Carotenoids are considered to be important components in mango fruits. However, there is a lack of understanding about the regulation of carotenoids in mango. To gain an insight into the carotenoid metabolism pathway, carotenoid content and the expression of carotenoid metabolic genes were investigated in the peel and pulp of mango during fruit development and ripening in three cultivars, ‘Kaituk’, ‘Nam Dok Mai No.4′, and ‘Nam Dok Mai Sithong’, which are different in color. The highest carotenoid content was observed in ‘Kaituk’, followed by ‘Nam Dok Mai No.4′ and ‘Nam Dok Mai Sithong’, with the major carotenoid being β-carotene. The gene expression analysis found that carotenoid metabolism in mango fruit was primarily regulated at the transcriptional level. The changing patterns of carotenoid biosynthetic gene expression (MiPSY, MiPDS, MiZDS, MiCRTISO, MiLCYb, MiLCYe, MiHYb, and MiZEP) were similar to carotenoid accumulation, and ‘Kaituk’ exhibited a higher expression level than the other two cultivars. In addition, the differential regulation of carotenoid catabolic genes was found to be a mechanism responsible for variability in carotenoid content among the three mango cultivars. The expression of carotenoid catabolic genes (MiCCD1, MiNCED2, and MiNCED3) more rapidly decreased in ‘Kaituk’, resulting in a larger amount of carotenoids in ‘Kaituk’ than the other two cultivars.

Crude oil and natural gas are two important feedstocks for petrochemical production worldwide. At present, the domestic production of petroleum and petrochemical products (e.g. from Dung Quat and Nghi Son refineries) is not enough to satisfy the domestic demand. It is forecasted that materials such as plastics (PE, PP, PVC, ABS, PS) and rubers (SBR, NBR) will still have to be imported to meet the development of some potentially sustainable areas such as electric and electronic appliances, automotive, medicals and pharmaceuticals. In this study, petrochemical production is evaluated on the following criteria: (i) Feedstock and product market; (ii) Historical and forecasted prices; (iii) Technology evaluation, and (iv) Trend and experience on crude oil to petrochemicals. Resulting from that, some potential scenarios are proposed for petrochemical productions in Vietnam in the short-/middle- and long-term based on the imported feedstock and domestic supply.

This paper analyses the possibility for H2SO4 production using sulfur/sulfur-containing feedstocks from Dung Quat Refinery in terms of market, technology and economic efficiency. Domestic production of H2SO4 currently does not meet the domestic demand, the shortfall must therefore be compensated by imports. It is forecast that the domestic market will lack about 464 thousand tons of H2SO4 by 2025. The H2SO4 production project with a capacity of 200 thousand tons per year is proposed to go into operation in 2025. In the case of indirect production of H2SO4 from H2S rich gas through the intermediate sulfur product, the project has an estimated total investment cost of USD 143.2 million, its IRR will be around 3.2%, its NPV@13.2% will be USD 55.1 million and the total payback period will be 14 years and 4 months. In case of using H2S rich gas directly as feedstock, the project has an estimated total investment cost of USD 102.4 million, its IRR will be around 16.3%, its NPV@13.2% will be USD 15.7 million and the total payback period will be 5 years and 5 months.