The Application of Microalgae an Impending Bio-Fertilizer: Maize Cultivation as a Model

The increasing demand of food crops and decrease in productivity due to continuous use of chemical fertilizer has not only resulted in decline of crop yield, loss of fertility and degradation of soil but has also led us one step back in achieving sustainable agriculture. The use of algal bio-fertilizer provides an effective, ecofriendly and non-polluting approach in improving the productivity of crop by both nitrogen fixation and photosynthesis. Algal bio-fertilizers improve soil structure and increase yield productivity even if applied in a small area. The application of algal bio-fertilizers in plants has resulted in increase in root, shoot length with number of leaves and hence overall growth of the plant has been increased. India being one of the largest producer and consumer of pulses requires abundant amount of pulse production to fulfill the demands of ever growing populations which can be achieved by using algal bio-fertilizers.Microalgae efficiently utilize and remove the nitrogen and phosphorus present in wastewater and assimilate these in valuable algal biomass. Yet, besides macronutrients such as N, P and K, microalgae also contain plant growth-promoting substances such as vitamins, carotenoids, amino acids and antifungal substances. In this study, the valorisation of microalgae as an organic slow-release fertilizer is presented.The fertilizer potential of both fresh water and marine microalgal biomass was determined; more specifically dried microalgal biomass, cultivated on microalgae in various natural and chemical methods. In the first stage the mineralization rate of both types of biomass was determined. Also a dosage toxicity test for Ca2+ and Na+ was performed using seedlings of lettuce and garden cress, respectively. Subsequently, a greenhouse maize growth experiment was performed, wherein the fertilizer potential of both types of microalgal biomass was compared with conventional inorganic and organic microalgae fertilizers. The growth rate of the maize plants and the maize yield were assessed for each fertilizer treatment, as well as the leave composition and the water, sugar and carotenoid concentrations in the maize seed. The results of the study show there was no significant difference in plant growth between the fertilizer treatments with microalgae and the conventional algae fertilizer. This demonstrates the potential of microalgae an impending fertilizer for agriculture applications.Keywords: Microalgae, Agriculture, Bio-fertilizer, Maize, Application

Culture of Efficient Marine Microalgae, Their Biochemical Composition and its Antibacterial Activity against Human Pathogens

Marine microalgae have been used for a long time as food for humans such as Chlorella vulgaris, Spirulina platensis and Nannochloropsis bacillaris and for animals in aquaculture. The biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. The three marine microalgae (Chlorella vulgaris, Spirulina platensis and Nannochloropsis bacillaris) were collected from Vellar estuary, South east coast of India. These three microalgae were cultivated in respective media (BG11, Conway, and Zarrouk) and estimated their biochemical composition (Protein content, Carbohydrate (CHO) analysis, Total lipids, Chlorophyll, Carotenoids and antibacterial activity. Simultaneously, these cultures were cultivated in flask containing 500 ml of respective media at lab condition for a period of one month and their growth, pH, biomass, CO2 fixation and carbon content were determined. Based on the growth rate, the pH of three microalgae in media was observed at lab condition. During maximum growth and biomass, the pH was found to be ranged between 9 and 11 for Spirulina platensis; 7 and 9 for Chlorella vulgaris; 8 and 9 for Nannochloropsis bacillaris. The Spirulina platensis and Chlorella vulgaris reached maximum growth rate and produced maximum biomass. Further, Chlorella vulgaris and Spirulina platensis attained maximum biomass in media at lab condition, also fixed highest level of carbon dioxide in media but they did not produce maximum biomass, though the growth of Nannochloropsis bacillaris were found high in media at lab condition. Among the three microalgae, Chlorella vulgaris and Spirulina platensis produced highest biochemical (Protein estimation) compounds. Hence, Chlorella vulgaris and Spirulina platensis were selected as efficient microalgae for antibacterial activity against human pathogen. This study revealed that certain green algae and blue green microalgae having high growth, pH, CO2 fixation, carbon content and biochemical composition paves the way for pharmaceutical activity. Antibacterial activity against human pathogen (Klebsiella pneumoniae, Proteus mirabilis, Vibrio cholera, Salmonella typhi and Escherichia coli) was evaluated.The crude and fractionated extraction of Chlorella and Spirulina were dissolved in different solvents like ethanol, methanol, chloroform and diethyl ether. The extracts were applied to 6 mm dry sterile disc in aliquots of 30 μL of solvent, allowed to dry at room temperature and placed on agar plates seeded with microorganisms. The bacteria were maintained on nutrient agar plates and incubated at 37˚ C for 24 hrs. Zones of growth inhibition were measured after incubation from all the extracts and tested twice at a concentration of 30 mg disc-1 was evaluated for Chlorella and Spirulina with their potential health benefits.Keywords: Chlorella vulgaris, Spirulina platensis, Nannochloropsis bacillaris, CO2 fixation, Biochemical composition, Pharmaceutical activit

