Search Results (39)

Oxalis tuberosa (Oca) is traditionally cultivated in the high Andean regions of Peru and represents a promising alternative source of starch with potential industrial uses, ranking among the most essential tubers after the potato. This study aimed to evaluate the physicochemical, morphological, techno-functional, and thermal properties of starch isolated from three specific varieties of Oca (yellow, black, and white) harvested at the Ccanccayllo production center in Andahuaylas, Peru. The isolated starches exhibited high purity, characterized by high luminosity (L* > 92.28) and a whiteness index exceeding 92.10. Moisture content ranged from 9.36% to 10.01%, correlating with low water activity (a_w = 0.44), indicating stability. Notably, the amylose content was significantly higher than that of other previously studied Oca varieties. This composition contributed to a favorable water absorption capacity, solubility index, swelling power, and viscosity, with the white variety displaying superior functional performance. Colloidal stability in aqueous media was moderate, as indicated by zeta potential analysis. Particle size analysis revealed granules ranging from 26.32 to 27.74 μm, with elongated and oval morphologies confirmed by SEM, displaying characteristic functional groups. Thermal analysis (DSC) demonstrated gelatinization temperatures between 52.73 and 53.12 °C and enthalpies ranging from 4.92 to 6.11 J/g, while Thermogravimetric Analysis (TGA) indicated thermal degradation up to approximately 74–80%. These findings suggest that the studied Oca starches possess significant potential for application in the food and pharmaceutical industries due to their distinct functional properties. Full article

The microencapsulation of plant bioactive compounds by spray drying enhances their stability and controlled delivery in food systems. In this study, flaxseed hydrocolloid (Linum usitatissimum L.) was evaluated as a natural wall material for encapsulating phenolic extracts from mashua (Tropaeolum tuberosum Ruiz & Pav.) and oca (Oxalis tuberosa Molina). Microcapsules were produced using hydrocolloid concentrations of 2.5–10%. The resulting particles showed low moisture content (3.79–5.42%), low water activity (0.31–0.39), and high solubility (90.94–96.45%). Encapsulation efficiency ranged from 78.67 to 62.32% for mashua and from 71.94 to 40.45% for oca, decreasing with increasing wall material concentration. Phenolic content ranged from 14.48 to 11.47 mg GAE/g (mashua) and 8.52 to 4.82 mg GAE/g (oca), with antioxidant capacity between 293.19–143.77 and 84.49–10.33 µmol TE/g, respectively. Particle size ranged from 4.02–10.50 µm (mashua) and 3.93–4.82 µm (oca), and zeta potential values (−37.86 to −27.55 mV) indicated good colloidal stability. Release kinetics showed a biphasic profile and were predominantly diffusion-controlled. The Higuchi model showed significant diffusion (p < 0.05), while the Korsmeyer–Peppas analysis indicated mainly Fickian diffusion (n = 0.234–0.426) with anomalous transport at higher mashua concentrations. These results demonstrate that flaxseed hydrocolloid is an effective and sustainable wall material for controlled release of phenolic compounds from Andean tubers. Full article

Ulluco (Ullucus tuberosus Caldas) is an Andean tuber crop of high nutritional and genetic importance. However, its vegetative propagation promotes the accumulation of pathogens and limits the availability of uniform, high-quality planting material. In this study, an efficient and reproducible in vitro micropropagation protocol was established for an ulluco genotype from the Amazonas region of Peru. Nodal segments were cultured on MS (Murashige and Skoog) medium supplemented with 6-benzylaminopurine (BAP) or kinetin (KIN) at increasing concentrations (0.0–2.0 mg L⁻¹). For rooting, in vitro-derived shoots were transferred to MS medium supplemented with indole-3-butyric acid (IBA) or 1-naphthaleneacetic acid (NAA) at the same concentration range (0.0–2.0 mg L⁻¹). The explants exhibited a high basal morphogenetic capacity; however, the addition of cytokinins significantly enhanced the response. KIN at 2.0 mg L⁻¹ achieved 100% regeneration, whereas BAP at 0.2 mg L⁻¹ maximized shoot proliferation, producing 2.07 shoots per explant. Shoot elongation was greater with KIN at 1.0 mg L⁻¹, reaching 39.15 mm. In the rooting phase, the response varied depending on the type and concentration of auxin. NAA at 0.1 mg L⁻¹ resulted in 100% rooting and produced the greatest root length (41.93 mm), whereas IBA at 0.1 mg L⁻¹ maximized the number of roots (4.67), although roots were shorter. Rooted plantlets exhibited 100% survival after eight weeks of acclimatization. This protocol provides an effective system for the rapid production of vigorous and uniform clonal plants and represents a useful tool for the propagation, conservation, and future biotechnological improvement of ulluco. Full article

