Microbiological studies on some soft cheeses in Taiz city

This investigation aims to study the effect of different storage temeratures on the microorganisms and keeping quality of local and imported soft cheeses. The samples were taken from different markets in Taiz City, Republic of Yemen. Both local and imported soft cheeses samples were stored at 28, 10 and 4°C. The samples stored at 28°C were used as control samples. Microbiological changes were followed by examination of samples during storage at zero time and weekly [every 7 days] for a period of 60 days until signs of spoilage appeared. The results indicated that cold storage at 10°C reduced the contamination for the Aerobic, Anaerobic, Spore formers, Lactic acid bacteria, Coliform group, Salmonella spp, Staphylococcus spp, Streptococcus spp, Bacillus spp, Clostridium spp, Enterococcl spp, Proteolytic bacteria, Psychrophilic bacteria and Yeast and Moulds counts by the following percentages: 47.63 and 50.10%, 31.66 and 36.50%, 28.32 and 24.84%, 33.33 and 33.89%, 35.44and 33.80%, 36.76 and 37.80%, 42.50 and 42.50%, 37.06 and 34.39%, 33.90 and 34.92%, 34.95 and 38.87%, 38.73 and 39.64%, 57.55 and 50.76%, 33.07 and 30.37% and 45.61 and 47.37% of local and imported soft cheeses respectively as compared with their control samples.. Also the cold storage at 4 °C induced a reduction by the following percentages:52.16 and 53.75%, 33.33 and 39,18%, 38.22 and 34.74%, 39.96 and 49.32%, 38.23 and 42.00%, 41.10 and 42.95%, 45.60 and 50.00%,38.98 and 36.24%, 36.87 and 37.66%, 36.1 and 46.83%, 46.60 and 59.13%, 59.95 and 66.00%, 42.51% and 43.45% and 62.71 and 63.43%for the mentioned microbes and samples, respectively as compared with their control samples. However, the shelf-life were increased by 21and 37 days when using a cold storage at 10 °C and extended by 30 and 60 days when using a cold storage at 4 °C of local and imported soft cheeses, respectively as compared with their control samples. As well as the isolation and classification of [65] bacterial isolates from the above samples, those bacteria identified as [27] of Bacillus spp, and [38] of Lactic 0cand/spp, both species divided into five groups

Prediction of acid lactic-bacteria growth in turkey ham processed by high hydrostatic pressure

High hydrostatic pressure (HHP) has been investigated and industrially applied to extend shelf life of meat-based products. Traditional ham packaged under microaerophilic conditions may sometimes present high lactic acid bacteria population during refrigerated storage, which limits shelf life due to development of unpleasant odor and greenish and sticky appearance. This study aimed at evaluating the shelf life of turkey ham pressurized at 400 MPa for 15 min and stored at 4, 8 and 12 ºC, in comparison to the non pressurized product. The lactic acid bacteria population up to 10(7) CFU/g of product was set as the criteria to determine the limiting shelf life According to such parameter the pressurized sample achieved a commercial viability within 75 days when stored at 4 ºC while the control lasted only 45 days. Predictive microbiology using Gompertz and Baranyi and Roberts models fitted well both for the pressurized and control samples. The results indicated that the high hydrostatic pressure treatment greatly increased the turkey ham commercial viability in comparison to the usual length, by slowing down the growth of microorganisms in the product.

Identification and biological activity of potential probiotic bacterium isolated from the stomach mucus of breast-fed lamb

The lactic acid bacterium E isolated from the stomach mucus of breast-fed lamb was identified by sequencing of 16S rDNA fragment and species-specific PCR as Lactobacillus reuteri. Its potential antimicrobial activity and ability to modulate immune system in vitro and in vivo was determined. The growth inhibition of potential pathogens decreased from Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica ser. Minnesota to Escherichia coli. The lowest inhibition activity was observed in the case of Candida albicans. The ability of L. reuteri E to modulate biological activities of human and mouse mononuclear cells was estimated in vitro and in vivo, respectively. The production of IL-1β by monocytes in vitro was significantly induced by L. reuteri E (relative activity 2.47). The ability to modulate biological activities of mononuclear cells by living L. reuteri E cells in vitro in comparison to disintegrated L. reuteri E cells in vivo differed. For example lysozyme activity in vitro was inhibited while in vivo was stimulated (relative activities 0.30 and 1.83, respectively). The peroxidase activity in vitro was stimulated while in vivo was inhibited (relative activities 1.53 and 0.17, respectively). Obtained results indicate that L. reuteri E is potential candidate to be used in probiotic preparations for animals and/or human.

