Assessment of Locally Available Substrates for Enhancing Sustainable Moina macrocopa Production

2026-05-19T02:37:05+00:00

Artemia is commonly used to feed fish larvae, but its high cost, specific hatching conditions, and limited local availability make it less accessible in developing countries. Moina macrocopa, a nutritionally rich and widely distributed zooplankton, offers a promising low-cost alternative, though knowledge on its large-scale production and feeding techniques remains limited. The present study was designed to evaluate the effect of different animal manures and food waste as substrates in the mass culture of Moina macrocopa, to identify the most effective and sustainable method for maximizing its production in terms of both quality and quantity. To assess the efficacy of various locally accessible substrates for the sustainable mass culture of Moina macrocopa, three laboratory experiments were carried out. Four treatments soy milk plus poultry manure, rice bran plus fish meal, cow dung plus yeast, and cow dung alone were applied to a pure culture of M. macrocopa that was fed with Chlorella sp. Moina population counts were taken every day for seven days throughout each experiment, which was conducted under controlled circumstances with constant aeration. The combination of yeast and cow dung produced the greatest average population (228.16 individuals per 600 ml) among the treatments, suggesting that this substrate is the most efficient and sustainable choice for producing Moina macrocopa on a wide scale.

Purification and Evaluation of Antimicrobial Activity and Biofilm Formation of Bacillus thuringiensis aizawai Strain HD283

2026-06-10T00:17:46+00:00

Objective: The study aimed to evaluate antimicrobial and antibiofilm activities, and purify the alkaline protease enzyme produced by Bacillus thuringiensis aizawai HD283. Methods: The experimental methodology encompassed the following steps: preparation of the inoculum, evaluate antimicrobial and antibiofilm activities, formulation of production media, enzyme activity assays, protein quantification, ammonium sulfate precipitation, acetone fractionation, and final purification using Sephadex Gel filtration chromatography. Results: After cultivating Bacillus thuringiensis aizawai HD283 under optimal environmental conditions and extracting the crude enzyme, as described in our previous research, the enzyme was subjected to the following purification steps: The purification pattern was as follow, the most active ammonium sulfate fractionation portion was at 60-75 % ammonium sulfate saturation, with 2.16 up to 2.41 % yield recovery, while the most active fraction by acetone precipitation, was wide range from 60-90 % acetone with yield recovery ranged between 13.4 to 12.0 %. Whereas, G-100 Sephadex column chromatography (final purification step) has 1.44 purification factor and 4.5 % final yield recovery of extracted enzyme.

Middle East Journal of Agriculture Research

Assessment of Locally Available Substrates for Enhancing Sustainable Moina macrocopa Production

Purification and Evaluation of Antimicrobial Activity and Biofilm Formation of Bacillus thuringiensis aizawai Strain HD283