Natural Color Research Articles

Towards equitable reporting of Indigenous status, ethnicity, language and country of birth in Australian paediatric clinical studies: A scoping review.

This scoping review aims to expansively review the reporting of Indigenous status, ethnicity, culture, language and country of birth in Australian paediatric clinical studies. Scoping review of Australian clinical studies, including randomised controlled trials, non-randomised controlled trials, cluster randomised controlled trials and quasi-experimental studies, with paediatric participants (<18 years) or mixed adult and paediatric participants. PubMed, Cumulated Index to Nursing and Allied Health Literature and Embase databases were searched for clinical studies published 1 January 2018 to 28 November 2022. Of the 2717 studies identified in the search, 209 clinical studies were included. Overall, 131 (62.7%) clinical studies captured in this review did not report any of the variables of interest. When reported, terms used by study authors varied extensively and subsequently five study-defined categories emerged 'Indigenous status', 'race', 'race and ethnicity', 'ethnicity', or 'natural skin colour'. 'Indigenous status' was most reported (n = 37, 17.7%), followed by 'ethnicity and/or cultural background' (n = 15, 7.2%), 'race and ethnicity' (n = 4, 1.9%), race (n = 1, 0.5%) and 'natural skin colour' (n = 1, 0.5%). Furthermore, language used at home was reported in 27 studies (12.9%) and country of birth in 23 studies (11.0%). This review demonstrated very low reporting of Indigenous status, ethnicity, culture, language and country of birth in Australian paediatric clinical studies. Poor reporting has raised concerns surrounding generalisability of findings from these trials in addition to equity. The recent international shift encompassing improved clinical trial reporting requirements, for ethnicity and race, require prompt establishment in the Australian clinical trial domain.

Digitalisation Empowerment of Business to Digital Innovation in the Achievement of SDGs: A Survey on Creative Msme Actors in Indonesia

Objective: This study aims to test and analyse the relationship patterns of digital business-based training, empowerment of MSME actors, digital self-efficacy and digital innovation in creative MSMEs for the achievement of SDGs in MSMEs in West Java and Banten Provinces, Indonesia. Theoretical Framework: Digital literacy is needed so that a person has the ability to access information related to digital-based media. MSMEs are required to have renewable digital-based business methods in order to provide optimal and satisfying services. When MSMEs have high digital literacy through digital-based training, they could increase high self-efficacy. Empowering MSMEs based on digital business is very necessary in the digital era. Human resources in the organisation is expected to have digital competencies (skills, knowledge, attitude). Also, employees are expected to increase digital self-efficacy in order to increase digital innovation and MSME performance in the long term. Method: This study uses quantitative method by distributing questionnaires to 250 natural colour batik MSMEs in West Java and Banten Provinces. 207 questionnaires are filled in completely and then processed with Partial Least Square statistical techniques. Results and Discussion: This study finds that digital-based business training has a significant positive impact on the empowerment of MSME actors, and digital self-efficacy of MSME actors. In addition, empowerment of MSME players has significant positive impact on digital innovation and digital self-efficacy. On the other hand, digital self-efficacy of MSME actors has significant positive impact on digital innovation and is able to mediate the effect of business digital-based training on digital innovation. However, empowerment of MSME actors cannot mediate the effect of business digital-based training on digital innovation. Research Implications: This study provide guidance for the government and MSME empowerment organisations to design more targeted digital-based training. In addition, this study highlights the importance of supporting technological infrastructure and providing wider access to digital technology, especially for creative MSMEs in Indonesia. This study also enriches the literature on the role of digital training on digital empowerment and digital self-efficacy. Likewise, it provides implications for the role of digital empowerment and digital self-efficacy in encouraging digital innovation. Originality/Value: This study offers a business digitalisation empowerment model for creative MSMEs in order to increase digital innovation for creative MSMEs in achieving SDGs in Indonesia. The research model considers digital-based business training, empowerment of MSME players, and digital self-efficacy.

