Fed-batch treatment attenuates diffusional limitation while preparing high solid microfibrillated cellulose from Gelidium amansii.

This study investigates the effects of fed-batch treatment on the fibrillation degree and properties of Gelidium amansii-derived microfibrillated cellulose (MFC). Fed-batch milling was conducted with the initial solid loading of 1 % w/v followed by three stages of feeding to obtain a final solid concentration of 5 % w/v. This process provides a high-solid MFC of around 10 %, while batch milling only provides the maximum solid loading of 4 %. It also reduces approximately 83 % power consumption of batch milling at the same solid loading (4 %). The obtained MFC 5 % has lower fibrils length (14.9 µm) and width (16.46 nm), but higher consistency index (>250 Pa.s) than MFC 1 % (22 µm, 21 nm, 5.88 Pa.s). The crystallinity and maximum decomposition temperatures of both MFCs are comparable, varying at 49-53 % and 318 °C-320 °C. In summary, fed-batch treatment is promising for the techno-economic development of MFC production by lowering energy and maintaining product quality.

Occupational lead exposure health risk assessment and heme biosynthesis: A study on batik artisans in yogyakarta, Indonesia.

This study aims to assess dermal and inhalation lead exposure levels among batik industry workers and evaluate noncarcinogenic and carcinogenic health risks associated with lead exposure. We investigate potential relationships between lead exposure (dermal average daily dose and inhalation exposure concentration) and the workers' blood hemoglobin levels (Hb), as well as their urinary ALA (u-ALA) concentrations. Additionally, we explore any possible associations between Hb and u-ALA levels among the workers and identify various factors influencing lead exposure levels. A total of 30 workers were recruited for the study. Interviews and exposure sampling were conducted to measure dermal and inhaled lead exposure. Sample analysis methods include XRF for exposure samples, spectrophotometry for u-ALA, and HiCN colorimetric for Hb. Carcinogenic and noncarcinogenic risk assessments, correlation analysis, as well as ANOVA for factors analysis, were performed. The average dermal exposure dose and inhalation exposure concentration of lead were 6.53 ± 3.2 ng/kg/day and 0.021 ± 0.015 µg/m3, respectively. Hazard Index (HI) values for all workers were below 1 (average: 0.372 ± 0.155), indicating no expected noncarcinogenic health effects due to lead exposure. The average Excess Lifetime Cancer Risk (ELCR) was (5.18 ± 3.84) × 10-8, significantly below acceptable limits. Correlation analysis revealed a significant negative correlation between Hb and u-ALA (r = -0.519, p = 0.058 for male workers and r = -0.531, p = 0.034 for female workers), supporting their use as lead exposure biomarkers. The factors analysis demonstrated a significant impact of working conditions on inhalation exposure (p = 0.018), with outdoor workers experiencing lower lead inhalation. This research provides crucial insights into potential dangers faced by batik workers due to lead exposure, emphasizing the importance of targeted interventions. The strong correlation between Hb and u-ALA indicates their combined effectiveness in detecting lead exposure, even at low levels. The study underscores the significance of outdoor work as a protective measure against inhaling heavy metals, such as lead, present in the air. The assessment of health risks associated with lead exposure in the batik industry lays the groundwork for informed decision-making and interventions to protect workers' well-being, particularly in informal sectors workplaces where health risks are often overlooked.

Transformation of financial institutions grants from the government to inclusive financial institutions in Indonesia.

Low-income communities have limited capital and access to money or loans from formal financial institutions. To solve the problems, the government provides solutions, one of them is by forming a microfinance program, namely Rural Agribusiness Business Development (PUAP). PUAP program is one of the grant activities to farmer group association (Gapoktan) with a total capital assistance of IDR 100 million. The problem with the 52,186 Gapoktan units that participated in PUAP activities, only 7,703 units (15%) were transformed into Agribusiness Microfinance Institutions (LKMA). This paper differs from others as it briefly explains the PUAP/MFI's institutional transformation and the factors that affect its sustainability, which is so far still limited discussed. The paper aims to see what transformations Gapoktan becomes an inclusive LKMA and the level of sustainability of the LKMA. The research was conducted in Kendal Regency, Central Java- Indonesia, in 2022 on 5 LKMA. The process of transforming LKMA into an inclusive financial institution is analyzed descriptively. LKMA sustainability levels were analyzed using a multidimensional scaling (MDS) approach with the Rapfish application. So far, MDS with the Rapfish application is still very limited for microfinance analysis. MDS analysis is employed because it is relatively simple and effective for looking at sensitive attributes in improving sustainability and generating leverage attributes that can be used for policy-making. The result study shows that the transformation of PUAP into LKMA is driven by the ability to improve legality, financial governance and diversify the customer's business field. The five LKMAs have a sustainability status of 'sufficient' in running their business, with an index value of more than 50%. The study recommends 1) the Indonesian government could assist LKMA in improving its legality and 2) LKMA's management should get training by experts to improve its financial capability to manage the cost saving.

