The present study aimed to investigate the in vitro antioxidant and antimicrobial activities of hydrophilic extracts prepared from shallot and garlic bulbs, and their effects on round scad during iced storage. Both the shallot and garlic extracts exhibited antioxidant activity concerning DPPH radical scavenging, total reducing power, and lipid peroxidation inhibition. The extracts also had antimicrobial activity against both Gram-positive (Bacillus cereus, Staphylococcus aureus) and Gramnegative (Escherichia coli, Salmonella typhimurium) pathogenic strains. Effects of treatment with the extracts on quality of round scad were evaluated by monitoring the total lipid hydroperoxides (HPO), thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), total viable counts (TVC), and sensory characteristics. The spoilage indicators (HPO, TBARS, TVB-N, TVC) of the round scad treated with either shallot or garlic extracts were significantly suppressed during the ice storage period (P < 0.05). Round scad treated with either shallot or garlic extracts kept their natural sensory characteristics accepted for food-grade longer than 4 days of ice storage, compared with the control (without treatment). These results clearly show that the shallot and garlic extracts are potential natural preservatives, which can extend shelf-life of iced round scad.

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An experimental study to use a pilot vegetated submerged bed (VSB) wetland for the advanced treatment of effluent from the central wastewater treatment plant (CWWTP) of an industrial zone was carried out. The pilot VSB wetland included reeds (Phragmites australis), cattail (Typha orientalis), and blank cells in parallel. The constructed wetland was observed to be a suitable measure for wastewater reuse via the high performance of organic matter, turbidity removal, and detoxification. At loading rates of up to 250 kg chemical oxygen demand (COD) ha-1d-1, both cells with emergent plants obtained high efficiency of contaminant removal. Suspended solids (SS) and turbidity removal reached 67-86% and 69-82%, respectively. The COD removal efficiencies of the reed and cattail cells at a loading rate of 130 kg COD ha-1d-1were 47 and 55%, respectively. At a high loading of 400 kg COD ha-1d-1, the toxicity unit (TU) reduced from 32-42 to 4.9 and 4.2 in the effluent of the cattail and reed cells, respectively. Especially at loadings of 70, 130, and 185 kg COD ha-1d-1, the effluent TU was less than 3.0, corresponding to a non-toxic level to the ecosystem. The effluent quality met industrial or landscaped wastewater reuse at these loading rates.