Red Rice Research Articles

Impact of lactic acid bacteria-mediated semi-solid fermentation on the nutritional, sensory, and gelatinization properties of colored brown rice varieties.

Novel umami peptides from Grass Carp marinated with Red Yeast Rice Flour and their taste presentation mechanisms characterized by in silico approach and sensory evaluation

Red yeast rice: From liver toxicity to liver transplantation

Plant-based fermentation offers a route to develop nondairy probiotic candidates, yet syrup-like matrices remain underexplored compared with solid or beverage systems. This study investigated fermented red rice syrup (prepared from red rice and barley malt powder) as a source of lactic acid bacteria (LAB) and advanced one isolate, SBM10. Cultivation on MRS supplemented with CaCO₃ yielded acidogenic colonies. A stable morphotype (SBM10) was purified and exhibited a LAB consistent profile, Gram-positive rods, catalase negative, TSIA K/A without H₂S, Simmons citrate negative, gelatinase negative, CO₂ positive in Durham and γ-hemolytic on 5% sheep blood agar. Under gastrointestinal stress models (4 h, 37 °C), tolerance relative to controls was 27.14% at pH 3.0 and 35.58% in 0.3% oxgall. In disk diffusion assays, the cell-free supernatant (CFS) showed no inhibition of Escherichia coli or Staphylococcus aureus. Thus, no antibacterial activity was detected by disk diffusion under the conditions tested, whereas amoxicillin produced zones of 13.95 mm and 12.43 mm, respectively. SBM10 presents a safety-supportive, LAB-typical profile with partial tolerance to gastric-like acidity and bile. Although no disk diffusion antagonism was detected for the CFS, the results motivate taxonomic confirmation and process/formulation optimization, such as improving acid/bile robustness and re-evaluating antimicrobial potential with complementary assays, to clarify the suitability of SBM10 for plant-based functional applications.

This study investigated changes in the physicochemical characteristics of starches obtained from unpolished red rice (URR) under germination and combined germination and heat–moisture treatment (HMT). Starches isolated from native, germinated, and germinated combined with HMT exhibited high purity, an A‐type crystalline structure, and irregular polyhedral granules measuring 3–8 μm in size. Germination did not influence the pasting temperature, trough and final viscosities, or setback of red rice starch. However, it increased the maximum viscosity, breakdown, and swelling power while reducing solubility. Germination elevated the concentration of rapidly digestible starch (RDS) and decreased the amount of resistant starch (RS). Notably, the increments in RDS and reductions in slowly digestible starch (SDS) and RS were positively correlated with longer germination durations (6–24 h). When HMT was applied after germination, increases were observed in pasting temperature, solubility, and RS content, while decreases occurred in maximum viscosity, breakdown, swelling power, and RDS content. Consequently, starches extracted from red rice germinated for 6 h and subsequently modified by HMT exhibited desirable characteristics, including the lowest RDS content (54.09%) and the highest RS content (30.39%) among all tested samples. These starches could be utilized in the production of low‐carb products.

Monascus purpureus, also known as red yeast rice, is a red mold widely used in traditional Asian food fermentation, particularly in Indonesia and China. One of its main bioactive compounds is monacolin K, a substance structurally identical to lovastatin, a well-known cholesterol-lowering statin drug. Monacolin K works by inhibiting the HMG-CoA reductase enzyme, a key enzyme in the biosynthesis of cholesterol in the liver. Various modern studies have demonstrated that Monascus purpureus consumption can significantly reduce total cholesterol, low-density lipoprotein (LDL), and triglyceride levels, while increasing high-density lipoprotein (HDL) levels, with relatively minimal side effects compared to synthetic statins. In addition, the natural pigments produced by Monascus purpureus, such as monascin and ankaflavin, exhibit strong antioxidant and anti-inflammatory activities that help protect vascular endothelial cells from oxidative stress and inflammation—two major factors contributing to atherosclerosis. The combination of M. purpureus extracts with probiotics or other natural ingredients, such as garlic or fermented soy products, has also been shown to produce synergistic effects in improving lipid metabolism and promoting cardiovascular health. With its potent bioactive components and high safety profile, Monascus purpureus holds great potential to be developed as a natural anticholesterol agent for the prevention and management of dyslipidemia in a sustainable and effective manner.

