Development of the yeast and lactic acid bacteria co-culture agent for atmospheric ammonia removing: Genomic features and on-site applications.

Odorous gas (e.g. atmospheric ammonia) in low ventilation public places, such as public toilets and waste transfer stations, causes severe health problems. Many technologies are developed to purify the atmospheric ammonia, among which the microbial agents are supposed to be a green and economical approach. In this study, we developed a yeast, Pichia sp. J1, and a lactic acid bacterium (LAB), Lactobacillus paracasei B1, co-culture agent for atmospheric ammonia removing. The on-site application results indicated the yeast and LAB mixed fermented agent had a maximum ammonia removing efficiency of 98.78%, which is significantly higher than the pure cultures (78.93% for B1 and 75.00% for J1), indicating the co-culture agent is an excellent biological product for ammonia removal. The excellent performance of the agent is closely related to the synergy behaviors between the yeast and LAB. In the co-culture agents, some of the LAB cells adhered closely to the yeast, and the growth and lactic acid producing ability of LAB were significantly promoted by yeast. Genomic analysis indicated the complementary of nutrients, i.e. carbon and nitrogen resources, signal transduction, and adhesion proteins (regulates adhesion behavior) played roles in regulating the synergy effects. Our study offers a novel biological solution of odorous gas purification.

A Novel Bio-Purification Process Employing an Engineered E. coli Strain for Downstream Processing of Lactic Acid Solutions from the Fermentation of Agro-Industrial by-Products.

This study aims to integrate a novel bio-purification process employing an engineered E. coli strain in the downstream processing of lactic acid (LA) fermentation broths from low-cost renewable biological feedstocks. Fermentation broth of candy waste and digestate mixture was used as a real biological feedstock. An engineered E. coli strain that selectively catabolize impurities without catabolizing LA was initially adapted on the biological feedstock, followed by shake flask experiments to prove the bio-purification concept. Scale-up and validation in a bench-scale bioreactor followed, before developing a semi-continuous membrane bioreactor (MBR) bio-purification process. The MBR bio-purification was assessed with biological feedstocks which simulated ultrafiltration or nanofiltration permeates. Incomplete removal of impurities and increased fouling was observed in the case of the ultrafiltration permeate. Contrarily, the nanofiltration permeate was successfully treated with MBR bio-purification, since low membrane fouling, 100% maltose and acetic acid removal, and no LA catabolism was achieved. MBR bio-purification as a post-treatment step in the downstream processing of LA was demonstrated as a promising technology for increasing the purity of LA solutions.

Development of a hybrid bio-purification process of lactic acid solutions employing an engineered E. coli strain in a membrane bioreactor.

BACKGROUND: A potential alternative to lactic acid production through sugar fermentation is its recovery from grass silage leachate. The separation and purification of lactic acid from fermentation broths remain a key issue, as it amounts to up to 80% of its industrial production cost. In this study, a genetically engineered E. coli strain (A1:ldhA), that cannot catabolize lactic acid, has been used to selectively remove impurities from a synthetic medium comprising typical components (i.e., glucose and acetic acid) of green grass silage leachate. A systematic approach has been followed to provide a proof-of-concept for a bio-purification process of lactic acid solutions in a membrane bioreactor operating in semi-continuous mode. RESULTS: The synthetic medium composition was initially optimized in shake-flasks experiments, followed by scale-up in bench-scale bioreactor. Complete (i.e., 100%) and 60.4% removal for glucose and acetic acid, respectively, has been achieved in batch bioreactor experiments with a synthetic medium comprising 0.5 g/L glucose and 0.5 g/L acetic acid as carbon sources, and 10 g/L lactic acid; no lactic acid catabolism was observed in all batch fermentation tests. Afterwards, a hybrid biotechnological process combining semi-continuous bioreactor fermentation and ultrafiltration membrane separation (membrane bioreactor) was applied to in-situ separate purified medium from the active cells. The process was assessed under different semi-continuous operating conditions, resulting in a bacteria-free effluent and 100% glucose and acetic acid depletion, with no lactic acid catabolism, thus increasing the purity of the synthetic lactic acid solution. CONCLUSIONS: The study clearly demonstrated that a bio-purification process for lactic acid employing the engineered E. coli strain cultivated in a membrane bioreactor is a technically feasible concept, paving the way for further technological advancement.

Clinical trial on different dose patterns of Shodhanartha Abhyantara Snehana.

Internal oleation (Snehana) is a major preparatory procedures performed before Bio-Purification (Shodhana). Oleation leads and decides the total outcome of the Bio-purification therapy; hence, standard guidelines are needed for performing the internal oleation in an effective manner and also for avoiding the inadequate and excess oleation. It is obligatory to start and increase the dose of lipids (Sneha) in appropriate and judicious way considering the bio-fire (Agni) and nature of bowel habit (Koshtha) of the subject. The outcome of Bio-Purification depends upon proper mobilization of Dosha from the periphery (Shakha) to gastrointestinal tract (Koshtha); which is achieved with the help of oleation therapy (Snehana Karma) and sudation therapy (Svedana Karma). This clinical study was carried out on 29 subjects to standardize the dose and duration of internal oleation and to develop the oleation grade for the assessment of internal oleation therapy. The selected subjects were randomly divided into two groups, in which group A was given fixed increase dose of ghee and in group B non-fixed increase dose was given. Results of this study show that the total percentage of oleation was 33.57% in group A and it was 45.28% in group B. Subjects of Group B (non-fixed dose schedule) have shown better oleation in all the aspects, i.e. duration, oleation grade, and purification grade.