బయోప్రాసెసింగ్ & బయోటెక్నిక్స్ జర్నల్

Lactic acid bacteria (LAB) like Lactococcus lactis ssp. lactis are used in food industry as well as for production of bacteriocins and optically pure lactic acid. Fixed-bed processes are highly productive but mathematical description is often complex. The aim of this work was to establish a mathematica model for process design. Biomass formation, lactose consumption and lactate production during start-up of fixed-bed cultures with immobilized L. lactis was investigated experimentally and described by a reaction kinetics model. Appropriate modeling and simulation of fixed-bed processes require biomass data. Therefore, a low-volume multiple fixed-bed reactor system (Multiferm) was used to investigate biomass formation of a L. lactis strain during the start-up phase of fixed-bed cultivation. The generation of data in parallel experiments was fast and easily compared to larger single reactor systems. Biomass data obtained from both fractions, retained and free suspended biomass, was used for modeling and simulation, together with data for lactose and lactate. The underlying Luedeking-Piret-like model structure was developed based on the results from suspension cultivations with the same strain. The fixed-bed system was described as perfusion culture with cell retention. For this, merely four additional parameters had to be defined to extend the suspension model to fixed-bed cultures. Experimental trends and steady states of both biomass fractions besides substrate and product could be described very well. Thus, this model could be used for process layout during process development.

The plant natural products are chemical compounds or substances produced by plants and have different activities or functions. These products exhibited several important biological activities such as antimicrobial, anti-allergic, antiinflammatory, antioxidant and free radical scavenging due to their rich content of compounds as polyphenols. The highly reactive oxygen species (ROS) generated during the metabolism can cause oxidative damage for biomolecules as RNA and DNA, resulting in cell cellular damage and death. It was shown that the antioxidant activities found in plant natural products could provide protective effects via inhibiting DNA oxidative damage. This review highlights some of important roles of the plant natural products as antioxidants and as antimicrobials.

This work established a microwave-assisted procedure for polysaccharide extraction from Polygonatum odoratum. Response surface methodology was used to optimize microwave-assisted extraction parameters (extraction temperature, water-to-raw material ratio, microwave power, and extraction time) by implementing a three-level, fourvariable Box–Behnken experimental design in a single-factor investigation. Three-dimensional response surfaces were plotted by Design-Expert, and result indicated the absence of interaction effects of extraction temperature and microwave power. A polysaccharide yield of approximately 17.49% was obtained under the following optimized conditions: temperature of 57°C, microwave power of 300 W, extraction time of 10 min, and water-to-raw material ratio of 23:1. The results of preliminary in vitro antitumor activity tests showed that polysaccharides derived from P. odoratum could inhibit growth of A549 cells in a dose-dependent manner. Moreover, 4-400 μg/mL of these polysaccharides exerted no significant cytotoxicity to Panc-1 cells.

The purpose of this research was to study infant mortality and their rates in Duval County, Florida. Infant mortality rate is the estimate of infant deaths per 1,000 live births. The U.S. Infant Mortality Rate (IMR) currently ranks 27th among industrialized countries, with wide and persistent disparities by race, socioeconomic status, and geography. The objective of this research was to study infant mortality rates in each zip code in Duval County along with demographic information such as poverty, household income, prenatal care, and education. An analysis of the data collected was then used to establish whether there is a correlation between as poverty, household income, prenatal care, and education with infant mortality rates in zip codes with the highest and lowest infant mortality rates. The data for this research was gathered through the Florida Health department and nefloridacounts.org. The infant mortality rates and demographic information was sourced from the year 2014.