A comparative analysis of growth kinetics, image analysis, and biofuel potential of different algal strains.

Due to the global population growth and economic development, energy demand has increased worldwide. Countries take steps to improve their alternative and renewable energy sources. Algae is one of the alternative energy sources and can be used to produce renewable biofuel. In this study, nondestructive, practical, and rapid image processing techniques were applied to determine the algal growth kinetics and biomass potential of four algal strains, including C. minutum, Chlorella sorokiniana, C. vulgaris, and S. obliquus. Laboratory experiments were conducted to determine different aspects of biomass and chlorophyll production of those algal strains. Suitable non-linear growth models, including Logistic, modified Logistic, Gompertz, and modified Gompertz models, were employed to determine the growth pattern of algae. Moreover, the methane potential of harvested biomass was calculated. The algal strains were incubated for 18 days, and the growth kinetics were determined. After the incubation, the biomass was harvested and assessed for its chemical oxygen demand content and biomethane potential. Among the tested strains, C. sorokiniana was the best in biomass productivity (111.97 ± 0.9 mg L-1d-1). The calculated vegetation indices, namely; colorimetric difference, color index vegetation, vegetative, excess green, excess green minus excess red, combination, and brown index values showed a significant correlation with biomass and chlorophyll content. Among the tested growth models, the modified Gompertz shows the best growth pattern. Further, the estimated theoretical CH4 yield was highest for C. minutum (0.98 mL g-1) compared to other tested strains. The present findings suggest that image analysis can be used as an alternative method to study the growth kinetics and biomass production potential of different algae during cultivation in wastewater.

Impact of key parameters involved with plant-microbe interaction in context to global climate change.

Anthropogenic activities have a critical influence on climate change that directly or indirectly impacts plant and microbial diversity on our planet. Due to climate change, there is an increase in the intensity and frequency of extreme environmental events such as temperature rise, drought, and precipitation. The increase in greenhouse gas emissions such as CO2, CH4, NOx, water vapor, increase in global temperature, and change in rainfall patterns have impacted soil-plant-microbe interactions, which poses a serious threat to food security. Microbes in the soil play an essential role in plants' resilience to abiotic and biotic stressors. The soil microbial communities are sensitive and responsive to these stressors. Therefore, a systemic approach to climate adaptation will be needed which acknowledges the multidimensional nature of plant-microbe-environment interactions. In the last two scores of years, there has been an enhancement in the understanding of plant's response to microbes at physiological, biochemical, and molecular levels due to the availability of techniques and tools. This review highlights some of the critical factors influencing plant-microbe interactions under stress. The association and response of microbe and plants as a result of several stresses such as temperature, salinity, metal toxicity, and greenhouse gases are also depicted. New tools to study the molecular complexity of these interactions, such as genomic and sequencing approaches, which provide researchers greater accuracy, reproducibility, and flexibility for exploring plant-microbe-environment interactions under a changing climate, are also discussed in the review, which will be helpful in the development of resistant crops/plants in present and future.

Regulation of volatile fatty acid accumulation from waste: Effect of inoculum pretreatment.

The study investigates the implications of waste feedstock, inoculum origin, and pretreatment on volatile fatty acids accumulation (VFA). The acidogenic fermentation of the feedstocks, rice mill effluent (RME), and brewery effluent (BE) was studied using untreated and pretreated (cyclic heat-acid shock) brewery anaerobic sludge as inoculum. The pretreatment was successful in refining and stabilizing VFA production from the feedstocks. The fermentation of RME with pretreated sludge had an enhanced acetate yield of 0.37 ± 0.02 mgCOD/mgCOD, even to odd ratio of 20.97 ± 0.08 mg/mg and the highest butyrate yield of 0.39 ± 0.01 mgCOD/mgCOD compared to untreated system. The pretreated system had stability in COD and pH profile, while VFA content depends on the origin of inoculum. Pretreatment inhibited the carbon sinks and augmented acetate-butyrate type metabolism with stable performance. The fermentation of RME by pretreated sludge produced a higher even-numbered VFAs and enhanced even to odd ratio in comparison with fermentation of BE, thereby affecting polymer composition and property. PRACTITIONER POINTS: The pretreated system had stable acidification, chemical oxygen demand, and pH profile. The pretreated system had higher acetate and butyrate yield compared to the untreated system. Rice mill effluent acidified with pretreated sludge had the highest even to odd ratio, 20.97 mg/mg. The even to odd ratio for acidification of brewery effluent was insignificant. Pretreatment, the origin of sludge, and the effluent had a regulatory effect on acidification.

Lingual Bracket Systems with Self Etching Primers- An In Vitro Study to Evaluate Shear Bond Strength.

AIM: To evaluate the shear bond strength of orthodontic lingual bracket systems bonded to extracted premolar teeth (Reliance self-etching primer, Clearfil Protect Bond) and self-etching primer (Clearfil SE Bond) Materials and methods: A total of 160 extracted human first premolars were selected and divided into four groups of 10 for each bracket system to be used with four different primers. Each sample was then embedded in an acrylic block, till the coronal portion. Instron testing machine model LR LOYD 50 K was used for testing the shear bond strength. RESULTS: The results obtained, suggested that all the primers had clinically acceptable shear bond strength with all the bracket system considered in the study. However, there were statistically significant differences in the shear bond strength in intergroup comparisons. CONCLUSION: The Reliance Self-Etching primer showed the highest bond strength with Alias lingual bracket system by Ormco, followed by clearfil protect bond, clearfil SE bond, and transbond, with the Alias lingual bracket system in the same order. CLINICAL SIGNIFICANCE: This study was initiated to understand the shear bond strength of self-etching primer and its efficacy over the conventional primer, which will be of use to the clinician while selecting the primer for bonding of the bracket systems and overcome debonding of brackets encountered during the treatment progress.