Crossing Lilium Orientals of different ploidy creates Fusarium-resistant hybrid

Oriental hybrid lily is of great commercial value, but it is susceptible to Fusarium disease that causes a significant loss to the production. A diploid Oriental hybrid resistant to Fusarium, Cai-74, was diploidized from triploid obtained from the offspring of tetraploid (from ‘Star Fighter’) and diploid (‘Con Amore’, ‘Acapulco’) by screening the hybrids of different cross combinations following inoculating Fusarium oxysporum to the tissue cultured plantlets in a greenhouse. By analyzing saponins content in bulbs of a number of lily genotypes with a known Fusarium resistance, it was found that the mutant Cai-74 had a much higher content of saponin than its parents. Highly resistant wild _L. dauricum_ had the highest level (4.59mg/g), followed by the resistant Cai-74 with 4.01mg/g. The resistant OT cultivars ‘Conca d’or’ and ‘Robina’ had a higher saponins content (3.70 mg/g) and 2.83 mg/g, than the susceptible Oriental lily cultivars ‘Sorbonne’, ‘Siberia’ and ‘Tiber’. The hybrid Cai-74 had a different karyotype compared with the normal Lilium Oriental hybrid cultivars. The results suggested that Cai-74 carries a chromosomal variation correlated to Fusarium resistance. Cai-74 might be used as a genetic resource for breeding of Fusarium resistant cultivars of Oriental hybrid lilies

The effect of frozen storage on the survival of probiotic microorganisms found in traditional and commercial kefir

Kefir is a fermented milk traditionally made from a unique starter culture, which consists of numerous bacteria and yeast species bound together in an exopolysaccharide matrix produced by certain lactic acid bacteria. Many health benefits are associated with traditionally produced kefir; however, bulging and leaking packaging, caused by secondary yeast fermentation during storage, has limited large scale manufacture traditionally produced kefir. Commercial kefir products have been designed to reduce these effects by using a pure starter culture consisting of a mixture of bacteria and yeast species that give a flavor similar to traditional kefir, but some health benefits may be lost in commercial production due to reduced microbial diversity and lack of beneficial exopolysaccharides. In this study, traditional and commercial kefir was frozen to study the effects of frozen storage on the viability of probiotic bacteria over time. The traditional kefir was prepared by inoculating 1 L of pasteurized whole goats milk with approximately 30 g of kefir grains. Commercial kefir was prepared by inoculating 1 L of full fat, pasteurized goat milk with a commercial kefir starter. The milk was allowed to ferment at room temperature (24-28°C) until pH 4.6 was reached. Samples were frozen (-8 to -14°C.) immediately following the completion of fermentation and were thawed and plated for lactobacilli, lactococci and yeasts on day 0, day 7, day 14 and day 30 of frozen storage. Statistical analysis was preformed by statistical analysis software (SAS®) using the variance analysis (ANOVA) f-test, with a confidence interval of 95% (P\u3c0.05). Means were compared by the least significant difference (LSD) test. Lactobacilli, lactococci and yeasts were significantly (P\u3c0.05) reduced in number during frozen storage; however, the traditionally produced kefir was shown to have significantly (P\u3c0.05) higher counts of bacteria and yeast at each sampling. It was concluded that frozen storage and the development of frozen kefir products could eliminate most packaging concerns associated with the large scale manufacture of traditionally produced kefir, resulting in increased production and marketability of this healthful product

Effects and safety of selected antagonistic bacteria against Escherichia coli in leafy green vegetables

