Kitchen Waste as a Novel Available Substrate for Prodigiosin Production bySerratia Marcescense

Recent Advances in Prodigiosin as a Bioactive Compound in Nanocomposite Applications

Bionanocomposites based on natural bioactive entities have gained importance due to their abundance; renewable and environmentally benign nature; and outstanding properties with applied perspective. Additionally, their formulation with biological molecules with antimicrobial, antioxidant, and anticancer activities has been produced nowadays. The present review details the state of the art and the importance of this pyrrolic compound produced by microorganisms, with interest towards Serratia marcescens, including production strategies at a laboratory level and scale-up to bioreactors. Promising results of its biological activity have been reported to date, and the advances and applications in bionanocomposites are the most recent strategy to potentiate and to obtain new carriers for the transport and controlled release of prodigiosin. Prodigiosin, a bioactive secondary metabolite, produced by Serratia marcescens, is an effective proapoptotic agent against bacterial and fungal strains as well as cancer cell lines. Furthermore, this molecule presents antioxidant activity, which makes it ideal for treating wounds and promoting the general improvement of the immune system. Likewise, some of the characteristics of prodigiosin, such as hydrophobicity, limit its use for medical and biotechnological applications; however, this can be overcome by using it as a component of a bionanocomposite. This review focuses on the chemistry and the structure of the bionanocomposites currently developed using biorenewable resources. Moreover, the work illuminates recent developments in pyrrole-based bionanocomposites, with special insight to its application in the medical area.

Prodigiosin: a promising biomolecule with many potential biomedical applications

Pigments are among the most fascinating molecules found in nature and used by human civilizations since the prehistoric ages. Although most of the bio-dyes reported in the literature were discovered around the eighties, the necessity to explore novel compounds for new biological applications has made them resurface as potential alternatives. Prodigiosin (PG) is an alkaloid red bio-dye produced by diverse microorganisms and composed of a linear tripyrrole chemical structure. PG emerges as a really interesting tool since it shows a wide spectrum of biological activities, such as antibacterial, antifungal, algicidal, anti-Chagas, anti-amoebic, antimalarial, anticancer, antiparasitic, antiviral, and/or immunosuppressive. However, PG vehiculation into different delivery systems has been proposed since possesses low bioavailability because of its high hydrophobic character (XLogP3-AA = 4.5). In the present review, the general aspects of the PG correlated with synthesis, production process, and biological activities are reported. Besides, some of the most relevant PG delivery systems described in the literature, as well as novel unexplored applications to potentiate its biological activity in biomedical applications, are proposed.

High-level production of microbial prodigiosin: A review

Prodigiosin is a natural red pigment derived primarily from secondary metabolites of microorganisms, especially Serratia marcescens. It can also be chemically synthesized. Prodigiosin has been proven to have antitumor, antibacterial, antimalaria, anti-insect, antialgae, and immunosuppressive activities, and is gaining increasing important in the global market because of its great potential application value in clinical medicine development, environmental treatment, preparation of food additives, and so on. Due to the low efficiency of prodigiosin chemical synthesis, high-level prodigiosin of production by microorganisms are necessary for prodigiosin applications. In this paper, the production of prodigiosin by microorganism in recent decades is reviewed. The methods and strategies for increasing the yield of prodigiosin are discussed from the aspects of medium composition, additives, factors affecting production conditions, strain modification, and fermentation methods.

Ecological and Biotechnological Aspects of Pigmented Microbes: A Way Forward in Development of Food and Pharmaceutical Grade Pigments

Microbial pigments play multiple roles in the ecosystem construction, survival, and fitness of all kinds of organisms. Considerably, microbial (bacteria, fungi, yeast, and microalgae) pigments offer a wide array of food, drug, colorants, dyes, and imaging applications. In contrast to the natural pigments from microbes, synthetic colorants are widely used due to high production, high intensity, and low cost. Nevertheless, natural pigments are gaining more demand over synthetic pigments as synthetic pigments have demonstrated side effects on human health. Therefore, research on microbial pigments needs to be extended, explored, and exploited to find potential industrial applications. In this review, the evolutionary aspects, the spatial significance of important pigments, biomedical applications, research gaps, and future perspectives are detailed briefly. The pathogenic nature of some pigmented bacteria is also detailed for awareness and safe handling. In addition, pigments from macro-organisms are also discussed in some sections for comparison with microbes.

Optimization of prodigiosin biosynthesis by Serratia marcescens using unconventional bioresources

BACKGROUND

Prodigiosin is a naturally occurring red pigment by Serratia marcescens and having enormous medicinal properties. Recently, there is a need to develop a high-throughput and economically feasible bioprocess for the production of prodigiosin. In order to find a cost-effective alternative to individual fatty acids as substrate in industries, we tried to study the effect of different fatty acid containing oil seed cakes of peanut, sesame, and mustard as sources of substrate. The present study screened waste and unconventional bioresources for the production of prodigiosin using S. marcescens ATCC 13880. Sources with high oil content were screened for maximum production of prodigiosin. Also, various parameters like temperature, pH, and nutrient precursors were screened and optimized for the production of prodigiosin.

RESULTS

Scaled-up of optimized media consisting of 4% peanut oil seed cake powder, 2% sucrose, pH 7.5, temperature 28 °C, and 72 h incubation time resulted in highest production of 15.5 g/L wet biomass and 0.9 g/L of dried prodigiosin. Further, UV scan of the pigment showed maximum absorbance at 538 nm which is physiological property of the pigment. Extraction and purification of the pigment at the commercial level using the chromatographic techniques and mass spectral analysis confirmed the presence of prodigiosin.

CONCLUSION

Using oil-extraction leftover wastes might help in the commercial and cost-effective production of prodigiosin.