Lanostane triterpenoids from mycelia-associated Ganoderma sinense and their anti-inflammatory activity.

Seven previously undescribed lanostane triterpenoids, ganoderic acid M1 (1), M2 (2), M3 (3), M4 (4), M5 (5), M6 (6), and M7 (7), together with eight known compounds, were isolated from mycelia of the basidiomycete Ganoderma sinense (Ganodermataceae). The structures of all compounds were elucidated by spectroscopic analysis. The possible biosynthetic pathway of these fifteen triterpenoids was proposed. Some of the compounds were evaluated for their anti-inflammatory activity by measuring the production of nitric oxide (NO), TNF-α, and IL-6 in RAW264.7 macrophage cells induced by lipopolysaccharide. Lanosta-7,9(11),24-trien-3ß,15α,22ß-triacetoxy-26-oic acid (14) exhibited the strongest inhibition of NO production with an IC50 of 0.6 ± 0.1 µM and completely inhibited the secretion of TNF-α and IL-6 at 10 µM. The structure-activity relationship of the anti-inflammatory activity is discussed.

Novel production of biodispersant by Serratia marcescens UCP 1549 in solid-state fermentation and application for oil spill bioremediation.

Oil spills in aquatic ecosystems cause irreparable damage to marine life and the coastal populations of affected areas. In recent years, chemical dispersants have been extensively used to remedy these impacted ecosystems, although these agents have been increasingly restricted due to their toxic potential. In this context, biosurfactants are emerging as a promising alternative to chemical dispersants, which have some advantages including low toxicity, high biodegradability and good ecological acceptability. Thus, this study aimed to the production of biosurfactant by the bacteria Serratia marcescens UCP 1549 for application as biodispersant. The experiment was carried out using wheat bran as substrate in solid-state fermentation (SSF) as low-cost technology. Biosurfactant production was verified by the reduction of surface tension (28.4 mN/m) and interfacial tension (4.1 mN/m) with n-hexadecane. Also, promising result of emulsification (94%) with burned motor oil was obtained. Acid precipitation yielded 52.0 g/kg dry substrate of biosurfactant, that was identified as an anionic compound of a lipopeptide nature by the Zeta potential and FTIR spectrum, respectively. The biomolecule showed stability under extreme conditions of temperature, pH and salinity, as well as low toxicity against the microcrustacean Artemia salina. In addition, the biosurfactant demonstrated excellent properties to dispersing burned motor oil in water (ODA = 50.24 cm2) and to washing of marine stones (100% removal of burned motor oil). Therefore, these results confirm SSF as a sustainable technology for the production of biodispersant by S. marcescens UCP 1549, promising in the bioremediation of marine ecosystems impacted by petroderivatives.

Bacterial nanocellulose: engineering, production, and applications.

Bacterial nanocellulose (BNC) has been emerging as a biomaterial of considerable significance in a number of industrial sectors because of its remarkable physico-chemical and biological characteristics. High capital expenses, manufacturing costs, and a paucity of some well-scalable methods, all of which lead to low BNC output in commercial scale, are major barriers that must be addressed. Advances in production methods, including bioreactor technologies, static intermittent, and semi-continuous fed batch technologies, and innovative outlay substrates, may be able to overcome the challenges to BNC production at the industrial scale. The novelty of this review is that it highlights genetic modification possibilities in BNC production to overcome existing impediments and open up viable routes for large-scale production, suitable for real-world applications. This review focuses on various production routes of BNC, its properties, and applications, especially the major advancement in food, personal care, biomedical and electronic industries.

Enhanced production of prodigiosin by Serratia marcescens UCP 1549 using agrosubstrates in solid-state fermentation.

This work aimed to investigate the production of prodigiosin by S. marcescens UCP 1549 in solid-state fermentation (SSF), as a sustainable alternative for reducing the production costs and environmental impact. Thus, different agro-industrial substrates were used in the formulation of the prodigiosin production medium, obtaining the maximum yield of pigment (119.8 g/kg dry substrate) in medium consisting of 5 g wheat bran, 5% waste soybean oil and saline solution. The pigment was confirmed as prodigiosin by the maximum absorbance peak at 535 nm, Rf 0.9 in TLC, and the functional groups by infrared spectrum (FTIR). Prodigiosin demonstrated stability at different values of temperature, pH and NaCl concentrations and antimicrobial properties, as well as not show any toxicity. These results confirm the applicability of SSF as a sustainable and promising technology and wheat bran as potential agrosubstrate to produce prodigiosin, making the bioprocess economic and competitive for industrial purposes.

Rhamnolipid production by Pseudomonas aeruginosa grown on membranes of bacterial cellulose supplemented with corn bran water extract.

Surfactants represent a billionaire market of amphiphilic molecules with worldwide applications in almost every branch of modern industry. The most common surfactants, available and currently used, are chemically produced. However, there is an urge to replace these chemical compounds with those obtained by mild and green technologies such as microbial biosurfactants produced by fermentative processes. Rhamnolipids are glycolipid biosurfactants that present highly effective surface-active properties and enormous market potential; nevertheless, their production costs remain not competitive. Here, we present a process of rhamnolipid production by static submerged cultivation using membranes of bacterial cellulose as substrate. The mixture of the rhamnolipid congeners was characterized showing effective surface-active properties and high amount of di-rhamnolipids (95.6%). Through this fermentative technology, 15.8 g/L of rhamnolipid was reach using a very simple and low-cost medium. The present process might decrease biosurfactant production cost, avoid foam formation, and finally make rhamnolipid production more viable.