An Integrated Process for the Xylitol and Ethanol Production from Oil Palm Empty Fruit Bunch (OPEFB) Using Debaryomyces hansenii and Saccharomyces cerevisiae.

Oil palm empty fruit bunch (OPEFB) is the largest biomass waste from the palm oil industry. The OPEFB has a lignocellulose content of 34.77% cellulose, 22.55% hemicellulose, and 10.58% lignin. Therefore, this material's hemicellulose and cellulose content have a high potential for xylitol and ethanol production, respectively. This study investigated the integrated microaerobic xylitol production by Debaryomyces hansenii and anaerobic ethanol semi simultaneous saccharification and fermentation (semi-SSF) by Saccharomyces cerevisiae using the same OPEFB material. A maximum xylitol concentration of 2.86 g/L was obtained with a yield of 0.297 g/gxylose. After 96 h of anaerobic fermentation, the maximum ethanol concentration was 6.48 g/L, corresponding to 71.38% of the theoretical ethanol yield. Significant morphological changes occurred in the OPEFB after hydrolysis and xylitol and ethanol fermentation were shown from SEM analysis.

Extraction of Vanillin Following Bioconversion of Rice Straw and Its Optimization by Response Surface Methodology.

Value-added chemicals, including phenolic compounds, can be generated through lignocellulosic biomass conversion via either biological or chemical pretreatment. Currently vanillin is one of the most valuable of these products that has been shown to be extractable on an industrial scale. This study demonstrates the potential of using rice straw inoculated with Serpula lacrymans, which produced a mixture of high value bio-based compounds including vanillin. Key extraction conditions were identified to be the volume of solvent used and extraction time, which were optimized using response surface methodology (RSM). The vanillin compounds extracted from rice straw solid state fermentation (SSF) was confirmed through LC-ESI MS/MS in selective ion mode. The optimum concentration and yield differed depending on the solvent, which was predicted using 60 mL ethyl acetate for 160 min were 0.408% and 3.957 µg g-1 respectively. In comparison, when ethanol was used, the highest concentration and yields of vanillin were 0.165% and 2.596 µg g-1. These were achieved using 40 mL of solvent, and extraction time increased to 248 min. The results confirm that fungal conversion of rice straw to vanillin could consequently offer a cost-effect alternative to other modes of production.

Pre-treatment of thickened waste activated sludge (TWAS) for enhanced biogas production via the application of a novel radial horn sonication technology.

The efficacy of sonication as a pre-treatment to anaerobic digestion (AD) was assessed using thickened waste activated sludge (TWAS). Efficiency was measured in relation to solubilisation, dewaterability, and AD performance. Eighteen experimental conditions were evaluated at low frequency (20 kHz), duration (2-10 s), amplitude (∼8-12 µm) and applied pressure (0.5-3.0 barg), using a sonix™ patented titanium sonoprobe capable of delivering an instantaneous power of ∼6 kW provided by Doosan Enpure Ltd (DEL). An optimised experimental protocol was used as a pre-treatment for biochemical methane potential (BMP) testing and semi-continuous trials. Four digesters, with a 2-L working volume were operated mesophilically (37 ± 0.5 °C) over 22 days. The results showed that the sonix™ technology delivers effective sonication at very short retention times compared to conventional system. Results demonstrate that the technology effectively disrupts the floc structures and filaments within the TWAS, causing an increase in solubilisation and fine readily digestible material. Both BMP tests and semi-continuous trials demonstrated that sonicated TWAS gave higher biodegradability and methane potential compared to untreated TWAS. Partial-stream sonication (30:70 sonicated to untreated TWAS) resulted in a proportionate increase in biogas production illustrating the benefits of full-stream sonication.

Comparison of mesophilic and thermophilic anaerobic digestion of sugar beet pulp: performance, dewaterability and foam control.

Digestion of sugar beet pulp was assessed in relation to biogas and methane production, foaming potential, and digestate dewaterability. Four 4-litre working volume digesters were operated mesophilically (37±0.5 °C) and four thermophilically (55±0.5 °C) over three hydraulic retention times. Digesters were operated in duplicate at organic loading rates (OLR) of 4 and 5 g volatile solids l(-1) day(-1) without water addition. Thermophilic digestion gave higher biogas and methane productivity than mesophilic and was able to operate at the higher OLR, where mesophilic digestion showed signs of instability. Digestate dewaterability was assessed using capillary suction time and frozen image centrifugation. The occurrence of, or potential for, stable foam formation was assessed using a foaming potential test. Thermophilic operation allowed higher loadings to be applied without loss of performance, and gave a digestate with superior dewatering characteristics and very little foaming potential.