The enhancement of mechanical properties of natural rubber vulcanisates was expected by surface modification of perlite particles. Thus the objective of the present study was to investigate the cure properties and the heat aging resistance properties in terms of stress at 100% elongation tensile strength and percentage elongation at break after surface modification. Furthermore the rebound resilience and abrasion resistance of perlite treated with silane filled in NR vulcanisates were investigated. In a comparison the properties of clay-filled NR vulcanisates were determined. The results reveal that surface modification by using silane caused a reduction of scorch time and cure time but an increase in torque difference and swelling resistance. Also surface modification gives better perlite-NR interactions before and after aging. The better heat resistance properties of perlite-filled NR vulcanisates than those of clay-filled vulcanisates is detected from relative property data. Nevertheless a lower percentage of rebound resilience and abrasion resistance of perlite-filled vulcanisates before and after surface modification than those of clay-filled vulcanisates are observed. This is owing to the large particle size low specific surface area poor dispersion and agglomeration of perlite in NR vulcanisates.

The potential health benefits attributed to mulberry leaf tea and its bioactive compounds such as antioxidant effects cancer chemoprevention and lower blood sugar levels have led to a huge increase of mulberry leaf tea products in the food market. The objectives of this research were to determine the appropriate amount of mulberry leaf tea powder Buri Rum 60 added in 4 snack products which were cook by 4 different process i.e. bread (baked) puifai (steam) peakpoon (stir) and snow lotus (no heat treatment). The Mulberry leaf tea powder was used in the ingredients for 3 levels i.e. 5 10 and 15%. Then the most preferred formula was analyzed for the nutritional values. The result showed that all 4 snacks added with Mulberry leaf tea powder at level of 10% were accepted the most. The nutritive value of these 4 snacks indicated that the moisture contents decreased while protein fiber ash energy increased significantly (p≤0.05). In comparison to the original formulas fat decreased significantly in bread and snow lotus added with mulberry leaf tea powder (p≤0.05) and decreased non-significantly in puifai and peakpoon added with Mulberry leaf tea powder (p>0.05). Carbohydrate increased significantly in bread and peakpoon added with mulberry leaf tea powder (p≤0.05) and increased non-significantly in puifai and snow lotus added with Mulberry leaf tea powder (p>0.05).

The objectives of this research were to characterize growth and melanin production on different culture media effect of copper ion and cobalt ion on growth and melanin production including antibacterial activity of crude melanin. The results revealed that actinomycetes strain PNST-01 have good growth on ISP-7 medium synthetic medium while strain PRBS-12 grow very well on ISP-3 medium complex medium. Both strains produced high amount of melanin showing brownish colony on ISP-7 medium but there is no melanin pigment production on ISP-1 medium and ISP-6 medium. Moreover the growth rate was reduced and both strains could not produce melanin pigment on ISP-7 medium without supplement with copper chloride and cobalt chloride. Crude melanin extract of strain PNST-01 showed antimicrobial activity against Bacillus cereus ATCC 11778 Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 25923 but could not inhibit Escherichia coli Shigella dysenteriae Salmonella typhi Klebsiella pneumoniae Serratia marcescens Pseudomonas aeruginosa and Streptococcus pyogenes . While crude melanin extract of strain PRBS-12 gave antimicrobial activity only on B. cereus ATCC 11778 and B. subtilis ATCC 6633. Based on the study the results can be used as key information for further development of melanin production and application in various industries.

The objective of this study was to construct the black pepper prices forecasting model by 4 statistical methods: Box-Jenkins method Holt’s exponential smoothing method Brown’s exponential smoothing method and damped trend exponential smoothing method. Time series of monthly black pepper prices which were gathered from the website of the Office of Agricultural Economics during January 2005 to December 2018 of 168 observations were divided into 2 datasets. The first dataset had 156 observations from January 2005 to December 2017 for constructing the forecasting models. The second dataset had 12 observations from January to December 2018 for comparing the accuracy of the forecasts via the criteria of the lowest mean absolute percentage error (MAPE) and root mean squared error (RMSE). Research findings indicated that for all forecasting methods that had been studied the most accurate method was damped trend exponential smoothing method (MAPE = 6.5773 RMSE = 10.3775)

The objective of this research was to isolate plant growth promoting rhizobacteria from Wedelia trilobata (L.) A.S. Hitchcock rhizosphere and preliminarily test their plant growth promoting properties such as nitrogen fixation siderophore production phosphate solubilization and indole-3-acetic acid production. Forty-seven bacterial isolates were obtained including 26 isolates of gram positive 18 isolates of gram negative and 3 isolates of actinobacteria. After that 8 isolates (including BWTM1_MSU BWTM2_MSU BWTM5_MSU BWTM6_MSU BWWM6_MSU BWWM8_MSU BWWM9_MSU and BWWM16_MSU) were selected for studying on root colonization and plant growth promoting properties under aseptic condition. The results showed that BWTM5_MSU had the evident on the promotion of plant growth with the most percentage of rice seed germination (63.33%) high level of root and shoot length with 6.11 cm and 3.89 cm respectively. As a result the root and shoot fresh weight was as high as 9.56 mg and 11.33 mg respectively. It also correlated with the highest production of indole-3-acetic acid up to 421.29 ug/ml. The root colonization was studied by counting rhizobacteria isolate BWTM5_MSU from rice rhizoplane and rhizosphere with presented bacterial number at 9.67x106 CFU/g root and 1.64x10 10 CFU/g soil respectively.