Ullucus tuberosus is an underutilized Andean tuber of South America, representing a highly nutritious food source valuable in bioactive compounds and used in traditional medicine by the local population. Despite its potential as a functional food, limited information is available regarding the phenolic composition of its diverse varieties, hindering its revalorization and potential biotechnological applications. In this study, the total phenolic content (TPC), antioxidant activity (AA), and thirteen individual phenolic compounds were investigated in five ulluco varieties using UV-Vis spectrophotometry and ultra-high-performance liquid chromatography, coupled with electrospray ionization and a triple quadrupole mass spectrometer (UHPLC-ESI-MS/MS). Statistical analyses revealed significant differences (p < 0.05) among the varieties in TPC, AA, and the concentration of the four quantified flavonoids. The major flavonoids found were rutin, quercetin-3-glucoside, kaempferol-3-rutinoside, and isorhamnetin-3-rutinoside, using solid-phase extraction (SPE-C8) as a cleanup step for ultrasound-assisted extracts, achieving satisfactory precision and recovery. Principal Component Analysis (PCA) effectively discriminated the samples based on their phenolic profiles, AA, and TPC. These findings contribute to the revalorization of ulluco varieties by providing new insights into their phenolic composition and demonstrating their potential as a source of health-promoting bioactive compounds. Full article

The cultivation of potatoes is essential for rural food security, and the use of Unmanned Aerial Vehicle Red-Green-Blue (UAV-RGB) imagery allows for precise and cost-effective estimation of yield and identification of varieties, overcoming the limitations of manual assessment. We evaluated four INIA varieties (Bicentenario, Canchán, Shulay and Tahuaqueña) by integrating agronomic measurements (height, number and weight of tubers, leaf health) with color and textural indices derived from RGB orthomosaics. Yield prediction was modeled using Random Forest (RF) and Gradient Boosting (GB); varietal identification was approached with (i) a Convolutional Neural Network (CNN) that classifies RGB images and (ii) classical models such as Random Forest, Support Vector Machines (SVMs), K-Nearest Neighbors (KNNs), Decision Trees and Logistic Regression trained on EfficientNetB0 embeddings. The results showed significant genotypic differences in yield (p < 0.001): Tahuaqueña 13.86 ± 0.27 t ha⁻¹ and Bicentenario 6.65 ± 0.27 t ha⁻¹. The number of tubers (r = 0.52) and plant height (r = 0.23) correlated with yield; RGB indices showed low correlations (r < 0.3) and high redundancy (r > 0.9). RF achieved a better fit (Coefficient of determination, R² = 0.54; Root Mean Square Error, RMSE = 2.72 t ha⁻¹), excelling in stolon development (R² = 0.66) and losing precision in maturation due to foliar senescence. In classification, the CNN and RF on embeddings achieved F1-macro ≈ 0.69 and 0.66 (Receiver Operating Characteristic—Area Under the Curve, ROC AUC RF = 0.89), with better identification of Bicentenario and Shulay. We conclude that UAV-RGB is a cost-effective alternative for phenotypic monitoring and varietal selection in high Andean contexts. These findings support the integration of UAV-RGB imagery into breeding and monitoring pipelines in resource-limited Andean systems. Full article

