Volume 1 (2017): Issue 3 (July 2017)

Competitive polyhydroxyalkanoate (PHAs) production requires progress in microbial strain performance, feedstock selection, downstream processing, and more importantly according to the process design with process kinetics of the microbial growth phase and the phase of product formation. The multistage continuous production in a bioreactor cascade was described for the first time in a continuously operated, flexible five-stage bioreactor cascade that mimics the characteristics involved in the engineering process of tubular plug flow reactors. This process was developed and used for Cupriavidus necator-mediated PHA production at high volumetric and specific PHA productivity (up to 2.31 g/(Lh) and 0.105 g/(gh), respectively). Based on the experimental data, formal kinetic and high structured kinetic models were established, accompanied by footprint area analysis of binary imaged cells. As a result of the study, there has been an enhanced understanding of the long-term continuous PHA production under balanced, transient, and nutrient-deficient conditions that was achieved on both the micro and the macro kinetic level. It can also be concluded that there were novel insights into the complex metabolic occurrences that developed during the multistage- continuous production of PHA as a secondary metabolite. This development was essential in paving the way for further process improvement. At the same time, a new method of specific growth rate and specific production rate based on footprint area analysis was established by using the electron microscope.

Lactic acid bacteria are frequently utilized in food industry and they are also recognized as antimicrobial agents due to their capability to produce metabolites such as: organic acids, biosurfactants, bacteriocins, hydrogen peroxide, cyclic dipeptides, exopolysaccharides. The main goal of this paper was to present the results of the research carried out on the strain LCM2 of lactic acid bacteria isolated from brined cucumbers, for production of biosurfactants and to assess its antifungal properties. The emulsification capacity of biosurfactant was measured using kerosene as the hydrophobic substrate. The value of emulsification index E24 was 89.04% showing a high emulsification activity of the biosurfactant. The structural characterization of biosurfactant by TLC revealed its glycolipidic nature. Assay of the ionic charge established the anionic charge of the biosurfactant revealed by the presence of precipitation lines towards the cationic surfactant dodecyl-dimethyl-ammonium chloride. The biosurfactant presented antibiofilm activity with low adherence capacity, structural damages of the hyphal net, conidiophores and delays or lack of sporulation and decreased biomass accumulation in four mycotoxigenic Penicillium and Aspergillus isolates. Results of in vitro assays recommend the biosurfactant produced by the new lactic acid bacteria strain LCM2 for biotechnological purposes, as alternative antifungal agent in food industry.

Honey bee colonies are often infected with Nosema apis and Nosema ceranae which cause adult honey bee disease called nosemosis. All honey bee colony members can be infected with these species. In addition, it is claimed to be the main cause of honey bee winter losses in many countries. Nosema spores are expected to resistant the environmental conditions and their infectivity continues for a long time because of long-term durability of fungal spores. In this study, the viability of Nosema spores were investigated in terms of storage situations under laboratory conditions. Honey bee samples that were collected from apiaries in 2011 were investigated to detect the presence of Nosema species with real-time PCR amplification studies. After determination of Nosema species, each sample was divided in two groups. One of these groups was used to find Nosema spore concentration. Nosema solutions were divided and stored at both -20°C and +4°C. The spore concentration was measured every year in the period 2011-2015. Other group of honey bee samples was also stored at -20°C and every year was used for Nosema spore counting. Furthermore, it was examined the infectivity of Nosema spores with sugar solutions which obtained each sample using cage experiment techniques. According to results, when we compare the solutions annually, there is no change at Nosema spore concentration of the solution in -20°C and honeybee samples in -20°C. But reduction was seen at Nosema spore concentration of the solution in +4°C. Nosema spore infectivity tests revealed that infectivity of Nosema spores has not changed significantly between 2011 and 2015. This is the first time mixed Nosema spores found more infective than one-type spore after prolonged exposure to different conditions.

The effect of magnesium ions from gluconate salt at the level of 100, 150 and 200 mg/100g addition on empirical dough rheological properties from the 550 wheat flour type was studied. Dough rheological properties during mixing (dough development time, dough stability, degree of softening), α amylase activity and gelatinization temperature were analyzed by using a Falling Number and Amylograph. During fermentation were analyzed the maximum height of gaseous production, total CO₂ volume production, volume of the gas retained in the dough at the end of the test and the retention coefficient by using a Rheofermentograph device. By magnesium gluconate (Mg) salt addittion dough become more strength by an increase of stability and a decrease of the degree of softening. With Mg addittion wheat flour dough volumes were affected. Compared to the control sample, the dough volume decreased with the increased level of Mg. From the point of view of the α amylase activity, it decreases with the increase level of Mg whereas the gelatinization temperature increases.

The present research was planned to characterize the aroma composition of Viburnum opulus L. which is one important members of the Caprifoliaceae family. Volatile components of Viburnum opulus L. were extracted by use of the purge and trap technique with dichloromethane and analyzed by gas chromatography-mass spectrometry (GC-MS). The extraction method gave highly representative aromatic extract of the studied sample. A total of 47 aroma compounds were found including acids, alcohols, ketones, volatile phenols, aldehydes, furans, lactones, an ester a terpene and a pyranone. Among all aroma compounds, isovaleric acid was found as the most abundant aroma compound in the fermented GR juice, having a 30% of total aroma concentration. Butanoic acid, 4-methyl catechol and propanoic acid were other aroma compounds found in higher concentrations (18%, 11% and 6% respectively).

