Melanin Inhibitory Effect of Tuber himalayense Isolated in Incheon, Korea.

There has been a growing interest in skin beauty and antimelanogenic products. Melanogenesis is the process of melanin synthesis whereby melanocytes are activated by UV light or hormone stimulation to produce melanin. Melanogenesis is mediated by several enzymes, such as tyrosinase (TYR), microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TRP-1), and TRP-2. In this study, we investigated the effect of Tuber himalayense extract on melanin synthesis in α-melanocyte-stimulating hormone (α-MSH)-treated B16F10 melanoma cells. We confirmed that T. himalayense extract was not toxic to α-MSH-treated B16F10 melanoma cells and exhibited a significant inhibitory effect on melanin synthesis at concentrations of 25, 50, and 100 µg/ml. Additionally, the T. himalayense extract inhibited melanin, TRP-1, TRP-2, tyrosinase, and MITF, which are enzymes involved in melanin synthesis, in a concentration-dependent manner. Furthermore, T. himalayense extract inhibited the mitogen-activated protein kinase (MAPK) pathways, such as extracellular signal-regulated kinase-1/2 (ERK), c-Jun N-terminal kinase (JNK), and p38. Therefore, we hypothesized that various components of T. himalayense extract affect multiple factors involved in melanogenesis in B16F10 cells. Our results indicate that T. himalayense extract could potentially be used as a new material for preparing whitening cosmetics.

How physicochemical and nutritional traits of potatoes may vary under field conditions over long periods.

BACKGROUND: Potato is the most important non-grain crop worldwide, whose quality characteristics are always affected by temporal and spatial variability. Knowledge of the performance consistency of quality characteristics over long periods could prove very important to identify which quality traits are less variable over time, and therefore provide greater guarantees of stability. In this research, variations in physicochemical and nutritional traits of tubers over five consecutive growing seasons of two potato genotypes (Arizona and Vogue) were monitored in two locations. RESULTS: Although qualitative performances of genotypes fluctuated across the seasons in both locations, two physicochemical traits (pH and dry matter content) and starch content showed less variability throughout the five seasons compared to total soluble solids and most of the nutritional traits (namely reducing sugars, citric acid, vitamin C, total phenolics and antioxidant capacity), which were considerably influenced by weather conditions. CONCLUSION: The results suggest that pH, dry matter content and starch content traits could be used advantageously in studies of temporal stability in potatoes. This approach could prove useful in providing scientific support for the setup of potato protected geographical identifications. © 2024 Society of Chemical Industry.

Deep learning-based characterization and redesign of major potato tuber storage protein.

Potato is one of the most important crops worldwide, to feed a fast-growing population. In addition to providing energy, fiber, vitamins, and minerals, potato storage proteins are considered as one of the most valuable sources of non-animal proteins due to their high essential amino acid (EAA) index. However, low tuber protein content and limited knowledge about potato storage proteins restrict their widespread utilization in the food industry. Here, we report a proof-of-concept study, using deep learning-based protein design tools, to characterize the biological and chemical characteristics of patatins, the major potato storage proteins. This knowledge was then employed to design multiple cysteines on the patatin surface to build polymers linked by disulfide bonds, which significantly improved viscidity and nutrient of potato flour dough. Our study shows that deep learning-based protein design strategies are efficient to characterize and to create novel proteins for future food sources.

Characterization of the physiological parameters, effective components, and transcriptional profiles of Polygonum multiflorum Thunb. Under pH stress.

Polygonum multiflorum Thunb. is a traditional Chinese medicine with extensive distribution and robust adaptability, but comprehensive research on its acid and alkali resistance is presently lacking. This study aimed to analyze the effects of 5 months of continuous pH stress on the physiological and photosynthetic parameters of P. multiflorum, and the content of effective components. Results revealed that pH stress significantly influenced the normal growth, physiological functions, and photosynthetic indicators of P. multiflorum. At soil pH 4.5, the tubers of P. multiflorum exhibited the highest levels of 2,3,5,4'-tetrahydroxy stilbene-2-O-ß-d-glucoside (THSG) and total anthraquinones at 5.41% and 0.38%, respectively. However, increased soil pH significantly reduced the content of THSG and total anthraquinones. Reference-free transcriptome analysis was further conducted on P. multiflorum treated at pH 4.5 and 9.5, generating a total of 47,305 unigenes with an N50 of 2118 bp, of which 31,058 (65.65%) were annotated. Additionally, 2472 differentially expressed genes (DEGs) were identified. Among them, 17 DEGs associated with the biosynthesis of THSG and anthraquinones were screened. A comprehensive analysis of differential gene expression and effective component content demonstrated a significant positive correlation between the content of effective components and the 14 DEGs' expression but a negative correlation with soil pH. This study highlighted the influence of varying soil pH values on the effective component content of P. multiflorum. Specific acidic conditions proved beneficial for the synthesis and accumulation of THSG and total anthraquinones in P. multiflorum, thereby enhancing the quality of the medicinal material.

