Technical and economic performance of the dithionite-assisted organosolv fractionation of lignocellulosic biomass

The development of biomass pretreatment approaches that, next to (hemi)cellulose valorization, aim at the conversion of lignin to chemicals is essential for the long-term success of a biorefinery. Herein, we discuss a dithionite-assisted organosolv fractionation (DAOF) of lignocellulose in n-butanol and water to produce cellulosic pulp and mono-/oligo-aromatics. The present study frames the technicalities of this biorefinery process and relates them to the features of the obtained product streams. Via the extensive characterization of the solid pulp (by acid hydrolysis-HPLC, ATR-FTIR, XRD, SEM and enzymatic hydrolysis-HPLC), of lignin derivatives (by GPC, GC-MS/FID, 1H-13C HSQC NMR, and ICP-AES) and of carbohydrate derivatives (by HPLC) we comprehensively identify and quantify the different products of interest. These results were used for inspecting the economic feasibility of DAOF. The adoption of a dithionite loading of 16.7% w/wbiomass and of an equivolumetric mixture of n-butanol and water, which led to a high yield of monophenolics (~20%, based on acid insoluble lignin, for the treatment of birch sawdust), was identified as the most profitable process configuration. Furthermore, the treatment of various lignocellulosic feedstocks was explored, which showed that DAOF is particularly effective for processing hardwood and herbaceous biomass. Overall, this study provides a comprehensive view of the development of an effective dithionite-assisted organosolv fractionation method for the sustainable upgrading of lignocellulosic biomass.

Fractionation of Regenerated Silk Fibroin and Characterization of the Fractions

The molecular weight (MW) of regenerated silk fibroin (RSF) decreases during degumming and dissolving processes. Although MW and the MW distribution generally affect polymer material processability and properties, few reports have described studies examining the influences of MW and the distribution on silk fibroin (SF) material. To prepare different MW SF fractions, the appropriate conditions for fractionation of RSF by ammonium sulfate (AS) precipitation process were investigated. The MW and the distribution of each fraction were found using gel permeation chromatography (GPC) and SDS-polyacrylamide electrophoresis (SDS-PAGE). After films of the fractionated SFs formed, the secondary structure, surface properties, and cell proliferation of films were evaluated. Nanofiber nonwoven mats and 3D porous sponges were fabricated using the fractionated SF aqueous solution. Then, their structures and mechanical properties were analyzed. The results showed AS precipitation using a dialysis membrane at low temperature to be a suitable fractionation method for RSF. Moreover, MW affects the nanofiber and sponge morphology and mechanical properties, although no influence of MW was observed on the secondary structure or crystallinity of the fabricated materials.

Anti-salmonellosis agent for foodborne illness from Mangifera odorata (kuini) extracts

Salmonellosis infection caused by Salmonella bacteria is a public endemic problem in Malaysia with long-term morbidity and mortality effects. Thus, this study aimed to explore the antipathogenic activity of natural extracts from Mangifera odorata against two Salmonella species causing Salmonellosis. The extracts were derived from peel, flesh, and kernel seed of M. odorata. The inhibition performance of the extracts against both Salmonella enterica serovar Typhimurium and Salmonella enterica serovar Enteritidis bacteria were subsequently tested by using a bioassay-guided fractionation method. Results showed that the extracts derived from the kernel seed had the highest inhibition percentage of 83-90% against the Salmonellosis infection, followed by the peel with an inhibition of 61-67%, and lastly the flesh with an inhibition of 53-69%. The inhibition activities of hexane extracted flesh (FCH), methanol extracted peel (PCM), and methanol treated kernel seed (KTM) against S. enterica ser. Typhimurium bacteria were 59, 67 and 83%, respectively. Furthermore, the S. enterica ser. Enteritidis bacteria were found to be highly susceptible against the methanol extracted kernel seed (KCM), followed by the hexane extracted peel (PCH) and flesh (FTH) with the inhibition percentage of 90, 69 and 59%, respectively. The highly active anti-Salmonellosis performance of M. odorata extracts was attributed to its intrinsically high total phenolics content at 8-10 g GAE/g extract, high ferric reducing antioxidant power value (FRAP) at 18-22 g Fe2+/g extract and excellent scavenging activity with the inhibition performance ranges between 86% and 90%. This study revealed the antipathogenic activity of methanol extracts of M. odorata kernel seed inhibited the growth of both S. enterica ser. Typhimurium and S. enterica ser. Enteritidis bacteria. This study also discovered the prophylactic property of natural compounds in M. odorata kernel seed extracts and could be used as an anti-Salmonellosis agent. In the near future, M. odorata can be developed as an innovative functional food source for specific groups that are vulnerable to Salmonellosis

