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The purpose of this paper was to identify Serratia marcescens to extract and purify prodigiosin pigment to evaluate the antibacterial potential of the pigment.

Samples were collected from shrimp aquaculture ponds. Species identification was conducted using morphological, biochemical and molecular tests. Pigment extraction and purification were carried out using column chromatography. The antibacterial effect of crude and purified prodigiosin pigment was evaluated on Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus as biofouling bacteria. In addition, the interaction between prodigiosin and proteins involved in biofilm formation was evaluated using molecular docking.

The results of prodigiosin extraction with solvents showed the highest percentage of pigment presence with methanol solvent in the second day of culture. The chemical structure of pure prodigiosin obtained from the column chromatography was confirmed by Fourier-transform infrared spectroscopy. Both crude and purified pigments exhibited antibacterial effects against selected bacterial strains. The antibacterial effect of the purified pigment was higher, and the highest antibacterial effect was observed on B. subtilis. Prodigiosin docking was carried out with all target proteins, and the docked energy in all of them was at an acceptable level.

Prodigiosin extracted from S. marcescens can be used as a bioactive compound to design and manufacture of anti-biofouling and anti-biofilm formation products to use extensively for industrial applications as a natural color in marine industries, food industry, cosmetics and textile productions.

Whey is a by-product of paneer, cheese and casein industry and considered as a dairy waste. Worldwide, approximately 180–1,900 million tons of whey is produced annually. Whey is classified as a high pollutant due to its organic matter level. Owing to its high chemical oxygen demand and biological oxygen demand, it is a big threat to the environment. Whey contains 4.5%–5.0% lactose, 0.6%–0.7% protein, 0.4%–0.5% lipids, vitamins and minerals. Due to its high nutritional profile, it is a good substrate for the microorganisms for production of natural pigments. The purpose of this paper is to review the utilization of low cost substrate (whey) for production of various types of pigments and their applications in different sectors.

The databases for the search included: Scopus, PubMed, Science Direct, Web of Science, Research gate and Google. The main search was directed towards different types of natural pigments, stability, technologies for enhancing their production and contribution towards circular economy. Approximately 100 research papers were initially screened. A global search was conducted about natural pigments. Research articles, review papers, books, articles in press and book chapters were the type of search for writing this review paper.

Production of natural pigments using whey and their addition in food products not only improves the colour of food but also enhances the antioxidant properties of food products, helping the health benefits by chelating free radicals from the body. The sustainable use of whey for production of natural pigments can improve the bio-based economy of different industries and thereof the national economy.

Efficient utilization of whey can bring a lot more opportunities for production of natural pigments in a sustainable manner. The sustainable approach and circular economy concepts will benefit the dependent industries and health conscious consumers. The potential uses of whey for the production of natural pigments using diverse organisms are highlighted in this paper.

White maize-based porridge is a staple food for about 80 per cent consumers in South Africa and in other sub-Saharan African countries contributing significantly to the diet of rural population in developing countries. White maize is deficient in some amino acids and over-dependency on its porridge may lead to high prevalence of malnutrition-related health conditions. Moringa oleifera (MO) and termite (Macrotermes falciger) are known to contain substantial amount of protein. The purpose of this study was to determine the effect of powders from MO leaves and termite on the nutritional and sensory properties of instant maize porridge.

Inclusion of MO and termite powder in instant maize porridge, using different treatments were considered using a completely randomised design. Factor levels were control (maize flour) cooked, blanched and uncooked MO samples. Data were analysed using SPSS version 23.

Protein content of fortified instant maize porridge (FMP) significantly increased from 10.0 to 21.2 per cent compared to unfortified porridge, and this could be attributed to the substitution effect, as fresh uncooked MO leaves are reported to be high in protein. Mineral content of FMP was higher in zinc, iron, calcium and magnesium. Calcium values of FMP were higher (276.8 mg/100 g) compared to unfortified porridge (7.1 mg/100 g). Upon the addition of MO leaves and termite powder, the zinc content increased from 3.4 mg/100to 7.6 mg/100 g. Higher iron values (27.9-36.9 mg/100 g) were observed among fortified samples. The sensory result showed that control sample had higher acceptance than the fortified samples (p = 0.02). Sensory analysis showed that among fortified porridges, blanched sample was rated high for colour and texture, cooked sample was higher in taste and uncooked sample was higher for aroma. Control sample had higher acceptance than fortified porridges for taste. The results of this study showed that the addition of MO leaves and termite powder to instant maize porridge has led to a substantial increase in the nutritional value of FMP.