Real-Time Monitoring of Translocation, Dissipation, and Cumulative Risk of Maleic Hydrazide in Potato Plants and Tubers by Ion Exclusion Chromatography.

In this paper, a high-performance ion exclusion chromatographic (ICE) method was developed and applied for monitoring maleic hydrazide (MH) translocation in complex potato plant tissue and tuber matrices. After middle leaf uptake, most MH was trapped and dissipated in the middle leaf, and the rest was transported to other parts mainly through the phloem. Soil absorption significantly reduced the uptake efficiency of the root system, in which MH was partitioned to dissipate in root protoplasts or transfer through the xylem and persisted in the plant. Tuber uptake enabled MH to remain in the flesh and maintain stable levels under storage conditions, but during germination, MH was translocated from the flesh to the growing buds, where it dissipated through the short-day photoperiodic regime. The results demonstrated successful application of the ICE method and provided necessary insights for real-time monitoring of MH translocation behavior to effectively improve potato edible safety.

Cucurbitane triterpenes from Hemsleya chinensis tubers and their anti-inflammatory activities.

Six new cucurbitane-type triterpenes, hemchinins A-F (1-6), together with thirteen known ones (7-19) were isolated from ethyl acetate extraction of Hemsleya chinensis tubers. Compounds 1-2 were a group of cucurbitane triterpenes possessing an infrequent pentacyclic framework. Their structures were established by comprehensive UV, IR, HRMS, 1D/2D NMR, and ECD analyses. Bioassay results showed that most isolated compounds exhibited anti-inflammatory actions, in which compounds 13 and 15 exhibited stronger activities at 6.25 µM, with NO inhibition rates of 49.00 ± 0.05% and 48.40 ± 0.10%, respectively.

Resistant starch from sweet potatoes: Recent advancements and applications in the food sector.

In tropical and subtropical areas, tuber and root crops are staple foods and a key source of energy. Sweet potato (SP) is currently regarded as one of the world's top ten foods because of its diverse sizes, shapes, color, and health benefits. The resistant starch (RS) content of SP is substantial. It is predicted to become the cheapest item in the food industry due to its extensive variety, food stability, emulsifier and fat substitution capabilities, and as filler. As a result, interest in SP-sourced RS has recently increased. Due to their unique nutritional and functional qualities, novelty has become a popular research focus in recent years. This review will summarize the current understanding of SP starch components and their impact on the technological and physicochemical properties of produced starch for commercial viability. The importance of sweet potato RS in addressing future RS demand sustainability is emphasized. SPs are a viable alternative to tubers as a sustainable raw material for RS production. It has an advantage over tubers because of its intrinsic nutritional value and climatic endurance. Thermal, chemical, and enzymatic treatments are effective RS manufacturing procedures. The adaptability of sweet potato RS allows for a wide range of food applications.

Metabolite profiling of tubers of an early- and a late-maturing potato line and their grafts.

