Total Carotenoids Research Articles

Impact of inorganic mercury on carotenoids in freshwater algae: Insights from single-cell resonance Raman spectroscopy

The influence of inorganic mercury (Hg(II)) exposure on photosynthetic microorganisms and their pigments remains understudied. Here, we employed resonance Raman (RR) spectroscopy to investigate the responses of two freshwater phytoplankton species, the green alga Chlamydomonas reinhardtii and the diatom Cyclotella meneghiniana to Hg(II) exposure. We selectively recorded the spectral RR signature of carotenoids in intact cells exposed to concentrations of 10 nM and 100 nM of Hg(II), representative for contaminated environment and unexposed control cells. A two-hour exposure of C. reinhardtii resulted in a slight decrease in lutein and β-carotene levels, while total carotenoids RR band broadening, as revealed by the FWHM of the υ1(C=C) stretching mode from averaged RR spectra, suggested conformational changes in pigments. Higher Hg(II) concentration induced more pronounced conformational changes. Similarly, a two-hour exposure of C. meneghiniana resulted in slight decreased level of the fucoxanthin, while diadinoxanthin showed an opposite trend compared to control: when fucoxanthin decreased, diadinoxanthin increased under 10 nM Hg (II) exposure. At higher concentrations, the decrease in fucoxanthin was less pronounced, accompanied by a broadening of the band area, (with FHHM increased), indicating possible conformer occurrence in response to Hg-induced stress. The changes in the main carotenoid species of the two algae are species-specific, Hg(II) concentration-specific, and dependent on exposure time. The calculated spectral differences in absorbances from UV–VIS spectra of methanol extracts from each group supported the main findings obtained by RR, though with caution due to the selective extraction efficiency of the respective carotenoids. This study highlighted for a first time the capability of single-cell RR spectroscopy as a valuable tool for toxicity assessment and for comprehending early-stage alterations in carotenoid metabolism due to toxic metal exposure in vivo.

Packaging and storage of Porphyridium cruentum: Metallised polyethylene terephthalate/polyethylene (PETmet/PE) versus polyethylene (PE)

AbstractThe effect of the storage conditions of light (presence; absence) and relative humidity (50%; 75% RH) on the water content and colour of Porphyridium cruentum microalga powder was studied, then two packaging materials, low-density polyethylene (PE-LD) and metallised polyethylene terephthalate with polyethylene (PETmet/PE), were used to study their effect on the water content, colour, total carotenoids and chlorophylls contents, total phenolic content (TPC), and antioxidant activity (ABTS, DPPH, ORAC) of P. cruentum during storage at 23 °C and 50% RH. An atmosphere with 50% RH is recommended to minimise the water vapour absorption and lightness loss. In addition to the expected light protection, PETmet/PE material protected P. cruentum powder also against water absorption, contrary to PE material. There were no relevant colour changes of the microalga during storage in PETmet/PE. Regarding the total content of carotenoids and the antioxidant activity of the microalga, no significant differences were found between the biomasses stored in either packaging material. The TPC and DPPH values were practically constant during two months of storage, while ABTS and ORAC decreased more than 50% and 20%, respectively, during this time.

ORANGE gene positively regulates chromoplast formation and carotenoid accumulation in Osmanthus fragrans

Sweet osmanthus (Osmanthus fragrans) cultivar from Aurantiacus Group shows orange or orange-red flower color due to the accumulation of abundant carotenoids in the petals. Orange (Or) gene has been functionally characterized in the formation of plant chromoplasts and carotenoid accumulation in several species. However, whether Or gene from sweet osmanthus plays essential role in the formation of plant chromoplasts is not clear. In this study, we isolated Or homologous gene OfOr from sweet osmanthus by transcriptome homology search. The protein encoded by the gene has two transmembrane domains and a zinc finger domain, and is co-localized with the chloroplasts. Transmission electron microscopy analysis of the petal tissues of sweet osmanthus showed that the chromoplast volume, the plastoglobule number and volume increased significantly with petal development, accompanied by an increase in the expression level of OfOr. Correlation analysis showed that the development of chromoplasts was significantly positively correlated with the expression pattern of OfOr. In addition, after stable overexpression of OfOr in tomato (Solanum lycopersicum), it was found that the transgenic tomato fruits exhibited significantly higher redness, yellowness and chroma, as well as an increased distribution of carotenoids in the pulp cells, with total carotenoid content significantly higher than that of wild type. In summary, our study indicate that OfOr positively regulates chromoplast formation and carotenoid accumulation. This study also further reveals that OfOr can be used as a novel genetic tool to increase the accumulation of carotenoids and improve the coloring of colored organs in crops and ornamental plants.

