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The purpose of this research was to create bio-based non-isocyanate polyurethane (Bio-NIPU) resins derived from the tannin of Acacia mangium Willd. bark for the impregnation of ramie fibres (Boehmeria nivea L.) and to investigate the properties of impregnated fibres. Tannin was extracted from the bark of A. mangium using hot water. Tannin-bio-NIPU resin was created using dimethyl carbonate and hexamine. Based on the findings, it is possible to conclude that tannin extract from the bark of Acacia mangium can be used effectively as a renewable alternative to toxic polyols in the development of tannin-Bio-NIPU resins. FTIR spectroscopy was used to confirm the urethane bond formed on the tannin-Bio-NIPU resins. Thermal and mechanical analysis were used to investigate the properties of tannin-Bio-NIPU resins and ramie fibres before and after impregnation. This study shows that the impregnation time of ramie fiber using tannin-Bio-NIPU resins is 30 minutes. The reaction between tannin-Bio-NIPU resins with ramie fiber forms the C=O urethane group as confirmed by FTIR Spectroscopy. The characterization results show that tannin-Bio-NIPU resins has ability to modify ramie fiber via impregnation in order to increase its mechanical properties, thus enhancing its potential for wider industrial application as a functional material.

Tomatoes are a widely consumed fruit due to their rich nutritional profile and can command high market prices, exemplified by varieties like Umagna. Nevertheless, tomatoes are prone to damage. A viable solution involves applying an edible coating derived from Spirulina platensis. This study aims to investigate the effect of Spirulina platensis at different concentration on longevity of Umagna tomatoes during storage depending on the component of edible coating. Employing experimental techniques with descriptive analysis, the research underwent processing via regression and ANOVA tests. Findings demonstrated a connection between Spirulina platensis concentration and parameters such as respiration rate, weight loss, color changes, and shelf life. However, ANOVA results indicated no significant impact on factors like hardness, TAT content, water content, vitamin C content, or total sugar content (F < Fcrit). Notably, tomatoes coated with 0.5% Spirulina platensis displayed the most favorable outcomes, preserving attributes such as reduced respiration and weight loss, while maintaining hardness, TAT content, water content, vitamin C content, and total sugar content. A concentration of 0.5% Spirulina platensis extended the tomatoes’ shelf life to 52 days.

The added value of Lactobacillus acidophilus encapsulation due to its production process is one of the first things that need to be known in calculating techno-economic analysis to determine the sustainability of its downstream. The result of value-added analysis plays an important role in determining which formulation, encapsulate material, and production process should be used. The inoculum media used were skimmed milk and whole milk, the coating material used in this study was Eucheuma cottonii, while the process variations used were spray-drying and freeze-drying methods. There were four treatments in the research that analyzed their added value. Determination of the best treatment was carried out through the scoring method on the value of cell viability, cell morphology, encapsulation effectiveness, process costs, cost of supporting materials, and added value of the product. Added value analysis was carried out using the Hayami and Kawagoe methods. Based on the research results, it can be concluded that added value is most influenced by process costs. The treatments selected were E. cottonii coating material, fresh milk inoculation medium, and spray-drying encapsulation method with an overall score of 22.

Molasses can serve as a natural adhesive for plywood and particleboard. However, several disadvantages remain, including lower dimensional stability and low bonding strength compared to other adhesives. Therefore, modifications are needed to use molasses as an adhesive for plywood. This research aims to improve bio-based molasses (MO) adhesive for plywood using citric acid (CA) adhesive. In addition, this research aims to analyze the effect of adding citric acid and to investigate the optimum hot-pressing temperature to produce the best quality plywood. In the first stage, the molasses and citric acid were combined in a ratio of 100:0, 75:25, 50:50, 25:75, 0:100 w/w%. Then, the second stage focuses on analyzing the influences of pressing temperature based on an optimum first stage. The research demonstrated that the addition of CA altered the gelation time, solid content, viscosity, and pH of the molasses adhesives. In addition, the thermal properties of molasses adhesives were changed after mixing with citric acid. These phenomena indicate changes in characteristics, such as the curing of adhesive. Overall, the characteristics of plywood showed a steady improvement as the CA ratio increased but revealed a significant decline for the 25:75 MO-CA ratio. By raising the pressing temperature from 180°C to 200°C, the quality of plywood was effectively improved. The plywood that was bonded using adhesives with a 50:50 MO-CA ratio exhibited superior mechanical properties and improved dimensional stability compared to the plywood bonded solely with MO. Furthermore, the optimal mechanical and physical properties resulted in plywood bonded with a 50:50 MO-CA ratio when subjected to a pressing temperature of 200°C. The Thermal and FTIR measurements revealed that CA established ester bonds with both the MO and wood veneers. In conclusion, the mechanical characteristics of plywood were improved, while maintaining its excellent dimensional stability. [ABSTRACT FROM AUTHOR]