The transformation of Andean grains and tubers through fermentation and bioencapsulation has emerged as a key strategy to enhance their nutritional, functional, and biotechnological value, driven by advances in proteomic and metabolomic techniques. This study aimed to systematize recent evidence on the biochemical and functional modifications induced by these processes and their potential application in the development of functional foods. The methodology integrated 67 studies analyzed using tools such as R 4.5.1 with the JupyterLab interface 4.5.2, SCImago Graphica Beta 1.0.53, and VOSviewer 1.6.20, incorporating data generated through LC-MS/MS, UHPLC-QTOF, Orbitrap platforms, transcriptomics, and combined omics approaches, considering original studies published between 2020 and 2025. The main findings indicate substantial increases in free amino acids (up to 64.8%), phenolic compounds (2.9–5.2%), and antioxidant activity (up to 45%), along with the identification of 430 polyphenols, 90 flavonoids, 14 novel oxindole acetates, and bioactive peptides with IC50 values ranging from 0.51 to 0.78 mg/mL. Bioencapsulation showed controlled release of bioactive compounds, highlighting nanocapsules of 133–165 nm with a maximum release of 9.86 mg GAE/g. In conclusion, the combination of fermentation and encapsulation enhances the stability, bioavailability, and functionality of Andean crops, supporting their industrial adoption for the development of sustainable nutraceutical foods that improve health and promote the valorization of traditional resources. Full article

Postharvest losses caused by potato tuber moths severely impact storage in the Andean highlands, where reliance on synthetic insecticides poses sustainability and safety concerns. This study evaluated eco-friendly alternatives for protecting stored seed tubers of the widely adopted cultivar INIA 302 Amarilis in Cajamarca, Peru. In two storage facilities, a completely randomized block design compared four treatments: Bacillus thuringiensis plus talc (Bt-talc), talc, agricultural lime, and wood ash against an untreated control. Powders were applied at 50 g per 10 kg of tubers, and incidence, severity of damage, and live larvae were assessed over 150 days. Bt–talc consistently achieved the lowest damage. Incidence in Cochapampa was 16.8% ± 6.2 with Bt-talc, compared with 58.1% ± 3.9 in the control; in Sulluscocha, incidence was 25.5% ± 4.8 and 64.2% ± 3.0 for Bt-talc and the control, respectively. A similar pattern was observed for moth-damage severity in both localities. Live larvae per unit were also markedly lower with 1.3 ± 0.3 (Cochapampa) and 1.6 ± 0.6 (Sulluscocha) under Bt–talc. A single dusting with Bt–talc, or alternatively agricultural lime, offers effective, accessible, and sustainable control of potato tuber moths in high-Andean storage. Full article

Oca (Oxalis tuberosa Mol.) is an Andean crop with high nutritional and cultural value; however, its vegetative propagation makes it challenging to ensure a continuous supply of high-quality planting material. In this study, an efficient and reproducible in vitro propagation protocol was established for the oca genotype OT–001 (Amazonas, Peru), integrating shoot multiplication, rooting, and acclimatization. One-centimeter nodal segments were cultured in MS medium supplemented with 6-benzylaminopurine (BAP) or kinetin (KIN) at increasing concentrations ranging from 0.1 to 2.0 mg L⁻¹. For rooting, one-centimeter shoots were transferred to MS medium supplemented with indole-3-butyric acid (IBA) or 1-naphthaleneacetic acid (NAA) at increasing concentrations ranging from 0.1 to 2.0 mg L⁻¹. The variables evaluated four weeks after treatment initiation were regeneration percentage, rooting percentage, number of shoots per explant, number of roots per explant, number of nodes, and shoot length. The regeneration rate reached 100% with both BAP and KIN treatments; however, shoot proliferation was highest with 1.0 mg L⁻¹ BAP, producing an average of 7.4 shoots per explant compared to 2.3 shoots in the control. Meanwhile, KIN concentrations of 0.2–0.5 mg L⁻¹ promoted the development of longer shoots (up to 31.4 mm). In rooting, although the control achieved 93.3%, auxin supplementation improved root architecture. IBA at 0.1 mg L⁻¹ achieved 100% rooting with the longest roots (23.9 mm), while 2.0 mg L⁻¹ IBA maximized the number of roots (14.2 roots per explant). With NAA, the root systems were dense but shorter. The in vitro-regenerated plantlets exhibited 100% survival after 15 and 30 days of acclimatization in sterile agricultural soil, demonstrating the high quality of the plant material obtained. The protocol enables the production of homogeneous and vigorous plantlets throughout the year and provides a practical foundation for the ex situ conservation of oca germplasm and its commercial propagation. It also establishes the basis for advanced applications such as genetic transformation and gene editing. Full article