Berry pomace as a potential ingredient for plant‐based meat analogs

AbstractGiven the projected global population growth and the associated increase in demand for sustainable and nutritious food options, plant‐based meat analogs are increasingly popular. Berry pomace, a by‐product of the juice and wine industry, emerges as a promising ingredient for enhancing these products. This paper comprehensively explores the innovative use of berry pomace in the development of plant‐based meat analogs. It highlights key components such as antioxidants, natural colorants, dietary fibers, oils, and micronutrients, which significantly contribute to enhancing the nutritional profiles, sensory qualities, and shelf stability of these analogs. Methods for incorporating berry pomace into plant‐based meats, including direct addition and the addition of berry pomace extract using innovative technologies, such as high‐moisture extrusion, 3D printing and emulsion methods, are discussed. Moreover, the challenges of integrating berry pomace into plant‐based meats are critically analyzed, focusing on variability in pomace composition, potential sensory impact, and the technological adaptations required for optimal use in food production. The potential of berry pomace to enhance both the quality and appeal of plant‐based meats is highlighted, underscoring its significant contribution to the development of more sustainable food systems by valorizing food waste to high‐value products.

Dyeing behaviour of iron(III)-gallic acid complexes on wool as function of pH-dependent iron(III)-complex stoichiometry

Iron complexes with polyphenolics e.g. gallotannins and flavonoids have been used since ancient times for coloration of textiles, painting and preparation of inks. The composition of iron gall inks on historical artefacts has been investigated with modern instrumental methods. However the dyeing behaviour of iron-complexes with polyphenols still bases on empirical knowledge. In this study Fe(III)-complexes with gallic acid were used as model system to elucidate their pH dependent sorption and dyeing behaviour on wool. At dyebath pH 3 high sorption of Fe(III)-gallic acid complexes was observed, however darker dyeings were obtained at dyebath pH 4. Model calculations for the complex species present in the dyebath indicated the presence of the binary complex [Fe(III)(GA2−)]+ as main species at pH 3, while at pH 4 the ternary species [Fe(III)(GA2−)2]- prevails. The dye sorption bases on Van-der-Waals forces, while ionic interactions between Fe(III)-complex and keratin are of minor relevance. The elaborated theoretical model also explains the influence of dyebath pH in dyeing with gallotannins, polyphenols and flavonoids in presence of iron salts and thus is of particular relevance for improved utilisation of these natural colorants.

Colour-Coding Aegean Elites: Status and Cultural Identities in Linear B Dyed Textiles and Late Bronze Age Socio-Political Changes

Abstract This paper analyses the dyed textiles that are recorded in Linear B tablets and explores their role within the changes that the Late Bronze Age Aegean socio-cultural and economic scenario underwent. Additionally, it addresses how Aegean elites visually conveyed cultural messages on power and identities through colours and coloured textiles. As such, this paper (i) hypothesises new associations between red-dyed textiles, the chronology of Linear B tablets from Knossos, and the socio-political and cultural development of the Late Bronze Age; (ii) contributes new insights into the cultivation of plants producing red dyes throughout the period of the Knossos tablets use; (iii) challenges the interpretation of terms referring to the red natural colour of the wool; (iv) critically reviews the interpretation of terms referring to the grey natural colour of the wool; (v) hypothesises a new interpretation of how green-dyed textiles were obtained.

Effectiveness Evaluation of Silicone Oil Emulsion In Situ Polymerization for Dehydration of Waterlogged Wooden Artifacts