Identification of lactic acid bacteria associated with traditional cachaça fermentations

During the production of traditional cachaça (alembicïs cachaça), contamination of the fermented must is one of the factors leading to economic losses in the beverage manufacturing industry. The diversity of bacterial populations and the role of these microorganisms during the cachaça production process are still poorly understood in Brazil. In our work, the fermentation process was followed in two distilleries located in the state of Minas Gerais. The objective of this work was to identify the populations of lactic acid bacteria present during cachaça fermentation using physiological and molecular methods. Lactic acid bacteria were isolated in high frequencies during all of the fermentative processes, and Lactobacillus plantarum and L. casei were the most prevalent species. Other lactic acid bacteria were found in minor frequencies, such as L. ferintoshensis, L. fermentum, L. jensenii, L. murinus, Lactococcus lactis, Enterococcus sp. and Weissella confusa. These bacteria could contribute to the increase of volatile acidity levels or to the production of compounds that could influence the taste and aroma of the beverage.

Obtención de ácido láctico por fermentación con Lactobacillus delbrueckii bulgaricus / Obtention of lactic acid for fermentation with Lactobacillus delbruekii bulgaricus

El sustrato compuesto por sacarosa y suero de sangre de res, utilizado para la producción de ácido láctico, a través de Lactobacillus delbrueckii bulgaricus, ofrece al microorganismo los nutrientes necesarios para un buen crecimiento, bajo condiciones óptimas de pH(5,5 - 6,0) y temperatura de 48ºC. La velocidad máxima de crecimiento del microorganismo obtenido bajo estas condiciones es del orden del 0.068/h a un inóculo del 1,0 por ciento y disminuye hasta llegar a valores del orden de 0,024/h con inóculo 2,5 por ciento; lo contrario sucede con su crecimiento en masa celular o biomasa; esta aumenta a medida que se aumenta el porcentaje de inóculo, partiendo de rendimiento del 0,10 por ciento a inóculos del 1,0 por ciento hasta llegar a 0,65 por ciento con inóculo del 2,5 por ciento. La mayor producción que brinda este medio es del orden del 81,25 por ciento para una concentración de sacarosa de 60g/l y un inóculo del 2,5 por ciento; mientras que su mayor productividad fue de 0,57 g/lh a una concentración de sacarosa de 100g/l y un inóculo de 2,5 por ciento

Serum lactate dehydrogenase levels in female genital tumors

The influence of tumor growth on the various pattern of enzyme activity has been intentively studied during the past few decades. The most unremitted efforts were devoted to determine the enzymatic derangement within normal cells which underwent neoplastic activities. This will provide a clue to the problem of early diagnosis, mangement and prognosis of these turmors. the growth of tumor may lead to an increase of the enzyme activities in the serum.Serum LDH level was measured by ultraviolet spectrophotometric method in 20 normal females and in 45 females patients with different benign and malignant genital tumors before and after treatment. These included 11 patients with ovarian malignancies. 11 patients with benign ovarian tumors, 3 patients with endometrial carcinoma, 5 patients with uterine fibromyoma. 5 patients with cancer cervix, 6 patients with cancer vagina and 4 patients with cancer vulva. In normal control group the serum levels ranged between 120 -240 mU/ml. with a mean of 167 +/- 60. Serum LDH was considerably elevated in cases of malignant ovarian tumors [535 +/- 267]. Moreover, there was a drop in serum LDH levels after treatment [232 +/- 103] and the levels were noramlized one week later complete surgical removal. Serum LDH levels were not elevated in cases of benign ovarian tumors [200 +/- 53 before treatment and 119 +/- 52 after treatment] fibromyoma of the uterus [l46 +/- 53], endometrial carcinoma [187 +/- 54 before treatment and 145 +/- 56 after treatment]. carcinoma of the cervix 113 +/- 47], cancer vagina [204 +/- 91] and carcinoma of the vulva [200 +/- 75]. Measurement of serum LDH in this context is potentially valuiable in the diagnosis and management of patients with ovarian carcinoma