Postharvest losses from potato tuber moth severely constrain seed quality in Andean smallholder systems. This study evaluated four locally available repellent plants—Ambrosia peruviana, Eucalyptus globulus, Artemisia absinthium, and Minthostachys mollis—applied as dried leaves layered within seed bags of INIA 302 ‘Amarilis’ under farmer-like storage at two highland sites in Cajamarca, Peru (Huaytorco, 3350 m; Samaday, 2750 m), over 187 days. Within each site, a Completely Randomized Design with three bag-level replicates per treatment was used, and damage was assessed after 187 days as incidence of attacked tubers, internal damage severity and live larval counts. Endpoint data were analyzed separately by site using Kruskal–Wallis tests followed by Dunn’s post hoc test with Šidák correction (α = 0.05). Across both sites, all botanicals significantly reduced damage severity and live larval counts relative to the untreated control. At the warmer, lower site, A. absinthium and M. verticillata achieved large effect sizes, with severity and larval numbers reduced by roughly 80–90% compared with the control, while at the cooler, higher site, larvae were not detected in any botanical treatment. These findings indicate that simple layering of dried leaves from locally available plants, particularly wormwood and muña, can substantially mitigate S. tangolias damage in highland seed potato stores and represents a promising, low-cost complement to integrated pest management, although multi-season and dose-response studies are still needed to confirm and refine this approach. Full article

Potato (Solanum tuberosum L.) is a key staple crop in the Peruvian Andes, but its productivity is threatened by fungal pathogens such as Rhizoctonia solani and Alternaria alternata. In this study, 71 native bacterial strains (39 from phyllosphere and 32 from rhizosphere) were isolated from potato plants across five agroecological zones of Peru and characterized for their plant growth-promoting (PGPR) and antagonistic traits. Actinomycetes demonstrated broader enzymatic profiles, with 2ACPP4 and 2ACPP8 showing high proteolytic (68.4%, 63.4%), lipolytic (59.5%, 60.6%), chitinolytic (32.7%, 35.5%) and amylolytic activity (76.3%, 71.5%). Strain 5ACPP5 (Streptomyces decoyicus) produced 42.8% chitinase and solubilized both dicalcium (120.6%) and tricalcium phosphate (122.3%). The highest IAA production was recorded in Bacillus strain 2BPP8 (95.4 µg/mL), while 5ACPP6 was the highest among Actinomycetes (83.4 µg/mL). Siderophore production was highest in 5ACPP5 (412.4%) and 2ACPP4 (406.8%). In vitro antagonism assays showed that 5ACPP5 inhibited R. solani and A. alternata by 86.4% and 68.9%, respectively, while Bacillus strain BPP4 reached 51.0% inhibition against A. alternata. In greenhouse trials, strain 4BPP8 significantly increased fresh tuber weight (11.91 g), while 5ACPP5 enhanced root biomass and reduced stem canker severity. Molecular identification confirmed BPP4 as Bacillus halotolerans and 5ACPP5 as Streptomyces decoyicus. These strains represent promising candidates for the development of bioinoculants for sustainable potato cultivation in Andean systems. Full article

