Nutritional profiling and in silico analysis of pharmacological activities from local rice Pulu Mandoti fermented with Pleurotus spp.

Pulu Mandoti, a local red rice (Oryza sativa L.) variety popular among Sulawesi residents, has gained recognition for its perceived health benefits, especially as a preferred dietary option for individuals with diabetes or those seeking to prevent obesity. Given the increasing consumption of mushrooms, particularly Pleurotus species, renowned for their nutritional and medicinal attributes, this study delves into the transformative effects of Pleurotus spp. fermentation on Pulu Mandoti, the indigenous rice variety. Proximate analysis disclosed elevated dry matter (91.99 ± 0.61%), crude protein (8.55 ± 0.15%), and crude fat (1.34 ± 0.05%) in Pleurotus cystidiosus fermentation compared to Pleurotus ostreatus and Pleurotus djamor. Concurrently, antioxidant and antidiabetic activities were notably improved in all Pleurotus fermentations. Pulu Mandoti fermented with P. cystidiosus outperformed other treatments, aligning with molecular docking results pinpointing 11-Eicosenoic acid, methyl ester, and butylated hydroxytoluene as optimal interactors with antioxidant receptors 5O0x and 2CKJ. Butylated hydroxytoluene demonstrated interactions with the antidiabetic receptor 2QV4, along with 9-Octadecenoic acid, methyl ester. These compounds, previously unreported in Pleurotus, displayed promising attributes as antioxidants and antidiabetic agents. Furthermore, the investigation delved into the fatty acid profiles, emphasizing the diverse range of potential bioactive compounds in fermented Pulu Mandoti. The findings of this research present a potential functional food rich in natural antioxidants and antidiabetic compounds, highlighting the yet undiscovered capabilities of Pleurotus spp. fermentation in augmenting the nutritional composition and bioactivity of indigenous rice varieties, specifically Pulu Mandoti.

Production of codon-optimized Factor C fragment from Tachypleus gigas in the Pichia pastoris GS115 expression system for endotoxin detection.

BACKGROUND: Factor C (FC) is widely used as a standard material for endotoxin testing. It functions as a zymogenic serine protease and serve as a biosensor that detects lipopolysaccharides. Prior investigations involving molecular docking and molecular dynamics simulations of FC demonstrated an interaction between the C-type lectin domain (CLECT) and the ligand lipopolysaccharide (lipid A). In this study, our aim was to assess the stability of the interaction between fragment FC and the lipid A ligand using protein modeling approaches, molecular docking, molecular dynamics simulation, and gene construction into the pPIC9K expression vector. METHODS AND RESULTS: The FC structure was modelled by online tools. In this case, both molecular docking and MD simulations were applied to identify the interaction between protein and ligand (lipid A) including its complex stability. The FC structure model using three modeling websites has varied values, according to a Ramachandran plot study. When compared to other models, AlphaFold server modeling produced the best Ramachandran findings, with residues in the most advantageous area at 88.3%, followed by ERRAT values at 89.83% and 3D Verify at 71.93%. From the docking simulation of FC fragments with three ligands including diphosphoryl lipid A, FC-Core lipid A, and Kdo2 lipid A can be an activator of FC protein by binding to receptor regions to form ligand-receptor complexes. MD simulations were performed on all three complexes to assess their stability in water solvents showing that all complexes were stable during the simulation. The optimization of recombinant protein expression in Pichia pastoris was conducted by assessing the OD value and protease activity. Induction was carried out using 1% (v/v) methanol in BMMY media at 30°C for 72 h. CONCLUSIONS: Protein fragments of Factor C has been proven to detect endotoxins and serve as a potential biomarker. Molecular docking simulation and MD simulation were employed to study the complex formation of protein fragments FC with ligands. The expression of FC fragments was successfully achieved through heterologous expression. We propose optimizing the expression of FC fragments by inducing them with 1% methanol at 30°C and incubating them for 72 h. These optimized conditions are well-suited for upscaling the production of recombinant FC fragments using a bioreactor.

Characterization, protein modeling, and molecular docking of factor C from Indonesian horseshoe crab (Tachypleus gigas).

BACKGROUND: Horseshoe crab (Tachypleus gigas) amebocytes are useful biomedical components for endotoxin detection, and their growing needs for biomedical purposes cause the horseshoe crab population to decline. Factor C synthesis via genetic engineering offers a solution to replace natural horseshoe crab's factor C and prevent its excessive harvest from nature. In response to these concerns, this study aimed to characterize the amebocyte lysates and factor C protein modeling of T. gigas originated from Banyuasin South Sumatra Estuary. METHODS AND RESULTS: Sampling of T. gigas was carried out in Banyuasin South Sumatra Estuary, Indonesia. The endotoxin test or TAL (Tachypleus amebocyte lysates) assay was performed using gel coagulation method. Protein characterization of protease enzyme was conducted by protease activity, SDS-PAGE, and zymogram analysis. The cDNA of mitochondrial COI gene was amplified for molecular identification followed by cDNA cloning of factor C. Protein modeling was investigated by molecular docking and molecular dynamic (MD) simulation. Endotoxin test results showed that TAL-35 had endotoxin sensitivity in a range of 0.0156-1 EU/ml, while TAL 36 had a sensitivity between 00,625 and 1 EU/ml. T. gigas amebocytes have protease activity in molecular mass sizes less than 60 kDa, with 367 U/ml for TAL 35 and 430 U/ml for TAL 36. The molecular identification revealed 98.68% identity similarity to T. gigas. The docking results suggested three ligands; i.e., diphosphoryl lipid A, core lipid A, and Kdo2 lipid A can be activators of the factor C protein by binding to the region of the receptor to form a ligand-receptor complex. CONCLUSIONS: Endotoxins can be detected using horseshoe crab amebocytes. The presence of proteases is considered responsible for this ability, as evidenced by casein zymogram results. According to docking and MD analysis, we found that lipopolysaccharides (LPS) participate to the binding site of factor C.