INTRODUCTION: Earliness of tuberisation and the quality of potato tubers are important traits in potato breeding. The qualitative traits rely on the metabolite profile of tubers, which are storage organs and net importers of assimilates. Thus, the quality of tubers largely depends on the metabolites transported from leaves to developing tubers. OBJECTIVES: To test the influence of canopy on the quality of tubers by metabolite profiling of tubers of an early- and a late-maturing potato line and their grafts. METHODS: Potatoes were grown under greenhouse conditions, grafted and the tubers harvested at the end of the scions' vegetation period. Metabolite profiling of freshly harvested tubers was performed using gas chromatography coupled with mass spectrometry. Statistical analyses were applied to determine the significant differences between the different tubers. RESULTS: 99 metabolites were identified and an additional 181 peaks detected in chromatograms, out of which 186 were polar and 94 non-polar compounds. The concentrations of 113 metabolites were significantly different in the tubers from the early-maturing CE3130 and the late-maturing CE3027 line. Hetero-grafting resulted in considerable changes in the metabolite content of tubers. Especially, the effect of CE3027 on the metabolite composition of tubers formed on CE3130 rootstocks was readily apparent. Nevertheless, many compounds were present at similar levels in the tubers of hetero-grafted plants as was found in the tubers of their scion counterparts. CONCLUSION: Hetero-grafting resulted in many compounds at similar concentrations in rootstock tubers as in scion tubers suggesting that these are transported from the source leaves to tubers.

Comparative Proteomics of Potato Cultivars with a Variable Dormancy Period.

The control of the duration of the dormancy phase is a significant challenge in the potato industry and for seed producers. However, the proteome landscape involved in the regulation of the length of the dormancy period over potato cultivars remains largely unexplored. In this study, we performed for the first time a comparative proteome profiling of potato cultivars with differential duration of tuber dormancy. More specifically, the proteome profiling of Agata, Kennebec and Agria commercial potato varieties with short, medium and medium-long dormancy, respectively, was assessed at the endodormancy stage using high-resolution two-dimensional electrophoresis (2-DE) coupled to reversed-phase liquid chromatography-tandem mass spectrometry (LC-TripleTOF MS/MS). A total of 11 proteins/isoforms with statistically significant differential abundance among cultivars were detected on 2-DE gels and confidently identified by LC-TripleTOF MS/MS. Identified proteins have known functions related to tuber development, sprouting and the oxylipins biosynthesis pathway. Fructokinase, a mitochondrial ADP/ATP carrier, catalase isozyme 2 and heat shock 70 kDa were the proteins with the strongest response to dormancy variations. To the best of our knowledge, this study reports the first candidate proteins underlying variable dormancy length in potato cultivars.

Quantitation of Toxic Steroidal Glycoalkaloids and Newly Identified Saponins in Post-Harvest Light-Stressed Potato (Solanum tuberosum L.) Varieties.

Although domesticated potatoes contain a large variety of steroidal glycoalkaloids (SGAs) and saponins, in the past, many research projects mainly focused on the two major SGAs, α-solanine and α-chaconine. This study investigates the quantitative changes, induced by post-harvest LED light exposure, of six SGAs and four saponins in 12 potato cultivars at three different time points (1, 7, and 16 days), by using ultra-performance liquid chromatography tandem mass spectrometry. Altogether, SGA contents of 3.0-17.1 mg/100 g fresh weight (FW) could be observed in the analyzed tubers with potato varieties highly exceeding the newly discussed safety limit of 10 mg/100 g. The overall contents of 0.1-5.4 mg/100 g FW of the so far barely studied saponins, like protoneodioscin or barogenin-solatrioside, highly differed between the assayed potato cultivars. Furthermore, cultivar-specific regulations of SGAs and saponins could be observed due to light exposure.

Study of the molecular-structural composition of alcoholic extracts of radio-induced potato tubers by mass spectrometry and EPR.

This article presents data on electron paramagnetic resonance (EPR) and mass spectrometric analysis of potato tubers, irradiated with gamma rays, in order to examine and identify changes in the molecular composition of organic matter following radiation exposure. The products of the Maillard reaction were compared with the products of intramolecular radiolysis of organic constituents of potatoes. The presence of free radicals was verified using EPR. DDPM (2,3-dihydro-3,5-dihydroxy-6-methyl-4 (H) -pyran-4-one) was among the radiolysis products detected via mass spectrometry, which points to the intramolecular dehydration of potato carbohydrates. EPR signals indicate single-electron transitions of the semidione radical anionic molecular compounds. It has been shown that irradiation with gamma rays significantly destroys the carbohydrate, lipid, keto-carotene and amino acid molecules of potatoes.

Screening of Acrylamide of Par-Fried Frozen French Fries Using Portable FT-IR Spectroscopy.