Aims: Submergence a major abiotic factor especially in paddy growing lowland areas, as these regions are prone to flood and submerged conditions. Considering, this as a major factor, the variety Sahyadri Kempumukthi, a National check for red rice, is the popular variety in hilly and transitional zones of Karnataka replacing Jyothi, cultivated on 1.20 L ha of land. It is susceptible to submergence stress. With this background, to make it tolerant, backcross breeding programme was carried out to transfer SUB 1 gene from Swarna Sub 1. Study Design: Randomized Complete Block Design. Place and Duration of Study: Department of Genetics of Plant Breeding, ZAHRS Shivamogga, Karnataka, India, Kharif 2024, July 2024 and July 2025. Methodology: The study was carried out to screen, 40 backcross derived lines (BC1F3) of cross Sahyadri Kempumukthi × Swarna Sub-1, along with four checks for fourteen yield attributing traits under the design RCBD. Top performing 20 lines based on yield performance were evaluated for 14 traits. Results: The analysis of variance showed significant variation among 14 rice attributes, as seen by the standardised range and coefficient of variation. Correlation study revealed the highest significant positive association of the test weight, spikelet fertility, number of productive tillers with grain yield indicating the effectiveness of indirect selection for these traits in improvement of grain yield per plant. Twenty promising lines were found to be better performing than parents with range of 60 to 87 q/ha.The Backcross lines K×S-6-2-1 and K×S-11-4-2, showed superior grain yield of 85.38 and 86.45 q/ha, respectively. While K×S -6-2-1 and K×S-12-4-1 were better performing for yield. Conclusion: Therefore, making these lines precious for selection. These lines are needed to be forwarded to further generations and evaluated under diverse environments to conduct MLTs, and may be proposed for further varietal release programmes.Practical implications by providing good nutritional benefits, along with good yield to farmers in turn adding to their income.

Sprouts from various rice varieties have a significant impact on prospective health benefits, particularly in the management of hypertension. Rice sprouts include bioactive substances such as antioxidants, flavonoids, and phenolics, which have a nutritional influence and increase the bioavailability of minerals (sodium, magnesium) and can help reduce oxidative stress and lower blood pressure. Incorporating these sprouts into dishes may aid in the prevention and management of hypertension through natural dietary approaches. The goal of this study was to determine the chemistry, concentration of bioactive chemicals, antioxidant activity, and potential health advantages of noodles made from organic colored rice sprouts for lipid profiles, blood pressure, and oxidative stress markers. Three distinct types of noodles were prepared for the study utilizing a composite flour derived from tapioca flour, green bean sprout flour, brown rice sprout flour, brown rice, or a specific type of black rice. The chemical composition was determined using dietary fiber, resistant starch, and proximate analysis. Flavonoids and phenolic compounds were among the bioactive chemicals analyzed. The antioxidant activity was assessed using the DPPH method. Triglycerides, cholesterol, low-density lipoprotein (LDL), and highdensity lipoprotein (HDL), as well as blood pressure and oxidative stress markers (TNF-α and IL-6), are also assessed. Based on organic colored rice sprouts, the research findings showed that noodles outperform commercial noodles in terms of fiber content, resistant starch, bioactive components (phenols and flavonoids), and antioxidant activity. Consuming organic colored rice noodles can increase HDL levels while decreasing LDL and total cholesterol. Experimental rats fed organic colored rice sprout noodles had lower systolic blood pressure and oxidative stress markers (TNF-α and IL-6). Black rice noodles outperform red and brown rice noodles in lowering blood pressure, reducing oxidative stress, and improving lipid profiles. According to the study's findings, an organic red rice noodles formulation rich in dietary fiber, resistant starch, and antioxidants might be developed as a functional food.

Evidence - Based Claim Substantiation for Red Yeast Rice (RYR) : A Narrative Review

Green technology for glycemic control: developing rice starch-red rice bran polyphenol complexes through ultrasonication and freeze-thaw treatment.

