Viability of probiotic bacteria and some chemical and sensory characteristics in cornelian cherry juice during cold storage

Background: Increased popularity of vegetarianism, lactose intolerance, and the high cholesterol content in dairy products, are all factors that have recently increased the demand for nondairy probiotic products. The objective of this study is to evaluate the effect of refrigeration on the viability of probiotics and asses some of the chemical and sensory characteristics in cornelian cherry juice. Results: The Iranian native probiotic strain (L. casei T4) showed greater viability compared to industrial types (viable count of 8.67 log cfu/mL versus <6.0 log cfu/mL at d 28). However, this most tolerant Iranian strain, could not withstand the conditions of 'Natural juice' at pH 2.6 for more than 7 d. Following a pH adjusted treatment (to pH ~3.5), the viability of the strain was improved to 28 d with some evidence of increased growth of the probiotic. However, the level of antioxidant activity, anthocyanin and phenolic compounds, revealed a slight decrease during cold storage. The changes in the chemical profile of the sample containing L. casei T4 indicated fermentation activity during cold storage. Sensory evaluation results showed significant differences between samples containing L. casei TD4 and other samples in taste, odor and overall acceptance in a complimentary way. Conclusion: The results showed that low pH and presence of inhibitor phenolic compounds of cornelian cherry juice have negative effect on viability of probiotics, especially industrial strains during refrigerated storage.

Comportamento de cepas distintas de Lactobacillus acidophilus em queijo petit-suisse

O objetivo do presente trabalho foi avaliar as características de físico-químicas e microbiológicas de queijo petit-suisse processado com a adição de duas cepas de Lactobacillus acidophilus: LA-14 (potencialmente probiótica) e La-5 (comprovadamente probiótica), utilizando Streptococcus thermophilus TA040 como cultura starter. Três queijos petit-suisse foram preparados: Q1 (controle:TA040), Q2 (TA040 + LA-14) e Q3 (TA040 +La-5). Foram realizadas análises microbiológicas (determinação das populações dos microrganismos La-5, La-14 e TA040) e físico-químicas (umidade e pH) após 1, 7, 14, 21 e 28 dias de armazenamento dos produtos a 4±1°C. As populações de L. acidophilus oscilaram entre 7,46 e 7,62 log UFC g -1 para La-5 e entre 6,39 e 6,83 log UFC g -1 para LA-14, evidenciando que a sobrevivência de L. acidophilus no produto depende de características particulares da cepa. Populações superiores da cultura starter foram observadas para Q2 (9,58 - 9,68 log UFC g -1 ) e Q3 (9,42 - 9,79 log UFC g -1 ), quando comparadas a Q1 (9,11 - 9,23 log UFC g -1 ), sugerindo sinergismo entre L. acidophilus e o starter. A umidade e o pH permaneceram estáveis e não diferiram entre os queijos após o 1º dia de armazenamento (p>0,05). As características peculiares das cepas de L. acidophilus determinaram os comportamentos distintos observados nos queijos petitsuisse, sendo possível detectar a melhor adaptação da cepa La-5 ao produto, o que resultou em populações significativamente superiores quando comparada a LA-14.

Particular behavior of different Lactobacillus acidophilus strains in petit-suisse cheese. The objective of this study was to evaluate the physico-chemical andmicrobiological characteristics of petit-suisse cheeses manufactured with the addition of two Lactobacillus acidophilus strains: LA-14 (potentially probiotic) and La-5 (probiotic culture), using Streptococcus thermophilus TA040 as starter culture. Three cheese-making trials were prepared: Q1 (control: with TA040), Q2 (with TA040 + LA-14), and Q3 (with TA040 + La-5). Parameters analyzed included microbial counts of probiotic, potentially probiotic and starter microorganisms, and physico-chemical parameters (pH and moisture) after 1, 7, 14, 21, and 28 days of storage of the product at 4±1°C. Viable counts of L. acidophilus remained between 7.46 and 7.62 log CFU g -1 for La-5, and between 6.39 and 6.83 log CFU g -1 for LA-14. As for the starter, higher populations were observed for Q2 (9.58 - 9.68 log CFU g -1 ) and Q3 (9.42 - 9.79 log CFU g -1 ), when compared to Q1, which suggests synergism between L. acidophilus and the starter culture. Moisture and pH values remained stable for cheeses Q1, Q2, and Q3, and no significant differences were detected between cheeses after the first day of storage (p>0.05). Particular features of both L. acidophilus strains determined different behavior in petit-suisse cheese, and the better adaptation of the La-5 to the product environment was perceptible, since higher populations were observed when compared to LA-14.

