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The current study emphasizes the activated carbon fabrication from rubber fig leaves, the establishment of its composite with iron oxide nanoparticles (RFAC@Fe

Herein, the sustainable fabrication of magnetic iron oxide nanoadsorbent prepared with activated carbon of inedible Cynometra ramiflora fruit has been investigated. Activated carbon was obtained from phosphoric acid-treated C. ramiflora fruit, which was then utilized for the synthesis of magnetic nanocomposite (CRAC@Fe

In the present study, ferric oxide nanoparticles impregnated with activated carbon from Ulva prolifera biomass (UPAC-Fe

This paper focuses on the use of Cyclea peltata leaf extract for green synthesis of silver nanoparticles (CPL-AgNPs) post-optimization by one variable at a time (OVAT) approach for nonlinear optics application. The leaf extract of Cyclea peltata (10% w/v) and AgNO3 (1 mM) was used for the synthesis of silver nanoparticles (CPL-AgNPs). Reactions conditions like CPL extract concentration, salt concentration, temperature, pH, RPM, and time for synthesis were optimized by using OVAT approach. A UV-visible spectroscopic investigation confirmed the biosynthesis of CPL-AgNPs at 420 nm. Field emission scanning electron microscope (FESEM) confirmed the spherical monodispersed nanoparticles in the range of 30–50 nm and EDAX confirmed the purity of the sample. FTIR confirmed the capping of nanoparticles by plant phytochemicals. The synthesized CPL-AgNPs were evaluated for nonlinear optical properties using the Z-scan technique at 532 nm with a CW laser. Strong nonlinear absorption by the nanoparticles in the range of 2.85 × 10−2 cm/W was observed. Moreover, CPL-AgNPs display superior optical limitations.

This study deals with the synthesis of hydroxyapatite nanoparticles (HAPnps) mediated by Acacia falcata leaf extract. Aggregates of needle-shaped crystalline nanostructures were confirmed by FE-SEM and TEM analysis. Well-defined rings in the SAED patterns corroborated the polycrystalline nature of the HAPnps. Individual elements present in the HAPnps were attested by the specific signals for Ca, P, and O in the EDS and XPS analyses. The distinct peaks observed in the XRD spectrum matched well with the HAP hexagonal patterns with a mean crystallite size of 55.04 nm. The FTIR study unveiled the coating of the nanoparticles with the biomolecules from Acacia falcata leaves. The suspension HAPnps exhibited polydispersity (0.446) and remarkable stability (zeta potential: - 31.9 mV) as evident from DLS studies. The pore diameter was 25.7 nm as obtained from BET analysis, suggesting their mesoporous nature. The HAPnps showed the cytotoxic effect on A549 lung and MDA-MB231 breast carcinoma cell lines, with an IC

Heavy metals are dumped into the environment as a result of human activities, posing a serious threat to ecology and human health. Surface water, potable drinking water, potable groundwater, and majority of wastewater include their traces, due to which, their detection by nanoparticles has received a lot of attention in recent years. Although microorganisms are utilized for green nanoparticle production, plant materials have recently been explored because they are more environmentally friendly, easier to scale up, and require fewer specific growth conditions. The production and attributes of nanoparticles synthesized by plant mediation could be enhanced through design of experiments approach, extending their feasibility in the detection of heavy metals in polluted environmental samples. A concise review on green synthesis of silver and gold nanoparticles utilizing plant phytochemicals, its mechanism of synthesis along with significance of design of experiments for enhancement, and their use as heavy metal contamination detectors is presented in the current study.

