Evaluation of Ecotoxicity of Nanoceria to Organisms of Different Trophic Levels

he present study was aimed at evaluation of the toxicity potential of nanoceria on phosphobacteria (Bacillus megaterium ; soil ecosystem), azolla (Anabaena azollae and microalgae ; Aquatic ecosystem) and sorghum (Sorghum bicolor (L.) Moench) pollen grain and photosystem (PS) II quantum yield (terrestrial ecosystem). The study examined the differences in toxicity among a different concentration of nanoceria to each organism and differences in toxicity among the organisms. In each toxicity experiment, the concentration of nanoceria used are 0, 5, 10, 25, 50, 100, 200, 400, 500, and 1000 mg L-1. The result indicated that nanoceria is not toxic to soil microbes, aquatic organisms and terrestrial plants at lower concentration (up to 25 mg L-1). However, above 25 mg L-1 concentration, differential responses between nanoceria and organisms were observed. Higher concentration (500 and 1000 mg L-1) inhibited the growth of phosphobacteria, microalgae, and pollen germination and PS II quantum yield. The adverse effect caused by nanoceria could be associated with the concentration of nanoceria, differences in interactions with the cell with nanoceria, and oxidative damage caused by nanoceria. Among the assays, pollen germination was found to be more sensitive to the nanoceria in the medium, followed by photosystem II quantum yield.

UJI PENGARUH TEPUNG AZOLLA (Anabaena azollae) DENGAN TAKARAN YANG BERBEDA PADA PAKAN TERHADAP PERTUMBUHAN DAN KELANGSUNGAN HIDUP IKAN NILA SRIKANDI (Oreochromis niloticus)

This study was conducted to determine the effect of the provision of azolla flour into pellet feed to improve the performance of tilapia. This study used a complete randomized block (CRD) consisting of 4 treatments and 3 replications with doses, namely: (K - 100% pellet feed), (A - 75% + 25% Azolla pellet), (B – pellet 50% + 50 % Azolla), (C - pellet 25% + 75% Azolla) main parameters include weight growth, survival and feed conversion ratio (FCR), feed utilization efficiency (EPP). While supporting parameters include temperature, pH, DO. Then the data obtained was processed dst and analyzed using excel, analysis of variance (ANOVA) with a confidence of 95% and continued using BNT test. If there was a significant effect on the treatment. The ANOVA test results showed that the administration of azolla flour on feed did not have a significant effect on absolute growth and daily growth rate, survival FCR, and efficiency of feed utilization (EPP) of tilapia (p<0.05), thus the results of the study could be concluded the addition of azolla flour to tilapia feed in this study did not have a significant effect, so there was no need to do further tests on BNT0.05 (Smallest Significant Difference). The results in this study on absolute growth control treatment amounted to 0.83 gram, specific growth rate of 0.69%, FCR of 1.72, survival (SR) of 53% while feed utilization efficiency (EPP) of 43.82% no one has a real influence.

The Study on the Cultivable Microbiome of the Aquatic Fern Azolla Filiculoides L. as New Source of Beneficial Microorganisms

The aim of the study was to determine the still not completely described microbiome associated with the aquatic fern Azolla filiculoides. During the experiment, 58 microbial isolates (43 epiphytes and 15 endophytes) with different morphologies were obtained. We successfully identified 85% of microorganisms and assigned them to 9 bacterial genera: Achromobacter, Bacillus, Microbacterium, Delftia, Agrobacterium, and Alcaligenes (epiphytes) as well as Bacillus, Staphylococcus, Micrococcus, and Acinetobacter (endophytes). We also studied an A. filiculoides cyanobiont originally classified as Anabaena azollae; however, the analysis of its morphological traits suggests that this should be renamed as Trichormus azollae. Finally, the potential of the representatives of the identified microbial genera to synthesize plant growth-promoting substances such as indole-3-acetic acid (IAA), cellulase and protease enzymes, siderophores and phosphorus (P) and their potential of utilization thereof were checked. Delftia sp. AzoEpi7 was the only one from all the identified genera exhibiting the ability to synthesize all the studied growth promoters; thus, it was recommended as the most beneficial bacteria in the studied microbiome. The other three potentially advantageous isolates (Micrococcus sp. AzoEndo14, Agrobacterium sp. AzoEpi25 and Bacillus sp. AzoEndo3) displayed 5 parameters: IAA (excluding Bacillus sp. AzoEndo3), cellulase, protease, siderophores (excluding Micrococcus sp. AzoEndo14), as well as mineralization and solubilization of P (excluding Agrobacterium sp. AzoEpi25).