The Effect of Acrylonitrile Butadiene Styrene (ABS) and Polypropylene (PP) Microplastics on Ulva lactuca L. and Ceramium diaphanum R. Algal Growth

The goal of this study was to determine the effects of acrylonitrile butadiene styrene and polypropylene microplastics as two typical classes for microplastic pollution on algal growth, lipids, carbohydrates, chlorophyll-a and total carotenoid content of Ulva lactuca L. and Ceramium diaphanum R. collected from the Gulf coast of Izmir province. The results demonstrate that ABS-MPs had no statistical effect (P>0.05) on the various physiological parameters of U. lactuca macroalgae after 5 days of exposure, except for the total carbohydrate and lipid concentration. The chl-a value of C. diaphanum was considerably increased under the low concentration of ABS (25 mg L-1), increasing by 81.56% compared with the control while the amount of chl-a decreases (32.05%) in parallel with the increasing concentration of PP-MPs. Laboratory incubation experiments showed that MPs affect relative growth rate, pigments efficiency or carbohydrate content of C. diaphanum until reaching an extremely high concentration (100 mg L-1), indicating a high tolerance to MPs. The results showed that two macroalgae species, especially U. lactuca, were not highly affected at low MPs concentrations under laboratory conditions which were much higher than the levels of environmentally relevant concentrations.

Preharvest applications of monopotassium phosphate to improve fruit quality and volatilome composition in cold-stored cherry tomatoes

The experiment addressed the effects of preharvest KH2PO4 foliar spraying (20 mmol · L−1) on fruit quality and composition (including volatile organic compounds, VOCs) of cherry tomatoes (‘Caravaggio’, ‘Sugarland’ and ‘Top Stellina’) after 0 (S0), 7 (S7) and 14 days (S14) of storage at 8.0 °C. On the average of the 3 genotypes, the KH2PO4 treatment improved fruit pressure firmness, total soluble solids (TSS), titratable acidity (TA), total phenols and carotenoids concentrations, along with the fruits' antioxidant capacity (by up to 17% for FRAP assay). Within the S7–S14 period, control fruits showed the highest reductions in TSS, TSS/TA ratio and total carotenoids (−17, −12 and −45, respectively), whereas treated fruits proved the strongest increase in DPPH (+12%). Sixteen out of 32 VOCs were promoted following KH2PO4 application, including the aldehydes hexanal, (E)-2-hexenal and (Z)-3-hexenal and the apocarotenoids (E)-citral, (E)-β-ionone, geranylacetone and 6-methyl-5-hepten-2-one. Proceeding from S0 to S14, several VOCs decreased more strongly in control fruits, as for hexanal (−48%∖) and total aldehydes (−42%∖, whereas at S14 treated fruits had higher concentrations of linalool, geranylacetone and 6-methyl-5-hepten-2-one (1.06, 52.50 and 79.27 μg · kg−1, respectively). ‘Caravaggio’ demonstrated the strongest apocarotenoid reduction at S14, whereas ‘Top Stellina’ was more responsive to KH2PO4 (mainly for β-cyclocitral, geranylacetone and total terpenes/terpenoids), thus highlighting the central role of the genotype in responding to other experimental factors. Nonetheless, these results suggest that proper preharvest KH2PO4 applications can preserve specific commercial, nutritional and quality traits of cold-stored cherry tomatoes.

Ecotoxicological effects of triclosan on Lemna minor: bioconcentration, growth inhibition and oxidative stress.