Effect of oil spills on living forms demands for safe, ecofriendly and cost-effective methods to repair the damage. Pseudomonads have exceptional tolerance to xenobiotics and can grow at varied environmental conditions. This study aims at biosurfactant mediated degradation of petroleum crude oil by an indigenous Pseudomonas sp. WD23 in sea water. Pseudomonas sp. WD23 degraded 34% of petroleum crude oil (1.0% v/v) on supplementation of yeast extract (0.05 g/L) with glucose (1.0 g/L) in seawater. The strain produced a biosurfactant which was confirmed as a rhamnolipid (lipid: rhamnose 1:3.35) by FT-IR, LCMS and quantitative analysis. Produced rhamnolipid had low CMC (20.0 mg/L), emulsified petroleum oils (75-80%) and had high tolreance to varied conditions of pH, temperature and ionic strength. OFAT studies were performed to analyse the effect of petroleum crude oil, glucose, inoculum, yeast extract, pH, agitation speed and incubation time on degradation by Pseudomonas sp. WD23. Petroleum crude oil and glucose had significant effect on biodegradation, rhamnolipid production and growth, further optimized by central composite design. At optimum conditions of 3.414% v/v PCO and 6.53 g/L glucose, maximum degradation of 81.8 ± 0.67% was observed at pH 7.5, 100 RPM, 15.0% v/v inoculum in 28 days, with a 3-fold increase in biodegradation. GCMS analysis revealed degradation (86-100%) of all low and high molecular weight hydrocarbons present in petroleum crude oil. Hence, the strain Pseudomonas sp. WD23 can be effectively developed for management of oil spills in seas and oceans due to its excellent degradation abilities.

Bacillus sp. WD22, previously isolated from refinery effluent, degraded 71% of C8 hydrocarbons present in 1.0% v/v PCO in seawater (control medium), which reduced to 16.3%, on addition of yeast extract. The bacteria produced a biosurfactant in both media, whose surface was observed to be amorphous in nature under FESEM-EDAX analysis. The biosurfactant was characterized as a linear surfactin by LCMS and FT-IR analysis. The critical micelle concentration was observed as 50 mg/L and 60 mg/L at which the surface tension of water was reduced to 30 mN/m. Purified biosurfactant could emulsify petroleum-based oils and vegetable oils effectively and was stable at all tested conditions of pH, salinity and temperature up to 80 °C. The biosurfactant production was found to be mixed growth associated in control medium, while it was strictly growth associated in medium with yeast extract as studied by the Leudeking-Piret model.

The present study aimed at the synthesis of cobalt oxide nanoparticles (CONPs) mediated by leaf extract of Muntingia calabura using a rapid and simple method and evaluation of its photocatalytic activity against methylene blue (MB) dye. UV-vis absorption spectrum showed multiple peaks with an optical band gap of 2.05 eV, which was concordant with the literature. FESEM image signified the irregular-shaped, clusters of CONPs, and EDX confirmed the existence of the Co and O elements. The sharp peaks of XRD spectrum corroborated the crystalline nature with a mean crystallite size of 27.59 nm. Raman spectrum substantiated the purity and structural defects. XPS signified the presence of Co in different oxidation states. FTIR image revealed the presence of various phytochemicals present on the surface and the bands at 515 and 630 cm

Cocoa pod shells are the agro waste generated causing problem during the disposal. In the present study, possibility of utilizing the cocoa pod shells to release the reducing sugars has been explored. Hydrochloric acid hydrolysis assisted with autoclave was adopted to obtain reducing sugars. The one parameter at a time approach was implimented to screen the significant parameters influencing the hydrolysis among weight of cocoa pod shells, concentration of HCl and duration of autoclave. Parameters such as concentration of HCl and duration of autoclave were found to be significant. These parameters were chosen for the central composite design comprising of five levels using response surface methodology to optimize the hydrolysis process. At optimized condition of 54.15 minutes of autoclave treatment and 4.41% of HCl, 21.11 g/L of maximum reducing sugar was released. A second order polynomial equation was generated having a good fit with R2 of 0.84.