More than a century after its initial synthesis, urea-formaldehyde (UF) resins still have dominant applications as adhesives, paints, and coatings. However, formaldehyde in this industry produces formaldehyde emissions that are dangerous to health. Scientists have spent the last decade replacing formaldehyde and phenol with environmentally friendly substances such as glyoxal and tannin to create bio-based adhesives. This review covers recent advances in synthesizing glyoxal tannin-based resins, especially those made from sustainable raw material substitutes and changes made to synthetic processes to improve mechanical properties. The efficacy of using tannin-glyoxal adhesives in producing wood-based composites has been proven. The glyoxylate reaction forms cross-linked bridges between the aromatic sites of the tannin and glyoxal molecular structures. Glyoxal tannin adhesive with a greater percentage of glyoxal than tannin will produce an adhesive with better characteristics. The gel time reduces as the hardener concentration rises from 7.5% to 15% when glyoxal is used in adhesives. However, excessive amounts of glyoxal will result in a decrease in viscosity values. Glyoxal exhibits faster delivery degradation when it reaches a maximum temperature of approximately 130°C, although it initiates the curing process slightly slower at 110°C. Adding glyoxal to tannin-based adhesives can improve the mechanical properties of composite boards. The wet shear strength of the resulting plywood is increased by 105.4% with the addition of 5-weight percent tannin-based resin with glyoxal as a cross-linker in Soy Protein Adhesive. With glyoxal as a hardener, the panels produced showed good internal bond strengths (>0.35 MPa) and met the international standard specifications for interior-grade panels. [ABSTRACT FROM AUTHOR]

Seaweed is chemically and phytochemically one of the most diverse marine species that has received special interest as a feed ingredient, supplement, and additive for poultry. The abundant biomass production in the tropics and their bio-active compounds profile such as alginate, fucoidan, fucoxanthin, phlorotannin, laminarin, and long-chain polyunsaturated fatty acids (LC-PUFAs) possess many biological roles as antioxidant, antimicrobials, and immunomodulatory effects that are beneficial to improve gut health and performance of poultry. However, seaweeds use as a poultry feed ingredient is limited by their high content of salt (NaCl), anti-nutritional factors, indigestible nutrients, and low energy content. High NaCl content in poultry rations can lead to diarrhoea and high mortality. On the other hand, seaweed carbohydrates can inhibit nutrient absorption in the poultry digestive tract. In this review, we discuss the recent updates on the use of seaweed in poultry feeding, the impacts of various processing methods to eliminate antinutritional factors, and future directions of processing technology that need to be developed to optimise the use of seaweeds in poultry. This includes biological, chemical, and physical approaches to reduce seaweed NaCl, optimise bioactive compounds extraction and purification, reduce anti-nutrition content, and decompose seaweed indigestible carbohydrates before being mixed as a poultry feed ingredient. In the production and health aspects of poultry, bioactive constituents extracted from seaweed possess antimicrobial and immunomodulatory effects that have positive associations with the improvement of production performance. [ABSTRACT FROM AUTHOR]