Mashua (Tropaeolum tuberosum), an underutilized Andean tuber, has gained increasing scientific interest due to its exceptional nutritional composition and high bioactive phytochemical content. This narrative review synthesizes evidence from 68 peer-reviewed studies published up to August 2025, obtained through searches in Scopus and Web of Science, examining its macro- and micronutrient profile, richness in starch, proteins, and vitamin C, and diverse bioactive compounds, including glucosinolates, anthocyanins, and flavonoids. These metabolites exhibit strong antioxidant, anti-inflammatory, anticancer, and cardioprotective activities, with the highest concentrations being observed in purple and black morphotypes. Recent studies demonstrated that incorporating mashua into bakery, extruded, and fermented food formulations enhanced nutritional value and oxidative stability. Overall, mashua represents a promising natural ingredient for functional foods and nutritional applications. Further research is required to optimize processing conditions, improve the stability and bioavailability of its active compounds, and validate its health-promoting effects. Full article

Potato (Solanum tuberosum L.) is the third most important food crop worldwide and a cornerstone of food security across the Andean region. However, its production is increasingly threatened by the potato psyllid Bactericera cockerelli (Šulc), the vector of Candidatus Liberibacter solanacearum, the causal agent of the purple-top complex associated with zebra chip disease, which severely reduces both tuber yield and quality. This study was conducted from September 2024 to February 2025 in the province of Huancabamba, Peru, to evaluate the efficacy of biological and chemical control agents against B. cockerelli under field conditions. A randomized complete block design was implemented with five treatments and four replicates, totaling 20 experimental units, each consisting of 20 potato plants (S. tuberosum L.), of which 10 plants were evaluated. Treatments included an untreated control (T0), a chemical control (thiamethoxam + lambda-cyhalothrin, abamectin, and imidacloprid) (T1), and three biological control agents: Beauveria bassiana CCB LE-265 (>1.5 × 10¹⁰ conidia g⁻¹) (T2), Paecilomyces lilacinus strain 251 (1.0 × 10¹⁰ conidia g⁻¹) (T3), and Metarhizium anisopliae (1.0 × 10¹⁰ conidia g⁻¹) (T4). Foliar applications targeted eggs, nymphs, and adults of the psyllid. Results indicated that B. cockerelli mortality across developmental stages was lower under biological treatments compared with T1, which achieved the lowest probability of purple-top symptom expression (46%) and a zebra chip incidence of 60.60%. Among the biological agents, M. anisopliae (T4) reduced incidence to 56.60%, while P. lilacinus (T3) demonstrated consistent suppression of nymphal populations. In terms of yield, T1 achieved the highest tuber weight (198.86 g plant⁻¹) and number of tubers (7.74 plant⁻¹), followed by T3 (5.08) and T4 (4.24). Nevertheless, all treatments exhibited low yields and small tuber sizes, likely due to unfavorable environmental conditions and the presence of the invasive pest. Overall, chemical control was more effective than biological agents; however, the latter showed considerable potential for integration into sustainable pest management programs. Importantly, vector suppression alone does not guarantee the absence of purple-top complex symptoms or zebra chip disease in potato tubers. Full article

Mashua (Tropaeolum tuberosum), a resilient and underutilized Andean tuber, is a high-potential nutritional and functional food innovation resource. This review surveys information on the nutritional composition, bioactive profile, and functional properties of the tuber based on a comprehensive literature search conducted in the Scopus database. The search strategy employed eight Boolean operators combining the following terms: (“Tropaeolum tuberosum” OR “mashua”) AND (“bioactive compounds” OR “functional properties” OR “glucosinolates” OR “antioxidant activity” OR “food processing”). The review included English-language research articles published between 2000 and 2025. Its diverse constituents, such as glucosinolates, phenolics, and anthocyanins, have antioxidant, anti-inflammatory, and antimicrobial activities. Technologies such as freeze-drying, microencapsulation, and 3D printing make it easier to preserve these bioactive components and ensure their use in novel food products. Although Mashua has potential, its widespread adoption remains limited by its distinct sensory characteristics and the lack of clinical validation regarding its effect on human health. To extract the full potential of mashua as a functional ingredient for the global food industry, consensus evidence exists around the need for standardized analytical methodologies, technological innovation, and sustainable value chain development. Full article