Global industrialisation and overexploitation of fossil fuels significantly impact greenhouse gas emissions, resulting in global warming and other environmental problems. Hence, investigations on capturing, storing, and utilising atmospheric CO

The manual selection of transformed bacterial colonies from non-transformed ones grown on agar plate post-blue-white screening – despite chromogenic difference – is cumbersome, owing to their small size and large cell number. The present study offers a lucrative solution to this problem by the design of an automated system that is not only fast and less laborious but also low priced and user-friendly. The image masking technique was used to distinguish plated transformed colonies. This method uses computer vision techniques to detect the number of blue and white colonies post bacterial transformation on agar plates and calculate the transformation efficiency. To assess the proposed model with the manual counting method, we have validated the model by comparing the manual counting of colonies with the automated system count. Hence, a model was developed that would be an added advantage to biotechnologists as it would minimize the time required for counting and help in productive research.

Cocoa pod shell (CPS) is an underutilized agricultural lignocellulosic biomass. Hydrochloric acid (HCl) hydrolysis was carried out to release the reducing sugars from CPS. The conditions (CPS weight, concentration of HCl, revolutions per minute, hydrolysis period) which affect HCl hydrolysis were screened using one factor at a time approach of which determined that CPS weight, HCl concentration and hydrolysis period had a significant effect on the acid hydrolysis process. The levels of these factors were further optimized using a central composite design using response surface methodology. The optimized conditions were 8.36% (weight per volume) of CPS, 3.6 N of HCl concentration with 7.36 h of acid hydrolysis which yielded 4.09 g/L reducing sugars. A second order model was generated and validated, which was found to be a good fit (coefficient of determination = 0.914). The released reducing sugars after the acid hydrolysis under optimized conditions were subjected to alcoholic fermentation by Pichia stipitis to produce bioethanol. The bioethanol concentration reached 2 g/L at 2% (volume per volume) inoculum concentration after 72 h of fermentation. Keywords: Bioethanol, Cocoa pod shell, Optimization, Reducing sugars

The use of microbial extracellular polymeric substances (EPS) as bioflocculants opposed to synthetic and organic flocculants in the treatment of heavy metal polluted wastewater is currently gaining importance. The present study focuses on the characterization and application of EPS produced by Lysinibacillus sp. SS1 in heavy metal removal. Lysinibacillus sp. SS1 (10%v/v), isolated from used engine oil contaminated soil, produced EPS and circular white spongy masses on the utilization of 3% petroleum crude oil (PCO) in the Bushnell Haas medium in 10 d. Analysis of extracted EPS and masses revealed that it contained carbohydrates, lipids, and proteins in proportions of 1.3: 94.6: 3.6 and 2.3: 91.5: 6.2, respectively. Characterization by LCMS and FT-IR analysis confirmed that they were predominantly lipids with proteins and polysaccharide groups. Masses could remove 48% of lead and 40% of mercury from aqueous solutions by adsorption on their surface as confirmed by SEM-EDAX. Extracted EPS (100 mg/L) could remove 94.9% of lead from aqueous solution (150 mg/L) in 72 h by precipitation of lead as nanoparticles of sizes ranging from 30–40 nm. This study shows the potential of Lysinibacillus sp. SS1 and its EPS in response to PCO in heavy metal removal and recovery.

The objective of the present study was to optimise the biosynthesis of gold nanoparticles using aqueous extract of Pongamia seed cake (PSC). Proteins, amino acids and phenolic compounds present in the PSC extract are responsible for reducing the metal precursor salt to nanoparticles. The levels of factors for optimisation of nanoparticles synthesis was evaluated using UV–Vis spectrophotometer by one factor at a time studies. Further factorial design was employed to study the significant effect of various parameters on the nanoparticles synthesis. The levels of two significant factors i.e. pH and concentration of PSC extract as obtained from factorial design were optimized further for maximum nanoparticle synthesis applying central composite design. The optimized conditions were found to be pH 3.6 and PSC extract concentration of 17.07% (w/v) at which an increase (OD at 530 nm = 1.3) in nanoparticle synthesis was observed as compared to un-optimized conditions (OD at 530 nm = 0.66). The model obtained on optimization was validated and it describes the nanoparticle synthesis aptly with an error between experimental and predicted values of just 1.15% with an R2 of 0.985. It can be concluded that, RSM approach was found to be an efficient technique to optimize the reaction conditions, where a twofold increase in synthesis of small sized monodispersed gold nanoparticles was seen.

