paper presents a study of the magnitude and mechanism of impeding the emergent spore germination of Bacillus subtilis (non-hemolytic strain) and Bacillus licheniformis (hemolytic strain) under the action of soybean glycinin and its basic subunit (BS). Incubating B. licheniformis spores with 100 μg/ml of glycinin or BS at 35°C for 24 h totally prevented the hemolytic activity associated with the emergent vegetative cells on blood agar during 3-5 days of incubation at 35°C in contrast to the control. Glycinin and BS (100 μg/ml) also resulted in the leakage of 70 and 73% of the initially germinating spore contents of A260 absorbing materials of the two bacterial species after 2 h of incubation at 35°C, respectively. Increasing the concentration of glycinin and BS up to 400 μg/ml increased the germinating spore leakage to 83 and 88%, respectively. Spore germination in Muller Hinton Broth containing glycinin and BS (100 μg/ml) was practically nil after 4 days of incubation at 35°C. Supplementing milk preheated at 80°C/5 min with both glycinin and BS kept the final vegetative cell counts down to about 30 and 20% of the corresponding control, respectively, after 50 days of storage at 4°C. Both light, and transmission electron, microscopy images revealed significant morphological and structural distorting changes in BS-treated spores of B. licheniformis.

Bioactive proteins against pathogenic and spoilage bacteria

Background: It is likely that both human nutrition and the nutrition of livestock are benefited by the presence of bioactive proteins within their respective diet regimes. Bioactive proteins have been defined as specific protein fragments that positively impact bodily functions or conditions and may, ultimately, influence overall human health. The ingestion of bioactive proteins may have an effect on the major body systems—namely, the cardiovascular, digestive, immune and nervous systems. According to their functional properties, bioactive proteins may be classified as antimicrobial, antithrombotic, antihypertensive, opioid, immune-modulatory, mineral binding and anti-oxidative. There are many examples of biologically active food proteins and active peptides that can be obtained from various food protein sources. They have a physiological significance beyond the pure nutritional requirements; in other wordsthey have the acquisition of nitrogen for normal growth and maintenance.Objective: This study aims to specify and characterize the extent and mode of action of bioactive proteins in their native form, (glycinin, glycinin basic sub-unit and β-conglycinin) against specific main pathogens (Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica serovar Enteritidis). We will be using standard media while identifying the main constituents responsible for this action.Methods: Glycinin, basic sub-unit and β-conglycinin were isolated from soybean protein and tested for their antimicrobial action against pathogenic and spoilage bacteria, They were thencompared to the properties of penicillin. Methylated soybean protein and also methylated chickpea protein (MSP and MCP), with isoelectric points around pI 8, were prepared by esterifying. 83 % of their free carboxyl groups and their interactions with Gram positive and Gram negative bacteria were examined. Results: The three divisions of cationic proteins exhibited antibacterial activities equivalent to or higher than the activity of penicillin, with the basic sub-unit exhibiting the highest activity, Functional Foods in Health and Disease 2014; 4(10):451-462 Page 452 of 462 followed by glycinin.; β-conglycinin exhibited the lowest level of activity with a MIC of 50, 100 and 1000 μg/mL, respectively. The IC50% values of the basic subunit, glycinin and β-conglycinin, against Listeria monocytogenes, were 15, 16 and 695 μg/mL; against Bacillus subtilis the values were 17, 20, and 612 μg/mL; and against Salmonella Enteritidis the values were 18, 21 and 526 μg/mL, respectively. Transmission electron microscopy images of L. monocytogenes and S. Enteritidis exhibited an increase in cell size and a separation of the cell wall from the cell membrane when treated with glycinin or basic sub-unit. The scanning electron microscopy of B. subtilis indicated signs of an irregular, wrinkled outer surface as well as the fragmentation, adhesion, and aggregation of damaged cells or cellular debris when treated with glycinin or the basic subunits; however not with penicillin. The proliferation of L. monocytogenes, S. Enteritidis and Escherichia coli O157:H7-when artificially inoculated in raw milk ,stored at 4 or 25 °C) was significantly (P<0·05) reduced by the glycinin sub-unit and nisin (0·5% w/v); but they were only slightly reduced by β-conglycinin and moderately reduced by lysozyme. The two substances (MSP and MCP) exhibited a concentration-dependent inhibitory action against two of the studied bacteria with a minimum inhibitory concentration of approximately 100 µg/mL. The supplementation of raw milk with esterified legume proteins (MSP and MCP) has significantly (p < 0.05) reduced the levels of TBC, PBC and PSC in raw milk stored at a temperature of 4 °C. This potentially will delaythe onset of spoilage of by four days.Conclusion: Both glycinin and the basic sub-unit have a more swift antimicrobial action than that of penicillin. Basic sub-units exhibited the highest efficiency at killing bacterial cells, followed by glycinin, penicillin and β-conglycinin-with the lowest effect; while the bacteria most susceptible to the antimicrobial agents were shown to be L. monocytogenes, followed by B. Subtilis and S. Enteritidis- with the lowest susceptibility. The antibacterial action of glycinin was similar to the effects exerted by nisin, and was much more effective than lysozyme. The modified legume proteins have general antibacterial properties against both spoilage and pathogenic bacteria in raw milk preserved under refrigeration or at room temperature.Key Words: bioactive proteins, pathogenic and spoilage bacteria

