M. Sukumar

Antimicrobial and antioxidant effects of spice extracts on the shelf life extension of raw chicken meat

The antimicrobial and antioxidant effects of different spice extracts in raw chicken meat during storage for 15 days at 4 °C were studied. Raw chicken meat was treated with BHT (positive control), Syzygium aromaticum (SA), Cinnmomum cassia (CC), Origanum vulgare (OV), and Brassica nigra (BN) extracts and the different combinations as well as the results were compared to raw chicken meat without any additive (negative control). The antioxidant and antimicrobial activities of spice extracts were determined. Total phenolic contents and flavonoid contents were ranged from 14.09 ± 0.78 to 24.65 ± 0.83 mg of GAE/g and 7.07 ± 0.15 to 12.13 ± 0.24 mg of quercetin/g, respectively. The pH, instrumental color (CIE L*, a*, b*), total viable counts (TVC), Lactic Acid Bacteria (LAB) counts, Enterobacteriaceae counts, Pseudomonas spp. counts and 2-thiobarbituric acid reactive substances (TBARS) were determined at a gap of 3 days interval for a period of 15 days. The bacterial counts of T-W-SA+T-W-CC+T-W-OV samples were lower than control samples during storage. T-W-SA+T-W-CC+T-W-OV samples maintained significantly (P<0.05) higher L*, a* and b* values while storing. The TBARS values of T-W-SA+T-W-CC+T-W-OV samples were lowest among the samples. These results show that spice extracts are very effective against microbial growth, lipid oxidation and has potential as a natural antioxidant in raw chicken meats.

Preparation and characterization of mucilage polysaccharide for biomedical applications

In the present investigation, the polysaccharide/mucilage from waste of Abelmoscus esculentus by modification in hot extraction using two different solvents (Acetone, Methanol) were extracted, characterized and further compared with seaweed polysaccharide for their potential applications. The percentage yield, emulsifying capacity and swelling index of this mucilage were determined. The macro algae and okra waste, gave high % yield (22.2% and 8.6% respectively) and good emulsifying capacity (EC%=52.38% and 54.76% respectively) with acetone, compared to methanol (11.3% and 0.28%; EC%=50%) (PH=7) while swelling index was greater with methanol than acetone extracts respectively. The infrared (I.R.) spectrum of the samples was recorded to investigate the chemical structure of mucilage. Thermal analysis of the mucilage was done with TGA (Thermal Gravimetric Analyzer) and DSC (Differential Scanning Calorimeter) which showed both okra and algal polysaccharide were thermostable hydrogels.

Microbial desalination cell for enhanced biodegradation of waste engine oil using a novel bacterial strain Bacillus subtilis moh3

Microbial desalination cell (MDC) is a bioelectrochemical system developed recently from microbial fuel cells (MFCs), for producing green energy from organic wastes along with desalination of saltwater. MDC is proved to be a better performer than MFC in terms of power output and chemical oxygen demand removal, with desalination as an additional feature. This study investigates the application potential of MDC for integrated biodegradation of waste engine oil. This study showed, for the first time, that waste engine oil could be used as an organic substrate in MDC, achieving biodegradation of engine oil along with considerable desalination and power production. Utilization of these wastes in MDC can protect the environment from waste engine oil contamination. Indigenous oil-degrading bacteria were isolated and identified from engine oil contaminated sludge. Degradation of waste engine oil by these novel isolates was studied in batch cultures and optimized the growth conditions. The same cultures when used in MDC, gave enhanced biodegradation (70.1±0.5% ) along with desalination (68.3±0.6% ) and power production (3.1±0.3 mW/m2). Fourier transform-infrared spectroscopy and gas chromatography-mass spectrometry analyses were performed to characterize the degradation metabolites in the anolyte of MDC which clearly indicated the biodegradation of long chain, branched and cyclic hydrocarbons present in waste engine oil.

Production and characterization of cellulose reinforced starch (CRT) films

Starch from Tamarind seed is considered to be a nonedible and inexpensive component, with many industrial applications. Extraction and characterization of tamarind seed starch was carried out for the synthesis of biopolymer. Tamarind seeds were collected, cleaned and further roasted, decorticated, and pulverized to get starch powder. Total starch content present in each tamarind seed is estimated to be around 65-70%. About 84.68% purified starch can be recovered from the tamarind seed. Defatted Tamarind seed starch has an amylose content of 27.55 wt.% and 72.45 wt.% of amylopectin. Morphological (SEM) and X-ray diffraction were used to evaluate crystallinity. Likewise, TGA and DSC of starch have also been analyzed. Thermal properties of starch obtained from tamarind seeds showed good thermal stability when compared to other starch sources such as Mesquite seed and Mango kernel. This study proved that the tamarind seed starch can be used as a potential biopolymer material. Thermo-stable biofilms were produced through initial optimization studies. Predictive response surface quadratic models were constructed for prediction and optimization of biofilm mechanical properties. Correlation coefficient values were calculated to me more than 0.90 for mechanical responses which implies the fitness of constructed model with experimental data.