Triclosan (TCS), an emerging pollutant, is a notable contributor to adverse impacts on aquatic organisms due to its widespread use during COVID-19 and hydrophobic properties. There is extensive documented literature on TCS toxicity in commercially important fish species; however, studies on aquatic plants remain limited. In this prelude, the present study aims to evaluate the effect of TCS on Lemna minor, a commercially important aquatic plant species for 7days. The results showed dose-dependent significant alterations in growth, pigments and stress enzymes of L. minor at varied concentrations of TCS (1 to 8mg L-1). Median inhibitory concentration (IC50) was found to be 4.813mg L-1. Total chlorophyll and carotenoid levels decreased 73.11 and 81.83%, respectively after 7days of TCS exposure. A significant increase in catalase and superoxide dismutase activity was observed in TCS exposed groups as compared to the control. Bioconcentration factor was found to be in the range of 5.855 to 37.129 signifying TCS ability to accumulate and transfer through the food chain. Scanning electron microscopy (SEM) analysis showed deformation in the cell surface and alteration of stroma morphology of TCS exposed groups. Furthermore, the Fourier transform infrared spectroscopy (FTIR) study also revealed that higher concentrations of TCS could cause alteration in the functional groups in the plant. This study demonstrates that TCS negatively impacts the growth and metabolism of primary producers, offering crucial insights into its interactions with aquatic plants and establishing baseline information essential for crafting effective mitigation strategies for TCS contamination in aquatic environments.

Biodegradable active films based on Chlorella biomass and cellulose nanocrystals isolated from hemp stalk fibers

Cellulose nanocrystals (CNC)-reinforced biopolymers have emerged as a widely embraced approach for enhancing the characteristics of biopolymers due to their exceptional properties. Biocomposite (Chl-CNC) films were fabricated by blending Chlorella biomass and varying concentrations of CNCs via a solution casting technique. CNCs were effectively isolated from hemp stalk fibers, as confirmed by structural, surface, thermal, and morphological analysis. The crystallinity of films increased by CNC incorporation, which was confirmed by the XRD. The presence of molecular interactions between CNC and protein-rich Chlorella biomass was illustrated with the FTIR analysis. These interactions enhanced the physicochemical properties of the films. Further, films demonstrated a high level of soil biodegradation in the 42 days, while their total phenolic, chlorophyll, carotenoid contents, and antibacterial activity were unaffected by the incorporation of CNCs. The Chl-CNC films, regardless of CNC addition, indicated antimicrobial activity toward Escherichia coli but not Staphylococcus aureus. These results indicate that developed biobased and biodegradable Chl-CNC films could be highly beneficial in active food packaging applications.

Effect of drying on bioactive compounds in Eugenia uniflora fruit pulp

AbstractEugenia uniflora is a tropical species rich in bioactive compounds that are highly sensitive to processing conditions, particularly those involving heat. Drying is a widely used method for preserving fruit pulp which can affect the stability of these bioactive compounds. The aim of this study was to assess the impact of drying at different temperatures on the retention of phenolic compounds and carotenoids present in the pulp of E. uniflora, with the goal of optimizing the drying process to preserve the pulp's quality. The E. uniflora pulp was dried in an oven with air circulation at three temperatures (45, 65, and 85°C). During the drying process, the moisture content and concentration of phenolics, β‐carotene, and lycopene were measured over time. After 260 min of drying, phenolic compounds decreased by 63.97% (45 and 65°C) and by 59.62% (85°C). Carotenoids losses were even more pronounced exceeding 89%, for all temperatures, with β‐carotene reductions of 92.91%, 90.72%, and 91.11%, at 45, 65, and 85°C, respectively. Several well‐established drying models were tested to represent the moisture content over time. Two models exhibited a high adherence to the experimental data. Zero‐order, first‐order, and second‐order degradation models were used to describe the concentrations of phenolic compounds and carotenoids. For total carotenoids, the model that showed the best results was temperature‐dependent. The first‐order model provided the best fit for β‐carotene and lycopene, with high R2 values of 0.9852 (45°C), 0.9776 (65°C), and 0.9681(85°C) for β‐carotene, and 0.9776 (45°C), 0.9715 (65°C), and 0.9659 (85°C) for lycopene. These results indicate that higher temperatures accelerate the degradation of bioactive compounds, following a predictable dynamic that can be optimized through adjustments to the drying process.Practical applicationsThe fruit of Eugenia uniflora contains phenolic and carotenoid compounds with significant nutraceutical potential. However, the production of this fruit is seasonal, necessitating effective preservation methods. Drying, which involves the removal of water from the pulp, is a common procedure aimed at extending the fruit's conservation and shelf life. Despite its benefits, the drying process poses a challenge, as bioactive compounds like phenolic and carotenoids are sensitive to thermal processing. Their degradation during drying can lead to a reduction in the fruit's bioactive potential. Therefore, it is crucial to understand the kinetics of drying and the degradation of these bioactive compounds to optimize the drying process and maximize the fruit's nutraceutical value.

