Tajalli Keshavarz

Learn More
The cell-to-cell communication of microorganisms is known to be via exertion of certain chemical compounds (signal molecules) and is referred to as quorum sensing (QS). QS phenomenon is widespread in microbial communities. Several Gram-positive and Gram-negative bacteria and fungi use lactone-containing compounds (e.g. acyl-homoserine lactones (AHLs),(More)
Aspergillus terreus is an industrially important filamentous fungus producing a wide spectrum of secondary metabolites, including lovastatin and itaconic acid. It also produces butyrolactone I which has shown potential as an antitumour agent. Additionally, butyrolactone I has been implicated to have a regulating role in the secondary metabolism and(More)
The objective is this study is to simulate a fixed-bed bioreactor using two different arrangements, the first is the modeling of N-reactors in series perfectly blended and then developing a model of a tubular reactor, and comparing the results of both and choose which one is the most appropriate model for optimization, in addition to corroborate the(More)
Increased demand for biodiesel leads to an abundant amount of glycerin in the market. The value of the glycerin has much to offer in reducing the cost of biodiesel production and minimize environmental problems caused by the producers of this biofuel. Strains of the yeast Yarrowia lipolytica has the ability to grow in culture media containing glycerin(More)
Poly(3-hydroxybutyrate), P(3HB), produced from Bacillus cereus SPV using a simple glucose feeding strategy was used to fabricate P(3HB) microspheres using a solid-in-oil-water (s/o/w) technique. For this study, several parameters such as polymer concentration, surfactant and stirring rates were varied in order to determine their effect on microsphere(More)
Filamentous fungi of the Ascomycota phylum are known to contain a family of conserved conidiation regulating proteins with distinctive velvet domains. In Aspergilli, this velvet family includes four proteins, VeA, VelB, VelC and VosA, and is involved in conidiation and secondary metabolism along with a global regulator LaeA. In A. terreus, the(More)
Quorum sensing molecules (QSMs) are involved in the regulation of complicated processes helping bacterial populations respond to changes in their cell-density. Although the QS gene cluster (comQXPA) has been identified in the genome sequence of some bacilli, the QS system B. licheniformis has not been investigated in detail, and its QSM (ComX pheromone) has(More)
In recent years there has been a growing interest for the development of tubular scaffolds employed to assist the replacement of small blood vessels. Materials designed for this purpose need to be biodegradable, have good mechanical properties and improve cell adhesion, proliferation and differentiation. To obtain biomaterials with these properties,(More)
Microbes monitor their population density through a mechanism termed quorum sensing. It is believed that quorum-sensing molecules diffuse from the microbial cells and circulate in the surrounding environment as a function of cell density. When these molecules reach a threshold concentration, the gene expression of the entire population is altered in a(More)
The homopolymer poly(3-hydroxyoctanoate), P(3HO) produced from Pseudomonas mendocina using octanoate as carbon feed was studied as a potential biomaterial for soft tissue engineering i.e. as cardiac patch and as matrices for skin tissue engineering. The polymer was fabricated into neat solvent cast films of 5 and 10 wt %. Microstructural studies revealed(More)
  • 1