Avaliação do desempenho de frangos de corte alimentados com rações contendo probiótico e diferentes níveis de nucleotídeos / Performance evaluation of broilers fed diets containing probiotic and different nucleotides levels

objetivo deste trabalho foi avaliar o desempenho de frangos de corte alimentados com ração contendo um probiótico comercial e diferentes níveis de nucleotídeos. Foram utilizados 1050 pintos de 01 dia, machos da linhagem Ross 308 totalizando trinta e cinco aves por boxe, em um delineamento inteiramente casualizado com cinco repetições por tratamento. As aves foram criadas até 42 dias de idade, e receberam as rações experimentais a base de milho e farelo de soja contendo 6 níveis de nucleotídeos (0; 100; 200; 300; 400 e 500 gramas por tonelada de ração). Os nucleotídeos foram utilizados na fase inicial (1 a 21 dias) e fase de crescimento (22 a 35 dias). Durante a fase final (36 a 42 dias) os nucleotídeos foram removidos da ração . Houve melhora linear no desempenho dos frangos no período de 1 a 21 dias, indicando que, quanto maior o nível de nucleotídeos na dieta, maior o peso corporal das aves. A conversão alimentar também melhorou linearmente nesse período à medida que aumentou o nível de nucleotídeos na ração. O peso no período de 35 dias, também teve um comportamento linear, semelhante ao período de 1 a 21 dias, indicando que, o nível de nucleotídeos na ração melhorou o desempenho. A concentração plasmática de acido úrico demonstrou efeito quadrático no período de 1 a 21 dias, indicando 231,59 gramas de nucleotídeos por tonelada de ração, como o melhor, em níveis mínimos de ácido úrico, por outro lado, no período de 35 dias de idade, estimou-se o nível de 208,99 g de nucleotídeos por tonelada de ração; como o melhor em níveis mínimos de ácido úrico no sangue. No período final (35 a 42 dias) e período total (1 a 42 dias de idade) não foi possível o observar efeito dos contrastes testados neste trabalho.

The objective of this study was to evaluate the performance of broilers fed diets containing a commercial probiotic and different levels of nucleotides. One thousand and fifty chicks 1-d male were reared in a randomized experimental design with five replications of each treatment, distributed in 30 experimental boxes with 35 birds each. The diets contained corn and soybean meal with six different nucleotídes levels (0; 100; 200; 300; 400 and 500 grams for ton of ration), and the different nucleotides levels were used in the initial phase (1 to 21 days of age) and growth phase (22 to 35 days of age). During the final phase (36 to 42 days) nucleotides were removed from the feed. There was improvement on broilers performance in the period from 1 to 21 days of age, demonstrating proportionality between nucleotides level in the diet of broilers and body weight of the birds. Feed conversion at 21 days of age was directly proportional to nucleotides level in the diet. Body weight at 35 days of age, also had a linear behavior, similar to the period from 1 to 21 days, indicating that the nucleotides level in the feed improved the performance. Plasma uric acid concentration demonstrated quadratic effect at 21 days of age, showing that 231,59 grams of nucleotides for ton of feed had the minimum level of plasma uric acid concentration. At 35 days of age, concentration of 208,99 g of nucleotides for ton of feed had the minimum level of plasma uric acid concentration. No effects were observed in the final period (35 to 42 days of age) and total period (1 to 42 days of age) it was not demonstrated effect of the contrasts tested in this study.

Assessing the adhesion of putative indigenous probiotic lactobacilli to human colonic epithelial cells.