We live in a busy world, where the demand of ready-to-eat (RTE) salad products has increased rapidly in a relatively short time. Despite of being an easy and fast way to add more vegetables to the daily diet, RTE salads have a serious underlying risk and the amount of vegetable-derived foodborne disease outbreaks has been increasing. The aim of the present study is to protect plants against contamination with human pathogens by inoculating spinach (Spinacia oleracea) seeds with antagonists, inherent on leafy green vegetables. Experiments were carried on to observe the effects of selected antagonistic bacteria against non-pathogenic Escherichia coli CCUG29300T contamination on live spinach sprouts, and to test the safety by studying the immune response in mice. In addition, bacterial isolates from RTE rocket salad (Eruca sativa) were identified by 16S rRNA gene sequencing. The putative results show that bagged rocket salad contains bacteria from several different families and genera, the most abundant being Pseudomonas, commonly found from leafy green vegetables and Aeromonas that are omnipresent in soil, water and vegetation. Surprising findings were Rheinheimera, Chryseobacterium, and Shewanella that are more commonly associated with a marine environment. Unfortunately, the antagonistic effect of selected bacteria could not be seen in this study, as no statistically significant differences between treated samples and negative control were found (p>0.05). The seed pellet may work as a physical barrier hindering the inoculation, or has antimicrobial effects that increases the death rate of two antagonists. FACS analysis of Peyer’s patches and mesenteric lymph nodes of mice indicate that the tested antagonists may be able to suppress non-pathogenic E. coli induced inflammation in mice. In Peyer’s patches, the percentage of gated CCR9+CD8+CD69+ cells was significantly lower in the groups A (15.9 (6.2–23.2), p=0.037) and E (17.1 (7.7–25.3), p=0.029) compared with the control group K (30.3 (20.8–72.1)). These percentages were on the similar level with the untreated group N (13.7 (10.3–17.6)). The percentage of TLR2+TLR4+ activated macrophages in the antagonist groups varied between E 22.7 (21.7–35.7) and B 28.9 (18.6–39.1). All results were significantly lower compared with the group K 62.7 (57.2 – 67.9). There were no significant differences in water or feed intakes between groups, which indicates that antagonist treatment do not make mice feel sick. This study supports the current knowledge of leafy green vegetables harbouring a very diverse microflora with genera with potential human pathogens. Despite of poor results in antagonistic effect experiment, preliminary results indicate that selected antagonists do not trigger a negative immune response in miceAs we all may know, fruits and vegetables have numerous health-promoting effects as in minerals, vitamins, and fibre. Living in the busy world make us seeking products that do not require too much preparation and that’s why ready-to-eat (RTE) products are getting popular every day. However, RTE salads and salad mixes may have a microscopic surprise that makes our stomachs to feel uneasy or in the worst case, have more severe consequences. This surprise can be Norovirus, enterohemorrhagic Escherichia coli, or Salmonella. These microbes can be found from water or several other foods, but there are no eliminative steps in salad that remove these harmful visitors. For the consumer who wants to eat RTE salads, the best advice is to check that everything looks fresh. Brown or squished salad leaves may seem harmless, but the salad juice is a very powerful nutrient for bacteria and just simply removing the damaged leaves does not change the situation that the bacteria have had a long time to grow inside the bag. But what can science do? Competition is all around us, also in our salad. The main reason for foodborne illnesses is, that the harmful bacteria have found their way to the salad and been successful in the growth competition. It has been found out that several bacteria, commonly present in the leafy green vegetables can reduce the growth of Escherichia coli, because they are natural part of the microflora of leafy green vegetables. These bacteria can be called antagonists - organisms that are able to interfere the normal growth of harmful bacteria. In this study we added these antagonists to spinach sprouts through the leaves and the seeds, hoping to see the promising antagonistic effect as reduced E. coli concentration. Unfortunately, working with living organisms is not always easy. Even though the antagonist effects have been present in previous experiments, they could not be seen this time as the introduction of the antagonists into the plants did not go as planned. Our bodies undergo constant competition as well. Sometimes we get sick as the first defence line fails to eliminate the intruder or it takes too long. Luckily we have also the adaptive immune system, which contains several specialized cells and is ready to activate whenever needed. As we are using the antagonistic bacteria to suppress E. coli, it is important to make sure that these antagonists are not found as harmful intruders by the immune system. Since it is not possible to test these things straight on humans, an animal study was carried out. The mice were pre-treated with antibiotics and harmless E.coli to have equal bacterial composition in their guts. The antagonists were given to the mice in drinking water, and their well-being was monitored daily. In the end, the immune response of mice was studied by observing the levels of activated defensive cells in their organs. The preliminary results indicate that the antagonists do not change the consumption behaviour of mice, or trigger a negative immune response. Several defensive cell levels were lower in the mice who got the antagonists, compared with those who got only E. coli. This may indicate that the antagonist are able to suppress the immune response caused by E. coli. More work is needed to find an optimal way to introduce the antagonist to the plants, and to study the immune response on deeper levels. However, the results of this study indicate that we may have to be able to fight against harmful visitors of our foods by partnering with the antagonist bacteria, and thereby offer everyday consumers safer ready-to-eat salads to enjoy