Skin Carotenoids Are Related to Cognitive Abilities among Toddlers

BackgroundCarotenoids are antioxidant pigments that deposit in human tissues (e.g., skin, macula, and brain) upon dietary consumption. The health implications of skin carotenoids, which reflect overall dietary carotenoid consumption, have not been adequately studied in younger populations. ObjectivesThis work aimed to examine links between skin carotenoids and cognitive, language, and motor skills among toddlers. A secondary aim explored relationships between skin carotenoids and neurophysiologic outcomes of sensory memory [i.e., mismatch negativity (MMN)] and the functional integrity of the visual pathway [i.e., visual evoked potentials (VEPs)]. MethodsToddlers aged 12–18 mo (n = 45) were included in a cross-sectional study. Skin carotenoids were measured with reflection spectroscopy via the Veggie Meter®. Cognitive, language, and motor skills were measured using the Bayley Scale of Infant and Toddler Development IV Screening Test (BSID-IV). MMN and VEPs were collected with an auditory oddball task and a pattern reversal task, respectively, using electroencephalography. Analyses adjusted for age, household income, highest level of parental education, and total carotenoid intake (mg/1000 kcal). ResultsRegression modeling revealed that skin carotenoids significantly related to cognition (β = 0.24; P = 0.04) and not to any other BSID-IV subsets. Neither MMN nor VEP outcomes significantly related to skin carotenoids. ConclusionsGreater skin carotenoids were selectively related to cognition, indicating that carotenoids may play a role in cognition in toddlers. Additional research is needed to understand links between skin carotenoids and specific domains of cognitive function and brain health in early life.

Transcriptomic and metabolomic analyses reveal the positive effect of moderate concentration of sodium chloride treatment on the production of β-carotene, torulene, and torularhodin in oleaginous red yeast Rhodosporidiobolus odoratus XQR

Carotenoids, a family of lipid-soluble pigments, have garnered growing interest for their health-promoting benefits and are widely utilized in the food, feed, pharmaceutical, and cosmetic industries. Rhodosporidiobolus odoratus, a representative oleaginous red yeast, is considered a promising alternative for producing high-value carotenoids including β-carotene, torulene, and torularhodin. Here, the impact of varying concentrations of NaCl treatments on carotenoid contents in R. odoratus XQR after 120 h of incubation was examined. The results indicated that, as compared to the control (59.37 μg/gdw), the synthesis of total carotenoids was significantly increased and entirely suppressed under low-to-moderate (0.25 mol/L: 68.06 μg/gdw, 0.5 mol/L: 67.62 μg/gdw, and 0.75 mol/L: 146.47 μg/gdw) and high (1.0, 1.25, and 1.5 mol/L: 0 μg/gdw) concentrations of NaCl treatments, respectively. Moreover, the maximum production of β-carotene (117.62 μg/gdw), torulene (21.81 μg/gdw), and torularhodin (7.04 μg/gdw) was achieved with a moderate concentration (0.75 mol/L) of NaCl treatment. Transcriptomic and metabolomic analyses suggested that the increase in β-carotene, torulene, and torularhodin production might be primarily attributed to the up-regulation of some key protein-coding genes involved in the terpenoid backbone biosynthesis (atoB, HMGCS, and mvaD), carotenoid biosynthesis (crtYB and crtI), and TCA cycle (pckA, DLAT, pyc, MDH1, gltA, acnA, IDH1/2, IDH3, sucA, sucB, sucD, LSC1, SDHA, and fumA/fumB). The present study not only demonstrates a viable method to concurrently increase the production of β-carotene, torulene, torularhodin, and total carotenoids in R. odoratus XQR, but it also establishes a molecular foundation for further enhancing their production through genetic engineering.

Boosting cherry tomato yield, quality, and mineral profile through the application of a plant-derived biostimulant