Organosilicon materials have shown potential as dehydration agents for waterlogged wooden artifacts. These materials can polymerize under normal conditions to form polymers with favorable mechanical strength, antibacterial properties, and aging resistance. However, the insolubility of most organosilicon hindered their penetration into waterlogged wood, which may lead to an unwanted cracking. This study aimed to evaluate the effectiveness of polydimethylsiloxane (PDMS) and hydroxy-terminated polydimethylsiloxane (PDMS-OH) with low viscosity and moderate reactivity for dehydrating waterlogged wooden artifacts from the Nanhai No.1 shipwreck. Four surfactants ((3–aminopropyl) triethoxysilane (APTES), alkyl polyoxyethylene ether (APEO), tri-methylstearylammonium chloride (STAC), and fatty alcohol polyoxyethylene ether (AEO)) and cosurfactant were employed to transform the two kinds of water-repellent silicone oils into eight groups of highly permeable oil-in-water (O/W) emulsions. Under the catalysis of a neutral catalyst, in situ polymerization occurred within the wood cells. Group P2-2 formulated with PDMS-OH and APEO showed the best efficiency in maintaining the dimensions of the wood during dehydration. The dehydrated wood exhibited a natural color and texture with a minimal volume shrinkage rate of 1.89%. The resulting polymer adhered uniformly to the cell walls, effectively reinforcing the wood cell structure. The weight percent gain of the wood was only 218%, and the pores of the cell lumen were well maintained for future retreatment. This method effectively controlled the sol–gel reaction process of the organosilicon and prevented damage to the wooden artifact during the dehydration process. Moreover, the dehydrated wood samples only experienced a low weight gain of 17% at 95% relative humidity (RH), indicating their great environmental stability.

Brazilin Content, Color Stability, and Antioxidant Activity of Sappan Wood (Caesalpinia Sappan L.) Traditional Drink by Different Blanching and Drying Methods

Caesalpinia sappan L (CS) heartwood is used as a natural red colorant in several Asian ethnic traditional drinks both as sole ingredient or mixed with other herbs. However, the pigment is unstable and easily degraded during storage which affects consumer acceptance. This research aimed to investigate the effect of different blanching and drying methods on the color stability, brazilin content, and antioxidant activity of CS heartwood drinks. Steam blanching, water blanching, sun drying and cabinet drying were examined in this study. The most common method applied in traditional production, without blanching and sun drying, was used as a control. The experimental design used was complete randomized design with triplicates. Data are presented as mean ± standard deviation and analyzed by SPSS statistics version 20. The results showed that blanching and drying methods affected the color intensity. For a pure CS heartwood herbal drink, the sample prepared with water blanching and cabinet drying (BCD) showed the highest red value, leading to a 48 % improvement compared to the control. This red value is in accordance with the brazilin content. Sample BCD showed the highest brazilin content, which was 376 % higher than that of the control. Similarly, the BCD sample had the highest antioxidant activity and total phenolic content, with IC50 values of 98.99 ppm and 213.12 mg GAE g–1, respectively. This result revealed that brazilin might act as an antioxidant. Similar to the pure CS drink, the highest quality of mixed herbal drink was obtained by BCD sample. The results suggest that the combination of water blanching and cabinet drying (BCD) was the best method to improves the quality of CS heartwood drink both in pure and mixed herbal drinks as a functional drink. HIGHLIGHTS Samples treated with blanching and drying had higher brazilin content of Sappan heartwood drink There is a correlation between brazilin content and color intensity as well as antioxidant activity Blanching and cabinet drying improved the color stability of Sappan heartwood drink Blanching and cabinet drying increased the total phenolic and flavonoid content of Sappan heartwood drink GRAPHICAL ABSTRACT

Impact of Illuminant Metamerism on Colour Fidelity in Graphic Reproduction of Artistic Images

The aim of the research was to to evaluate the quality of illuminant metamerism by using Colour rendering index through similar paintings and half-tone reproduction images within the graphic industry. Employing the methodology of visual perception and testing conducted by standard observers, the study scrutinises how different colour techniques of paintings respond to diverse light sources under standardised conditions. This investigation is pivotal for understanding the chromatic fidelity and consistency of paintings and their reproduction with half-tone colours, by measuring the grey balance field, for all images. To find the most suitable light source and to complete the colour quality, the Osram LED light at 3000 K, 4000 K, and 6500 K is used. The resulting index could be deceptive in cases of significant disparities. The American IES TM-30-18 colour rendering index (CRI) metric, quantifies illumination metamerism's ability to faithfully depict natural colours. At every stage (R1–R15), the average colour reproduction CRI must be more than 90.