Many researchers have shown that red rice bran is a rich source of antioxidants and has potential anticancer properties. This research aims to evaluate the cytotoxicity and inhibitory effects of Red Rice Bran Extract (RRBE) on the growth and migration of human cervical and breast cancer cells. HeLa and MCF-7 cancer cells were treated with various concentrations of RRBE for 24 and 48 h. Cytotoxicity was assessed using the MTT assay. Then, the half-inhibitory concentration (IC50) value was determined. The anti-proliferative effects were evaluated using the MTS assay, and the anti-cell migration activity was assessed using the wound healing assay. It was found that the RRBE exhibited cytotoxicity to both HeLa and MCF-7 cancer cells. As the concentration level increased (100 - 1000 µg/ml), the survival rate of the cells significantly decreased, especially at 48 h, corresponding to the IC50 values of 818.67 µg/ml and >1000 µg/ml for HeLa and MCF-7, respectively. Then, concentrations of RRBE with lower cytotoxic effects were selected for further experiments, which revealed that treatment with RRBE at concentrations of 100, 250, 500, and 1000 µg/ml significantly suppressed the proliferation and reduced the migration of those cancer cells. These results demonstrate that RRBE has potent anti-cancer activity in HeLa and MCF-7 cancer cells, making it a suitable candidate for in vivo studies and development as an anti-cancer agent.

The aim of this research was to investigate the total phenolic content and phytochemical constituents of broken landrace rice flour from the Hom Dok Hang group, Ban Khok Sa-At, Sakon Nakhon province. Four types of rice—Red Jasmine, Black Jasmine, Kam Noi, and Hom Phu Keaw—were studied. The rice samples were crushed and sifted into two grain sizes: large grains, greater than 250 µm, and small grains, less than 250 µm. The rice samples were then extracted using ethanol as the solvent. The total phenolic content was determined, and the highest quantity of total phenolic content was found in the small grains of Red Jasmine flour, measured at 69.37 ± 2.22 mg GAE g⁻¹ crude extract. For all rice types, the small grain size was found to have a higher phenolic content compared to the large grain size. The phytochemical was evaluated by qualitative analysis. It was found to contain anthraquinone, saponin, cardiac glycosides, terpenoids, flavonoids, coumarins, alkaloids, and tannins: however, steroids were not detected. Red Jasmine rice was selected as the main ingredient for product development. Kale powder and roasted black sesame powder were added to create a rice-based product targeted at menopausal women. The sensory properties of the product were evaluated, and the highest score was achieved with a recipe containing 85 g of Red Jasmine rice flour, 5 g of kale powder, and 15 g of black sesame powder. This study suggests that broken landrace rice flours are promising ingredients for food products, as they contain high levels of phytochemicals and antioxidants beneficial for health. Additionally, this approach adds value to raw materials that would otherwise be considered waste, such as broken rice, by transforming them into prototype food products. GRAPHICAL ABSTRACT HIGHLIGHTS This research provides a guideline for adding value to low-priced broken rice by transforming it into an instant rice product. This study found that rice ground into a finer size contains higher levels of important compounds, such as phenolic compounds and many phytochemicals, compared to coarsely ground rice.

This study investigated the extraction, solubility profile, phytochemical content, and proteomic profile of rice bran protein (RBP) from white (WRB), red (RRB), and black rice bran (BRB) using a modified three-phase partitioning (TPP) method. Protein solubility peaked at: BRB pH 3.4 (5.40 mg/mL), WRB pH 3.5 (5.10 mg/mL), RRB pH 3.6 (5.03 mg/mL). These differences may be attributed to pigment-protein interactions and inherent protein composition. Phytochemical analysis at optimum solubility pH determined common and specific metabolites of RBP types. Bioactive compounds such as isoflavones, trehalose, and amino acids were found in all samples. At the same time, colored rice brans exhibited a wider profile of secondary metabolites such as phenolics, alkaloids, and steroidal glycosides. Proteomic profiling identified universal seed storage proteins, antioxidant enzymes, and stress proteins across all RBP types. Variety-specific redox regulation and metabolism proteins were also observed, suggesting functional diversity. Integrating solubility optimization with protein and metabolite characterization provides a comprehensive understanding of RBP composition, indicating its potential value as a plant protein source and functional food ingredient. This study highlights solubility optimization, protein and metabolite characterization, and the nutritional potential of RBP as a sustainable plant source for food applications.