Pengaruh Konsentrasi Pupuk Azolla pinata Terhadap Pertumbuhan Populasi Spirulina platensis [The Effect Of Azolla pinata Fertilizer Concentration In Spirulina platensis Population Growth ]

Spirulina merupakan salah satu jenis alga yang sangat diminati oleh produsen pembenihan dan suplemen kesehatan. Hal yang dapat mendorong peningkatan produksi Spirulina adalah peningkatkan pertumbuhan, yaitu meningkatkan jumlah sel. Salah satu cara untuk meningkatkan pertumbuhan fitoplankton adalah mengontrol kandungan nutrien baik makro maupun mikro pada lingkungan budidaya. Azolla pinata memiliki berbagai unsur hara antara lain N, P, K, Ca, S, Mg, Mn, Fe, Zn, Co. Kandungan unsur kimia dalam Azolla pinata secara kualitatif dan kuantitatif dapat memenuhi kebutuhan unsur makro dan mikro pertumbuhan Spirulina platensis. Azolla pinata merupakan tanaman paku mini yang bersimbiosis dengan cyanobacteria pemfiksasi N2 yaitu Anabaena azollae. Simbiosis ini menyebabkan Azolla pinata sebagai sumber N. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh konsentrasi pupuk Azolla pinata terhadap pertumbuhan populasi Spirulina platensis dan untuk mengetahui konsentrasi optimal pupuk Azolla pinata yang dapat menghasilkan pertumbuhan tertinggi Spirulina platensis. Penelitian dilaksanakan di Fakultas Perikanan dan Kelautan Universitas Airlangga Surabaya. Rancangan penelitian yang digunakan adalah Rancangan Acak Lengkap (RAL) dilanjutkan dengan uji jarak berganda Duncan. Bahan uji yang digunakan dalam penelitian ini adalah S. platensis yang dikultur pada botol kaca 500 ml dengan lima perlakuan dan empat kali ulangan. Bahan pupuk yang digunakan adalah 500 gram Azolla pinata dan 2 liter aquades. Konsentrasi pupuk Azolla pinata yang diberikan pada perlakuan adalah A (3,5 ml), B (5,5 ml), C (7,5 ml), D (9,5 ml), E (kontrol Walne 1 ml). Parameter utama yang diamati adalah populasi, sedangkan parameter pendukung yang diamati adalah suhu, pH, dan salinitas. Hasil penelitian menunjukkan bahwa konsentrasi pupuk Azolla pinata memberikan pengaruh yang berbeda nyata terhadap pertumbuhan populasi Spirulina platensis. Penambahan pupuk Azolla pinata kedalam media kultur menggunakan konsentrasi 3,5 ml menghasilkan populasi Spirulina platensis tertinggi sebesar 1708,6 x 103 unit/ml.

Potential of Anabaena Azollae Extract as Antimicrobial Agent For Paddy Crop Disease

The research objective was to test antimicrobial activity from compound produced by A. azollae which symbiosis with Azolla sp. toward microbial test of X. oryzae and Pyricularia oryzae as cause of disease on paddy crop. Sampling of Azolla which symbiosis with A. azollae was done in Azolla cultivation pond at Faculty of Agriculture, Sriwijaya University. The available Azolla was consisted of two types, i.e. Azolla pinnata and Azolla mycrophiylla. The extraction of A. azollae from Azolla leaves was done by method of Ultrasound Assisted Extraction (UAE) using ethyl ester solvent and maseration method using methanol solvent. Test media for bacteria and fungus respectively are Mueller Hilton Agar (MHA) and Sabouraud Dextrose Agar (SDA). The diameter of produced clear zone is an indication of extract’s inhibitory power toward bacteria or fungus. The different of inhibitory zone diameter is compared by using t-test. Analysis of active compounds on Anabaena azollae extract was done by using HPLC. Ethyl acetate or methanol extract of A. azollae which symbiosis with A. pinnata or A. microphylla was capable to inhibit the growth of X. oryzae bacterium and P. oryzae fungus. The dominant compounds containing within extract with probability more than 60% and area of more than 10% are consisted of phytol, hexadecanoate acid and 2-(tert-butyl)-4,6-dimethyl phenol.