Postharvest integration of prickly pear betalain-enriched gummies with different sugar substitutes for decoding diabetes type-II and skin resilience - in vitro and in silico study

Postharvest processing plays a crucial role in harnessing the benefits of prickly pear fruit by utilizing betalain as natural colorants to replace artificial colors in model food systems. Prickly pear betalain-enriched gummies were developed using various sugar substitutes, including table sugar, xylitol, stevia, and fructo-oligosaccharides (FOS). These gummies were analyzed for in vitro enzymatic inhibition, anti-inflammatory effects and molecular docking studies for decoding diabetes type-II and skin resilience. FTIR and HPLC confirmed the presence of betalain and isorhamnetin across all gummies. FOS and stevia incorporated gummies exhibited the highest polyphenolics and antioxidant activity. Betalain extract combined with stevia and FOS showed significant in vitro enzyme inhibition compared to other studied gummies. Specifically, FOS gummies showed the highest inhibition rates for α-amylase (23.58 %), α-glucosidase (24.12 %), tyrosinase (54.68 %), and collagenase (2.38 %). Additionally, all samples were non-toxic to RAW cell lines and exhibited anti-inflammatory effects. Molecular docking studies corroborated the in vitro results, and pharmacokinetics profiling confirmed the gummies' suitability for oral consumption and skin safety. The developed prickly pear betalain-enriched gummies, particularly those formulated with fructo-oligosaccharides and stevia, demonstrate significant potential as functional supplements for managing diabetes type-II and skin-related conditions.

Multidimensional Exploration of Wood Extractives: A Review of Compositional Analysis, Decay Resistance, Light Stability, and Staining Applications

Extractives, which naturally evolve as fundamental defense mechanisms in wood against environmental stresses, hold an essential place in the field of wood conservation science. Despite their low content in woody substrates, extractives are chemically complex and can be extracted accurately by solvents with different polarities, covering key components such as aliphatic, terpenoid, and phenolic compounds. The application of solvent extraction allows for the effective recovery of these extracts from forestry waste, thereby creating new opportunities for their reuse in wood modification and enhancing the economic value and potential applications of forestry waste. In the wood industry, extractives not only act as efficient preservatives and photo-stabilizers, significantly improving the decay resistance and photodegradation resistance of wood, but also serve as ideal dyes for fast-growing wood due to their abundant natural colors, which lend the product a distinct aesthetic appeal. The aim of this paper is to provide a comprehensive review of the origin and distribution characteristics of wood extractives and to examine the impact of solvent selection on extraction efficiency. At the same time, the mechanism of extractives in enhancing wood decay resistance and slowing down photodegradation is deeply analyzed. In addition, specific examples are presented to illustrate their wide utilization in the wood industry. This is intended to provide references for research and practice in related fields.

Impact of liner treatment on the translucency of CAD/CAM multi-colored lithium disilicate and multi-layered zirconia implant-supported crowns, and evaluation of fracture strength of ceramic crowns.

This study aimed to evaluate the optical properties of liner-treated CAD/CAM Multi-colored lithium disilicate (Amber Mill Direct; AMD) and multi-layered zirconia (Omega multi; OM) implant-supported crowns, as well as their effect on the fracture strength of Ti or Zr abutments to which they were applied. After sintering AMD and OM ceramic blocks, they were classified into three groups: untreated, liner-treated, and liner-treated with added color. Optical properties were evaluated by analyzing color differences using background materials to assess translucency and the masking ability of liner-treated ceramics. Subsequently, the fracture strength of implant-supported crowns applied to Ti or Zr abutments was measured, and statistical analysis was conducted using Weibull statistics. Untreated AMD exhibited the highest translucency. Liner treatment reduced translucency in both ceramics, while color-added liner treatment increased translucency. Liner-treated AMD showed greater color difference compared to OM, whereas color-added liner treatment reduced the color difference. Fracture strength was highest in Ti abutment-OM crowns (548.03 N) and lowest in Zr abutment-AMD crowns (283.58 N). Additionally, the Weibull coefficient was over twice as high in Ti abutment-AMD crowns (m = 17.500). Color liners can adjust the high translucency of lithium disilicate ceramics to block discoloration, providing natural tooth-like color and enabling the creation of esthetic restorations. Furthermore, lithium disilicate ceramic crowns applied to Ti abutments exhibited high Weibull coefficients and fracture strengths.