The utilization of coconut leaflets, an agro residue generated from coconut farming, was investigated to develop a process to release reducing sugars using hydrochloric acid (HCl)-assisted, autoclave-based hydrolysis. The variables affecting HCl hydrolysis (duration of autoclaving, concentration of HCl and weight of coconut leaflets) were screened using a one factor at-a-time approach. The duration of autoclaving and concentration of HCl both had significant effects on the hydrolysis process and the levels of these factors were further optimized using a central composite design with response surface methodology. The optimized conditions were 3.17% of HCl and 44.14 min of autoclaving that released the maximum reducing sugars of 29 g/L. A second order model was generated, which was a good fit with a coefficient of determination value of 0.83. Keywords: Acid hydrolysis, Coconut leaflets, Optimization, Reducing sugar

To release reducing sugars from cocoa pod shell, sulphuric acid pre-treatment was adopted where the variables affecting H2SO4 pre-treatment i.e., cocoa pod shell weight, H2SO4 concentration, microwave irradiation time and power were screened using one factor at a time approach. The weight of cocoa pod shell, concentration of H2SO4 showed a significant effect on the pre-treatment process and the levels of these factors were further optimized by central composite design using response surface methodology .The optimized conditions were found to be 15.65g ofcocoa pod shell, 6% v/v H2SO4 at 8 min of irradiation, released maximum reducing sugar of 9.10 g/L. A second order model was generated and validated, which was found to be a good fit with R2value of 0.89. Artificial neural network modelling proved validation R2 of 0.94 comparatively better than Response surface methodology R2 of 0.89. The reducing sugars released after acid hydrolysis at optimized conditions were subjected to fermentation by Pichia stipitis to produce bioethanol. The bioethanol produced was 3.2g/L at 2% (v/v) inoculum concentration after 72h of fermentation.

Highlights • Kleibsiella pneumoniae Kpn555 tolerates 900 mg/L lead. • SEM and TEM studies revealed surface deposition and bioaccumulation of lead. • Surface deposition mediated by EPS produced in response to lead stress, characterised as glycolipid with protein moieties. • Maximum biosorption ability of EPS – 475 mg/g. • Ability of lead bioaccumulation is plasmid mediated., Kleibsiella pneumoniae Kpn555, isolated from coffee waste pulp showed high level of tolerance to lead with a minimum inhibitory concentration of 900 mg/L. On its growth in nutrient broth supplemented with lead, brown clumps were visualised at the bottom of the flask. On scanning and transmission electron microscopic studies the brown clumps were corroborated to be bacterial cells with lead biosorbed on the cell surface and accumulated inside the cytoplasm. Biochemical and FT-IR analysis of the extracellular polymeric substance produced on exposure to lead revealed its chemical nature as glycolipid with protein moieties. Purified EPS (100 mg/L) could remove 50% of lead from aqueous solution (200 mg/L). Isolation of plasmid from Klebsiella pneumoniae Kpn555 revealed the presence of a plasmid of size 30–40 kb. This capability of the bacteria was proven to be plasmid mediated as the Escherichia coli DH5α cells transformed with the plasmid of Klebsiella pneumoniae Kpn555 also could tolerate 900 mg/L of lead and form brown clumps. This study shows that these bacteria, aided by EPS could serve as an effective agent for the removal of lead from contaminated water environmental samples., Graphical abstract Image, graphical abstract