Soft cheese supplemented with black cumin oil: Impact on food borne pathogens and quality during storage

Black cumin seed oil (BCSO) was tested for its inhibitory effect against some pathogenic bacteria (Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Listeria monocytogenes Scott A and Salmonella enteritidis PT4) in Domiati cheese during cold storage. Physical, chemical and sensorial changes in cheese during storage were recorded. Pasteurized milk was inoculated before renneting with a mixed culture of bacteria at ca. 4 log CFU mL(-1). In vitro and in situ supplementation with BCSO showed antimicrobial impact on the growth of S. aureus, E. coli, L. monocytogenes and S. enteritidis inoculated into media and cheese samples. Supplementing of cheese with BCSO (0.1% or 0.2%, w/w) significantly reduced the counts of the inoculated pathogens by ca. 1.3 log and 1.5 log CFU g(-1) after 21 days of storage. In addition, BCSO controlled the development of titratable acidity, limited the changes in ripening indices, flavor components and kept considerable physicochemical and sensorial properties of cheese.

In vitro and in situ antimicrobial action and mechanism of glycinin and its basic subunit

Glycinin, basic subunit and β-conglycinin were isolated from soybean protein isolate and tested for their antimicrobial action against pathogenic and spoilage bacteria as compared to penicillin. The three fractions exhibited antibacterial activities equivalent to or higher than penicillin in the next order; basic subunit>glycinin>β-conglycinin with MIC of 50, 100 and 1000 μg/mL, respectively. The IC(50%) values of the basic subunit, glycinin and β-conglycinin against Listeria\monocytogenes were 15, 16 and 695 μg/mL, against Bacillussubtilis were 17, 20, and 612 μg/mL, and against S. Enteritidis were 18, 21 and 526 μg/mL, respectively. Transmission electron microscopy images of L. monocytogenes and S. Enteritidis exhibited bigger sizes and separation of cell wall from cell membrane when treated with glycinin or basic subunit. Scanning electron microscopy of B. subtilis indicated signs of irregular wrinkled outer surface, fragmentation, adhesion and aggregation of damaged cells or cellular debris when treated with glycinin or the basic subunits but not with penicillin. All tested substances particularly the basic subunit showed increased concentration-dependent cell permeation assessed by crystal violet uptake. The antimicrobial action of glycinin and basic subunit was swifter than that of penicillin. The cell killing efficiency was in the following descending order; basic subunit>glycinin>penicillin>β-conglycinin and the susceptibility of the bacteria to the antimicrobial agents was in the next order: L. monocytogenes>B. Subtilis>S. Enteritidis. Adding glycinin and the basic subunit to pasteurized milk inoculated with the three bacteria; L. monocytogenes, B. Subtilis and S. Enteritidis (ca. 5 log CFU/mL) could inhibit their propagation after 16-20 days storage at 4 °C by 2.42-2.98, 4.25-4.77 and 2.57-3.01 log and by 3.22-3.78, 5.65-6.27 and 3.35-3.72 log CFU/mL, respectively.