Integration of Local Wisdom of Natural Color Sasirangan in Project-based Learning with STEAM Approach to train Science Literacy

&lt;span lang="EN-US"&gt;Science learning should provide meaningful experiences for students to understand various scientific phenomena in life. Integrating local wisdom in learning can improve scientific literacy because the various concepts learned are witnessed directly by students in life. This research uses theoretical studies to describe the integration of local wisdom of natural color sasirangan in project-based learning with the STEAM approach to improve science literacy.&lt;/span&gt;&lt;span lang="EN-US"&gt; The STEAM approach is in the form of a) science in the form of the phenomenon of abundant dye water from the pot due to expansion; b) technology in the form of sasirangan fabric dyeing machines; c) engineering in the form of manipulation of the use of natural dyes and fixation; d) art in the form of making sasirangan cloth motifs; e) Mathematics in the form of temperature measurement using a thermometer and heat to increase the temperature of the dye liquid. The stage of making sasirangan cloth consists of making patterns, jalujur, sisit, dye, dedel, washing and ironing. The concept of temperature and heat found in the process of making natural color sasirangan includes; a) the concept of temperature when cooked water slowly becomes hot; b) the concept of expansion on the phenomenon of natural dye water spilling from the pot when cooked; c) the concept of heat is seen in water that has a large mass requires more heat to achieve a certain temperature increase; d) The concept of radiant heat transfer can be proven when the sasirangan cloth is dried in the sun&lt;/span&gt;

Elevating anthocyanin extraction from mangosteen pericarp: A comparative exploration of conventional and emerging non-thermal technology

Mangosteen pericarp (MP) is abundant in bioactive compounds but is often discarded as waste, leading to environmental pollution. This study compared the extraction of dried MP using maceration and high-pressure processing (HPP). HPP at 10 min (500 MPa/20 °C) resulted in the highest ACNs, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities. It also significantly reduced residual enzyme activities (REA) of polyphenol oxidase (PPO) and peroxidase (POD) by 33.90 % and 8.27 %, respectively. Fourier-transform infrared spectroscopy (FT-IR) analysis revealed a new wavelength at 2665.25 cm−1, and scanning electron microscopy (SEM) showed significant pore formation in MP cells, indicating cell damage. HPP-10 min enhanced the extraction of bioactive compounds, which significantly elevated the thermal stability of ACNs at 60 °C. This suggests that HPP is a promising method for extracting and preserving ACNs and other bioactive compounds from dried MP, with potential applications as natural colorants.

MpDLDH gene is crucial for regulating growth and pigment biosynthesis through acetyl-CoA modulation in Monascus purpureus

Monascus spp. are traditional medicinal and edible filamentous fungi in Asian countries. Monascus pigments (MPs) are the most well-known beneficial secondary metabolites produced by Monascus and used as natural food colorants with a long history. However, the understanding of the MPs biosynthesis remains limited due to their complexity and diversity, and the known MPs biosynthetic gene cluster (BGC) is also incomplete. In this study, we re-predicted the MPs BGC based on the genome sequence of Monascus purpureus and found seven new genes that may be involved in MPs biosynthesis. Among them, MpDLDH encodes a putative dihydrolipoamide dehydrogenase, which is the E3 subunit of pyruvate dehydrogenase (PDH) multiunit complex for catalyzing pyruvate to acetyl-CoA. MpDLDH knockout significantly decreased the acetyl-CoA content, and resulted in small pale colony, dramatically reduced biomass, few conidia, and absence of cleistothecia. MpDLDH deletion seriously repressed MPs biosynthesis, but did not change its composition. In addition to the increase of intracellular MPs production and acetyl-CoA in the late growth stage on solid medium, MpDLDH overexpression had no obvious effect on the phenotypes. Since acetyl-CoA is the crucial substrate for both MPs biosynthesis and tricarboxylic acid cycle, it is believed that MpDLDH of MPs BGC plays a key role in regulating cell growth, development and pigment formation through participating in the assembly of PDH complex to modulate the production of acetyl-CoA. These findings may deepen our understanding of the regulatory mechanisms between MPs biosynthesis and cell growth in Monascus species.