Nature has its hidden battalion against all the manmade environmental contaminations. Ethno-medicinal plants and their hidden microbiome are the natural treasures that are in need to be explored The present work is focused on isolating the endophytic bacteria of Annona reticulata, Cinnamomum zeylanicum and Gloriosa superba Isolated bacterial strains are screened for the potential degrader of 2,4-D depending on their efficiency to tolerate a higher mg.L−1 of 2,4-D. Enterobacter hormaechei Subsp. xiangfangensis strain 19_357_F (MK281611), isolated from the bark explant was capable of co-existing and utilizing 2,4-D as a source of nourishment, thus degrading 2,4-D to 2,4-DCP. The optimization of biodegradation was carried out using one factor at a time (OFAT) approach and the isolated strain could tolerate 400 mg.L−1 of 2,4-D while degrading 250 mg.L−1 of dye accounting for 42.68% degradation at 72 h. The present study indicates the endophyte Enterobacter hormaechei subsp. xiangfangensis strain 19_357_F capable of utilizing 2,4-D as the sole source of energy, on further increasing the 2,4-D above 400 mg.L−1 the bacterial toxicity was induced demonstrating the reduction in the bacterial cell count The current study also reported the biodegraded metabolite 2,4-DCP more toxic than the parent compound and suggestive of increasing the time of incubation. The endophyte Enterobacter hormaechei subsp. xiangfangensis strain 19_357_F is considered efficient as it can degrade 2,4-D at 250 mg.L−1 with 42.68% quantitatively. The aim of the study is to explore these potential organisms as tool for bioremediation and enhance the environmental self-sustainability as these endophytes are safer, reliable, non-pathogenic and eco-friendly.

Most of the probiotic functional beverages are dairy based and cannot be consumed by lactose intolerant people. In this study, growth of probiotic Lactobacillus plantarum SVP2 and its exopolysaccharide (EPS) production was studied in natural sources such as coconut water and sugar cane juice with soyabean and green gram extracts as protein sources. Among four combinations tested, highest growth (18.74 ± 0.33 g/L) and EPS (11.89 ± 0.42 g/L) was achieved in coconut water based medium supplemented with soyabean protein (0.25 g/L) and sucrose (10 g/L). Therefore, EPS production by L. plantarum SVP2 was optimized in coconut water-soyabean protein medium by one factor at a time (OFAT) analysis considering factors such as concentrations of sucrose, soyabean protein and inoculum, temperature, agitation speed and fermentation time. The fermented functional beverage was prepared by supplementing coconut water with 40 g/L sucrose, 0.75 g/L soyabean protein, 1.5% v/v inoculum at 27 °C, 100 RPM for 36 h (optimized conditions) during which maximum EPS of 64.17 ± 0.61 g/L was produced. The cell count, pH and EPS amount in fermented beverage remained almost similar on storage of product in refrigerated conditions for 7 days. Although, sensory analysis performed on synthesized beverage and beverage stored at refrigerated conditions revealed moderately high acceptance of flavour and texture, overall acceptability among consumers was average attributing to colour and slightly sour fermented odour. Consumption of this fermented functional beverage offers multiple benefits owing to antibacterial, anti-biofilm properties of EPS and probiotic L plantarum.

Use of novel biological materials as adsorbents for removal of xenobiotics is gaining significance owing to their exceptional advantages. An extracellular polymeric substance (EPS) produced by Lysinibacillus sp. SS1 had rough porous surface as observed by SEM analysis. Adsorption ability of EPS was estimated against various textile dyes such as Malachite Green (MG), Methyl Orange, Congo Red and Coomassie Blue. About 82% of MG (100 mg/L) was adsorbed onto 2.5 mg EPS within 30 min. Effect of MG concentration, EPS weight, agitation speed and incubation time on adsorption, studied by one factor at a time approach, revealed that adsorption was influenced by all factors. Maximum adsorption of 99.01 ± 0.61% was achieved at 100 mg/L MG, 10 mg EPS, 120 RPM in 75 min with maximum adsorption capacity of 247.5 mg/g. Kinetics was affected by MG and EPS amounts, with shift from pseudo first to pseudo second order with increase in concentration. Adsorption of MG by EPS of Lysinibacillus sp. SS1 was identified as unilayer chemisorption as it followed Langmuir isotherm with maximum adsorption capacity (Qm) of 178.57 mg/g (R2 = 0.9889). This is the first report on potential of EPS produced by Lysinibacillus sp. SS1 as novel biodegradable adsorbent with high efficacy of MG removal from aqueous solutions., EPS, Lysinibacillus sp. SS1, Malachite Green, Adsorption kinetics.