The present experiment addressed the effects of a plant-derived biostimulant (PDB, Bioup® TF) on fruit quality and composition of two greenhouse cherry tomato cultivars (Caravaggio and Creativo) grown during the autumn-winter. The biostimulant application enhanced the marketable fruit yield up to 1.148 g m−2 of ‘Creativo’ (+16 %) and increased the fruit dry matter, firmness, and chroma (C*), particularly of ‘Caravaggio’ (by 23, 12, and 11 %, respectively). ‘Caravaggio’ also showed the strongest increase in total polyphenols (+26 %) and carotenoid contents (+50 %) in response to the treatment. This trend paralleled the strongest rise of the in vitro antioxidant activity of its fruit extracts, as revealed by the DPPH and FRAP assays. Moreover, the biostimulant treatment resulted in higher concentrations of 10 among 12 minerals analyzed in fresh fruit. This effect was particularly relevant for calcium, manganese, and copper, whereas ‘Caravaggio’ proved the strongest rise for potassium, magnesium, sodium, and zinc. Interestingly, the biostimulant application did not promote or even reduced the concentration of nickel in fresh ‘Caravaggio’ and ‘Creativo’ (-38 %) fruit, respectively. This suggests that the integration of PDBs in the framework of agronomic strategies could assist in producing Ni-poor tomatoes while increasing, at the same time, their levels in health-promoting minerals.

Evaluation of carob tree (Ceratonia siliqua L.) pods, through three different drying techniques, and ultrasonic assisted extraction, for presence of bioactives

The Mediterranean evergreen carob tree (Ceratonia siliqua L.) produces pods, that may be edible and even therapeutic. The purpose of this study was to determine how ethanolic extracts of carob pods from Morocco, prepared with ultrasonic assistance were affected by microwave (525 °C for 2.5 min), hot air (65 °C for 16 h), and spray drying (input and output air temperatures 180 and 90 °C, respectively, feed flow rate 2.5 mL/min and 5 bars, respectively), in terms of their physicochemical composition and biological activity. Colorimetric techniques were utilized to ascertain the phytochemical contents of pod extracts, whereas standardized in vitro methodologies were employed to quantify the antioxidant and antimicrobial activities. Physicochemical analysis showed that microwaved powders of carob pods presented significantly high (p<0.05) values of L* (62.15±0.06) and b* (21.32±0.06), and lower values of a* (4.16±0.03), as compared to spray dried and hot air-dried powders. Significantly high (p<0.05) amounts of ash (3.92±0.05 %), fat (1.48±0.02 %), fiber (7.45±0.12 %) and protein (2.65±0.06 %) were found in microwave dried powders, followed by spray dried and hot air dried. Significant difference in macro and micro minerals among three powders was also observed, as microwave dried powders were found to be significantly high (p<0.05) in Mg, K, Ca, Fe, Zn and Mn, followed by spray dried powders, whereas hot air-dried powders presented lowest values. Similarly, spectrophotometric analysis of phytochemicals revealed that ultrasonic assisted ethanolic extracts of microwave dried powders were found to be highest in total phenolics, flavonoids and carotenoids, with values 69.18±0.15 mg GAE/g, 34.88±0.08 mg QE/g and 24.05±0.15 mg g-1, respectively. In vitro antioxidant and antimicrobial analysis also showed a similar trend as, extracts of microwave dried powders exhibited significantly high (p<0.05) antioxidant and antimicrobial activities, followed by spray dried and hot air-dried. As compared to hot air and spray drying, the microwave drying and ultrasonic assisted extraction using 70 % ethanol as solvent could be employed on carob pods, to obtain powders and extracts, respectively, with minimum degradation of physicochemical characteristics, and maximum retention of nutritional, bioactive and antioxidant contents. Practical applicationsIn recent years, Morocco has become more and more dependent on the use of carob fruit and its powders. Nonetheless, very rare is known about the composition and carob pod quality of those grown in Mediterranean nations. The current study presents a comparison of the effects of three distinct commercial drying methods on the composition and physical characteristics of flour made from carob pods. The study's findings can also be used to evaluate how well information is composed, processed, and preserved for use in future research and commercial applications.

Assessing the Influence of Cumulative Chlorella vulgaris Intake on Broiler Carcass Traits, Meat Quality and Oxidative Stability.

The impacts of cumulative Chlorella vulgaris intake (proportion of microalga in the diet multiplied by the total feed consumed by each bird) on broiler carcass traits, meat quality and oxidative stability were reviewed to identify the optimal intake levels for maximising benefits. Our findings indicate that a cumulative intake of 8.73 g/bird significantly enhances thigh yield, while levels ranging from 8.73 to 401 g/bird optimise carcass weight and overall meat quality. However, higher cumulative levels may reduce carcass dressing percentage due to metabolic inefficiencies. Furthermore, C. vulgaris intake improves the oxidative stability of broiler meat by increasing antioxidant levels and balancing pro- and antioxidants. Including C. vulgaris in broiler diets boosts total carotenoid content, and antioxidant assays confirm that it enhances meat oxidative stability, with low to moderate cumulative intake levels (8.73 to 401 g/bird) providing the best balance of benefits. Optimal oxidative stability and antioxidant properties were observed at a cumulative intake level of 401 g/bird, showing significant improvements in meat antioxidant capacity. Higher levels may lead to diminishing returns or potential negative effects due to the digestibility issues of the microalga. Future research should refine intake models, understand the bioavailability of C. vulgaris nutrients and explore cost-effective methods to enhance its digestibility, to ensure its viability and sustainability as a feed additive.

