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Exopolysaccharides (EPS) are well-known biopolymers secreted by several lactic acid bacteria with combination of various strains. The aim of this study is to increase EPS production by co-culturing Lactobacillus plantarum ATCC 8014 with Saccharomyces cerevisiae ICA-Y01 and study the changes in the functional characteristics of the EPS from both cultivations. In this study, the production and functional characteristics of EPS from co-cultivation culture of L. plantarum ATCC 8014 with S. cerevisiae ICA-Y01 were evaluated. The co-cultivation of L. plantarum ATCC 8014 with S. cerevisiae ICA-Y01was markedly increased EPS production up to 55.84% with 6.8 g/l yield after 20 hours cultivation. The pH of the co-cultivation culture was remained constantly at 5.2 until the end of cultivation. Furthermore, co-cultivation under pH 6 in the 16L bioreactor showed a higher growth rate of 0.214 h-1 and EPS production increased up to 104.44% when compared with single cultivation of L. plantarum ATCC 8014. This result clearly indicates the importance of growing the cells in the controlled pH condition when cultivated with S. cerevisiae ICA-Y01 to enhance EPS production. The functional characteristics of EPS secreted from both cultivation strategies were also evaluated. FT-IR spectroscopy confirmed EPS presence from both cultivations, indicating functional group of the polysaccharide with D-glucose units bound by α-(1→6). The EPS production from single cultivation showed a higher DPPH radical scavenging activity (88.21%) and IC50 (19.57%) as compared to EPS produced from co-cultivation with DPPH scavenging exhibited 32.45% with no IC50 value detected. Furthermore, solubility and water uptake of EPS from single cultivation are higher in comparison to co-cultivation. In conclusion, higher efficiency in the bioactivity of EPS from the single cultivation of L. plantarum ATCC 8014 was confirmed even though the EPS yield is low as compared to EPS synthesis through inter-kingdom cultivation.

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Currently, the physicochemical quality of dried chillies is becoming a characteristic of consumer choice. A study was conducted to investigate the quality of physicochemical properties of dried chillies drying by vacuum tray dryer (VTD) when compared with sun drying (SD) and freeze-drying (FD). The highest capsaicin content with the lowest moisture content was achieved when drying by the VTD technique. However, the total phenolic content and antioxidant activity are highest in dried chillies drying by FD followed by VTD. Furthermore, the physiochemical properties of dried chillies that dry under VTD technique in combination with different pre-treatment techniques were investigated to study the quality of the dried red chillies during processing and storage. The fresh chillies pretreated by hot blanching(B) gave a higher capsaicin content almost 102.9% when compared with the non-treated sample. The blanched chillies samples either by B followed by soaking in citric acid solution(B+CA) showed the lowest L* indicating richness of dark red colour of dried chillies after drying by VTD. Soaking fresh chillies in citric acid solution (CA) showed an increase of a* value (redness) to 29.00 near fresh chillies' red colour. The highest retention of capsaicin content was only for 3 months of storage when chillies were soaked in CA solution and then start to deteriorate. The combination of different pretreatment techniques of fresh chillies drying by VTD is a potential drying method due to the retention of high-bioactive contents.