Intracellular lipase from Enterococcus faecium MTCC5695 (MTCC5695), a lactic acid bacterium, grown at optimal conditions was subjected to purification and concentration using aqueous two-phase extraction system (ATPS). The partitioning behavior was studied for five different phase forming salts. Molecular weight of polyethylene glycol (PEG), concentration of PEG and phase forming salt, tie line length (TLL) and phase volume ratio were optimized for the purification of E. faecium lipase. Partitioning occurred towards bottom phase of the system containing sodium dihydrogen phosphate. The optimum conditions for purification were at PEG 8000, 41.24% TLL and 0.25 phase volume ratio. Activity recovery and purification factor achieved after ultrafiltration were 5.99% and 82.09%, respectively. In addition, enzyme characterization studies revealed that MTCC5695 produced an alkaline lipase. Molecular weight of the purified lipase was about 19.2 kDa; and, the purified lipase had optimal activity at pH 10.8 and 40 °C. Stability over different pH and temperature ranges along with the effect of variety of organic solvents is also reported. Studies involving group specific modifiers indicated the role of histidine, serine, carboxylate and tryptophan in the catalytic site, which is a characteristic feature of lipases.

The pressing priority is to uncover environmentally secure techniques for abolition of oil spills suited to Indian marine conditions as increase in fuel consumption and demand has resulted in enhanced petroleum crude oil (PCO) transfer via sea route. Acinetobacter baumannii OCB1, isolated from petroleum refinery effluent, when grown in sea water supplemented with PCO (1.0% v/v) and glucose (1.0 g/L) yielded high degradation of C8 hydrocarbons (69.69%). On adding yeast extract (0.05 g/L) it degraded C8–C14 hydrocarbons (3.55–17.48%). Degradation was facilitated by lipopeptide biosurfactant (BS) having needle like surface as depicted by LCMS and FESEM analysis. Yield was higher in presence of yeast extract while there was no significant difference in activity. BS showed excellent stability at wide range of pH, temperature, salinity and high emulsification of petroleum-based oils. BS production modelled by Leudeking Piret model was growth associated and mixed growth associated without and with yeast extract respectively.

The increased modernization and urbanisation of developing countries has resulted in a tremendous spurt in use of vehicles and automobiles. As a result of this, enormous amounts of used engine oil and lubricating oils are generated which are released into soil and water bodies. Novel ecofriendly techniques must be developed to eradicate this issue. Hence, in the present study a yellow pigmented circular flat mucoid colony of Gram negative bacillus, capable of utilising used engine oil as a sole source of carbon was isolated from motor garage soil. This bacterium could degrade used engine oil on Bushnell Hass agar plates within 48 h and could decolorize 6-dichlorophenol indophenol (redox indicator) within 4 days. It was identified as Pantoea wallisii SS2 by 16s rRNA sequencing and could hydrolyse a wide range of sugars. The screening of degradation conditions such as concentrations of used engine oil, inoculum, glucose, Tween 20, and degradation time that affect the %TPH reduction in used engine oil augmented soil was performed by one factor at a time approach. The significant factors (inoculum and glucose concentration) were optimised for maximum %TPH reduction by central composite design. At optimised conditions (13.53 %v/w inoculum and 8.82 g/kg glucose), %TPH reduction of 79.8% was obtained in soil augmented with 4% v/w used engine oil, 20 mg/kg Tween 20 in 21 days. This is the first study that reports the isolation of Pantoea wallisii in motor garage soil and its use in degradation of used engine oil in soil.