Colorectal cancer prevention is closely linked to gut microbiota modulation, particularly by increasing lactic acid bacteria (LAB) and short-chain fatty acids (SCFA). This study investigates the effect of fermented red rice bran on colon microbiota improvement. Fermented bran was produced by mixing red rice bran with water and yeast, followed by an analysis of the proximate composition, dietary fiber, resistant starch, antioxidants, and phenols. A quasi-experimental study was conducted on 30 mice, assigned to normal, negative control, 10% bran, 20% bran, 10% fermented bran, and 20% fermented bran groups. Colorectal cancer was induced using DMBA (20 mg/kgBW) intraperitoneally four times over two weeks. Treatment groups received bran or fermented bran ad libitum for 14 days. Cecal analysis showed that 20% red rice bran and 10% fermented bran significantly increased SCFA levels (p < 0.05), suggesting improved microbiota function, but did not significantly alter pH or LAB counts. These findings highlight the potential of fermented red rice bran in modulating gut microbiota, though further studies are needed to elucidate its long-term effects and mechanisms in colorectal cancer prevention.

Acute kidney injury (AKI) caused by red yeast rice Cholestehelp® (CP) tablets has become a public health issue in Japan. Puberulic acid (PA) contaminated in CP tablets may cause AKI; however, we detected silica nanoparticles in a CP patient. CP-related kidney injury was examined in rats that underwent left nephrectomy to increase silica nanoparticle loading. Six male Sprague-Dawley rats were administered CP and underwent left nephrectomy on day 4. Blood and urine samples were collected on day 11. Renal tissues were observed by electron microscopy and low-vacuum scanning electron microscopy-energy dispersive X-ray spectroscopy (LVSEM-EDS). The amount of PA in CP was measured, and PA was administered to normal rats and unilaterally nephrectomized rats. Normal rats receiving CP (2KCP) had increased urine volume and lower urine specific gravity than controls, but no significant changes were observed in urinary protein, renal function, electrolytes, or blood gasses. Unilaterally nephrectomized rats receiving CP (1KCP) had increased water intake and urine volume, decreased urine specific gravity, and increased low-molecular-weight proteinuria. The glomeruli of 1KCP rats showed expanded subendothelial space and increased endocytic vesicles were observed in the proximal tubules relative to 2KCP rats. The accumulation of nanoparticles in the endosomes of the proximal tubules, and LVSEM-EDS detected silicon in renal tissue. Administration of PA at the doses in CP tablet did not result in significant renal injury. Uninephrectomized rats administered CP tablets showed accumulation of silicon-containing nanoparticles in the proximal tubules and renal injury.

ABSTRACTWith heart disease being the leading cause of death worldwide, cost‐effective therapies supporting healthy cardiac function are highly needed. Oxidative stress and hypercholesterolemia are risk factors in the pathogenesis of cardiac dysfunction. Many nutraceutical compositions containing Coenzyme Q10, resveratrol, extracts of Ginkgo biloba leaf, Garlic Bulb, red rice yeast, and bovine colostrum appear to have the potential to improve cardiac function. In the present study, we aimed to evaluate whether a new combination containing the abovementioned nutraceuticals (Cardio) is protective against damage to cardiac function. In this study, C57BL/6J mice were divided into groups of control, high‐fat‐cholesterol diet fed (HFHC), and HFHC diet + Cardio (Cardio group), and fed for 16 weeks. Parameters of plasma lipid levels, inflammation, oxidative damage, and cardiac function were measured. Cardio treatment significantly inhibited hypercholesterolemia, reduced levels of cardiac damage markers including LDH and CK, improved cardiac function, and reduced HFHC diet‐induced increased levels of inflammatory cytokines including TNF‐α and IL‐1β. Our data showed that Cardio has a protective effect on cardiac dysfunction probably by ameliorating hypercholesterolemia, inflammation, and oxidative stress.

Iron (Fe) and zinc (Zn) deficiencies, globally prevalent nutritional disorders, underscore the need for effective fortification strategies in staple foods like rice. This study evaluates a bioprocess-based technique for single (SF) and double fortification (DF) of two heritage red rice genotypes (Chennangi—CH, Karungkuruvai—KK) to enhance mineral content and bioavailability. Whole rice grains were germinated in sodium iron EDTA and zinc chloride solutions (SF: 50 and 100 mg/L Fe/Zn; DF: Fe + Zn at a 2:1 ratio). Mineral quantification via microwave plasma atomic emission spectrometry (MPAES) revealed that SF significantly increased fortified mineral content but reduced accessibility of the non-fortified mineral. In contrast, DF substantially enhanced both Fe (2-fold) and Zn (7-fold) content while improving bioaccessibility (Fe: 2–2.5x; Zn: 3–7x), supported by reduced phytate levels. Both genotypes exhibited high Zn accumulation and retention. Cooked DF rice has good sensory acceptability and improved cooking characteristics. At daily consumption levels of 30–150 g, DF rice could meet 16–70% of Fe and nearly 100% Zn Recommended Dietary Intake (RDI) across age groups. This simple, scalable bioprocessing method effectively enhances Fe and Zn bioavailability in wholegrains, offering a promising solution to combat micronutrient deficiencies through dietary staples, contributing to Sustainable Development Goals (SDG 2 and 3) by promoting accessible nutrition for healthier populations.