This study was carried out to develop instant maize porridge fortified with MO leaves and termite powder suitable for infants, pregnant mothers and other maize consumers. The author aimed at improving the nutritional content of instant maize porridge by combining it with MO leaves and termite powders. The results showed that the addition of MO leaves and termite powders to instant maize porridge has led to a substantial increase in the nutritional value of FMP. Therefore, powder from MO leaves and termites could be used in complementary foods to increase protein and mineral contents.

This study aims to explore the synthesis, characteristics and utilization of polymer composites integrated with cutting-edge pigments.

The incorporation of advanced pigments introduces functionalities such as enhanced mechanical strength, thermal stability, ultraviolet resistance and color stability, thus extending the range of applications in diverse fields including automotive, aerospace, electronics and construction.

This review discusses the mechanisms underlying the property enhancements achieved through the incorporation of advanced pigments and highlights recent developments in the field.

Polymer composites incorporating advanced pigments have garnered significant attention in recent years because of their potential to enhance various material properties and broaden their applications. This paper explores the fabrication methods of polymer composites reinforced with organic/inorganic advanced pigments in brief along with their characteristics and applications.

Carotenoids are pigments that have significant value as colorants and antioxidants in pharmaceutical, food, textile and cosmetic industries. Owing to its high demand, this study aims to identify ß-carotene producing bacteria from different terrestrial habitats of Jaipur region.

In this paper, standard isolation and purification process was used, followed by colony morphology and biochemical characterization of ß-carotene producing bacteria. ß-carotene concentration was determined quantitatively using spectrophotometric method.

Out of 43 isolates, 21 isolates showed peak range between 400 and 500 nm confirming the presence of carotenoids. Only one bacteria SAN-A has capacity to produce ß-carotene confirmed by the thin layer chromatography and high performance liquid chromatography (HPLC) with a yield of 1.68 mg/l. The 2, 2-Diphenyl-2-picrylhydrazil (DPPH) assay showed an IC50 value of 4.0 mg/ml.

The present study revealed the presence of ß-carotene producing bacteria in the soil of different terrestrial habitat of Jaipur region which can be exploited as an economical source for ß-carotene production.

This study aims to synthesize new disperse dyes based on novel pyrazolyl quinolinone derivatives EQ1 and EQ2 and evaluate their characteristics after dyeing them on a polyester fabric.

New dispersed dyes based on pyrazolyl quinolinone derivatives were prepared and confirmed by different analyses, such as infrared spectroscopy, elemental microanalysis and nuclear magnetic resonance spectroscopy. They were dyed on a polyester fabric. The characteristics of dyed polyester were determined by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength. The electronic structures of EQ1 and EQ2 in gaseous state were investigated using density functional theory/B3LYP/6-311++G (d, p) level of theory.

The suitability of the prepared dyestuffs for dyeing on polyester fabrics has been investigated. The study was concerned with comparing the contrasting depth of shade and levelness. The study was concerned mainly with dye uptake and color measurements at two different temperatures. The results showed that the exhaustion values of dyes inside the polyester at 130°C were higher than those obtained at conventional dyeing temperature (100°C). The exhaustion values of EQ2 were greater than those of EQ1 at 130°C with 2.2%, while the brightness of EQ2 was higher than that of EQ1 at the two investigated temperatures. The results of molecular orbital calculations show that the studied compounds are planar. In addition, the ionization potential of EQ1 was lower than that of EQ2. The results of the theoretical study helped in understanding the dyeing behavior of the investigated azo dyes.

The prepared disperse dyes based on pyrazolyl quinolinone derivatives could be used in textile dyeing of polyester on an industrial scale.

The purpose of this study is to modify the FDM 3D printer to print with polystyrene (PS) microspheres as the printing material, thus enabling bottom-up structural color printing and evaluating structural color printing.

This study chose a range of different heated bed temperatures to determine a suitable temperature for accelerating the self-assembly of photonic crystals and printing structural colors on various substrates. In addition, this study enhanced the structural color by doping PS microspheres with different contents of Acid Black 210 dye and evaluated the color-enhanced structural color by eye and spectrophotometer under different light sources.

