Two-year surveillance of tilapia lake virus (TiLV) reveals its wide circulation in tilapia farms and hatcheries from multiple districts of Bangladesh

Tilapia lake virus (TiLV) is an emerging pathogen in aquaculture, reportedly affecting farmed tilapia in 16 countries across multiple continents. Following an early warning in 2017 that TiLV might be widespread, we executed a surveillance programme on tilapia grow-out farms and hatcheries from 10 districts of Bangladesh in 2017 and 2019. Among farms experiencing unusual mortality, eight out of 11 farms tested positive for TiLV in 2017, and two out of seven tested positive in 2019. Investigation of asymptomatic broodstock collected from 16 tilapia hatcheries revealed that six hatcheries tested positive for TiLV. Representative samples subjected to histopathology confirmed pathognomonic lesions of syncytial hepatitis. We recovered three complete genomes of TiLV from infected fish, one from 2017 and two from 2019. Phylogenetic analyses based on both the concatenated coding sequences of 10 segments and only segment 1 consistently revealed that Bangladeshi TiLV isolates formed a unique cluster within Thai clade, suggesting a close genetic relation. In summary, this study revealed the circulation of TiLV in 10 farms and six hatcheries located in eight districts of Bangladesh. We recommend continuing TiLV-targeted surveillance efforts to identify contaminated sources to minimize the countrywide spread and severity of TiLV infection.     

Agrobacterium-mediated transformation of the CrDAT gene and selection of transgenic periwinkle lines with a high vincristine accumulation

Catharanthus roseus contains vincristine and vinblastine, which are outstanding drugs for cancer. In the biosynthetic pathways of terpenoid indole alkaloids (TIAs) in C. roseus, deacetylvindoline 4-O-acetyltransferase (DAT) is a key enzyme that catalyses the last reaction of vindoline biosynthesis to form vinblastine and vincristine. In this study, the CrDAT transgene was transferred into the periwinkle by Agrobacterium-mediated transformation and generated transgenic periwinkle lines with an increase in vincristine accumulation. The C. roseus DAT gene was introduced into C. roseus plants and it was confirmed that CrDAT was successfully transferred into the genome of periwinkle plants and efficiently translated to synthesise recombinant DAT protein. Four transgenic periwinkle lines in T1 generation, T1-1, T1-3, T1-6, and T1-7, expressed recombinant DAT protein with the total protein content in the range of 2.86 μg.mg^?1 to 5.12 μg.mg^?1. Moreover, the vincristine contents of four transgenic lines increased by 1.63?2.48-fold compared to non-transgenic plants, ranging from 6.91 µg.g^?1 (fresh weight) to 10.53 µg.g^?1 (fresh weight). The T1-1 line had the highest vincristine content. Hence, the overexpression of the recombinant DAT protein can improve the vincristine accumulation of transgenic C. roseus plants.

Abbreviation: CrDAT - Catharanthus roseus Deacetylvindoline-4-O-Acetyl Transferase; D4H - Deacetoxyvindoline 4-hydroxylase; ELISA - Enzyme-Linked Immunosorbent Assay Monoterpene indole alkaloid; T0, T1 - Generations of transgenic plants; TIAs - Terpenoid indole alkaloids; WT- The wild-type tobacco plants (non transgenic plant); 35S - Cauliflower mosaic virus 35S promoter     

Comparative energy and economic analyses of conventional and System of Rice Intensification (SRI) methods of rice production in Thai Nguyen Province,Vietnam

The consumption of energy inputs in agricultural production has been increasing rapidly during the past decades. However, given the limitations and costs of non-renewable energy, increasing production while using the least energy possible has become a major concern of most nations. Prompted by this concern, we conducted a face-to-face survey of 90 farming households in Thai Nguyen Province, Vietnam, to find out how energy is being used in agriculture and, specifically, in their rice production. Through analysis of energy input–output balances, combined with economic efficiency analysis, a comparison was made of conventional and SRI methods of rice production. The study found that applying the SRI method can save around 23% of energy inputs, while increasing energy outputs by 11%. Economic benefits per hectare also rise by more than 8 million dong (USD 364) compared to those under the conventional cultivation system. The study also showed conflicts between the energy and economic balances for manual compared with machine ploughing operations. This study contributes to providing an overview of energy consumption in rice cultivation at the household level. Its findings can help stakeholders to assess current policies and make better decisions on the uses of energy in agricultural production. In addition, the comprehensive approach taken here to analysing energy use and efficiency could expand the analysis and comparison of energy uses at sectoral or activity level—still a new field in Vietnam and many other countries.     

A study of experimental autoimmune encephalomyelitis in dogs as a disease model for canine necrotizing encephalitis

In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund''s complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs.     

