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Volume 5, Issue 1 (6-2016)
Abstract
Solvent extraction and taguchi method were used to optimize conditions for the antioxidant activity of Azolla fern extracts. The independent processing variables were ethanol concentration, extraction time and solid to solvent ratio. Ethanol concentration and solvent to solid ratio significantly affected antioxidant activity measured by the total phenol content (p < 0.05). whereas the extraction time did not significantly affect the activity (p > 0.05). Antioxidant activity of the extracts, determined by the total phenolic content, varied from 5.77 to 16.42 mg acid gallic equivalents/g of dry sample. DPPH scavenging activity percentage ranged from %20.51 to %93.71. Ethanol concentration of %50 and sample to solvent ratio of 1 to 15 were optimal for the highest antioxidant activities measured by the TPC assay and the DPPH method. The optimal extraction time was 48h. The result show that azolla fern is suitable for antioxidant extraction.
Mohammad Mohammadi, Habib Sarsangi Aliabad, Nasrin Mashaii, Ahmad Bitaraf, Farhad Rajabipour, Mahmoud Hafeziyeh,
Volume 6, Issue 2 (9-2017)
Abstract
Growth indices (WG and SGR), food (FCR) and protein efficiency (PER and PCE) of fingerling Nile tilapia, Oreochromis niloticus,were evaluated in 3 synchronous examinations with 12 treatments in triplicates. Groups of control, canola meal (at rates of 25, 50, 75 and 100%), cottonseed meal (at rates of 15, 25, 35 and 45%), as the replacements of expensive protein sources (fish meal and soybean meal), and azolla (at rates of 13, 21 and 29% of diet) were studied. Growth indices, total food intake and protein intake of the control were the highest of all. They decreased with increase in plant protein in every group (p<0.05). FCR and protein efficiency indices didn’t show significant differences (p>0.05) between control and canola meal (at rates of 25 and 50%), cottonseed meal (at rates of 15, 25 and 35%) and azolla (at rates of 13 and 21%). Total food intake, protein consumption and growth indices decreased, because all plant protein ingredients were unpalatable. If the problem of palatability is solved, it seems that the expensive protein sources replace with canola meal and cottonseed meal at the rates of 50 and 35% respectively, and azolla can be used at the rate of 21% in diets.
Volume 7, Issue 2 (7-2018)
Abstract
The water fern weevil, Stenopelmus rufinasus Gyllenhal (Coleoptera: Curculionidae), is considered as the most important biological control agent of Azolla spp. in the world. Azolla spp. was introduced in Iran in 1986. In August 2017, two specimens of S. rufinasus were collected on Azolla spp. in waterways near Anzali lagoon and Rice Research Institute of Iran (RRII) in Guilan province for the first time. Identification was based on molecular sequencing. This is the first record of S. rufinasus from Iran.
Volume 12, Issue 1 (2-2023)
Abstract
Diasemiopsis ramburialis and Nomophila noctuella are moths from Spilomelinae (Lepidoptera: Crambidae) with an overlapping feeding period on Azolla spp. in northern Iran. Due to some morphological similarities, immature stages often lead to confusion. A five-year study conducted in laboratory and natural environments revealed that, despite these morphological similarities, distinct characteristics in both morphology and behavior can facilitate their primary identification in the field. Diasemiopsis ramburialis eggs, and first instar larvae are opaque to pale orange, while those of N. noctuella are pale to creamy. Additionally, the last instar larvae of D. ramburialis feature orange head capsules with smaller body sizes and tend to pupate near the feeding site. In contrast, Nomophila noctuella's last instar larvae have black head capsules, larger body sizes, and pupate at a distance from the feeding site. Both species exhibit shelter-building behavior, binding Azolla spp. leaves together using silken webs to create protective enclosures. However, D. ramburialis larvae construct more robust shelters and produce more webs. They primarily remain within these shelters and navigate through web-formed corridors. On the other hand, N. noctuella larvae prefer to move along the feeding site margins within corridors formed by bound-up leaves and display a more wandering behavior. The study's findings indicate that Azolla spp. serves as the primary host plant for D. ramburialis, while N. noctuella appears to choose its host plants randomly.