The results show that the modified 3D printer can be used for structural color printing, and 50°C is determined as the heated bed temperature. There are significant differences in structural colors when printing under different color backgrounds and material substrates, and corresponding suitable substrates should be selected according to the application. The doping of PS microspheres with varying contents of dye results in different color levels of structural color. As with pigment colors, the visual perception of structural color varies when viewed under different light sources.

This paper proposes to print structural colors low-costly, analyze structural colors under substrate and light source conditions, and expand the structural color gamut by enhancing structural colors, which has positive implications for further research on structural colors as printing colors.

This study aims to show the dyeing behaviour of polyester fabrics using four novel heterocyclic disperse dyes.

The four dyes were synthesized based on 5, 5'-(1, 4-phenylene) bis (1, 3, 4-thiadiazol-2-amine) as a diazonium compound. The UV/Vis absorption spectroscopic data of these disperse dyes while dyeing polyester fabrics were investigated. Following this, the dyeing properties of these dyes on polyester fabrics were investigated under acid condition.

The results showed that increasing the dyeing temperature from 80°C to 100°C led to an increase in dye uptake for all dyes, but further increases of the temperature to 130°C led to higher dye uptake for dye 3 as the dye exhaustion increased by about 50% from 55.9% to 91.4%.

This study is important as it introduces new dyes for the dyeing of polyethylene terephthalate (PET) fibres with colours that range from yellowish orange to bluish yellow and scarlet red and all with excellent brightness, levelness and depth of shade.

This paper aims to extract colour from micro-organisms (as a source of natural pigments) using agro-industrial substrates to replace synthetic media by solid state fermentation. Nature is filled with colours. Due to health and environmental consciousness among people, use of synthetic colour has declined, and so the need to develop colour from cheap and easily available natural sources (plants, animals, micro-organisms and algae) using a cost-effective technique with higher yield and rapid growth. Monascus purpureus colour is a potent source of compounds (Dimerumic acid, Monacolin-k and -aminobutyric acid) having antimutagenic, antimicrobial and antiobesity, which helps in combating diseases.

Response surface methodology was used to optimise the biopigments extraction from Monascus purpureus using solid state fermentation.

The best optimised conditions for biopigments production using Monascus purpureus MTCC 369 were pH 5.4 at 32°C for 8 days 9 hours (8.9 days) from sweet potato peel and pea pod powder, 7.8 (w/w) and 3.9 per cent (w/w), respectively, which gave a final yield of 21 CVU/g. The model F-value of 69.18 and high value of adjusted determination coefficient 96.00 per cent implies high level of significance of the fitted model.

Extracted colour can be used in beverages, confectionery and pharmaceutical industries.

Colour produced using Monascus purpureus MTCC 369 is a natural source. As consumers are reluctant to use synthetic colour because of the undesirable allergic reactions caused by them, so a biopigment produced is natural colouring compound with wide application in food sector.

Selected sources of carbon and nitrogen were not used earlier by any researcher to extract biopigment from Monascus purpureus MTCC 369.

Biopigments, natural colors from microbiological origin are of great interest because of their potential advantages over synthetic colorants. Therefore, this paper aims to evaluate the best possible fermentative conditions for the maximum production of biopigment using solid state fermentation and submerged fermentation by Monascus purpureus MTCC 369.

The biopigment was produced using solid state fermentation and submerged with optimized substrate to achieve higher yield. The statistical analysis was carried out using a Microsoft Excel ® (Microsoft Corporation).

On comparative analysis, it was observed that solid state fermentation resulted significant accumulation of biopigment (9.0 CVU/g) on the 9th day in comparison to submerged fermentation (5.1 CVU/g) on the 15th day.

Results revealed that sweet potato peel powder and pea pods provides necessary nutrients required for mycelial growth, and biopigment production, therefore, can be used as potent substrate for biopigment production by Monascus purpureus MTCC 369. Extracted color can be used in confectionery, beverages and pharmaceutical industries.

This work focuses on utilisation of waste for production of pigment as alternative source to synthetic colorant, and few studies have been carried out using wastes, but no work has been carried out on sweet potato peel to the best of the authors’ knowledge.