Integrated Approach to the Problems of Dye Wastewater by Sonolysis and Biological Treatment

The degradation of a reactive dye by combined sonolysis (40 kHz) and biodegradation was studied using Acid red (AR 66) as a model dye. The combined action of ultrasound and biodegradation using Bacillus subtilis was characterized as a function of dye concentration, pH and temperature. Under optimum conditions, AR 66 could be completely degraded within 10 h. The COD analysis was performed and was found that about 90-95% COD reduction was achieved by this hybrid technique. The biodegradation data for AR 66 were fitted to Bridge- Haldane equation with good correlation.

Potential application of corn starch edible films with spice essential oils for the shelf life extension of red meat.

To investigate the effect of corn starch (CS) edible films with spice oils on the stability of raw beef during refrigerated storage.

Bio protection and preservation of raw beef meat using pungent aromatic plant substances

BACKGROUND This study examined the effectiveness of three individual spice (clove, cinnamon and oregano) extracts and their combinations in raw beef meat during refrigerated storage. Meat samples were monitored for microbiological (total viable count, Enterobacteriaceae, lactic acid bacteria, Brochothrix thermosphacta and Pseudomonas spp.) and physicochemical (pH, colour and thiobarbituric acid-reactive substances (TBARS)) attributes. RESULTS Samples treated with the combination of all three spice extracts showed lower bacterial counts and better L*, a* and b* values among treated samples during the storage period. Positive and negative control samples had the highest TBARS values at the end of the storage period. With the addition of spice extracts, TBARS values in raw beef samples were retarded effectively (P < 0.05) compared with control samples, especially when the combination of all three spice extracts was used. CONCLUSION The results of this study show that spice extracts were effective in inhibiting the growth of microbial populations and retarding lipid oxidation during refrigerated storage (4 °C) of raw beef meat. They also suggest that combinations of these extracts may have potential as natural preservatives in raw meat products.

Effect of Punica granatum peel extracts on antimicrobial properties in Walnut shell cellulose reinforced Bio-thermoplastic starch films from cashew nut shells

The main aim of the present study is to extract and characterize cashew nut shell (CNS) starch and walnut shell cellulose (WNC) for development of cellulose reinforced starch films. Moreover, the extraction and characterization of pomegranate peel extract, for incorporation with CNS-WNC films, was investigated. CNS starch was examined to be a moderate amylose starch with 26.32 ± 0.43% amylose content. Thermal degradation temperature of CNS starch was found to be 310 °C. Walnut shell cellulose was found to have high crystallinity index of 72%, with two thermal degradation temperatures of 319 °C and 461 °C. 2% WN cellulose reinforced CNS starch films were examined to have good oxygen transfer rate, mechanical and physical properties. Thermal degradation temperature of CNS-WNC starch films were found to be at the range of 298-302 °C. Surface roughness of CNS-WNC starch films were found to be increasing with increase in concentration of cellulose in films. Hydroxymethylfurfurole, Benzene, 2-methoxy-1,3,4-trimethyl and 1,2,3-Propanetriol, 1-acetate were found to be major active compounds present in hydrophilic extracts of Punica granatum peels. 2% WN cellulose reinforced starch films infused with hydrophilic active compounds of pomegranate peel was examined to be having good active package properties.

Extraction and characterization of polysaccharides from tamarind seeds, rice mill residue, okra waste and sugarcane bagasse for its Bio-thermoplastic properties

The aim of the present study is to extract potential thermoplastic polysaccharides from agricultural industrial wastes. Polysaccharides were extracted from renewable agro industrial wastes such as tamarind seeds [rich in starch (TSS)], okra head waste [rich in mucilage polysaccharide (OMP)], sugarcane bagasse [rich in cellulose (SBC)] and residual rice mill wastes [rich in starch and fiber (RS)]. Urigam variety of tamarind seed starch found to be an amylose rich starch. Different polysaccharides extracted from agro wastes were found to be having high thermal stability, except okra polysaccharide (comparatively low). X-ray diffraction pattern of tamarind seed starch proved its high crystallinity index. Crystallinity index of investigated polysaccharides were found to be in the order of SBC > TSS > RS > OMP. Chemical nature of extracted polysaccharides was confirmed by Fourier transform infrared spectroscopic analysis. Residual rice bran starch granules and tamarind seed starch globules were found to be having comparatively reduced particle size than sugarcane bagasse cellulose and okra mucilage. Scanning electron microscopic analysis revealed the cluster formations of RS granules and TSS globules. Residual rice bran starch found to be associated with other fibers (present in outer coat of rice). Okra mucilage and SBC were examined to be having linear sheets and linear bundles structures, respectively.

Active compound diffusivity of particle size reduced S. aromaticum and C. cassia fused starch edible films and the shelf life of mutton (Capra aegagrus hircus) meat

In the present study, mathematical models were used to examine the effect of active compound diffusion from edible film (supplemented with S. aromaticum and C. cassia) on the microbial, physical and chemical quality of mutton stored at 4 and 10°C. Cinnamaldehyde and eugenol release from edible film into liquid was found to be 80% and 75% of the equilibrium concentration. Active compound release into meat was 42-51% for cinnamaldehyde and 38-48% for eugenol, in storage temperatures of 4-15°C. Developed mathematical models showed the diffusivity of cinnamaldehyde (0.45×10-15±0.04×10-15) and eugenol (0.63×10-10±0.01×10-10) into meat, which was about 40% of that in liquid medium. On comparing physical, chemical and microbial results, shelf life of mutton meat was found to be increased by 1week at storage temperature of 10°C and 3weeks at storage temperature of 4°C.