Low Serum Total Carotenoids and β-Cryptoxanthin Are Associated with Low Lean Body Mass in Older Community-Dwellers in the National Institute for Longevity Sciences–Longitudinal Study of Aging: A 4-Y Longitudinal Study

BackgroundAlthough diets rich in carotenoids are associated with muscle health and a reduced risk of disability, the relationship between carotenoids and low lean body mass has not been fully elucidated. ObjectivesThis study aimed to clarify the relationship between serum carotenoid concentrations and low lean body mass over 4 y in older Japanese community-dwellers. MethodsA total of 750 adults aged ≥60 y participated in the National Institute for Longevity Sciences–Longitudinal Study of Aging. Individuals with a low lean body mass and muscle strength or gait speed at baseline were excluded. Baseline serum α-carotene, β-carotene, β-cryptoxanthin, zeaxanthin, lutein, and lycopene were measured. Low lean body mass was defined as appendicular lean mass relative to the measured height (ALM/ht2) of <7.0 kg/m2 in males and <5.4 kg/m2 in females, according to the criteria of the Asian Working Group for Sarcopenia 2019. A generalized estimating equation was used to estimate the odds ratio and 95% confidence interval for low lean body mass according to tertiles of total and individual carotenoids at baseline, adjusted for sex, age, season, follow-up months, education years, economic status, current smoking status, a history of ischemic heart disease, stroke, hypertension, dyslipidemia, diabetes mellitus, and metabolic equivalents. ResultsLow serum total carotenoids were associated with low ALM/ht2, and the odds ratios of low ALM/ht2 in the third tertile of total carotenoids were significantly lower than those in the first tertile after adjusting for covariates. The odds ratios of low ALM/ht2 in the third tertile of β-cryptoxanthin were significantly associated with those in the first tertile after adjusting for covariates (P = 0.03); however, no trend was observed for this relationship. ConclusionsThese findings indicate that low serum total carotenoids and serum β-cryptoxanthin are associated with low lean body mass in older Japanese community-dwellers.

Phytochemical and Antioxidant Profiling of Chilli (Capsicum annuum L.) Landraces from Hilly Regions of India

The present study was carried out to assess the phytochemical and antioxidant potential of 24 chilli landraces grown in hilly regions of India viz. Himachal Pradesh &amp; Assam and genotypes were evaluated for different phytochemical parameters and antioxidant assays. Highest total sugar (3.43 %), reducing sugar (2.22 %), polyphenolic content (153.85 mg /100g GAE), total carotenoids (101.66 mg/100g), ascorbic acid (12.85 mg/100g) and reducing power assay (70.76 mM/g TE) were found in the genotype ‘Chilli SC-1’, while ‘Chilli CHI-15’ was found superior for total flavonoid content (547.01 mg/100g QE). The genotype, ‘Chilli SC-1’followed ‘Chilli L-2’ were found best owing to their Trolox equivalent antioxidant activity. The above results were also confirmed with spectral studies using FT-IR spectroscopy and genotype ‘Chili SC-1’ was found best in all the concerned parameters as the highest peaks of the respective sample were observed concerning all other samples. Further, principal component analysis indicated that the genotype ‘Chilli SC-1’, ‘Chilli LC-2’, ‘Chilli AC-9’ and ‘Chilli AC-10’ are the major contributors to divergence within different quality traits under study.

Machine learning-driven assessment of biochemical qualities in tomato and mandarin using RGB and hyperspectral sensors as nondestructive technologies.