Current assays for acrylamide screening rely heavily on LC-MS/MS or GC-MS, techniques that are not suitable to support point of manufacturing verification because it can take several weeks to receive results from a laboratory. A portable sensor that can detect acrylamide levels in real-time would enable in-house testing to safeguard both the safety of the consumer and the economic security of the agricultural supplier. Our objective was to develop a rapid, accurate, and real-time screening technique to detect the acrylamide content in par-fried frozen French fries based on a portable infrared device. Par-fried French fries (n = 70) were manufactured at times ranging from 1 to 5.5 min at 180 °C to yield a wide range of acrylamide levels. Spectra of samples were collected using a portable FT-IR device operating from 4000 to 700 cm-1. Acrylamide was extracted using QuEChERS and quantified using uHPLC-MS/MS. Predictive algorithms were generated using partial least squares regression (PLSR). Acrylamide levels in French fries ranged from 52.0 to 812.8 µg/kg. The best performance of the prediction algorithms required transformation of the acrylamide levels using a logarithm function with models giving a coefficient of correlation (Rcv) of 0.93 and RPD as 3.8, which means the mid-IR model can be used for process control applications. Our data corroborate the potential of portable infrared devices for acrylamide screening of high-risk foods.

Nutrient expert system optimizes fertilizer management to improve potato productivity and tuber quality.

BACKGROUND: Improving potato productivity and quality plays an important role in enhancing global food security and human health. However, inappropriate fertilizer management negatively affects potato growth and tuber development, especially in developing countries where there are large numbers of smallholders without modern soil testing equipment. Nutrient Expert (NE), a new and convenient fertilization decision system, was evaluated in the present study by conducting four site-years field experiments in Northeast China, aiming to determine its effectiveness and applicability for potato production relative to local farmers' practice (FP) and fertilizer recommendation based on soil testing (ST). RESULTS: The excessive fertilization at planting promoted seedling growth for potato plants in FP. Nevertheless, superior plant growth and tuber development were observed in NE at the middle and later growing stages, by optimizing fertilizer input and implementing split fertilization. Overall, compared to FP, the NE system increased total and marketable tuber yields by 12-15% and 16-26%, respectively, at the same time as obtaining 19-31% higher net returns and enhanced fertilizer use efficiencies. Moreover, NE improved tuber quality by increasing the contents of starch, soluble protein and vitamin C and decreasing reducing sugar content relative to FP, as well as increasing starch yields by 23-52%. The ST method also showed comprehensive improvements in potato performances compared to FP, although it did not show any advantages compared to NE system. CONCLUSION: The NE system improved potato productivity and tuber quality by optimizing fertilization management, which is an effective and promising alternative to the ST method for potato production in China and other developing countries. © 2021 Society of Chemical Industry.

Nitrate and nitrite pathways and dynamic changes in bacterial communities during beet sugar processing.

BACKGROUND: Bacterial community successions were surveyed during the processing stages of sugar production using high-throughput sequencing methods. Furthermore, the correlation between bacterial community and nitrate/nitrite content in beet sugar processing were investigated. RESULTS: In an analysis of the V3-V4 region of the 16S rDNA gene, 254 122 effective sequences were obtained from samples, which included sugar beet, cossettes, diffusion juice, second-phase diffusion juice, light juice and thick juice. The results showed that dominant genera included Pantoea, Pseudomonas, Leuconostoc and Burkholderia. Moreover, significant changes in bacterial communities were observed in samples. Regarding the relevant nitrogen metabolic potential, this study revealed communities with the ability for nitrate and nitrite metabolism. Furthermore, a shaking experiment involving diffusion juice and second-phase diffusion juice was performed, and results showed that the nitrate level declined 73% and 98% in 36 h, respectively. These results suggested that the bacterial communities contribute to nitrate and nitrite transformation. CONCLUSION: This study illustrated that the bacterial communities and their specific effects on the formation of nitrate and nitrite during beet sugar processing. The results presented the basic concept involving the nitrate- and nitrite-forming pathways directly related to the mechanism of bacterial community growth. This study could facilitate an understanding of the correlation between nitrite content and microorganisms to guide beet sugar manufacturers regarding the control of nitrite and nitrate content. © 2021 Society of Chemical Industry.

Organ-specific, integrated omics data-based study on the metabolic pathways of the medicinal plant Bletilla striata (Orchidaceae).

