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The increased processing of coffee beans has generated huge amount of coffee husk, which are improperly disposed. Inappropriate disposal of coffee husk has led to release of toxic compounds to the environment causing serious environmental concerns. To mitigate the impact of improperly disposed coffee husk, it is suggested for valorisation of the coffee husk. Hence, this study has focussed on identifying the potential of coffee husk in maximizing the sugar yield from it which can be converted to value added product. Deep eutectic solvent (DES) involving choline chloride and lactic acid (ChCl:LA) mixed at 1:4 molar ratio was studied to investigate the effect of DES pretreatment on coffee husk to produce reducing sugar in the hydrolysis process. Pretreatment conditions of the biomass were optimized for biomass loading (5-20%, w/w), temperature (70-120 °C), and duration (60-240 min) using Response Surface Methodology (RSM) for obtaining maximum yield of reducing sugar. The RSM model predicted an optimal pretreatment condition of biomass loading with 20% (w/w), pretreated at 120 °C for 231.80 min to achieve maximum sugar yield (30.522%). The pretreatment effect on biomass composition was analyzed using the Van Soest method, which showed an increase in the cellulose content along with the hemicellulose removal when compared with the native biomass. Moreover, evaluation of chemical structural changes also confirmed the effectiveness of DES pretreatment. Thus, the current study would illustrate the potential of coffee husk to produce value-added compounds from it.

Biogas production is one of the means to manage the cassava pulp waste obtained from the cassava processing plants. The success of the process is determined by the hydrolysis in an anaerobic digester. When the digester failure is found, the new microbial consortium inoculum is introduced to the system with the long period of set up time. This research aimed to construct the endemic microbial consortium by re-cultivating the cellulolytic microbial consortia obtained from cassava pulp and digester wastewater with the expected shorter set up time. Modifications of enrichment and re-cultivation methods by varying the nutrients, pH and temperature improved the enzymatic hydrolysis yields, as reducing sugars, of CMC, rice straw and cassava pulp substrates approximately 9, 3, and 13 times, respectively. To analyze the enzymatic activities of the selected microbial consortia, the cellulase enzyme was extracted, partially purified and analyzed on CMC-zymogram. The ~130 kDa-sized cellulase enzyme was identified with endocellulase activity, and it was considered as a relatively large molecular size molecule compared to most bacterial endocellulases. The selected microbial consortia were tested for their biomass degradation capacities, and the optimal operational condition was obtained at pH 7.0 and 30 °C. This optimal condition showed the proof of the concept that this re-cultivated consortium could be applied in on-site digester with high efficiency.

The traditional Thai herbal compress is composed of six different types of herbs including Ginger (Zingiber cassumunar), Turmeric (Curcuma longa Linn.), Soap Pod (Acacia concinna), Kaffir lime (Citrus hystrix), Lemongrass (Cymbopogon citratus), and Tamarind (Tamarindus indica Linn.). Herbal compress is used in treatment of Thai traditional massage to relieve the body pain and muscle strains. The objective of this work is to perform chemical profiling and extraction modelling of herbal compress obtained from solvent extraction method. The kinetic models, The second order and Fick‘s second law, representing the extraction behaviors of bioactive compounds were constructed to fit with experimental data of solvent extraction. Under tested condition, the extraction equilibrium was reached after 360 min and the second-order model gives the best fit for the experimental data with high coefficients of correlation (R2 = 0.9927). Additionally, chemical profiling analysis showed that the amounts and variations of bioactive components in drying-pretreated herbal compress were more abundant than that of untreated sample. This finding could be applied further for preparation and production of traditional Thai herbal compress in the industrial scale.

Herbal compress ball is currently one of important products of Thailand for exporting sales worldwide. It is used in Thai traditional medical treatment and spa to reduce muscle pain and relaxation. This research aimed to generate the mathematical models representing the behaviors of herbs in hot air drying to extend shelf life for exporting sales. Here, six types of herbs, including Prai (Zingiber cassumunar Roxb.), Turmeric (Curcuma longa Linn.), Lemongrass (Cymbopogon citratus), Kaffir lime (Citrus hystrix), Soap Pod leaves (Acacia concinna) and Tamarind Leaves (Tamarindus indica Linn.) were dried in different temperature at 60, 70, and 80 °C. Fours drying models, Page, Henderson and Pabis, and Logarithmic and Fick's second law equation were applied with experimental data of drying herbs to predict the rate of diffusion of water. The results showed that the Page model is the most suitable model due to the highest decision coefficient (R2) but the lowest Root Mean Square Error (RMSE). The effective moisture diffusivity (Deff) of the herbs in herbal compress ball was increased with increased the drying temperature. The size of the herb particle translated inversely with effective moisture diffusivity (Deff) value.