Potato production in the Andean highlands demands strategies that reduce dependence on synthetic inputs without sacrificing yield. We evaluated two microbial bioinputs—Bacillus subtilis and Trichoderma viride—applied once pre-plant to seed tubers, under three organo-mineral fertilization regimes (0%, 50%, and 100% of the recommended NPK rate) in two cultivars (INIA 303-Canchán and Yungay) in field conditions in Ayacucho, Peru, using a randomized complete block, split-plot design (three replicates). Agronomic traits (plant height, root dry weight, stems per plant, tubers per plant, and plot-level yield) were analyzed with robust two-way ANOVA and multivariate methods. Combining microbial inoculation with 50% NPK sustained growth responses comparable to 100% NPK for key traits: in Yungay with T. viride, plant height at 50% NPK (≈96.15 ± 1.71 cm) was not different from 100% NPK (≈98.87 ± 1.70 cm), and root dry weight at 50% NPK (≈28.50 ± 0.28 g) matched or exceeded 100% NPK (≈16.97–22.62 g depending on cultivar–treatment). Notably, T. viride increased root biomass even without mineral fertilizer (≈27.62 ± 0.29 g in Yungay), while B. subtilis enhanced canopy vigor and stem number at full NPK (≈4.5 ± 0.29 stems). Yungay out-yielded INIA 303-Canchán overall (≈57.5 ± 2.5 kg vs. ≈42.7 ± 2.5 kg per plot). The highest yields occurred with B. subtilis + 100% NPK (≈62.88 ± 6.07 kg per plot), followed by B. subtilis + 50% NPK (≈51.7 ± 6.07 kg per plot). Plant height was the strongest correlate of yield (Spearman ρ ≈ 0.60), underscoring its value as a proxy for productivity. Overall, a single pre-plant inoculation with B. subtilis or T. viride can halve mineral fertilizer inputs while maintaining growth and sustaining high, cultivar-dependent yields in highland potato systems. Full article

Tropaeolum tuberosum (mashua) is a native Andean tuber recognized for its high nutritional and bioactive compound content. Among the various morphotypes, the black and yellow variants show potential differences in composition and functionality. This study aimed to compare the thermo-energetic, nutritional, and physicochemical characteristics of two morphotypes (black and yellow) of Tropaeolum tuberosum flour from the Peruvian Andes. Flours were obtained from tubers harvested in Ayacucho, Peru, and analyzed using elemental analysis for carbon, hydrogen, nitrogen, and sulfur (CHNS), inductively coupled plasma optical emission spectrometry (ICP-OES), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and bomb calorimetry. The empirical formula is CH_1.74O_0.91N_0.06S_0.005 for black mashua and CH_1.78O_0.92N_0.05S_0.005 for yellow mashua. Black flour exhibited higher protein (17.6% vs. 14.8%) and fat contents (8.0% vs. 6.7%), along with nearly double the iron content. Both flours showed similar starch granule morphology and gelatinization enthalpy (~2 J/g), but the black flour had higher gelatinization temperatures. Calorimetric analysis revealed a greater net calorific value (qNCV) in black mashua flour (4157 ± 22 kcal/kg) than in yellow flour (4022 ± 19 kcal/kg). The thermogravimetric profiles indicated good thermal stability with approximately 30% residual mass. These findings suggested that black mashua flour possesses superior nutritional and energy characteristics, supporting its application in functional food formulations and energy-rich gluten-free products. Full article