Eco-friendly and low-cost phytodyeing for wool, cotton and polyester textile materials using Parthenocissus Quinquefolia L. Fruit Extracts

This study investigates the extraction of natural colorant from fresh fruits of Parthenocissus quinquefolia L. and the application of the extracted dye to wool yarn, cotton, and polyester fabrics in the presence and absence of various mordants. The effect of mordant type on the dyeing quality with different mordanting methods was examined. Iron sulfate, tin chloride, alum, copper sulfate, and potassium dichromate were used as mordant. The effects of these mordants on the color of the dyed samples were investigated in terms of CIELab (L*, a*, b*) and K/S values. The light, washing and rubbing fastness of the dyed samples were evaluated according to ISO standards. While dyeing wool yarn without mordant produces reddish brown, and dyeing with mordant produces a wide range of colors from green to purple, blue and lilac tones are obtained in cotton fabric dyeing, and green, purple and brown tones are obtained in polyester fabric dyeing. While polyester fabrics are dyed with synthetic dyes at 130 oC, in this study they were dyed with natural dyes at 90 oC. As a result of dyeing, colors with high fastness are generally obtained.

Graphene oxide dispersed rose-petals based green chemistry synthesis of hybrid composite for novel spectroscopic applications

Rosa Santana family includes the rose, a highly prized decorative plant having symbolic, cultural, and commercial value. The exploration of graphene-based nanocomposites has expanded significantly, with recent research focusing on integrating these materials into natural and sustainable matrices. This study investigates the dispersion of graphene oxide (GO) within the biological structure of rose-petals, representing a novel approach to developing eco-friendly nanocomposites. The rich colours of the roses are ascribed to pigments such as flavanols, carotenoids, and anthocyanin. Carotenoids, which are found in natural colours including yellow, orange, violet, as well as another ingredient found in rose petals. By leveraging the inherent properties of rose petals, such as their unique properties and surface morphology and biocompatibility, this work highlights the potential of GO to enhance the mechanical, electrical, and optical characteristics of the composite. Advanced characterization techniques, including scanning electron microscopy (SEM), and electrochemical analysis, are employed to understand the interaction between GO and the rose petal substrate. The techniques of FT-IR, EDS, XRD, SEM, energy band gap, and CV were used in characterize the synthesis of doped graphene using rose petals extract. The findings underscore the synergistic effects of this natural-synthetic hybrid system, opening pathways to innovative applications in flexible electronics, biosensors, and sustainable material design. The novelty of this research lies in its foundational exploration of integrating graphene oxide with organic substrates like rose petals, offering a new direction for the development of environmentally benign graphene nanocomposites. Green chemistry based novel nanocomposite may open up new avenues for production of graphene oxide homogenious dispersion with rose-petal extract.

Eco‐friendly ultrasonic‐assisted appraisal of herbal‐based yellow natural colorant for silk dyeing

Eco‐friendly ultrasonic‐assisted <b>appraisal</b> of herbal‐based yellow natural colorant for silk dyeing

Biodegradable packaging with natural colorants added to increase the consumption of eco-friendly packaging

The development of biodegradable packaging is relevant for the environment, society, and industry. In parallel, using natural colorants has also emerged as a current topic in research, for its appeal to both human and environmental health. Combining the concepts of biodegradable packaging and natural colorants in a single product presents as a strategy to increase the potential use of biodegradable packaging. In this sense, this project starts with the following hypothesis: the offer of biodegradable packaging with a natural colorant added improves the positive perception of biodegradable packaging by the consumer. To this end, using the Food Choice Questionnaire (FCQ), the present work seeks to understand the effect of the construct natural content on the importance given by consumers to foods that are packaged in an environmentally friendly way, and using Word Association (WA) technique, to investigate the influence of color, and awareness of the presence of natural colorants on biodegradable packaging. The study was designed using two approaches: (i) Developing a model using Partial Least Squares-Path modeling (PLS-PM) to explain the whole set of relationships between FCQ constructs of interest in eco-friendly packaging, being mediated by the construct natural content; and (ii) using WA technique under two conditions: blind condition (unaware) and informed condition (aware) to explore the holistic perception of colored biodegradable packaging. Results showed that Ethical concerns and Health, had positive effects on Natural Content, while “weight control” had a positive effect on Natural Content. On the other hand, Mood was found to have a negative effect on Natural Content. Natural content has a high effect on the importance given by consumers to foods packaged in an environmentally friendly way. Word Association revealed a positive perception of the presentation of colored biodegradable packaging and a more positive perception, defined by happiness, of the awareness of its being biodegradable packaging colored by natural colorants. From a practical point of view, results showed that not only the use of natural colorants by the packaging industry can serve as an incentive to consume biodegradable packaging, but that consumers' awareness that the color is from a natural colorant can increase the consumption of eco-friendly packaging.