Thio-Schiff bases are becoming increasingly widespread in various branches such as the preparation of certain medicines, cosmetic products, and polymer production. In particular, the presence of antibacterial, antifungal, antiviral, antitumor and antimalarial properties of Schiff bases containing sulfur in the structure has made these compounds attractive in different disciplines. In this study, different derivatives of dimeric disulfide-Schiff bases have been synthesized. The antibacterial and antifungal activities of the synthesized these compounds were investigated in vitro against some human pathogens (Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and Candida albicans, C. tropicalis, C. guilliermondii and C. glabrata). Test microorganisms were isolated from the patients appyling to Medical Faculty Hospital of Duzce University were used. Diffusion method was used to determine the antimicrobial activities of the compounds.standard antibacterial (Cefotaxime, Amoxicillin/clavulanicacid) and antifungal (Posaconazole) antibiotics were used as the control group and the results were compared. The result indicated that antimicrobial activity of Disulphide-Schiff Base Derivatives exhibited less activity against bacteria as compared to AMC30 (Amoxicillin/clavulanicacid), but highly effective against bacteria as compared to CTX30 (Cefotaxime). In addition, the compounds exhibited less activity against yeast.

Affordable and practical synthesis methods in drug development have always been very attractive. Herein, microwave assisted synthesis was utilized to prepare piperazine substituted 5-chloro-2(3H)-benzoxazolone derivatives in 5 minutes. Structural characterization of these 5-chloro-2(3H)-benzoxazolone derivatives was achieved by IR, NMR, ESI-MS and elemental analysis. Since these types of compounds have been shown to have anti-inflammatory and analgesic activities there biological activities were also examined. Indomethacin (INDO) and acetylsalicylic acid (ASA) were used as reference. Carrageenan-induced hind paw edema in mice test was used to study anti-inflammatory activity. Compound 1 (100 mg / kg dose) showed the longest anti-inflammatory activity among the title compounds synthesized. For the analgesic activities, both hot-plate and tail-flick tests were employed. Compound 3 was found to have the highest activity in the hot-plate test whereas in the tail-flick test, compounds 1 and 2 showed higher anti-nociceptive activity.

Multiple sclerosis (MS) is an autoimmune disease of the human central nervous system. It is one of the most common neurological disorders around the world and there is still no complete cure for MS. Purification of a terpenoid from Capparis ovata was carried out and its structure was elucidated as stigmast-5,22-dien-3β-ol, myristate (3β,22E-stigmasteryl myristate; SDM) by NMR and mass spectral analyses. No information regarding its any health effect is available in the literature. In the present study, we have described its effects on inflammatory factors such as the expression levels of cytokines, chemokines and adhesion molecules as well as apoptosis/infiltration and myelination in SH-SY5Y cells. The expression levels of proinflammatory or inflammatory cytokines and chemokines such as NF-κB1, CCL5, CXCL9, CXCL10 and HIF1A along with T-cell activating cytokines such as IL-6 and TGFB1 were significantly downregulated with SDM treatment. Moreover, the expression levels of the main myelin proteins such as MBP, MAG and PLP that are essential for healthy myelin architecture were significantly up-regulated. The results presented in this study strongly suggest that the SDM offers a unique possibility to be used with autoimmune diseases, including MS due to its activity on the manipulation of cytokines and the promotion of myelin formation.

Genetic improvement of crop drought tolerance has become an urgent need for increasing agricultural yields and food production, to feed a growing human population in the context of global climate change. To get insights into the most relevant mechanisms underlying drought resistance in beans, we have analysed the responses to water deficit of three Phaseolus vulgaris (common bean) and one P. coccineus (runner bean) cultivars, focusing on the accumulation of specific osmolytes, a conserved response to abiotic stress in plants. Changes in osmolyte levels were correlated with the relative tolerance to water stress of the studied cultivars. Drought tolerance in Phaseolus largely depends on the accumulation of myo-inositol; glycine betaine may also contribute to tolerance in P. coccineus (but not in P. vulgaris). Proline, another common osmolyte, is a reliable marker of the level of stress affecting bean plants, but is not directly involved in tolerance mechanisms, as its drought-dependent accumulation is lowest in the most tolerant cultivar. We suggest that, by measuring the levels of proline and myo-inositol in water-stressed plants, a large number of cultivars could be easily and rapidly screened to select promising candidates to be used in breeding programmes for improving drought tolerance in beans.

Plants have evolved effective defense mechanisms against stress-induced oxidative damages, among which an important role play glutathione S-transferases (GSTs). This huge class of proteins have been reported to increase in a number of crops under temperature and saline stresses. However, different wheat cultivars display specific characteristics of expression. In our study we controlled the transcription of GSTF1 gene at leaves of wheat (Triticum aestivum L.) of local cultivar Dajti, evaluated previously as resistant toward salt and temperature stresses. Three different concentrations of NaCl, 50, 100, 200mM, were applied at plants germinated in Hoagland culture, and total ARN was extracted from leaves collected at 0-3-6-10-24-72 hrs after treatment. Seeds from the same cultivar were germinated in Hoagland culture under heat treatment, keeping controls at 25°C/20°C and the rest under a 35°C /25°C-day/night regime in a growth chamber. Total RNA was extracted after one week, 30, and 45 days following HT. RT-PCRs were performed using primers specific for GSTF1. Concentration of amplicons was evaluated in agarose gels. In conclusion, the transcription of GSTF1 at Dajti cultivar is reduced during the time of exposure on saline conditions, does not depend on salt concentration, and is not affected by prolonged temperature stress.