The main aim of the present study was the investigation of the viability of two probiotics bacteria of Lactobacillus acidophilus and Lactobacillus plantarum in different environments including simulated gastrointestinal and circumstances namely yogurt. For coating of strains, the double-coating technique was used as the first coating was alginate chitosan and second was Eudragit S100 and the results compared with free-coating cells. the number of free L. acidophilus and L. plantarum were 6.4 × 10 7 ± 3.3 × 10 4 and 7.5 × 10 7 ± 3.5 × 10, respectively, and after 32 days in the last measurement, a sharp decrease in the numbers was observed as they reached to 4.6 × 10 4 ± 0.9 × 10 2 and 1.5 × 10 2 ± 7.9 × 10 1 , respectively. In double-coated condition more number of strains survived as L.

Today, the role of nanotechnology in human life is undeniable as a broad range of industries, particularly food and medicine sectors, have been dramatically influenced. Nanomaterials can contribute to food safety by forming new nano-sized ingredients with modified physicochemical characteristics. Nanotechnologies can inhibit the growth of food spoilage microorganisms by recruiting novel and unique agents that are involved in removal of microbes from foods or prevent adhesion of microbial cells to food surfaces. Hence, nanotechnology could be considered as a high-potential tool in food packaging, safety, and preservation. Moreover, the prevention of biofilm formation by disturbing the attachment of bacteria to the food surface is another useful nanotechnological approach. Recently, nanoparticle-based biosensors have been designed and developed to detect the food-borne pathogens and hazardous substances through complicated mechanisms. During the past half-century, many methods such as freeze-drying and spray drying have been employed for increasing the viability in food industries; however, the other novel approaches such as encapsulation methods have also been developed. Admittedly, some beneficial bacteria such as probiotics bring diverse benefits for human health if only they are in a sufficient number and viability in the food products and gastrointestinal tract (GI). Encapsulation of these valuable microbial strains by nanoparticles improves the survival of probiotics under harsh conditions such as extreme levels of temperature, pH, and salinity during the processing of food products and within the GIT tract. The survival and effectiveness of encapsulated microorganisms depends on different factors including function of cell wall components in bacteria and type of coating materials. This review aims to broadly explore the potential of different aspects of nanotechnology in food industry, especially for packaging, preservation, safety, and viability.

Background: Nanoparticles in biotechnology studies have played a significant role during the recent years and a wide range of them are being applied in food industries to prolong the microorganisms viability for more effective function in food processing and human gut. Methods: The main purpose of this research was evaluating the viability of two bacteria of Lactobacillus casei and Lactobacillus bulgaricus treated through double-coated beads including alginate Chitosan (First coating), and Eudragit S100 (Second coating) in simulated Gastrointestinal (GI) circumstance and yogurt. Free cells were employed as a control test and the results reflected that microencapsulated strains can survive longer than the normal cells. Results: The number of free cells of L. casei and L. bulgaricus respectively decreased from 6.0×106 and 7.2×106 (In the first day) to 4.1×105 and 5.3×106 (In the day 32) in GI condition. Also, in the same intervals of time, the number of double-coated L. casei and L. bulgaricus decreased respectively from 6.9×108 and 7.1×108 to 4.5×107 and 3.1×107 in simulated condition. Furthermore, the pH rate steadily decreased, however, it was more dramatic in the first week, whereas the trend gradually became more moderate in the last two measurements. Conclusion: Results indicated that microencapsulation increases the bacteria viability. Also, the pattern of pH changes was similar for both strains and revealed that the rates of pH and acidity in both double-coated and normal forms are close to the control test in the final measurement.

The aim of the present study was to investigate technological properties of starter strains from traditional dairy products collected from five villages of Lorestan province in Iran. Thirty five samples were cultured on selective media (MRS broth, Nutrient Broth and YGC and then typical colonies checked for morphological features and eventually eighty two strains selected for further examination. The strains were evaluated for Hydrolysis of casein, starch and citrate, growth at 15 and 45 °C, growth in 4 and 6.5% NaCl, resistance to antibiotics (ampicillin, bacitracin, chloramphenicol, erythromycin, gentamicin, penicillin, novobiocin, nalidixic acid) proteolytic and lipolytic and acidification activities. Sixteen strains chosen according to the difference in cell morphology and were identified using API galleries and ability to metabolize various carbohydrates, which consequently, led to identifying seven Lactobacillus casei , five Lactobacillus plantarum , two Saccharomyces cerevisiae and two Bacillus subtilis. In general, two strains of L. casei AKL2, DDL2, two strains of L. plantarum SYL5, ACL4 and one strain of S. cerevisiae DDy2 was demonstrated the most important technological characterization that suitable for using as starter cultures.

The increasing demand for petroleum products generates needs for innovative and reliable methods for cleaning up crude oil spills. Annually, several oil spills occur around the world, which brings numerous ecological and environmental disasters on the surface of deep seawaters like oceans. Biological and physico-chemical remediation technologies can be efficient in terms of spill cleanup and microorganisms—mainly bacteria—are the main ones responsible for petroleum hydrocarbons (PHCs) degradation such as crude oil. Currently, biodegradation is considered as one of the most sustainable and efficient techniques for the removal of PHCs. However, environmental factors associated with the functioning and performance of microorganisms involved in hydrocarbon-degradation have remained relatively unclear. This has limited our understanding on how to select and inoculate microorganisms within technologies of cleaning and to optimize physico-chemical remediation and degradation methods. This review article presents the latest discoveries in bioremediation techniques such as biostimulation, bioaugmentation, and biosurfactants as well as immobilization strategies for increasing the efficiency. Besides, environmental affecting factors and microbial strains engaged in bioremediation and biodegradation of PHCs in marines are discussed.

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