BACKGROUND: Bletilla striata is one of the important species belonging to the Bletilla genus of Orchidaceae. Since its extracts have an astringent effect on human tissues, B. striata is widely used for hemostasis and healing. Recently, some other beneficial effects have also been uncovered, such as antioxidation, antiinflammation, antifibrotic, and immunomodulatory activities. As a key step towards a thorough understanding on the medicinal ingredient production in B. striata, deciphering the regulatory codes of the metabolic pathways becomes a major task. RESULTS: In this study, three organs (roots, tubers and leaves) of B. striata were analyzed by integrating transcriptome sequencing and untargeted metabolic profiling data. Five different metabolic pathways, involved in polysaccharide, sterol, flavonoid, terpenoid and alkaloid biosynthesis, were investigated respectively. For each pathway, the expression patterns of the enzyme-coding genes and the accumulation levels of the metabolic intermediates were presented in an organ-specific way. Furthermore, the relationships between enzyme activities and the levels of the related metabolites were partially inferred. Within the biosynthetic pathways of polysaccharides and flavonoids, long-range phytochemical transportation was proposed for certain metabolic intermediates and/or the enzymes. CONCLUSIONS: The data presented by this work could strengthen the molecular basis for further studies on breeding and medicinal uses of B. striata.

Borate and phosphite treatments of potato plants (Solanum tuberosum L.) as a proof of concept to reinforce the cell wall structure and reduce starch digestibility.

Potatoes are one of the main sources of carbohydrates in human diet, however they have a high glycaemic index (GI). Hence, developing new agricultural and industrial strategies to produce low GI potatoes represents a health priority to prevent obesity and related diseases. In this work, we investigated whether treatments of potato plants with elicitors of plant defence responses can lead to a reduction of tuber starch availability and digestibility, through the induction of cell wall remodelling and stiffening. Treatments with phosphites (KPhi) and borate were performed, as they are known to activate plant defence responses that cause modifications in the architecture and composition of the plant cell wall. Data of suberin autofluorescence demonstrated that potato plants grown in a nutrition medium supplemented with KPhi and borate produced tubers with a thicker periderm, while pectin staining demonstrated that KPhi treatment induced a reinforcement of the wall of storage parenchyma cells. Both compounds elicited the production of H2O2, which is usually involved in cell-wall remodelling and stiffening reactions while only KPhi caused an increase of the total content of phenolic compounds. A two-phase digestion in vitro assay showed that treatment with KPhi determined a significant decrease of the starch hydrolysis rate in potato tubers. This work highlights the ability of cell wall architecture in modulating starch accessibility to digestive enzymes, paving the way for new agronomic practices to produce low GI index potatoes.

Bioactive Betalain Extracts from Cactus Pear Fruit Pulp, Beetroot Tubers, and Amaranth Leaves.

Natural food items and the additional benefits they provide have received considerable attention in recent years. Betalains are nutritious pigments which have valuable biological properties, e.g., antioxidant and free radical scavenging activity. In this study, aqueous betalain extracts were obtained from different coloured cactus pears (purple, red/pink, and orange), amaranth, and beetroot, with and without the addition of ascorbic acid, microwave-heated, and freeze-dried and subsequently analysed by thin layer chromatography (TLC). Beetroot samples without the addition of ascorbic acid (AA) had lower phenols, flavonoids, and ascorbic acid content than beetroot samples extracted with the addition of AA. Amaranth had significantly higher contents of antioxidants than all the other plants. Results for phenolic compounds showed that there were no significant differences between cactus pear cultivars, however, significant differences were seen between the two beetroot samples (microwave-heated with and without AA) as well as amaranth. For flavonoid compounds, amaranth had significantly higher values than all other samples. The lowest flavonoid content was found in beetroot without AA (0.49 mgCE/g). For ascorbic acid, significant differences were noticed between amaranth (71.71 mg/100 g) and samples from cactus pear and beetroot. TLC results showed that purple and red cactus pear samples had the most vivid colours, a reflection of the high betacyanin and betaxanthin contents in the cultivars. Moreover, extracts from cactus pear, beetroot, and amaranth were classified according to a decision tree which was designed by the Code of Federal Regulations/Food Additives Regulation of the EU. The classification of betalain pigment extracts as colouring foods was achieved through enrichment factor calculations and the colourant decision tree. The results showed that the betalain pigment extraction method used is inexpensive, time-saving, energy-saving, non-toxic, and chemical solvent free and yields high concentrations of betalains.