Snack bars are practical rod-shaped food products generally made from a mixture of nutritious ingredients and consumed as a source of energy and nutrients. The purpose of this study was to determine the optimal treatment combination of flaxseed flour and brown rice flour, supplemented with honey, to produce snack bars with the most beneficial nutritional properties. This study employed a Completely Randomised Design (CRD) with a factorial pattern, involving two factors and three replications. Factor I: flaxseed flour: brown rice flour (20%: 80%; 25%: 35%; 30%: 70%) and factor II: the addition of honey (40%; 45%; 50%). The Data were analysed using ANOVA and Duncan’s Multiple Range Test (DMRT) to determine if there were significant differences at a 5% level, while the organoleptic data were analysed using the Friedman Test at a 5% level. Treatment of flaxseed flour proportions : brown rice flour (30%; 70%) and the addition of honey (40%) is the best treatment that produces a snack bar with the characteristics of water content 12.38%, ash content 2.35%, protein content 11.78%, fat content 8.78%, crude fiber content 5.95%, carbohydrate content 64.57%, total calories 386 (kcal/100 grams), hardness texture 6.388 (N), chewiness texture 189.891, and taste organoleptic test 4.80 (neutral), color 5.00 (like), aroma 4.90 (neutral), texture 4.73 (neutral). Contribution to Sustainable Development Goals (SDGs):SDG 2: Zero HungerSDG 3: Good Health and Well-Being

The health hazards, including kidney damage, were reported following the ingestion of a health food product, so-called "foods with functional claims (FFC)'', containing beni-koji (red yeast rice), a product of Monascus pilosus very recently in Japan. Puberulic acid (PA) was detected as an unexpected compound in FFC products, and further investigation was required to identify additional unintended compounds and determine the route of PA contamination. To date, we have reported the possibility contamination of FFC products by Penicillium adametzioides in a manufacturing facility, and the presence of two novel unintended compounds, designated as compounds 1 and 2. However, the mechanism underlying the formation of compounds 1 and 2 in FFC products remains unclear. To investigate this mechanism, culture extracts of M. pilosus, P. adametzioides, and their co-cultures were analyzed. Two unintended metabolites were detected in the co-culture samples of M. pilosus and P. adametzioides.

The study aimed to analyze the starch extracted from red and white rice physico-chemically and structurally. The alkaline steeping procedure was utilized to extract the starch. Alkaline extraction is the most effective method for extraction of starch from rice, yielding an impressive 70% of the total starch. The extraction yield was found to be 58% and 65%, in white rice and red rice, respectively. The results revealed red rice contained moisture 11.80%, ash 0.50%, crude fat 0.51%, crude protein 0.32%, water absorption 109 g/100g-1, oil absorption 76.60 g/100g-1, starch 82.50% and amylose 25.71 % whereas in white rice moisture was 11.20%, ash 0.25%, crude fat 0.34%, crude protein 0.46%, water absorption 81 g/100g-1, oil absorption 56.60 g/100g-1, starch 86.33% and amylose 17.23%. The peak of crystallinity degree obtained in XRD of red rice was 19 ɵ and white rice was 20 ɵ, respectively. The FTIR results revealed the peak of maximum intensity spectral bands at red rice 1012.77cm-1 and 998.62cm-1 of white rice. This study compares the physicochemical properties of red and white rice starches using FTIR, XRD, proximate composition, amylose content, starch yield, and water/oil absorption capacities. Despite challenges like compositional variability and limited red rice data, we identified distinct differences in amylose content and crystallinity, influencing functional properties. Red rice starch showed higher yield and unique molecular traits, suggesting suitability for health-focused products. These findings bridge knowledge gaps, support rice breeding, and promote red rice for sustainable food applications.