Roselle plant (Hibiscus sabdariffa L.) has many benefits. Vitamin C is an antioxidant in which the human body required. It contains a high amount of vitamin C. However, vitamin C is susceptible to high temperatures. Proper extraction treatment conditions produce optimum vitamin C. This study aims to determine the optimization of vitamin C in rosella flowers. This research uses UAE with Qsonica type - Q500 (500 W, 20 kHz). Extraction treatment conditions control amplitude, time and amount of solvent. The research method used is a laboratory experiment with the RSM (Response Surface Methodology) type CCD (Central Composite Design) approach. The research method was an experimental laboratory using a CCD (Central Composite Design) via RSM (Response Surface Methodology) with an amplitude level from 20% to 50%, a time level from 10 minutes to 20 minutes, and a ratio of the amount of solvent from 140 mL to 260 mL by weight. The results showed that the length of time and the amount of solvent had a significant effect, while the amplitude had no significant effect. The significant quadratic model at p value 0.05 and R2 0.9221 with optimum UAE conditions in the treatment combination of 50 percent amplitude, 20 minutes of time, and 140 ml of solvent resulted in an optimum vitamin C content of 38.76 mg/100g. This research can be used as a reference to determine the value of vitamin C with different amplitude, time, and amount of solvent from the research data. [ABSTRACT FROM AUTHOR]

The massive potential of pineapple fruit production can produce a sizable amount of waste, around 75% (w/w) of pineapple weight, contributing to global environmental problems. For this reason, biorefinery techniques are urgently needed to convert pineapple plantation waste into high-value-added bioproducts including bromelain, various sugars, xylooligoscharide, xylitol, and ethanol. The purpose of this study was to examine the effectiveness of converting pineapple plantation waste into bromelain, xylitol, and ethanol. In this study, the activity of the bromelain enzyme was tested in each part of the pineapple plant waste. The configuration of the hydrolysis and fermentation processes used to make ethanol and xylitol from the rest of the pineapple plant waste from bromelain extraction was also investigated. Bromelain is a proteolytic enzyme found in pineapple plants and can be isolated from every part of pineapple plant waste. Enzyme activity under several conditions, such as crude extract, pure extract, and dried extract, has been studied to determine the best conditions for the downstream process of this enzyme's production in the future. The purification of bromelain involved the utilization of the precipitation method followed by dialysis, whereas the drying process of bromelain employed the freeze-drying method. The bromelain enzyme specific activity is shown to be highest in the pineapple stem, as observed in crude-extract (1.45 ± 0.06 CDU/mg), purified-extract (10.38 ± 0.06 CDU/mg), and dried-extract (12.05 ± 0.43 CDU/mg) conditions. Using the pineapple stem to extract bromelain can produce lignocellulosic waste, which is made up of 39.47% starch, 19.96% hemicellulose, 36.44% cellulose, and 6.05% lignin. The high content of starch, cellulose, and hemicellulose has the potential to be used as feedstock for ethanol and xylitol fermentation. In this study, ethanol and xylitol fermentation were carried out using two methods: separate hydrolysis and fermentation methods (SHF) and semi-simultaneous saccharification and fermentation methods (semi-SSF). As a result, fermentation using the semi-SSF method produced ethanol with a higher titer and yield (22.12 ± 0.05 g/L and 0.44 ± 0.00 g/g, respectively). However, the production of xylitol was found to be insignificant, regardless of whether it was obtained using SHF or semi-SSF. The purification of bromelain involved the utilization of the precipitation method followed by dialysis, whereas the drying process of bromelain employed the freeze-drying method. [ABSTRACT FROM AUTHOR]

Phenol-formaldehyde (PF) resin is one of the most well-known adhesives for exterior use. PF adhesive is one of the commercial thermoset polymers that is used extensively due to its many benefits. This study investigated the influence of different types and levels of catalysts, i.e., NaOH and CaCO3 at 1% and 5% based on the solids content of PF resin on the adhesive properties, adhesion, and cohesion strength of PF resin. The results show that the catalyst type significantly influenced the PF adhesive viscosity and pH. Furthermore, the catalyst level significantly affected the PF adhesive's solids content, viscosity, and gelation time. The cohesion strength of PF-CaCO3-1% was more significant than the PF control at 75 °C. According to the DMA analysis, the mixed PF-NaOH-5% provided the highest storage modulus, followed by the PF-CaCO3-1%, with values that were not statistically different from one another. The adhesion strength of PF-CaCO3-1% was the highest, whereas the adhesion strength of the PF control was the lowest, as confirmed by the cohesion strength. According to the findings, adding CaCO3-1% as a catalyst of PF resin would result in better adhesive adhesion and cohesion properties for wood composites in the future. [ABSTRACT FROM AUTHOR]