Estimation of fruit quality parameters are usually based on destructive techniques which are tedious, costly and unreliable when dealing with huge amounts of fruits. Alternatively, non-destructive techniques such as image processing and spectral reflectance would be useful in rapid detection of fruit quality parameters. This research study aimed to assess the potential of image processing, spectral reflectance indices (SRIs), and machine learning models such as decision tree (DT) and random forest (RF) to qualitatively estimate characteristics of mandarin and tomato fruits at different ripening stages. Quality parameters such as chlorophyll a (Chl a), chlorophyll b (Chl b), total soluble solids (TSS), titratable acidity (TA), TSS/TA, carotenoids (car), lycopene and firmness were measured. The results showed that Red-Blue-Green (RGB) indices and newly developed SRIs demonstrated high efficiency for quantifying different fruit properties. For example, the R2 of the relationships between all RGB indices (RGBI) and measured parameters varied between 0.62 and 0.96 for mandarin and varied between 0.29 and 0.90 for tomato. The RGBI such as visible atmospheric resistant index (VARI) and normalized red (Rn) presented the highest R2 = 0.96 with car of mandarin fruits. While excess red vegetation index (ExR) presented the highest R2 = 0.84 with car of tomato fruits. The SRIs such as RSI 710,600, and R730,650 showed the greatest R2 values with respect to Chl a (R2 = 0.80) for mandarin fruits while the GI had the greatest R2 with Chl a (R2 = 0.68) for tomato fruits. Combining RGB and SRIs with DT and RF models would be a robust strategy for estimating eight observed variables associated with reasonable accuracy. Regarding mandarin fruits, in the task of predicting Chl a, the DT-2HV model delivered exceptional results, registering an R2 of 0.993 with an RMSE of 0.149 for the training set, and an R2 of 0.991 with an RMSE of 0.114 for the validation set. As well as for tomato fruits, the DT-5HV model demonstrated exemplary performance in the Chl a prediction, achieving an R2 of 0.905 and an RMSE of 0.077 for the training dataset, and an R2 of 0.785 with an RMSE of 0.077 for the validation dataset. The overall outcomes showed that the RGB, newly SRIs as well as DT and RF based RGBI, and SRIs could be used to evaluate the measured parameters of mandarin and tomato fruits.

Response of postharvest treatments on shelf life, biochemical and microbial quality of banana variety Red Banana.

The popular Red Banana variety faces transportation challenges and has a limited postharvest shelf life due to its ripe fruits being less resistant and being a climacteric fruit. This study aims to prolong the shelf life of Red Banana fruits through different postharvest treatments. Fruit bunches of Red Banana were harvested at the mature green stage, separated into hands, precooled, subjected to 12 treatments and stored in corrugated fibre board boxes till the end of shelf life under ambient conditions. Fruits coated with 10% bee wax + 0.5% clove oil (T4), fruits subjected to coating with 10% bee wax and packaging with potassium permanganate (T9) and fruits dipped in hot water at 50 °C for 10 min. and packaging with potassium permanganate (T11) registered highest shelf life of 18.67 days. The highest TSS of 26.33°Brix was noticed in fruits stored with potassium permanganate (T8) after 12.67 days of storage and lowest titratable acidity of 0.19% and the highest sugar-acid ratio of 79.76 was noticed in control (T12) after 11.33 days of storage. Moreover, the highest vitamin C content (7.74 mg 100 g?¹), total sugar content (18.47%), reducing sugar content (15.49%), total carotenoid content (24.13 µg 100 g-1) was noticed in treatment T7 (hot water dipping at 50 °C for 10 min.) after 17.67 days, T10 (coating with 40% aloe vera extract and packaged with potassium permanganate) after 13.33 days, T4 (coating with 10% bee wax + 0.5% clove oil) after 18.67 days and T9 (coating with 10% bee wax + potassium permanganate) after 18.67 days of storage respectively. Furthermore, the lowest fungal and bacterial count was observed in treatments T2 (dipping in 30ppm sodium hypochlorite solution), T7 (hot water dipping at 50 °C for 10 min.), T9 (coating with 10% bee wax + potassium permanganate) and T10 (coating with 40% aloe vera extract + potassium permanganate) .