Evaluation of the energetic cost of bacterial elimination of E. Coli using the electroporation technique in cuvette vessels

In the last two years, the percentage of cases in Peru linked to diarrheal diseases in children has been considerably reduced, demonstrating that even in difficult times health must always be our greatest strength. Of course, fulfilling this desire requires that all Peruvians have access to treated water sources to comply with their personal hygiene duties. However, nearly 3 million Peruvians live without access to drinking water and leave their health to the fate of natural water sources with high probabilities of containing bacteria and viruses. Under this premise, the purpose of this thesis was to show the effectiveness of an alternative water sterilization treatment that could be of great help to these Peruvians in need. A methodology based on the 'electroporation' technique was developed through the application of low and high intensity electric field pulses, seeking to damage the cell membrane of Escherichia coli (E. coli) bacteria and inactivate their growth in contaminated water volumes. The E. coli cell was cultured in the laboratories of the University of Engineering and Technology and diluted in 9 ml of tap water to form a theoretical suspension of 480 CFU/ml of water. To meet the objective, pulses of 1, 5, 6, 10 and 15 kV/cm were applied to the contaminated water through cuvettes (400 μl) and the percentage of bacteria surviving the treatment was documented using the colony counting technique in Petri dishes. Respective measurements of pH, absorbance, and temperature of the water samples, as well as electrical measurements of the cuvettes, were performed moments before and after the application of the pulses. With this it was concluded that 1 kV/cm was sufficient to inactivate between 50-70 % of E. coli colonies when unipolar type pulses are applied in a time range of 20-22 μs. The minimum energy required to meet this result was simulated using MATLAB software and was 0.06092 J. This study did demonstrate that electric field is an effective physical phenomenon capable of sterilizing tap water samples using cuvette containers

A Holistic Approach to Service Survivability

We present SABER (Survivability Architecture: Block, Evade, React), a proposed survivability architecture that blocks, evades and reacts to a variety of attacks by using several security and survivability mechanisms in an automated and coordinated fashion. Contrary to the ad hoc manner in which contemporary survivable systems are built--using isolated, independent security mechanisms such as firewalls, intrusion detection systems and software sandboxes--SABER integrates several different technologies in an attempt to provide a unified framework for responding to the wide range of attacks malicious insiders and outsiders can launch. This coordinated multi-layer approach will be capable of defending against attacks targeted at various levels of the network stack, such as congestion-based DoS attacks, software-based DoS or code-injection attacks, and others. Our fundamental insight is that while multiple lines of defense are useful, most conventional, uncoordinated approaches fail to exploit the full range of available responses to incidents. By coordinating the response, the ability to survive even in the face of successful security breaches increases substantially. We discuss the key components of SABER, how they will be integrated together, and how we can leverage on the promising results of the individual components to improve survivability in a variety of coordinated attack scenarios. SABER is currently in the prototyping stages, with several interesting open research topics

FORMULATION AND EVALUATION OF PROBIOTIC AND PREBIOTIC LOADED PELLETS BY EXTRUSION AND SPHERONIZATION FOR IMPROVED STORAGE VIABILITY

Objective: The present study aims to prepare stains-loaded enteric-coated pellets by extrusion and spheronization technique for acidic environment protection and improve the viability of the strains during storage. Methods: Lactobacillus casei and Lactobacillus plantarum strains are proven to have various therapeutic and prophylactic uses in human beings, but low stability during storage and transit to site of action has limited their action. Pellets were prepared by incorporating probiotic strains D1-D9 (L. casei) and E1-E9 (L. plantarum) by further enteric-coating the pellets, which were evaluated for particle size, loss on drying, friability, micromeritic properties, viability, disintegration, survivability in acidic and bile juices, and stability studies for 90 d respectively. Results: The method employed for preparing the pellets showed good % yields with a particle rage of 1400-850 µm. LoD values were in the range of 3.07±0.30% to 2.13±0.11%; all the prepared pellets showed good flow properties and friability in an acceptable range. SEM images revealed that enteric-coated pellets had smooth and uniformly surfaces. The viability results ranged from 8.78±0.31 to 8.53±0.15 log CFU/g and 8.47±0.15 to 8.85±0.22 log CFU/g for both L. casei and L. plantarum enteric coated pellets, respectively. The Disintegration time for the pellets was<15 min in all the formulations. The enteric-coated probiotic pellets provided adequate protection against the acidic environment. Studies of survivability in simulated gastrointestinal conditions demonstrated that formulations D7 and E7 showed higher viability among the formulations at the end of 3 h. The stability studies showed that the formulations with a higher concentration of Inulin and pectin combination proved better viability of L. casei and L. plantarum strains in the formulation during 90 d of stability study. Conclusion: This study suggested that using extrusion and spheronization techniques can be employed to prepare pellets with prebiotics (Inulin and Pectin) which can be utilized to formulate probiotic dosage forms with improved viability in physiological conditions and real-time storage condition

