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Purpose Thailand generates approximately 18 million tons of urban food waste per year, which is disposed of with municipal waste and largely goes to landfills. However, this approach not only takes up a large area but also causes environmental problems. The easiest way to manage food waste is by separating it at the source and composting it. Bioaxel Co., Ltd. has developed an innovative approach for composting food waste, with the output commercially marketed as “BA compost”. However, the use of BA compost has not been independently studied.Methods BA compost was mixed with soil in various proportions (0% - 70% v/v) for planting lettuce to find the proper BA proportion. Growth characteristics and nutrient contents were investigated.Results The BA compost improved the soil nutrients. 10% BA compost in soil gave the highest growth parameters among the proportions tested, with the highest root length (21.83 ± 0.83 cm), plant length (30.00 ± 1.00 cm), number of leaves (23.33 ± 1.15 leaves), thickness (12.47 ± 0.57 mm), width of bush (26.33 ± 0.58 mm), fresh plant weight (113.03 ± 1.28 g), dry plant weight (4.58 ± 0.14 g), chlorophyll a and b (0.38 and 0.38 mg/mL), carotenoid (155.28 mg/mL), protein (443.38 μg/mL), carbohydrate (4,321.31 μg/mL) and reducing sugar (683.33 μg/mL).Conclusion BA compost from food waste demonstrated its potential in sustainable food waste management and could be used as a fertilizer. It supports an environmentally closed-loop approach to return the food waste back to the source as plant food.

A crucial property of fibrous packaging paper for food is water resistance, while strength properties are also important. To improve these properties, several bio-coating solutions were applied as coatings on paper made of pineapple leaf pulp. The effects of beeswax, chitosan, shellac, alginate/gellan gum and beeswax–chitosan (1% chitosan+4%glycerol+30%beeswax) solutions on pineapple leaf pulp paper were assessed in relation to making biodegradable paper plates. The cooking time (120–180 min) of chemical pulping and the dose of pulp by moist weight (200, 250, and 300 g) to a paper frame (40 × 40 cm2) were also studied on making the paper samples. The papers were tested for their physical and mechanical properties. The optimal cooking time and dose of pulp by moist weight found were 180 min and 300 g of pulp per frame, respectively. The bio-coatings increased average grammage and thickness of paper, but gave density reduction from that of uncoated paper. Coating paper with beeswax–chitosan solution gave the longest absorbency time, followed in rank order by alginate/gellan gum, chitosan, beeswax and shellac. The maximum 5.9 kN/m2 tensile strength was found for paper coated with beeswax–chitosan solution before hot pressing. On comparing papers bio-coated before or after hot pressing, no difference was found in the degradable time with NaAlg/gellan coating, while such difference was observed with beeswax-chitosan coating. The results suggest beeswax–chitosan solution as the best among the alternatives tested, for coating paper to make biodegradable plates.

Research background. Lovastatin is a well-known drug used to reduce hypercholesterolaemia. However, the cost of lovastatin production is still high. Therefore, alternative low-cost carbon sources for the production of lovastatin are desirable. Experimental approach. Four different agricultural wastes, namely corn trunks, rice husks, wild sugarcane, and soya bean sludge, were tested separately as substrates to produce lovastatin using a new fungal strain, Aspergillus sclerotiorum PSU-RSPG 178, under both submerged and solid-state fermentation (SSF). Results and conclusions. Of these substrates and cultivation systems, soya bean sludge gave the highest lovastatin yield on dry mass basis of 0.04 mg/g after 14 days of SSF at 25 °C. Therefore, the soya bean sludge was separately supplemented with glucose, wheat flour, trace elements, palm oil, urea and molasses. The addition of the palm oil enhanced the lovastatin yield to 0.99 mg/g. In addition, the optimum conditions, which gave a lovastatin yield of (20±2) mg/g after 18 days of SSF, were soya bean sludge containing 80 % moisture (dry basis) at a ratio of soya bean sludge (g) to mycelial agar plugs of 1:4, and a ratio of soya bean sludge (g) to palm oil (mL) of 1:2. Besides, the lovastatin yields obtained from SSF using fresh or dry soya bean sludge were not significantly different. Novelty and scientific contribution. We conclude that A. sclerotiorum PSU-RSPG 178 has a good potential as an alternative strain for producing lovastatin using soya bean sludge supplemented with palm oil as a carbon source.

Many factors affect the growth performance of microalgae, especially culture medium impacts growth rate and fatty acid composition. Thus, the aims of this study were to investigate the effects of various culture media including NSIII, Chu No.10, BG11 and BBM on the growth kinetics, biomass productivity, lipid content, lipid productivity and fatty acid profiles of cultivated Chlorella sp.T12. The Chlorella sp.T12 was cultured at 25±2 ºC temperature under continuous 3,500 Lux light intensity for 14 days. The culture in BBM medium allowed the highest of the specific growth rate (0.83±0.69 d-1 ), biomass productivity (0.20±0.05 g/l/d), lipid content of the dry weight (14.434%) and lipid productivity (0.029±0.01 g/l/d) and percentage of unsaturated fatty acid (67.56%). The unsaturated fatty acid meet requirement of fatty acid composition that suitable for biodiesel production. Although, the lipid content of cultivation in NSIII was the lowest, the percentage of saturated fatty acid (51.88%) was the highest that suitable for pharmaceutical and cosmetic production. Therefore, the BBM was the best medium choice for cultivating Chlorella sp.T12 to provide high productivity of biomass and lipids that can be used in biodiesel. NSIII was the best medium choice for cultivating Chlorella sp.T12 for pharmaceutical and cosmetic production.

Natural rubber harvested from the rubber tree is one of the most economically important agricultural products for Thailand. Factories using primary rubber products especially rubber sheets and block rubber encounter problems associated with fungal growth and often receive public complaints about the malodor they generate as well as other environmental concerns. In this study, the use of wood vinegar produced from rubber wood to ameliorate these problems was investigated. Its efficiency as an antifungal agent was determined from the number of counts of fungal colonies formed per cm2 and per gram of material, on rubber sheets and block rubber respectively. To analyze the effect of wood vinegar on malodor from block rubber processing, shredded rubber samples were prepared and the organic acids contained in the gas released during the rubber drying process were measured. The results showed that wood vinegar can significantly decrease the numbers of fungal colonies on rubber sheets and shredded rubber. A 5.0% application of wood vinegar which reduced fungal growth during the storage of shredded rubber also reduced the malodor from the drying process. The ability of wood vinegar to reduce fungi and the organic acid content of the air released during the rubber drying process is due to the presence of phenolic compounds and acetic acid. Thus soaking in wood vinegar is an effective way to deal with these problems and shows a very high potential to do so without any significant toxicity.

The utilization of wastes from concentrated rubber latex industry for composting is promising as a sustainable and environmentally friendly method.The aim of this study was to utilize wastes including skim latex serum (SS) and concentrated latex sludge (CS) as a raw composting ingredient after being combined with para rubber wood sawdust (SD) at a ratio of SS, CS, and SD of 1:1:1.Effective microorganisms, pig manure and chicken manure were used as natural activator sand were added to the composted materials at ratios of 10, 20, and 30 wt%.The best activator for composting was found to be PM added at a ratio of 10 wt% after a composting time of 25 days.The growth of Chinese kale after application of this compost to which chitosan had been added produced a much higher yield of fresh weight than those was achieved using commercial compost. Thus, compost from waste materials produced from the rubber latex industry could be employed in conjunction with chitosan to promote better agricultural growth, and logically should contribute to cost saving in the latex industry as well as aiding its waste disposal.