Anti-browning action of melatonin is dependent on the type of tissue in minimally processed sweet potatoes

This study explored the impact of exogenous melatonin on oxidative damage, protective mechanisms against oxidation, and reactions leading to browning, as well as the accumulation of antioxidants in minimally processed white-fleshed and orange sweet potato roots. Sweet potato roots with white and orange pulp were subjected to minimal processing and immersion in melatonin solutions at concentrations of 0, 10, 100, and 1000 µmol L−1. Following packaging, these were stored at 5 ± 2 °C for 20 days. Results indicate that increasing melatonin concentrations significantly reduced browning symptoms in both white and orange sweet potato slices. This reduction was associated with decreased levels of hydrogen peroxide (H2O2), thiobarbituric acid-reactive substances (TBARs), and electrolyte leakage, indicating reduced cell membrane damage. Enhanced protection was observed through increased activity of antioxidant enzymes superoxide dismutase, catalase, and ascorbate peroxidase and higher levels of antioxidant metabolites, including vitamin C and phenolic compounds, as confirmed by in vitro assays for antioxidant capacity (FRAP and DPPH), however, the levels of total carotenoids, anthocyanins, and yellow flavonoids did not show a significant difference between the melatonin treatments. Notably, sweet potato slices treated with higher melatonin doses of 100 and 1000 µmol L−1 exhibited reduced phenylalanine ammonia-lyase activity and phenolic compound accumulation. This effect, coupled with lower polyphenol oxidase (PPO) and peroxidase (POD) activities, likely contributed to prolonged preservation quality by maintaining cellular redox homeostasis.

Effect of ohmic heating on the extraction of biocompounds from aqueous and ethanolic suspensions of Pavlova gyrans

Electric field technology has been highlighted as a promising strategy in the permeabilization of cell membranes and the corresponding bioactive release. In this work, aqueous and ethanolic suspensions of Pavlova gyrans were subjected to moderate electric fields (MEF) to promote rapid heating due to Ohmic Heating (OH) effect. Two approaches were tested: i) OH assisted extraction in a temperature range between 25 ºC and 85 ºC, and ii) OH pretreatment at 25 ºC and 55 ºC followed by solvent extraction. OH treatment at 55 ºC (performed in less than 10 s) in aqueous suspensions promoted a marked increase in the release of organic matter (2.1-fold), chlorophyll a (41.1-fold) and total carotenoids (56.6-fold) when compared to the freeze-thaw cycles (FTC ≈ 3 hours). OH-pretreated biomass subjected to a two-step passive extraction improved the release of proteins and chlorophylls over incubation (p < 0.05) when compared to untreated biomass. This procedure increased 2.2-, 3.9- and 31.9-fold the content of organic matter, protein and chlorophyll a, respectively, in comparison to the FTC procedure. This work presented the OH effect as a promising strategy for enhanced disruption and release of intracellular microalgae compounds.

Aruncus dioicus var. kamtschaticu: A Newly Identified Source of Lactucaxanthin (ε,ε-Carotene-3,3′-diol)

Green leafy vegetables are rich in lipophilic metabolites such as carotenoids, phytosterols, tocopherols, and fatty acids, known for their significant health benefits. Goat’s beard (Aruncus dioicus var. kamtschaticus), a wild leafy vegetable native to Ulleungdo Island, South Korea, is reported to possess various biological activities and bioactive compounds. However, the content and profiles of lipophilic metabolites, especially carotenoids, have not been reported. This study investigated the composition of lipophilic metabolites in the foliage of goat’s beard using liquid chromatography–diode-array detection–mass spectrometry, gas chromatography–mass spectrometry, and gas chromatography–flame ionization detection. Five carotenoids (violaxanthin, neoxanthin, lactucaxanthin, lutein, β-carotene) and α-tocopherol were identified and quantified using liquid chromatography–diode-array detection–mass spectrometry. Lactucaxanthin, previously discovered in lettuce, was identified for the first time in goat’s beard foliage, with a higher concentration (45.42 ± 0.80 µg/g FW) compared to red lettuce (19.05 ± 0.67 µg/g FW). Furthermore, total carotenoids and α-tocopherol contents were higher in goat’s beard than in red lettuce. Gas chromatography–mass spectrometry analysis showed the presence of three phytosterols, namely, campesterol (3.53 ± 0.20 µg/g FW), stigmasterol (65.30 ± 4.87 µg/g FW), and β-sitosterol (89.54 ± 2.46 µg/g FW). Gas chromatography–flame ionization detection analysis revealed the presence of five essential fatty acids, with α-linolenic acid (57.03 ± 0.47%) being the most abundant, contributing to a favorable polyunsaturated FA/saturated FA ratio. These findings underscore the nutritional potential of a goat’s beard, suggesting its promising use in dietary supplements and the commercial extraction of valuable lipophilic antioxidants, particularly lactucaxanthin, for nutraceuticals and functional foods.