Harvester Ant \u3ci\u3e(Pogonomyrmex sp.)\u3c/i\u3e Seed Preferences and Distribution in a Suburban Setting

Harvester ants (Pogonomyrmex sp.) are omnivorous ants native to Texas and are the main food source for the threatened Texas Horned Lizard (Phrynosoma cornutum). Little research has been conducted on harvester ants in the Lower Rio Grande Valley (LRGV) and their interactions with their environment. For this purpose, a variety of experiments were conducted to better understand these interactions and preferences. In CHAPTER I, suburban harvester ants were exposed commonly used cover crop seeds in the LRGV and inoculated seeds via seed depots over the course of 24 hours. We found that harvester ants do have preferences for some seeds over others and are impartial to the addition of inoculum. In CHAPTER II, spatial analysis, elevation, impervious surfaces, and soil moisture were analyzed and compared between areas with and without ant colonies. We found that ant colonies were significantly clustered together within this landscape. Within the larger landscape, elevation but not impervious surface was a significant factor in colony placement. Within the subset area soil moisture was not an important predictor. Determining the specific conditions harvester ant colonies choose to reside in could help citizens take proper measures to reduce the likelihood of colony establishment on their property

Approaches for improvement in digestive survival of probiotics, a comparative study

The aim of this study was to compare approaches commonly recommended in the literature for the improvement of the survival of probiotics in the human digestive tract. The survival of two probiotics, L. casei W56 and B. lactis W52, in the presence or absence of prebiotics, maize starch, fermented milk and upon encapsulation in calcium alginate-chitosan were evaluated. While B. lactis W52 was resistant to stomach juice, but sensitive to duodenal juice, L. casei W56 showed an exactly opposite behaviour. Overall the digestive survivability of probiotics was not improved by prebiotics, maize starch or encapsulation. A significant improvement of the overall survivability of B. lactis W52 (but not L. casei W56) during in vitro digestion was noted in milk and fermented milk, possibly due to reduction of the activity of bile against this probiotic. Overall no one method could be recommended universally for the improvement of probiotic survivability. Nevertheless, this research indicated that certain probiotic characteristics, such as susceptibility to bile or acid or ability to utilise matrix components as an energy source could perhaps be used in further research to select the most effective approaches to deliver viable cells into lower parts of the digestive tract

The Phylogenetic Analysis Of Genes Encoding Specific Steps In The Glutathione Pathway Within Industrial Beer Brewing Strains: Saccharomyces Cerevisiae, Saccharomyces Pastorinus, And The Spoilage Microbe Brettanomyces

The Glutathione pathway, (GSH) is an antioxidant system in yeast that increases cell viability and contributes to the production of desirable beer flavors during industrial fermentation. Despite its importance, studies using the GSH pathway: GSH1, GSH2, GLR1, and SOD1 genes, to trace the evolutionary history of beer strains are lacking. As a result, the investigator sought to elucidate the phylogenetic relationships between four commonly used industrial beer strains: California Ale, London Ale, Oktoberfest, and Brettanomyces bruxellensis through single-gene sequencing analysis of the GSH pathway. It was hypothesized that the actions of these GSH genes are unique and potentially upregulated in beer brewing yeasts when compared to non-brewing yeasts strains. In order to assess this theory, GSH pathway genes from the experimental industrial strains, were sequenced in order to demonstrate that brewing yeast exhibit identical GSH pathway sequences as an adaptation to their shared brewing environments. Following genome sequencing and phylogenetic analyses, the investigator found that these strains possessed identical GSH pathways as a result of various physiological adaptations and prolonged use within industrial settings. The investigator’s results highlight the evolutionary significance and functionality of GSH pathway genes and demonstrate the essentialness of antioxidant activity in industrial yeast strains. These results also revealed that important strain related associations can be inferred through an analysis of essential metabolic pathways