Background & objectives: Adherence of bacteria to epithelial cells and mucosal surfaces is a key criterion for selection of probiotic. We assessed the adhesion property of selected indigenous probiotic Lactobacillus strains based on their hydrophobicity and ability to adhere to human epithelial cells. Methods: Five human faecal Lactobacillus isolates, one from buffalo milk and one from cheese were assessed for hydrophobicity following the microbial adhesion to hydrocarbons (MATH) method and colonization potentials based on their adherence to Caco2 and HT-29 colonic adenocarcinomal human intestinal epithelial cell lines. Lactobacillus strains that adhered to Caco2 and HT-29 cell lines were quantified by plating after trypsinization and simultaneously the adhered bacteria were also examined microscopically after staining with Geimsa stain and counted in different fields. Results: Among the tested faecal isolates, L. plantarum Lp91 showed maximum percentage hydrophobicity (35.73±0.40 for n-hexadecane and 34.26±0.63 for toluene) closely followed by L. plantarum Lp9 (35.53±0.29 for n-hexadecane and 33.00±0.57 for toluene). Based on direct adhesion to epithelial cells, L. plantarum Lp91 was the most adhesive strain to HT-29 and Caco2 cell lines with per cent adhesion values of 12.8 ± 1.56 and 10.2 ± 1.09, respectively. L. delbrukeii CH4, was the least adhesive with corresponding figures of 2.5 ± 0.37 and 2.6 ± 0.20 per cent on HT-29 and Caco2 cell lines. Adhesion of the six isolated Lactobacillus strain to HT-29 cell and Caco2 lines as recorded under microscope varied between 131.0 ± 13.9 (Lp75) to 342.7 ± 50.52 (Lp91) and 44.7 ± 9.29 (CH4) to 315.7± 35.4 (Lp91), respectively. Interpretation & conclusions: Two Indigenous probiotic Lactobacillus strains (Lp9, Lp91) demonstrated their ability to adhere to epithelial cell and exhibited strong hydrophobicity under in vitro conditions, and thus could have better prospects to colonize the gut with extended transit.

Characterization of the antiyeast compound and probiotic properties of a starter lactobacillus plantarum DW3 for possible use in fermented plant beverages

Lactobacillus plantarum DW3 produced antifungal compounds that inhibited the growth of Rhodotorula mucilaginosa DKA, contaminating yeast in fermented plant beverages (FPBs) and various potential human pathogens. Phenyllactic acid (PLA) identified by gas chromatography- mass spectrometry (GC-MS) was produced at 31 mg/L PLA in MRS medium and 5 mg/ml inhibited growth of the target yeast in vitro by 90 percent. Other inhibitors were also present but not specifically identified. Results of in vitro tests showed that DW3 also had probiotic properties as it survived various human biological barriers resistance to pH 3, bile salts, growth without vitamin B12 and the presence and absence of oxygen. Its inhibitory effect against food borne pathogenic bacteria and spoilage organisms was higher than that found for a commercial strain Lactobacillus casei R. An acute oral toxicity test on ICR mice at a high single dose of either 10(9) and 10(12) cells per mouse for 14 days showed that DW3 had no adverse effect on the general health status and there was no evidence of bacteremia. Mice fed DW3 had a reduced weight gain compared to the control. No significant difference (p > 0.05) was found for the spleen weight index (SWI) among the treatment and control groups whereas there was a significant difference (p < 0.05) for the liver weight ratio (LWR) in a group fed with 10(12) cells per mouse when compared with the control group.

comparative study on the quality of plain and probiotic yoghurt

A total of 40 random samples of plain and probiotic yoghurt [20 of each] were collected from different markets in Kaliobia governorate to evaluate their quality. The sensory characteristic score of probiotic yoghurt [91.69 +/- 7.86] was significantly better than plain one [77.91 +/- 8.16]. The chemical examination indicated that the average values of pH and titratable acidity were 3.63 +/- 0.07 and 0.91 +/- 0.07 for plain yoghurt and 4.29 +/- 0.05 and 0.72 +/- 0.06 for probiotic yoghurt. On the other hand, the bacterial counts in the examined plain and probiotic yoghurt samples were 1.35 x 10[4] +/- 0.22 x 10[4] and 2.12 x 10[3] +/- 0.39 x 10[3]/g for aerobic spore formers count, 4.78 x 10[2] +/- 0.61 x 10[2] and 1.31 x 10[2] +/- 0.17 x 10[2] /g for B.cereus count, 2.01 x 10[3] +/- 0.34 x 10[3] and 4.73 x 10[2] +/- 0.52 x 10[2] /g for staphylococci count and 7.24 x 10[2] +/- 1.83 x 10[2] and 2.58 x 10[2] +/- 0.41 x 10[2] /g for coliform, respectively. Furthermore, B.cereus, B.circulans, B.coagulans, B.licheniformis, B.macerans, B.stearothermophilus and B.subtilis, S.aureus and S.epidermidis as well as micrococci were isolated from both plain and probiotic yoghurt with varying percentages. However, Enteropathogenic Escherichia coli [EEC] were isolated from 5% of plain yoghurt samples and serologically identified as O26: K60 [B6] and O128: K67 [B12]. In contrast, all examined samples of probiotic yoghurt were free from E.E. coli. According to sensory, chemical and bacteriological results, probiotic yoghurt appeared to be better and more safe for human consumption as compared with plain one