Garlic is an ancient food and medicinal plant that has been used for centuries. The research team was interested in creating a garlic oil extract that could help reduce microbial contamination in the air during the prolonged period of the COVID-19 situation. A prototype sugarcane leaf paper filter was treated with garlic oil extract to improve its air purification properties and to reduce the number of microorganisms. This study investigated garlic oil extracts that were produced by a garlic fermentation process with isolated lactic acid bacteria. The oil was then extracted using steam distillation or maceration with 80% ethyl alcohol. Both these methods demonstrated that they were effective in inhibiting pathogenic microorganisms contaminating isolated from air (Fungi: Penicillium sp. Aspergillus spp. and Rhizopus sp. and Bacteria: E. coil Bacillus subtilis and Staphylococcus sp.) by Agar Diffusion method. It was found that the garlic oil extract distilled from steam was the best choice for further development as a coating for filter paper. Garlic oil extract can be stored at room temperature for at least 15 days after being coated on filter papers. After that the filters with garlic extract-coated filters made by sewing together four folded filter papers could remove the dust of 2.5 sizes as well as HEPA filters but had a disadvantage in filtering dust that was at least 10 PPM. This paper filter prototype was environmentally friendly because it could decompose on the ground within 12-15 days and reduce the spread of infection problems. From overall the prototype of the garlic oil extraction process can be developed at a commercial industrial level to produce large quantities of garlic extract with desired quality tracking features. It helps reducing environmental problems in a sustainable way; reducing waste conserving energy and using environmentally friendly materials.

The research team has isolated the cellulase producing microorganisms which have capability in producing extracellular cellulase enzyme for cellulosic degradation from leftover agricultural waste materials such as fruits and vegetables. After cellulosic material degradation the products mainly were sugar moiety being the starting materials for further alcohol fermentation and/or possibly being used in cultivation of common microorganisms. In the study when different 49 bacterial isolates were tested for their cellulase activity on Carboxymethyl cellulose (CMC) two bacteria Bacillus spp. CE08 and 49 were selected due to high cellulase activity and thus tested for the physical and chemical properties. Their 16S rDNA sequence comparisons were close to Bacillus sp. isolate obtained from the soil. Both isolates are common aerobic/facultative aerobic bacteria with the length of 1-3 μm Gram positive and preferring the fermentation of maltose and xylose to glucose while minimal degradation on sucrose and lactose contents. Their optimum digestibility was at 40°C pH 4.5 for the broth having unpurified extracellular cellulase activity at 3-4 μg /mg. The enzyme could use the substrateCMC the best but rice straw more slowly but better than grass. However the enzyme displayed the least digestion effectiveness on cotton. Both of these isolates are expectedly applied in the biological degradation process substituting chemicals that cause pollution problems to the environment. Additionally this is one promise way to bring value of agricultural waste to the community.

The study is the development of biological methods for extracting gold from the effluents of the gold processing and gold extraction in the industries where has a very high acidity (pH 0-4). This method should be used to replace the electrochemical process and chemical method which cause the pollution of toxic substances acid fumes and heavy metals of copper cyanide to the environments. The research started at the characterization and identification of microorganisms presented in gold contaminated water in natural source where is highly acidic (pH 2-4) and it could synthesize nanogold particles. The bacteria Bacillus sp. E201 were identified from this source and it showed its 16S rDNA gene with similarity of 95% to bacteria Bacillus thuringiensis accession no. FJ755916. It could create gold in the solution outside the cells within three days Form 1 mM HAuCl4 • 3H2O solution the bacterial dry weight could yield 75.3% with the amount of 0.5115 grams. It could be able to withstand acidic conditions and harvest gold from the gold extraction solution after centrifugation and filtration. So this developed biological method could be developed to apply in the industrial production of gold and jewelry industry.

The diversity of soil microorganisms in mulberry root rot disease infesting fields was investigated from The Queen Sirikit Sericulture Center at Kanchanaburi Khon Kaen Sisaket and Ubon Ratchathani provinces. Isolation of the soil microorganisms was performed on four media as nutrient agar (NA) potato dextrose agar (PDA) rose bengal agar (RBG) and modified selective fusarium agar (SFA). Twenty-four bacterial isolates were arisen from NA including gram positive endospore forming rod gram negative rod gram positive cocci and Actinomycetes. Similarly 75 isolates of fungi were gained from PDA RBG and SFA and could be defined to be Aspergillus sp. Chaetomium sp. Curvularia sp. Fusarium sp. Penicillium sp. Phytophthora sp. and Rhizopus sp. by their morphological characteristics. Verification of the causal pathogen of mulberry root rot disease could be accomplished using specific primers for F. solani in which a DNA band at approximately 300 bp was revealed.

At present most human-related products contain a mixture of chemicals for inhibiting microorganisms polluting the environments and harming the users. The purpose of this research was to develop a product using banana and papaya peel extracts as replacers for the chemicals inhibiting microorganisms in heel cream. By extracting raw bananas and papaya peels with coconut oil the studying the efficacy of inhibition on E. coli S. aureus Aspergillus sp. and S. cerevisiae with Disk Diffusion method at the protein concentration were performed as follows: 25 50 100 and 150 micrograms per milliliter. The observation of clear zone to observer clear zone of inhibition. and the Turbidity method using light absorption at a length of 600 nm was also were shown the corresponding results of microbial inhibition. observed and showed the consistent results. Especially the papaya extract having the protein concentration at least of 150 micrograms per milliliter could inhibit all 4 microbe species but could not inhibit S. cerevisiae that indicated a good trend of no harm on human. When mixing the extract in the heel cream it was found that Heel cream containing banana extract papaya and both mixtures displayed the density of 0.9674 0.9103 and 0.8057 gram per cubic meter respectively. They could be stored at room temperature for more than 45 days and still maintained the properties of microbial inhibition by up to 80 percentages. When studying the satisfaction of consumers collected randomly from teenagers to elders at both sexes of 40 people more than 80 percentages of the customers were satisfied with the heel cream from all extracts. These all creams could make the feet soft and moisturized within 1 week. More suggestions were to improve the smell of heel cream products to be suitable for all age of consumers. Therefore this research could be concluded that banana and papaya peel extracts inhibiting microorganisms could be used as a heel cream for further continuously developing at the industrial level.