Productivity of Sargassum linearifolium in potassium fortified inland saline water under laboratory conditions

Growing aquatic species in inland saline water (ISW) is one way to reduce the adverse impact of ISW to agriculture farms. This 84‐day laboratory‐trial was conducted to study the growth of Sargassum linearifolium cultured in ocean water (OW), ISW, ISW fortified with potassium equivalent to 100% (ISW100), 66% (ISW66) and 33% (ISW33) of potassium in OW at 35 g/L. The biomass and cumulative specific growth rate (SGR) of S. linearifolium increased significantly (p < .05) with increased potassium in ISW until 56 days and then declined. The ISW100 and OW resulted in similar growth patterns and yielded peak biomass at day 42, proving static biomass for the next 28 days before declining. The biomass of S. linearifolium cultured in ISW and ISW33 significantly (p < .05) decreased and was lower than in ISW100 and died after day 56. The SGR of S. linearifolium in OW, ISW100 and ISW66 levelled off and showed no difference during the first 56 days. The S. linearifolium biomass and SGR negatively and significantly (p < .05) correlated with the concentrations of nitrate, phosphate in all waters. The increased potassium concentration in ISW similar to its concentration in SW brought the growth of S. linearifolium cultured to a level that was similar in OW.     

The grafting of recycled polyol from waste polyurethane foam onto new polyurethane and its impact on shape recovery and water vapor permeation

Recycled polyols from waste polyurethane (PU) foams were grafted onto PU to improve the properties such as tensile strength, shape recovery, low-temperature flexibility, and water compatibility. The recycled polyol was either purified by column chromatography before grafting or was used directly for grafting. The soft segment melting temperature of PU did not notably increase with the addition of polyol, whereas the glass transition temperature increased with increased polyol content. The tensile strength sharply increased at low polyol content and decreased at high polyol content, while the strain at break did not significantly change with an increase in polyol content. The shape recovery at 10 oC notably improved compared with unmodified PU and remained high after four cyclic tests. Polyol-grafted PU demonstrated better lowtemperature flexibility and reduced the water vapor permeability of PU membranes. Overall, grafting recycled polyol onto PU significantly improved the tensile stress, shape recovery, and low-temperature flexibility of PU.     

Effects of Fermentation Conditions Using Lactobacillus plantarum on the Charantin,Stigmasterol Glucoside and β-sitosterol Glucoside Contents of Bitter Gourd (Momordica charantia L.) Juice

Plant Foods for Human Nutrition - Bitter gourd fruits contain high amounts of charantin, stigmasterol glucoside and β-sitosterol glucoside, which have been shown to provide health benefits for...     

Blood and liver biopsy for the non‐destructive screening of tilapia lake virus

Detection of tilapia lake virus (TiLV) in tilapines is mainly from visceral organs of killed fish. However, lethal sampling might not be viable to broodstock and economically important ornamental cichlids. To contribute towards screening of the virus in asymptomatic infected fish, a subclinically infected population of Nile tilapia adults obtained from a local farm was preliminarily tested to compare different non‐lethal sampling methods, for example liver biopsy, gill biopsy, fin clip, mucus, faeces and blood for detection of TiLV. Only liver and blood samples gave positive results by PCR. Since blood sampling is relatively simpler, it was further used for five naturally co‐cultured juvenile fish species from above‐mentioned farm including 40 red tilapia broodstock and 20 Nile tilapia adults from two other different farms. The results showed that from the tested fish, 4 of 5 Nile tilapia, 2 of 5 hybrid red tilapia and 3 of 5 giant gourami blood samples tested positive, while 38 of 40 blood samples of red tilapia tested positive for TiLV in second‐step PCR. Sequencing representative PCR amplicons of positive samples confirmed sequence identity to TiLV. In conclusion, both blood and liver biopsy are practical non‐destructive sampling platforms for TiLV screening in cichlids with blood being more convenient, especially for tilapia broodstock.     

Lipoxygenase inhibitory activity of anacardic acids

6[8'(Z)-pentadecenyl]salicylic acid, otherwise known as anacardic acid (C15:1), inhibited the linoleic acid peroxidation catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, type 1) with an IC50 of 6.8 microM. The inhibition of the enzyme by anacardic acid (C15:1) is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Dixon plots indicates that anacardic acid (C15:1) is a competitive inhibitor and the inhibition constant, KI, was obtained as 2.8 microM. Although anacardic acid (C15:1) inhibited the linoleic acid peroxidation without being oxidized, 6[8'(Z),11'(Z)-pentadecadienyl]salicylic acid, otherwise known as anacardic acid (C15:2), was dioxygenated at low concentrations as a substrate. In addition, anacardic acid (C15:2) was also found to exhibit time-dependent inhibition of lipoxygenase-1. The alk(en)yl side chain of anacardic acids is essential to elicit the inhibitory activity. However, the hydrophobic interaction alone is not enough because cardanol (C15:1), which possesses the same side chain as anacardic acid (C15:1), acted neither as a substrate nor as an inhibitor.     

Effect of far-infrared radiation on the antioxidant activity of rice hulls

After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.