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Bacteriocin is a proteinaceous biomolecule produced by bacteria (both Gram-positive and Gram-negative) that exhibits antimicrobial activity against closely related species, and food-borne pathogens. It has recently gained importance and attracted the attention of several researchers looking to produce it from various substrates and bacterial strains. This ushers in a new era of food preservation where the use of bacteriocin in food products will be an alternative to chemical preservatives, and heat treatment which are understood to cause unwanted side effects, and reduce sensory and nutritional quality. However, this new market depends on the success of novel downstream separation schemes from various types of crude feedstocks which are both effective and economic. This review focuses on the downstream separation of bacteriocin from various sources using both conventional and novel techniques. Finally, recommendations for future interesting areas of research that need to be pursued are highlighted.

Aqueous micellar two‐phase system (AMTPS) is an extractive technique of biomolecule, where it is based on the differential partitioning behavior of biomolecule between a micelle‐rich and a micelle‐poor phase. In this study, an AMTPS composed of a nonionic surfactant, Triton X‐100 (TX‐100) was used for purifying a bacteriocin‐like inhibitory substance (BLIS) derived from Pediococcus acidilactici Kp10. The influences of the surfactant concentration and the effect of additives on the partitioning behavior and activity yield of the BLIS were investigated. The obtained coexistence curves showed that the mixtures of solutions composed of different surfactant concentrations (5–30% w/w) and 50% w/w crude load were able to separate into two phases at temperatures of above 60 °C. The optimum conditions for BLIS partitioning using the TX‐100‐based AMTPS were: TX‐100 concentration of 22.5% w/w, CFCS load of 50% w/w, incubation time of 30 min at 75 °C, and back‐extraction using acetone precipitation. This optimal partitioning resulted in an activity yield of 64.3% and a purification factor of 5.8. Moreover, the addition of several additives, such as sorbitol, KCl, dioctyl sulfosuccinate sodium salt, and Coomassie® Brilliant Blue, demonstrated no improvement in the BLIS separation, except for Amberlite® resin XAD‐4, where the activity yield was improved to 70.3% but the purification factor was reduced to 2.3. Results from this study have demonstrated the potential and applicability of TX‐100‐based AMTPS as a primary recovery method for the BLIS from a complex fermentation broth of P. acidilactici Kp10. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2719, 2019

Ficus deltoidea is a popular traditional medicine that widely used to treat various kind of diseases because of its high number of phenolic contents. In order to meet the demand of the high usage in the market, it is very important to study the behaviour of the dried herbal leaves to prolong the shelf life during storage. Hence, the study of moisture adsorption isotherm is one of the crucial parameters to minimize the deterioration of the quality. The moisture adsorption data of dried Ficus deltoidea leaves were monitored using gravimetric static method. Six different saturated salts such as potassium chloride, sodium chloride, sodium nitrate, magnesium nitrate, magnesium chloride and potassium acetate were utilized in this experiment. The equilibrium relative humidity range was setup between 23 to 86 %. Three different temperatures of 8, 30, 40 °C were used as a treatment of experiment. From the final results, it is clearly claimed that the moisture adsorption isotherm data exhibited J shaped and type III of Brunauer, Emmet and Teller (BET) classification. In addition, the results of experimental data as shown that the best mathematical model fitted to Peleg model compared to GAB and Oswin models.

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