Improved yield of UV and heat-stable Monascus yellow pigment by statistical optimization of solid-state fermentation conditions and extraction process

Monascus species are well-known for their ability to produce biocolorants. A high-performing strain, M. purpureus F2–19, was recently developed by genome shuffling. Here, the entire bioprocess, starting from solid-state fermentation conditions to the extraction method, was statistically optimized to improve yellow pigment yield by the strain. Among culture conditions, monosodium glutamate concentration (used as nitrogen source), moisture content, and incubation period significantly influenced pigment production using less expensive broken rice as a substrate. Post-optimization, a yield of 1548.4 ± 14.6 AU/g was achieved, representing a 9.7-fold increase over the primary condition. The statistical model developed using central composite design of response surface methodology (CCD-RSM) is highly significant, with a P value of <0.0001. Similarly, a significant model (P < 0.0001) for extraction improved pigment yield further by 1.16-fold (actual output: 1796.4 ± 13.4 AU/g). The pigment remained highly stable with a preservation rate of ~90 % after 2.5 h exposure to a high temperature of 100 °C or UV light (254 nm). Even autoclaving at 121 °C for 15 min preserved 96.9 % of the pigment. These values are higher than reported for other commercial microbial yellow pigments, riboflavin, β-carotene, or lutein, thus highlighting its potential as a natural food colorant. Liquid chromatography-mass spectrometry (LC-MS) of the pigment identified nine distinct yellow compounds, with monascin being the most abundant. Thus, the optimized bioprocess would facilitate economical large-scale production of the yellow pigment; but its implementation still requires efficient selection of bioreactors and optimizations of scaling-up, especially the heat and mass transfer parameters.

Anthocyanin Extraction from Roselle (Hibiscus sabdariffa L.) Calyces: A Microwave-Assisted Approach Using Box-Behnken Design

Roselle (Hibiscus sabdariffa L.) is a widely consumed edible flower, often utilized as a natural coloring agent. The bright red color of roselle is due to its anthocyanin content. Beyond their role as colorants, anthocyanins are known for their potent antioxidant properties, which have drawn significant interest for their potential health benefits. To fully harness the advantages of roselle's anthocyanins, developing a reliable extraction method is crucial. This study aimed to establish a fast, efficient, and environmentally friendly extraction technique using microwave-assisted extraction (MAE). Key factors, such as temperature (30, 65, and 100 °C), solvent concentration (30%, 50%, and 70% ethanol in water), and solvent-to-solid ratio (10:1, 25:1, 40:1), were optimized using the Box-Behnken design combined with response surface methodology. The extraction time (5-30 minutes) was also evaluated to maximize anthocyanin recovery. Two major anthocyanins, delphinidin-3-sambubioside and cyanidin-3-sambubioside, were identified using UHPLC-PDA-QToF-MS and quantified using a cyanidin-3-glucoside calibration curve. The optimal extraction conditions were found to be 72 °C, using 70% ethanol in water with a 40:1 solvent-to-solid ratio for 15 minutes. This method was validated with high accuracy (>98% recovery) and precision (CV <6%). It was successfully applied to quantify the anthocyanin content in both purple and red roselle varieties. This rapid and effective MAE method offers a more sustainable, energy-efficient, and time-saving alternative to conventional extraction methods, benefiting industries that rely on natural colorants and antioxidants.