Biofuels and their production is the need of the hour considering the current fuel crisis. In this regard, ways of mitigating biodiesel production costs is being actively researched upon. With the same intention, in the present work, an investigation was carried out to test the capability of utilizing the hydrolysates of de-oiled Pongamia seed cake, a byproduct of biodiesel, for microbial lipid production using Aspergillus ochraceus. This is the first time A. ochraceus is being reported to be used to evaluate its oleaginous property. Also, Pongamia seed cake is the novel source being used for microbial lipid production. The different variants of the seed cake based medium proved acid hydrolysate of de-oiled seed cake to be the effective medium for lipid production. The values recorded for maximum biomass titer, lipid titer and lipid content were 3.065 ± 0.248 g/L, 0.849 ± 0.056 g/L and 28.93%, respectively, upon using acid hydrolysate of the seed cake. The fatty acid composition obtained by GC-MS analysis revealed the presence of linoleic, oleic, stearic and palmitic acids as the major fatty acid components in the lipids produced proving their similarity to the vegetable oils. The fuel properties of the lipids produced were found be in accordance with the standard specifications making them a very good source for biodiesel production. The findings from the current study reveal the effectiveness of Pongamia seed cake for microbial lipid production and simultaneous value addition to the biodiesel industry.

Although nanoparticles can be produced using various physicochemical methods, their synthesis using nontoxic environmental friendly biological method is gaining more attention especially from the point of view of in situ application in medicine. Biological synthesis of nanoparticles is not only useful because of its very low environmental burden compared with some of the physicochemical methods, but also it can be easily scaled up without much complication. Biosynthesis of silver nanoparticle under ambient condition using turmeric extract is reported here. The formation of turmeric nanoparticles (TUAgnps) were analyzed visually and spectrophotometrically. Appearance of brownish yellow colour indicated the formation of TUAgnps which was confirmed by the appearance of surface plasmon band at 435 nm by UV-Vis spectrophotometry. The synthesized TUAgnps were characterized by FT-IR, particle size analyzer, SEM and EDAX. FT-IR studies revealed the capping of nanoparticles by phytoconstituents present in the turmeric extract, and negative zeta potential indicated the stability of TUAgnps. The synthesized nanoparticles were used for methylene blue dye reduction and as a bactericidal agent. The TUAgnps impregnated cotton bandage gauze exhibited strong antimicrobial activity against Bacillus subtilis and Pseudomonas aeruginosa which was confirmed by anticontact study. SEM image of the nanoparticle impregnated cotton bandage gauze showed TUAgnps ranged from 120 to 160 nm hence TUAgnps could be effectively used in antimicrobial wound dressing. The biosynthesized TUAgnps were observed to have a positive catalytic activity of reduction of methylene blue dye, which can be confirmed by time dependent reduction in absorbance maxima which can be ascribed to the electron relay response.

Enterococcus durans NCIM5427 (ED-27), capable of producing an intracellular acid stable lipase, was isolated from fish processing waste. Its growth and subsequent lipase production was optimized by Box Behneken design (optimized conditions: 5 % v/v fish waste oil (FWO), 0.10 mg/ml fish waste protein hydrolysates (FWPH) at 48 h of fermentation time). Under optimized conditions, ED-27 showed a 3.0 fold increase (207.6 U/ml to 612.53 U/ml) in lipase production, as compared to un-optimized conditions. Cell growth and lipase production was modeled using Logistic and Luedeking-Piret model, respectively; and lipase production by ED-27 was found to be growth-associated. Lipase produced by ED-27 showed stability at low pH ranges from 2 to 5 with its optimal activity at 30 °C , pH 4.6; showed metal ion dependent activity wherein its catalytic activity was activated by barium, sodium, lithium and potassium (10 mM); reduced by calcium and magnesium (10 mM). However, iron and mercury (5 mM) completely inactivated the enzyme. In addition, modifying agents like SDS, DTT, β-ME (1%v/v) increased activity of lipase of ED-27; while, PMSF, DEPC and ascorbic acid resulted in a marked decrease. ED-27 had maximum cell growth of 9.90309 log CFU/ml under optimized conditions as compared to 13 log CFU/ml in MRS. The lipase produced has potential application in poultry and slaughterhouse waste management.

