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Natural plant pigments are safe and have low toxicity, with various nutrients and biological activities. However, the extraction, preservation, and application of pigments are limited due to the instability of natural pigments. Therefore, it is necessary to examine the extraction and application processes of natural plant pigments in detail. This review discusses the classification, extraction methods, biological activities, and modification methods that could improve the stability of various pigments from plants, providing a reference for applying natural plant pigments in the industry and the cosmetics, food, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Synthetic dyes and colourants have been the mainstay of the pigment industry for decades. Researchers are eager to find a more environment friendly and non-toxic substitute because these synthetic dyes have a negative impact on the environment and people's health. Microbial pigments might be an alternative to synthetic pigments. Microbial pigments are categorized as secondary metabolites and are mainly produced due to impaired metabolism under stressful conditions. These pigments have vibrant shades and possess nutritional and therapeutic properties compared to synthetic pigment. Microbial pigments are now widely used within the pharmaceuticals, food, paints, and textile industries. The pharmaceutical industries currently use bacterial pigments as a medicine alternative for cancer and many other bacterial infections. Their growing popularity is a result of their low cost, biodegradable, non-carcinogenic, and environmentally beneficial attributes. This audit article has made an effort to take an in-depth look into the existing uses of bacterial pigments in the food and pharmaceutical industries and project their potential future applications. [ABSTRACT FROM AUTHOR]

Pollution from the international dye industry continues to be a global problem. Biotechnology offers new options, including a closer look at select wood decay fungi to replace inorganic dyes. The pigments produced by a small group of soft rotting fungi are generally naphthoquinonic and remarkably stable. From this group, the dramada crystals, produced by Scytalidium cuboideum, are of particular interest. To test the application of this pigment as a natural colorant of cellulosic pulps, four different bleached pulps were selected (one hardwood, three softwood), in three different mediums (acetone, ethanol, and DI water). The pigment generated a significant change of color, but there was no significant difference in color intensity based on the solvent carrier. These preliminary results are promising as they open the door for further exploration of applications of fungal pigments in the paper industry. Once these pigments can be reliably grown, they will offer a sustainable organic alternative to polluting inorganic dyestuffs and help reduce the toxic effluent released into the soil and waterways. [ABSTRACT FROM AUTHOR]

Bagasse ash (BA) and rice husk ash (RHA) are by-products from electricity power plants. Ground calcium carbonate waste (GCW) is the by-product of the mining of calcium carbonate (CaCO3) in the color pigment manufacturing industry. Both BA and RHA are classified as low-quality pozzolanic materials, differing from GCW, which contains a high calcium oxide (CaO) content that leads to products equivalent to the hydration reaction. Therefore, GCW is likely able to improve the properties of self-consolidating concrete (SCC) incorporating BA and RHA. This paper discusses the production of green self-consolidating concrete (gSCC) and identifies the benefit of using GCW in gSCC prepared by triple combined GCW (10 and 20 wt%), BA (10, 20, and 30 wt%), and RHA (20 wt%). The results indicate that the majority of the gSCC retain acceptable flowability. The differences in the levels of gSCC substitution and the V-funnel flow results show general correlations with the increase in GCW. The gSCC prepared by 10 wt% GCW associated with 10 wt% BA and 20 wt% RHA was improved significantly. The filling and passing abilities of the gSCC were improved by using GCW. In addition, gSCC achieved mechanical property development and was able to minimize the consumption of OPC by up to 40%. [ABSTRACT FROM AUTHOR]

This study was focused on the historical evolution of the waste management policy carried out by the Spanish industry devoted to titanium dioxide pigments manufacturing for minimising its environmental impact. This challenge was achieved by modifying the original chemical process and converting the originally dissolved sulphate and sulphuric acid present in the final streams of the factory into sulphate minerals (melanterite FeSO4·7H2O, szomolnokite FeSO4·H2O, and gypsum CaSO4·2H2O). These by-products were physicochemically, mineralogically and radiologically characterised in order to gain basic information for its subsequent commercial use. Some of the uses summarised in this study for both ferrous sulphates are as a supplier of iron to prevent chlorosis, animal food, manufacture of cement (to reduce Cr VI), primary flocculants for ferrous sulphates, magnetite nanoparticle and nano-Fe2O3 formation, production of magnetite concentrate, remediation of polluted soils with metals, and treatment of wastewaters. Red gypsum was analysed as a substitute for natural gypsum in the manufacture of cement, construction materials, inhibitor in soil erosion, and the immobilisation of heavy metals in agricultural soils and carbonation processes. [ABSTRACT FROM AUTHOR]

Marine bacterial species contribute to a significant part of the oceanic population, which substantially produces biologically effectual moieties having various medical and industrial applications. The use of marine-derived bacterial pigments displays a snowballing effect in recent times, being natural, environmentally safe, and health beneficial compounds. Although isolating marine bacteria is a strenuous task, these are still a compelling subject for researchers, due to their promising avenues for numerous applications. Marine-derived bacterial pigments serve as valuable products in the food, pharmaceutical, textile, and cosmetic industries due to their beneficial attributes, including anticancer, antimicrobial, antioxidant, and cytotoxic activities. Biodegradability and higher environmental compatibility further strengthen the use of marine bio-pigments over artificially acquired colored molecules. Besides that, hazardous effects associated with the consumption of synthetic colors further substantiated the use of marine dyes as color additives in industries as well. This review sheds light on marine bacterial sources of pigmented compounds along with their industrial applicability and therapeutic insights based on the data available in the literature. It also encompasses the need for introducing bacterial bio-pigments in global pigment industry, highlighting their future potential, aiming to contribute to the worldwide economy. [ABSTRACT FROM AUTHOR]

The public's demand for natural, eco-friendly, and safe pigments is significantly increasing in the current era. Natural pigments, especially fungal pigments, are receiving more attention and seem to be in high demand worldwide. The immense advantages of fungal pigments over other natural or synthetic pigments have opened new avenues in the market for a wide range of applications in different industries. In addition to coloring properties, other beneficial attributes of fungal pigments, such as antimicrobial, anticancer, antioxidant, and cytotoxic activity, have expanded their use in different sectors. This review deals with the study of fungal pigments and their applications and sheds light on future prospects and challenges in the field of fungal pigments. Furthermore, the possible application of fungal pigments in the textile industry is also addressed. [ABSTRACT FROM AUTHOR]