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The esterification of guar gum hydrolysate (GGH) by dodecenyl succinic anhydride (DDSA) was optimized to a degree of substitution (DS) of 0.029 by performing the reaction at 45 °C for 2 h using 3% DDSA (w/w basis of GGH) with added 0.5 g of NaHCO3. The GGH-DDSA ester formation was confirmed by FTIR. The emulsification and subsequent microencapsulation of soybean oil by GGH-DDSA vis-a-vis gum Arabic (GA) and n-octenyl succinylated ester of GGH (GGH-OSA) as wall materials was compared. All the three wall materials stabilised the emulsions over 24 h, their spray dried microcapsules showed smooth surface without fissures, and microencapsulation efficiency was in the order of GGH-DDSA (DS 0.029) = GA > GGH-OSA (DS 0.07). The higher chain length of DDSA over OSA was advantageous for microencapsulation of lipophilic core. GGH-DDSA can be a potentially effective and efficient replacement for GA for encapsulation of lipophilic constituents.

Proteins and polysaccharides are among the biopolymers produced by living organisms for their structural integrity, protection, physiological functions, or as reserve energy. These biopolymers are extracted from their natural matrices by humans to fulfil basic as well as convenience needs. The inquisitive human nature, ever-growing demands and resources at disposal have led to copious research in the field of biopolymer modifications. The availability of reactive sites on these biopolymers make them suitable substrates for esterification, etherification, oxidation, epoxidation, N-acylation, alkylation, etc. Dodecenyl succinic anhydride (DDSA) is an esterifying agent that introduces a 12-carbon hydrophobic chain in the structure of the substrate containing suitable reactive sites. The use of DDSA as a modifying agent for biopolymers dates back to the mid-twentieth century. Even today, many biopolymers are explored for modification with DDSA for improved functionality. These modifications are aimed at catering the needs of the paint, pharmaceutical, cosmetic, food and textile industries. This review attempts to systematically compile reported research on the use of DDSA as a biopolymer modifying agent, the various reaction techniques, properties and applications thereof.

In this paper, the application of pattern search algorithm (PS) in conjunction with the well known algorithm “particle swarm optimization” (PSO) has been explored in the area of automatic generation control for multi area interconnected thermal power system. The resultant hybrid algorithm named as “hPSO-PS” has been applied to optimize the parameters of proportional integral controllers in the two areas of power plant. The control optimization problem has been defined with lower and upper bounds of the controller's parameters along with the ITAE as an objective function. The simulation results have also been compared with the previously proposed PSO/PI and PSO/PID approach in the literature and the results show that the approach hPSO-PS/PI proposed here provides far better results than PSO/PI and PSO/PID for the same system and same ITAE as an objective function in terms of the less settling times and peak overshoots, better dynamic responses, quick response of returning back to the zero frequency as well as the tie line power deviations with fewer oscillations. The results have been simulated in MATLAB environment.