The recently emerged coronavirus disease (COVID-19), which has been characterised as a pandemic by the World Health Organization (WHO), is impacting all parts of human society including agriculture, manufacturing, and tertiary sectors involving all service provision industries. This paper aims to give an overview of potential host reservoirs that could cause pandemic outbreak caused by zoonotic transmission. Amongst all, continues surveillance in slaughterhouse for possible pathogens transmission is needed to prevent next pandemic outbreak. This paper also summary the potential threats of pandemic to agriculture and aquaculture sector that control almost the total food supply chain and market. The history lesson from the past, emerging and reemerging infectious disease including the Severe Acute Respiratory Syndrome (SARS) in 2002, Influenza A H1N1 (swine flu) in 2009, Middle East Respiratory Syndrome (MERS) in 2012 and the recent COVID-19 should give us some clue to improve especially the governance to be more ready for next coming pandemic.
Algal have attracted attention from biomedical scientists as they are a valuable natural source of secondary metabolites that exhibit antioxidant activities. In this study, singlefactor experiments were conducted to investigate the best extraction conditions (ethanol concentration, solid-to-solvent ratio, extraction temperature and extraction time) in extracting antioxidant compounds and capacities from four species of seaweeds (Sargassum polycystum, Eucheuma denticulatum , Kappaphycus alvarezzi variance Buaya and Kappaphycus alvarezzi variance Giant) from Sabah. Total phenolic content (TPC) and total flavonoid content (TFC) assays were used to determine the phenolic and flavonoid concentrations, respectively, while 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picylhydrazyl (DPPH) radical scavenging capacity assays were used to evaluate the antioxidant capacities of all seaweed extracts. Results showed that extraction parameters had significant effect (p < 0.05) on the antioxidant compounds and antioxidant capacities of seaweed. Sargassum polycystum portrayed the most antioxidant compounds (37.41 ± 0.01 mg GAE/g DW and 4.54 ± 0.02 mg CE/g DW) and capacities (2.00 ± 0.01 µmol TEAC/g DW and 0.84 ± 0.01 µmol TEAC/g DW) amongst four species of seaweed. Single-factor experiments were proven as an effective tool to determine and quantify the relationship between a single factor and a single response variable.PeerJ PrePrints | https://dx.doi.org/10.7287/peerj.preprints.1249v1 | CC-BY 4.0 Open Access |
This study aimed to evaluate and compare the quality of κ-carrageenan obtained from tissue-cultured and fieldcultured Kappaphycus alvarezii. Carrageenan properties including yield, viscosity, gel strength and sulfate content were studied. After 60 days of cultivation, tissue-cultured K. alvarezii showed a higher growth rate (6.3 ± 0.01% day −1 ) than field-cultured seedlings (3.4 ± 0.3% day −1 ). The obtained carrageenan yield from tissue-cultured (67.3 ± 16.4%) was higher than field-cultured K. alvarezii (51.5 ± 21.0%). Gel viscosity of carrageenans from tissue-cultured K. alvarezii (1280.0 ± 25.0 cP) was found significantly higher than field-cultured samples (87.8 ± 20.9 cP). The 1.5% gel solution of tissue-cultured and field-cultured K. alvarezii exhibited gel strengths of 703.5 ± 14.1 and 288.3 ± 19.3 g cm −2 , respectively. The average sulfate content of carrageenans was found to be significantly different between tissue-cultured and fieldcultured K. alvarezii with 34.2 ± 10.9 and 7.5 ± 6.7%, respectively. Tissue culture is recommended to produce high quality seedlings by providing optimized culture conditions to the seaweed. This approach can serve as an alternative way to solve the seedling shortage problems currently faced by the seaweed industry.
Agrobacterium-mediated transformation for both Melastoma malabathricum and Tibouchina semidecandra were optimized using green fluorescent protein (GFP) as a reporter. The binary vector pCAMBIA1304 harboring the modified green fluorescent protein (mgfp) gene driven by the CaMV 35S promoter was used. Parameters optimized were bacterial strain, bacterial concentration, pre-culture period, co-cultivation period, immersion time, acetosyringone concentration and wounding type. Results obtained were based on the percentage of GFP expression which was observed 3 days post-transformation. Agrobacterium tumefaciens strain LBA4404 and EHA105 at concentration 1 × 107 cfu ml-1 (OD600nm 0.8) showed the highest virulence on M. malabathricum and T. semidecandra, respectively. Four days of preculture and 2 days of co-cultivation were optimum for M. malabathricum transformation, while 3 days of pre-culture and co-cultivation for T. semidecandra. Result also showed that 60 min of immersion and addition of 200 μM acetosyringone gave the highest percentage of positive transformants for both M. malabathricum and T. semidecandra. Mild wounding also significantly increased the efficiency of M. malabathricum transformation.
Seaweed farming has been identified as one of the entry point projects (EPPs) in Malaysia since the government introduced the Economic Transformation Programme, which aims to increase seaweed production to 150,000 t annually by 2020. To achieve this goal, micropropagation and subsequent acclimatization of the micropropagated seaweeds to the open sea is one of the available options to solve the seedling shortage problem. Acclimatization is an important process in which micropropagated seaweeds adjust to gradual changes in environments such as temperature, humidity, photoperiod, and pH. Success acclimatization is an important key for the seaweed tissue culture industry to move forward, and therefore, the protocol of acclimatization of micropropagated Kappaphycus alvarezii has been extensively optimized in this study.
Direct planting out of the micropropagated seaweeds to the open sea without goingthrough the nursery acclimatization phase may cause shock to the seaweeds due to sudden changes in environmental conditions. In a 2-week acclimatization study, seedlings were found to achieve optimum growth when cultivated in seawater enriched with mixed-algae fertilizer, natural seaweed extract (NSE), under a regimen of daily medium change and culture density of 0.40 g L −1 . The acclimatized K. alvarezii has achieved 83.33 ± 5.77 % of survival in the seaweed farm with normal physiology and no epiphyte coverage. This study has provided useful information for seaweed cultivators to enhance the survival rate of micropropagated K. alvarezii through nursery acclimatization prior to serve as seedlings for commercial seaweed cultivation.
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