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The aroma of fragrant rice is one of the grain quality attributes that significantly influence consumer preferences and prices in world markets. The volatile compound 2-acetyl-1-pyrroline (2AP) is recognized as a key component of the aroma in fragrant rice. The variation in grain 2AP content among various fragrant rice varieties is associated with the expression of the badh2 gene, with 19 alleles having been identified so far. The grain 2AP content is strongly influenced by environmental and management factors during cultivation as well as post-harvest conditions. This review pinpointed the major abiotic and biotic factors that control grain 2AP content. Abiotic factors refer to water, temperature, light quality, fertilizer application (both macro- and micro-nutrients), and soil properties, including salinity, while biotic factors include microorganisms that produce aromatic compounds, thus influencing the grain aroma in fragrant rice. Post-harvest management, including storage and drying conditions, can significantly impact the grain 2AP content, and proper post-harvest conditions can intensify the grain aroma. This review suggests that there are rice varieties that can serve as potential sources of genetic material for breeding rice varieties with high grain aroma content. It offers an overview of recent research on the major factors affecting the aroma content in fragrant rice. This knowledge will facilitate further research on the production of high-quality rice to meet the demands of farmers and consumers. [ABSTRACT FROM AUTHOR]

Microalgae have high potential as organisms that can be used for biodiesel production because they can accumulate high amounts of lipids in a similar manner to oleaginous plants. However, the economic feasibility of their lipid production is still in question. Possible methods of improving that feasibility involve a reduction in cultivation costs using effluents along with an increase in lipid production by co-cultivation with plant growth-supporting microorganisms. Previous studies have found that actinomycetes possess a potential as plant growth-promoters. Thus, this research study is aimed at investigating the effects of the co-cultivation of actinomycetes with microalgae on growth and lipid production in diluted chicken manure digestate. In this study, over 190 actinomycetes were screened for their ability to grow in the digestate, as well as for their plant growth promoting abilities. The actinomycete, Nocardia bhagyanarayanae I-27, could promote chlorophyll a , biomass and lipid contents in a co-culture with green microalga Tetradesmus obliquus AARL G022 in 25% diluted digestate. Microalgal major fatty acid methyl esters are a suitable substrate for biodiesel production. In addition, the essential Ω3 fatty acids, including α-linolenic acid and eicosapentaenoic acid, also increased in volume. Thus, the co-cultivation of plant growth promoting actinomycetes with microalgae in wastewater could be an alternative strategy used to increase biomass and lipid production. [ABSTRACT FROM AUTHOR]

The fermentation of steamed rice with a microbial starter yields the unique traditional alcoholic beverage known as Sato , which is widely consumed in many provinces of Thailand. Both rice variety and fermentation conditions are crucial factors in a rice-fermented beverage that contribute to the final product's quality and functionality. This study was conducted to characterize the rice-based beverage fermented from pigmented and non-pigmented glutinous rice and to optimize the bioprocess of rice-fermented beverage production. Glutinous rice varieties, including white glutinous rice, white-brown glutinous rice, germinated white-brown glutinous rice, and germinated black-brown glutinous rice, and a local microbial starter (namely, Nan starter) were used for rice-fermented beverage production through solid-state fermentation (SoSF) for 3 days and subsequently submerged fermentation (SmF) for 7 days. During the SoSF and SmF processes, key fermentation parameters, including fermentation temperature (30–40 °C) and starter dosage (0.2–1.0% w/w), were then optimized. The rice-fermented beverage produced from germinated black-brown glutinous rice had a preferable alcohol concentration (3.93%), as well as better levels of antioxidant activity (54.64%), providing a superior overall acceptable sensory characteristic compared to the rice-fermented beverage produced from non-pigmented rice. Under optimized conditions at a temperature of 30 °C and a starter dosage of 1.0%, the rice-fermented beverage had a higher antioxidant activity of 67.29% with the desired characteristics and sensory properties. This study demonstrated that the developed products might contribute to the establishment of commercially viable rice-fermented beverages with health benefits and help promote the functional food industry. • Commercially viable rice-fermented beverages with health benefits were established. • Pigmented glutinous rice-fermented beverages had great overall quality. • Pigmented glutinous rice-fermented beverages had superior antioxidant activity. • Microbial starters of 1.0% at 30 °C were suitable for the SoSF and SmF processes. • The developed rice-fermented products might promote the functional food industry. [ABSTRACT FROM AUTHOR]

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