The Application of Microalgae an Impending Bio-Fertilizer: Maize Cultivation as a Model

The increasing demand of food crops and decrease in productivity due to continuous use of chemical fertilizer has not only resulted in decline of crop yield, loss of fertility and degradation of soil but has also led us one step back in achieving sustainable agriculture. The use of algal bio-fertilizer provides an effective, ecofriendly and non-polluting approach in improving the productivity of crop by both nitrogen fixation and photosynthesis. Algal bio-fertilizers improve soil structure and increase yield productivity even if applied in a small area. The application of algal bio-fertilizers in plants has resulted in increase in root, shoot length with number of leaves and hence overall growth of the plant has been increased. India being one of the largest producer and consumer of pulses requires abundant amount of pulse production to fulfill the demands of ever growing populations which can be achieved by using algal bio-fertilizers.Microalgae efficiently utilize and remove the nitrogen and phosphorus present in wastewater and assimilate these in valuable algal biomass. Yet, besides macronutrients such as N, P and K, microalgae also contain plant growth-promoting substances such as vitamins, carotenoids, amino acids and antifungal substances. In this study, the valorisation of microalgae as an organic slow-release fertilizer is presented.The fertilizer potential of both fresh water and marine microalgal biomass was determined; more specifically dried microalgal biomass, cultivated on microalgae in various natural and chemical methods. In the first stage the mineralization rate of both types of biomass was determined. Also a dosage toxicity test for Ca2+ and Na+ was performed using seedlings of lettuce and garden cress, respectively. Subsequently, a greenhouse maize growth experiment was performed, wherein the fertilizer potential of both types of microalgal biomass was compared with conventional inorganic and organic microalgae fertilizers. The growth rate of the maize plants and the maize yield were assessed for each fertilizer treatment, as well as the leave composition and the water, sugar and carotenoid concentrations in the maize seed. The results of the study show there was no significant difference in plant growth between the fertilizer treatments with microalgae and the conventional algae fertilizer. This demonstrates the potential of microalgae an impending fertilizer for agriculture applications.Keywords: Microalgae, Agriculture, Bio-fertilizer, Maize, Application

Bacterial wilt in brinjal: Source of resistance, inheritance of resistance and molecular markers linked to resistance loci

Brinjal, eggplant or aubergine (Solanum melongena L.) belongs to the Solanaceae family and is a widely cultivated warm-season vegetable in India and around the world. Brinjal production and productivity are strongly affected by many biotic stresses, viz., fusarium wilt, verticillium wilt and small leaves of brinjal. Among all the diseases, bacterial wilt (BW) is the most destructive disease in tropical, subtropical, temperate, and humid regions worldwide due to the broad host range and prolonged duration of spore survival. BW disease in brinjal is caused by Ralstonia solanacearum, which belongs to the β-proteobacteria family and is a gram-negative, nonspore-forming, rod-shaped, and soilborne bacterium. BW disease management strategies, such as culture, mechanical, biological, and chemical methods, are ineffective due to the prolonged survival period of the bacterium in the soil and its wide host range. The use of resistant varieties and hybrids against BW disease is the safest method for controlling this disease. Information on the genetics of resistance to BW disease in brinjal is vital for the development of an effective breeding method and for identifying bacterial wilt resistance in preferable brinjal cultivars. The use of molecular markers associated with BW disease resistance gene loci helps to characterize traits of interest and develop resistant varieties and hybrids. This review described recent advances in different control measures. We focused on the importance of marker-assisted selection for identifying bacterial wilt diseases

A novel TPR-BEN domain interaction mediates PICH-BEND3 association

PICH is a DNA translocase required for the maintenance of chromosome stability in human cells. Recent data indicate that PICH co-operates with topoisomerase IIα to suppress pathological chromosome missegregation through promoting the resolution of ultra-fine anaphase bridges (UFBs). Here, we identify the BEN domain-containing protein 3 (BEND3) as an interaction partner of PICH in human cells in mitosis. We have purified full length PICH and BEND3 and shown that they exhibit a functional biochemical interaction in vitro. We demonstrate that the PICH-BEND3 interaction occurs via a novel interface between a TPR domain in PICH and a BEN domain in BEND3, and have determined the crystal structure of this TPR-BEN complex at 2.2 Å resolution. Based on the structure, we identified amino acids important for the TPR-BEN domain interaction, and for the functional interaction of the full-length proteins. Our data reveal a proposed new function for BEND3 in association with PICH, and the first example of a specific protein-protein interaction mediated by a BEN domain

Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing

No abstract available

Development of Novel Microwave Cooking Model for Not-Ready-to Eat Foods

Recently safety of microwave cooked food has come under scrutiny because of recent outbreak and recalls associated with some of these not-ready-to-eat (NRTE) frozen foods. Heating uniformity of these foods is paramount in rendering the foods safe for consumption. Degree of uneven microwave heating is influenced by both microwave oven and characteristics of food load which decides the electric field distribution within the food load. Given the complexity of parameters, a computer model is always desirable to optimize heating uniformity by proper selection of food shape, proportions, plating, packaging selection and more. Earlier many researchers have made one or more assumptions in computer model development to simplify the problem and to minimize the computational time. The main objective is to develop a holistic microwave cooking model to capture all real scenarios. Using this model, we studied the effect of microwave oven parameters as well as food load parameters. Coupled heat transfer and EM equations were solved using QWED software interfaced with Fluent software. The model was validated using 1% gellan gel temperature profile obtained by using Infrared imaging camera (SC640 FLIR) and Fiber optic sensor in both stationary and rotating turntable MW heating situation. The gellan gel as model food was useful in validating temperature profile accurately as it is possible to cut thin slices for temperature mapping of each slice. The predicted temperature profile for each layer was found to be in good agreement qualitatively and quantitatively with experimental profile. Preliminary results have hinted that irrespective of changing any parameters, non-uniform heating will remain an issue to deal with. This study increased our understanding of MW heating/cooking of heterogeneous food products and helped to optimize food parameters

Effect of Magnetron Frequency on Heating Pattern in Domestic Oven

In this study a computer model was developed to simulate microwave heating of a model food with a range of magnetron frequencies. The range was decided upon performing the frequency spectrum analysis of microwave leakage from the microwave oven. Simulation results showed that the magnetron input as sinusoidal frequency from 2.44 GHz to 2.48 GHz generates different heating profiles. The simulated heating profiles were compared with experimental heating profiles obtained by using an IR camera. None of simulations with individual frequency exactly matches with experimental temperature profile. The closet match between simulated and observed temperature profiles was found with 2.46 GHz frequency. This study helped us to understand the dynamic nature of magnetron and how it influences microwave heating pattern of any food materials

Coupled electromagnetic and heat transfer model for microwave heating in domestic ovens

Microwave ovens are used extensively for heating a variety of not-ready-to-eat food products. Non-uniform heating of foods in microwave ovens is a major concern in assuring microbiological safety of such products. The non-uniform heating of foods is attributed by complex interaction of microwaves with foods. To understand this complex interaction, a comprehensive model was developed to solve coupled electromagnetic and heat transfer equations using finite-difference time-domain based commercial software. The simulation parameters, cell size, heating time step, and number of iterations for steady state electromagnetic field were optimized. The model was validated by 30 s heating profile of a cylindrical model food (1% gellan gel) in a 700 W microwave oven. The model was validated qualitatively by comparing the simulated temperature profiles on three planes in the gel and compared them to the corresponding thermal images. Quantitative validation was performed by comparing simulated temperature of the gel at 12 locations with experimental temperature acquired at those points using fiber optic sensors. Simulated spatial temperature profiles agreed well with the thermal image profiles. The root mean square error values ranged from 0.53 to 4.52 °C, with an average value of 2.02 °C. This study laid a framework for selecting the required model parameters which are critical for better temperature prediction. The developed model can be effectively used to identify hot and cold spots in food products, thereby helping in microwaveable food product development to achieve better cooking performance in terms of heating uniformity, food quality and safety. The model can also be used to identify the best product, package and cavity parameters to achieve better heating uniformity and electromagnetic distribution inside the cavity

Heating Performance Assessment of Domestic Microwave Ovens

Due to inherent nature of standing wave patterns of microwaves inside a cavity and dielectric properties of different components in a food, microwave heating leaves non-uniform distribution of energy inside the food volumetrically. Achieving heating uniformity plays critical role in improving the safety of microwave heated products. In this paper, we present a method for assessing heating uniformity within domestic microwave ovens. A custom designed container was used to assess heating uniformity of a range of microwave ovens using IR camera. The study suggested that the best place to place food in a microwave oven is not at center but near the edge of turntable