This work aims to isolate and identify bacteria from unexplored resources in the Nasinuan Community Forest in Kantarawichai district, Maha Sarakham province, Thailand, with potential applications in agriculture. These bacteria are able to produce chitinase and phytase, besides fixing nitrogen and solubilizing phosphate. Selective media were used for screening bacteria and point inoculation was used in determining the capacity of interest in bacteria. The 16S rRNA gene sequencing was performed to identify bacterial strains. The results showed that PSB1.2.1, PSB2.1.1 and PSB3.4.3 isolates were phosphate solubilizing strains that are identified as Enterobacter hormaechei, Enterobacter sp. and Enterobacter ludwigii, respectively. PT1.1.3, as phytase-producing bacteria, showed the closest relationship to Burkholderia cenocepacia, while PT1.2.1, PT1.3.4, PT2.1.3 and PT3.3.1 are related to Burkholderia sp., Acinetobacter pittii, Bacillus cereus and Burkholderia gladioli, respectively. N1.11, N1.12, N3.3 and N3.4 are nitrogenfixing bacteria identified as Bacillus thuringiensis, Pantoea dispersa, Pantoea dispersa and Achromobacter xylosoxidans. The isolates C2.21 and C2.22 are chitinase-producing bacteria identified as Bacillus amyloliquefaciens and Bacillus amyloliquefaciens, while C2.23 was identified as Achromobacter spp. This is the first report of bacterial identification with potential agricultural application from the Nasinuan Community Forest. These bacteria may be used as bioinoculants to promote growth of local plants, enhance yields and reduce the use of chemical fertilizers.

The effects of feeding two Bacillus spp. isolated from the intestine of the giant freshwater prawn on the growth of Giant Freshwater Prawns (Macrobrachium rosenbergii de Man) was examined. The isolated Bacillus KKU02 and Bacillus KKU03 (approximately 10(7) CFU mL(-1)) were mixed into commercial prawn feed (200 mL kg(-1)). After rearing shrimp with the bacteria in four feed treatments, (Bacillus KKU03, Bacillus KKU02, mixed culture and control groups) for 120 days, body length and weight of the prawns in mixed culture tanks were significantly higher (p = 0.05) than in the control tanks (7.48 cm and 3.32 g, vs 6.6 cm and 2.1 g, respectively). Both isolates were found to produce amylase and protease. The stabilities of the single Bacillus sp., mixed culture and commercial probiotic in the feeds were examined during storage at 4 degrees C and room temperature. The percentage viability of Bacillus KKU02, Bacillus KKU03 and mixed culture stored at room temperature declined dramatically to 2.54, 21.88 and 10.92% within 2 weeks, respectively. At 4 degrees C however, the percentage viability of the tested probiotics reduced slowly. The survival of the commercial probiotics was the same at both temperatures about 50% after 70 days' storage.

Volatile compounds and antioxidant activity of kefir produced from Thai black jasmine rice (Hawm nil) were investigated and compared. Thai black jasmine rice milk was prepared by ultrasonication for 24 hours, and then subjected to nine different inoculum percentages of kefir grains and fermentation temperature conditions. Volatile compounds were detected by gas chromatography-mass spectrometry (GC-MS) analysis, while antioxidant activity was determined by DPPH free radical scavenging and ferric reducing/ antioxidant power (FRAP) assays. Metabolic pathway analysis was also conducted. Results indicated that Hawm nil rice milk kefir contained 27 volatile compounds, including four organic acids, four fatty acids, six alcohols, four esters, four ethers, three amines, one ketone and one amide. The GC-MS profile of volatile compounds differed significantly between fermentation conditions; however, antioxidant capacity of Hawm nil rice milk kefir remained constant. Metabolism of pyruvate, sulfur and glycerolipid were identified as pathways affected by fermentation. Results indicated that volatile compounds in fermented Hawm nil rice milk contributed to its antioxidant property. Varying temperature and inoculum conditions were crucial factors that affected the release of these volatile compounds. Rice milk kefir showed potential as supplementary food that was effective in ameliorating multiple human diseases and could serve as a valuable tool in promoting sustainability of human health.

In order to extend the shelf life of 2 high potential Bacillus probiotic isolates which were Bacillus KKU02 and Bacillus KKU03, the spore forms of these 2 Bacillus isolates were studied for using as probiotic instead. The low cost medium for spore production of these 2 Bacillus isolates was examined in order to produce probiotic spores for feeding the shrimps. It was found that cassava at 100 g L(-1) and supplemented with 20.0 g L(-1) dextrose, 0.1 g L(-1) MgSO4 and 2.0 g L(-1) (NH4)2SO4 showed the highest spore concentration at about 1 x 10(8) CFU mL(-1). The effects of feeding these 2 Bacillus spores on the growth of giant freshwater prawns were further examined. The spores of Bacillus KKU02 and Bacillus KKU03 (-10(7) spore mL(-1)) in pure and mixed culture forms were mixed with commercial prawn feed (200 mL kg(-1)) to give six feed treatments. Body length and weight of the prawns in mixed spore culture tanks after rearing for 90 days (13.5 cm and 59.8 g, respectively) were significantly higher (p = 0.05) than other treatments. The treated prawns were further challenged with Aeromonas hydrophila for 7 days. The percentages of survival after the challenge in the prawns fed with the mixed spores (46.8%) were also found significantly higher (p = 0.05) than others groups, except the mixed live cell treatment (60%). These results indicated that the spores of Bacillus KKU02 and Bacillus KKU03 had a high potential for using as commercial probiotics.

The objective of this study is to apply a response surface methodology in optimizing pulsed vacuum osmotic dehydration to achieve sufficient solids in a gel matrix using a diluted solution. Its application for enrichment of antioxidant compounds and nutrients is also investigated. The process variables are agar-gel bulk density (0.65-0.85 g/ml), sucrose concentration (30-60% w/w) and vacuum impregnation time (10-30 min). The results show that process variables, especially sucrose concentration, significantly affected moisture content (MC), water loss (WL) and solids gain (SG) of a model food. A quadratic model was fitted for WL, SG, weight reduction and total soluble solids prediction (). The prediction of total soluble solids was the most precise (). Optimum conditions were 32.58%w/w for sucrose content, 0.8 g/ml in bulk density and 14.34 min vacuum time. The physiological compounds can be sufficiently introduced into the model food with a diluted solution. The results may be applied to the development of new innovative products that provide the desired compound level and functionality. This will increase product value, utilization of agricultural produce, and reduce the loss of freshness in seasonal produce, especially tropical fruits.