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Polyhydroxybutyrate (PHB), a microbial polyester well known for its high glass transition and melting temperatures, is found in the intracellular granule within microbes. Herein, we have attempted to synthesize PHB along with xyloglucan (XG) as a copolymer to lower glass transition and melting temperature. Fourier transform infrared spectroscopic (FTIR) and Scanning Electron Microscopic (SEM) analyses were used to investigate the characteristics of blend films. We found that the addition of XG resulted in increased moisture absorption of the blend films. XG-PHB blend of ratio 80 : 20 showed the highest tensile strength and was subjected to thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. The results revealed that the XG-PHB blend has a lower melting point (121.3°C) and lesser crystalline degree (17.26%) than PHB. TGA results showed that blend film was more thermally stable than PHB. An effort to understand and analyze microorganisms that can produce and biodegrade copolymers such as PHB-XG is the main effort of this study which unfolds “new hope” in the field of biodegradable alternatives to plastics.

Moronic acid is a pentacyclic triterpenoid that derives from a hydride of an oleanane. It may contain an array of olean-18-ene compounds substituted at positions 3 and 28 by an oxo group and a carboxyl group, respectively. The moronic acid and its homologies isolated from Rhus javanica have become famous for their antivirus activity against herpes simplex virus also known as human alpha herpes virus (HSV). Besides, moronic acid and its derivatives have shown antihyperglycemic action mediated by an insulin sensitization in rat models and antiinflammatory activity as indicated by in vitro and in silico studies. Moronic acids are the main constituents of Phoradendron reichenbachianum extract, a medicinal plant used in Mexico for the treatment of diabetes. The chapter describes the origin, extraction, antidiabetic, anti-HIV, antitumor, antiinflammatory, and antihistaminic potential of moronic acid.

Polyhydroxybutyrate (PHB), a biodegradable polymer (an intracellular product) was produced using Bacillus safensis EBT1. A kinetic model that describes microbial growth, biopolymer production and substrate consumption was used to predict the performance of batch fermentation of Bacillus safensis EBT1. The experimental data were fitted with modified logistic equation. The specific growth rate (μmax) and half saturation constant (Ks) values for the models such as Monod, Contois and Herbert were found to be 0.16, 0.15, 0.13 h−1 and 79.51, 68.19, 43.39 g/L respectively. Leudeking-Piret kinetics indicated that PHB formation in this study as growth associated. The recovered polymer was characterized using Transmission Electron Microscopy, Differential Scanning Calorimetry, Thermogravimetry analysis and Nuclear Magnetic Resonance. The PHB produced was used to synthesize nanoparticles using modified nano-precipitation method.

In the present work, the bioaccumulation study of electroplating industrial waste water using Micrococcus cascolyticus was carried out. The characteristics of the wastewater (pH, BOD, COD, TDS) were analyzed using standard method and it was found to be above permissible limit. The preliminary analysis for the bioaccumulation process was done by spread plate method and the concentration of the Nickel and Zinc was determined using standard method. After the bioaccumulation treatment, the aforesaid parameters were found to be below the permissible limit as prescribed by pollution control board. The removal percentage of Nickel and zinc present in the treated effluent was found to be 44.68 % and 48.76 % respectively. The maximum biomass for the Nickel and Zinc was found to be 5.8 g/l and 4.8 g/l respectively. For better bioaccumulation process, the parameters such as pH, Temperature, microbial volume, were optimized. The optimized temperature for the removal of Nickel and Zinc was found to be 50°C and 55°C respectively. Thus the Micrococcus cascolyticus has an ability to reduce the heavy metals concentration and other parameters (pH, BOD, COD, TDS) present in the waste water at the promising level.

The kinetic model of cell growth is substantially capable to predict product formation. Mathematical models provide a strategy for solving problems encountered in fermentation process. A biochemical engineering approach to address this problem could be to develop a mathematical model which not only helps in the understanding of the system but also predicts various cultivation strategies to facilitate the optimization of a fermentation process, saving much of the time and cost for performing experiments. The presented overview indicates that many of the environmentally relevant aspects in growth kinetics are still waiting to be discovered, established, and exploited. A kinetic model that describes microbial growth, product formation and substrate consumption and the experimental data were fitted with modified logistic equation.