Surface Film Formation in Static-Fermented Rice Vinegar: A Case Study.

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0-3.3 and 3.0-8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ∼1 × 2 µm in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

Surface Film Formation in Static-Fermented Rice Vinegar: A Case Study

In the present study, we aimed to determine the cause of surface film formation in three rice vinegars fermented using the traditional static fermentation method. The pH and total acidity of vinegar were 3.0–3.3 and 3.0–8.7%, respectively, and acetic acid was the predominant organic acid present. Colonies showing a clear halo on GYC medium were isolated from the surface film of all vinegars. Via 16S rDNA sequencing, all of the isolates were identified as Acetobacter pasteurianus. Furthermore, field-emission scanning electron microscopy analysis showed that the bacterial cells had a rough surface, were rod-shaped, and were ∼1 × 2 µm in size. Interestingly, cells of the isolate from one of the vinegars were surrounded with an extremely fine threadlike structure. Thus, our results suggest that formation of the surface film in rice vinegar was attributable not to external contamination, to the production of bacterial cellulose by A. pasteurianus to withstand the high concentrations of acetic acid generated during fermentation. However, because of the formation of a surface film in vinegar is undesirable from an industrial perspective, further studies should focus on devising a modified fermentation process to prevent surface film formation and consequent quality degradation.

Production of bacterial cellulose from Komagataeibacter saccharivorans strain BC1 isolated from rotten green grapes.

Bacterial cellulose (BC) is one of the prominent biopolymers that has been acquiring attention currently due to its distinctive properties and applications in various fields. The current work presents the isolation of Komagataeibacter saccharivorans strain BC1 isolated from rotten green grapes, followed by biochemical and genotypic characterization, which confirmed that the strain is capable of synthesizing cellulose. Further, production media was designed and certain variables such as carbon, nitrogen sources, pH, and temperature were optimized in order to obtain the maximum concentration of cellulose production. We found mannitol to be the ideal carbon source and yeast extract as the ideal nitrogen source with a highest BC dry yield of 1.81 ± 0.25 g/100 mL at pH 5.76 for a week at 30 °C.The charcterization of pellicles by FTIR spectrum depicted similar functional groups present in synthesized BC as that of the commercial cellulose. X-ray diffraction revealed that BC showed 82% crystallinity. Surface morphology of the dried pellicle was studied by SEM image which showed that the BC surface was tightly packed with thin fibers with less porosity. Hence the study demonstrates that the isolates of K.saccharivorans could be used to produce a biopolymer in a short period of time using a modified production medium.

Effect of fermentation modes on nutritional and volatile compounds of Huyou vinegar.

Semi-solid static mode was applied to brew Huyou (Citrus changshanensis) vinegar, called HV-SS, and changes of main nutrients, volatile compounds and antioxidant capacity at different brewing stages, i.e. Huyou puree (HP), Huyou wine (HW) and HV-SS, were investigated. Meanwhile, all these parameters of HV-SS and Huyou vinegar brewed by liquid static mode (HV-LS) were compared. The contents of the main nutrients except for vitamin C (Vc) and reducing sugar increased significantly after fermentation from HP to HV-SS. DPPH radical-scavenging capacity and reducing power of HW was the highest and ABTS+ scavenging capacity of HV-SS was the highest. Acids, flavonoids, phenolics and Vc jointly played important roles in the antioxidant capacity of HV-SS. Forty-six aroma compounds were detected in HP and alcohols were the principal components (15 alcohols accounted for 46.2%). During HW fermentation, most of the compounds in HP (d-limonene, hexanal, hexanol and 3-hexen-1-ol) were nearly disappeared, and some new alcohols, esters and alkanes were formed, being the abundant compounds in HW and accounting for 62.99%, 18.44% and 10.52% respectively. There were 51 aroma compounds detected in HV-SS and 10 more than those in HV-LS. The types or contents of esters (22.13%), acids (50.49%) and aldehydes (7.33%) in HV-SS were markedly different from those in HP, HW and HV-LS, giving the unique aroma and good flavor to HV-SS. Therefore, semi-solid static fermentation mode was more suitable for brewing Huyou vinegar on the aspect of balancing the nutrients characteristics and flavor compounds formation.

Effect of Different Carbon Sources on Bacterial Nanocellulose Production and Structure Using the Low pH Resistant Strain Komagataeibacter Medellinensis.

Bacterial cellulose (BC) is a polymer obtained by fermentation with microorganism of different genera. Recently, new producer species have been discovered, which require identification of the most important variables affecting cellulose production. In this work, the influence of different carbon sources in BC production by a novel low pH-resistant strain Komagataeibacter medellinensis was established. The Hestrin-Schramm culture medium was used as a reference and was compared to other media comprising glucose, fructose, and sucrose, used as carbon sources at three concentrations (1, 2, and 3% w/v). The BC yield and dynamics of carbon consumption were determined at given fermentation times during cellulose production. While the carbon source did not influence the BC structural characteristics, different production levels were determined: glucose > sucrose > fructose. These results highlight considerations to improve BC industrial production and to establish the BC property space for applications in different fields.