Pre-treatment is a process that releases simple sugars from complex lignocellulosic biomass by using chemicals like acid and alkali which are one of the simplest and cost effective techniques. In this study, the conditions for sulphuric acid and sodium hydroxide pretreatment of de-oiled oil seed cake (DOSC) were optimized by response surface methodology (RSM). The levels of factors (DOSC concentration, agitation speed, sulphuric acid (H2SO4), sodium hydroxide (NaOH) concentration and reaction time) that affect release of reducing sugars by pre-treatment were obtained by one factor at a time (OFAT) approach of which only H2SO4 concentration, NaOH concentration and reaction time showed significance. The levels of factors were optimized by central composite design. Optimized conditions were found to be 11.65% (v/v) of H2SO4 concentration at 1.28h and, 4 N of NaOH at 3.7 h for acid and alkali hydrolysis respectively. Under optimized conditions, the release of reducing sugars was found to be 0.69 g/L (41.36 mg RRS/ g cellulose) and 0.40 g/L (23.98 mg RRS/ g cellulose) for acid hydrolysis and alkali hydrolysis of DOSC, respectively. Hence, RSM was found to be an efficient technique to optimize the hydrolysis process and ensure maximum release of reducing sugars.

Cocoa pod shells (CPS) are underutilized agricultural lignocellulosic biomass. To release reducing sugars from cocoa pod shells, Na2CO3 pre-treatment was carried out. In the current study the conditions for sodium carbonate treatment were optimized by response surface methodology (RSM). The screening of (CPS weight, Na2CO3 concentration, time, rpm) affecting release of reducing sugars was carried out by one factor at a time (OFAT) approach. Among the four factors screened, CPS weight and Na2CO3 concentration showed significant effect on the pre-treatment process. These significant factors were opti mized by RSM using a central composite design (CCD). At the optimized conditions of 7.82 g of CPS and Na2CO3 concentration of 0.58 N, the yield of reducing sugar was found to be 0.94 g/L. A second order model was generated and validated, which was found to be of good fit with an R2 of 0.847. These results show that RSM is an efficient methodology for rapid optimization of influencing parameters and development of polynomial equation for modelling the pre-treatment process.

Enterococcus faecium MTCC 5695 possessing potential probiotic properties as well as enterocin producing ability was used as starter culture. Effect of time (12–24 h) and inoculum level (3–7 % v/v) on cell growth, bacteriocin production, antioxidant property, titrable acidity and pH of curd was studied by response surface methodology (RSM). The optimized conditions were 26.48 h and 2.17%v/v inoculum and the second order model validated. Co cultivation studies revealed that the formulated product had the ability to prevent growth of foodborne pathogens that affect keeping quality of the product during storage. The results indicated that application of E. faecium MTCC 5695 along with usage of optimized conditions attributed to the formation of highly consistent well set curd with bioactive and bioprotective properties. Formulated curd with potential probiotic attributes can be used as therapeutic agent for the treatment of foodborne diseases like Traveler’s diarrhea and gastroenteritis which thereby help in improvement of bowel health.

A medium using fish waste as substrate was designed for production of lipase byEnterococcus faeciumMTCC 5695 andPediococcus acidilacticiMTCC 11361. Medium components and culture conditions (fish waste protein hydrolysate (FWPH) concentration, fish waste oil (FWO) concentration, pH, temperature, and fermentation time) which affect lipase production were screened using factorial (5 factors∗2 levels) design of which FWPH concentration, FWO concentration, and fermentation time showed significance (). The levels of these factors were optimized further by Box-Behnken design using response surface methodology (RSM). Optimized conditions were found to be 5% v/v FWO, 0.15 mg/mL FWPH and 24 h of fermentation time for MTCC 5695, and 4% v/v FWO, 0.15 mg/mL FWPH and 24 h of fermentation for MTCC 11361, which were further validated. Under optimized conditions, MTCC 5695 and MTCC 11361 showed 3.15- (543.63 to 1715 U/mL) and 2.3- (214.74 to 493 U/mL) fold increase in lipase production, respectively, as compared to unoptimized conditions.