Investigation of phytochemical composition and metabolite profiling in vivo of Beta vulgaris L.

RATIONALE: Beta vulgaris L. has attracted increasing attention because of its broad application. The root of B. vulgaris L. (beetroot) possesses many excellent biological properties such as antianemic, anti-inflammatory, antihypertensive, antioxidant, anticarcinogenic, antipyretic, antibacterial, detoxicant, and diuretic. The chemical constituents of beetroot play a major role in the research on beetroot application and development. At present, no systematic identification study that focuses on the chemical constituents of beetroot has been reported. METHODS: This study investigated a three-step strategy comprising phytochemical profiling, prototype profiling, and metabolism of its correlative metabolites in vivo using ultra-performance liquid chromatography tandem quadruple time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). RESULTS: UPLC-QTOF-MS/MS technique proved to be a rapid, sensitive, and reliable method for monitoring the specific ingredients as well as the whole chemical constituents in beetroot. In sum, 95 phytochemical compounds, 51 prototype compounds, and 37 derived metabolites in vivo were found in beetroot. CONCLUSIONS: The main metabolic pathways were sulfonation, glucuronidation, methylation/sulfonation, and methylation. The present findings provided the phytochemical basis both in vitro and in vivo for future application.

Enhanced antitumor activity of inulin-capped Se nanoparticles synthesized using Jerusalem artichoke tubers.

An inulin polysaccharide with a molecular weight of ~ 2600 Da was derived from Jerusalem artichoke tubers and referred to as "JAP". Previous studies have shown that inulin can improve glucose tolerance and the liver lipid profile; however, its antitumor activity remains to be examined in detail. Therefore, to investigate the possible improvement of the antitumor activity of JAP, a novel nanostructured biomaterial was constructed by capping Se nanoparticles with JAP using sodium selenite, via a redox reaction with ascorbic acid, and referred to as "JAP-SeNPs". Transmission electron microscopy revealed that the average diameter of JAP-SeNPs is ~ 50 nm, and the C:Se mass ratio in JAP-SeNPs was found to be 15.4:1 by energy-dispersive X-ray spectroscopy. The well-dispersed JAP-SeNPs exhibited a significant in vitro antiproliferative effect on mouse forestomach carcinoma cells at a concentration of 400 µg/mL when incubated for 48 h, with an inhibition rate of 41.5%. Moreover, 38.9% of later apoptotic cells were observed. These results reveal that a combination of Se and JAP can effectively enhance the antitumor activity of polysaccharides obtained from Jerusalem artichoke tubers.

Optimization of diosgenin extraction from Dioscorea deltoidea tubers using response surface methodology and artificial neural network modelling.

INTRODUCTION: Dioscorea deltoidea var. deltoidea (Dioscoreaceae) is a valuable endangered plant of great medicinal and economic importance due to the presence of the bioactive compound diosgenin. In the present study, response surface methodology (RSM) and artificial neural network (ANN) modelling have been implemented to evaluate the diosgenin content from D. deltoidea. In addition, different extraction parameters have been also optimized and developed. MATERIALS AND METHODS: Firstly, Plackett-Burman design (PBD) was applied for screening the significant variables among the selected extraction parameters i.e. solvent composition, solid: solvent ratio, particle size, time, temperature, pH and extraction cycles on diosgenin yield. Among seven tested parameters only four parameters (particle size, solid: solvent ratio, time and temperature) were found to exert significant effect on the diosgenin extraction. Moreover, Box-Behnken design (BBD) was employed to optimize the significant extraction parameters for maximum diosgenin yield. RESULTS: The most suitable condition for diosgenin extraction was found to be solid: solvent ratio (1:45), particle size (1.25 mm), time (45 min) and temperature (45°C). The maximum experimental yield of diosgenin (1.204% dry weight) was observed close to the predicted value (1.202% dry weight) on the basis of the chosen optimal extraction factors. The developed mathematical model fitted well with experimental data for diosgenin extraction. CONCLUSIONS: Experimental validation revealed that a well trained ANN model has superior performance compared to a RSM model.