A review of application of natural products as fungicides for chili

Anthracnose disease in chillies is a serious problem for farmers. So far, synthetic fungicides have been used as solution for the treatment of this disease. However, the side effects of synthetic fungicides to public health and environment raised awareness on alternative fungicides derived from natural resources. This paper aims to review plants that are potential as an alternative to fungicides for chili plantation, fabrication of test solutions, in vitro and in vivo fungicide test. Many plants were investigated as alternatives to plant-based fungicide. The utilization of leaves as samples including rhizomes, roots, tubers, weevils, seeds, fruit, flowers and other parts of the plant. The extract fabrication method used as a fungicide test include: maceration method, gradual fractionation method, and decoction method. The maceration method is the method most widely used to extract fungicidal active compounds from plants. Some studies that carried out in vitro tests were unable to compare with synthetic fungicides so it was not possible to determine their effectiveness for plant-based fungicide for chillies when compared to synthetic fungicides. In vitro Extract of 80% alcohol and 10%/60% n-hexane of pacar cina (Aglaia odorata L.) leaves can be compared with the performance of propineb 0.2%. In addition, the 60% and 70% kirinyuh (Chromolaena odorata L.) leaf extracts were also able to match Acrobat 0.2% performance in vitro. Based on the in vivo test, suren (Toona sureni Merr) leaf extract and nut bulbs can be used as an alternative to vegetable / natural fungicides to help overcome the problem of anthracnose in chilies.

Comprehensive Analysis of Proteasomal Complexes in Mouse Brain Regions Detects ENO2 as a Potential Partner of the proteasome in the Striatum

Defects in the activity of the proteasome or its regulators are linked to several pathologies including neurodegenerative diseases. We hypothesize that proteasome heterogeneity and its selective partners vary across brain regions and have a large impact on proteasomal catalytic activities. Using neuronal cell cultures and brain tissues obtained from mice, we compared proteasomal activities from two distinct brain regions affected in neurodegenerative diseases, the striatum and the hippocampus. The results indicated that proteasome activities and their responses to proteasome inhibitors are determined by their subcellular localizations and their brain regions. Using a iodixanol gradient fractionation method, proteasome complexes were isolated, followed by proteomic analysis for proteasomal interaction partners. Proteomic results revealed gamma enolase (ENO2), a known proteasome partner, has more affinity to proteasome complexes purified from the striatum than to those from the hippocampus. These results highlight a potential key role for non-proteasomal partners of proteasome regarding the diverse activities of the proteasome complex recorded in several brain regions.

Isolasi dan Karakterisasi Enzim Bromelain dari Bonggol dan Daging Buah Nanas (Ananas comosus)

Penelitian ini bertujuan untuk mengisolasi dan memurnikan bromelain yang diekstrak dari bagian tanaman nanas (Ananas comosus) melalui metode fraksinasi menggunakan garam ammonium sulfat, diikuti dengan proses dialisis. Aktivitas spesifik tertinggi terdapat pada fraksi ammonium sulfat 50-80% (fraksi 3) baik untuk sampel bagian bonggol maupun bagian daging buah nanas, masing-masing adalah sebesar 0,30 U/mg dan 0,21 U/mg. Fraksi 3 dari bagian bonggol memiliki tingkat kemurnian 132,65 kali enzim kasarnya sedangkan fraksi 3 dari bagian daging buah nanas memiliki tingkat kemurnian 108,47 kali dari enzim kasarnya. Proses dialisis memberikan nilai aktivitas spesifik dan tingkat kemurnian enzim tertinggi pada fraksi 3 dari bagian bonggol nanas yaitu sebesar 0,33 U/mg dengan kenaikan tingkat kemurnian menjadi sebesar 141,58 kali enzim kasarnya. Uji kestabilan termal terhadap fraksi enzim hasil dialisis menunjukkan bromelain dari bonggol memiliki kestabilan termal yang lebih tinggi dibandingkan dengan bromelain dari daging buah nanas. pH dan suhu optimum dari enzim bromelain adalah 7,0 dan 37oC. Kata kunci: Ananas comosus, bonggol nanas, bromelain, aktivitas spesifik, pemurnian ABSTRACT The aim of this study was to isolate and purify the bromelain extracted from part of pineapple fruit (Ananas comosus) through fractionation method using ammonium sulfate followed by dialysis. The highest specific activity on ammonium sulfate fraction was 50-80% (fraction 3) both for the sample of the core and the flesh of pineapple, each was 0.30 U/mg and 0.21 U/mg. The fraction 3 of the core had a purity level 132.65 times of the crude enzyme while fraction 3 of the pineapple flesh had a purity level 108.47 times of the crude enzyme. From the dialysis process found the highest value of specific activity on fraction 3 of the pineapple core of 0.33 U/mg with a purity level of and 141.58 times of the crude enzyme. Fraction of the core has higher thermal stability than the fraction of the flesh. The optimum temperature and pH of this enzyme was 37oC and 7.0. Keywords: Ananas comosus, pineapple core, bromelain, specific activity, purification