Characterization of Anthocyanins in Sweet Potato Leaves Grown in Various Stages and Conditions

Phytochemical-enriched edible greens, sweet potato leaves (Ipomoea batatas L.), have become popular due to potential health benefits. However, the phytochemical contents in sweet potato leaves and their subsequent change over harvest stages and growth condition are mostly unknown. In this study, the anthocyanin profile and content in leaves of four sweet potato cultivars, i.e., white-skinned and white-fleshed Bonita, red-skinned and orange-fleshed Beauregard, red-skinned and white-fleshed Murasaki and purple-skinned and purple-fleshed P40, were evaluated. Fourteen anthocyanins were isolated and identified by HPLC-MSI/MS. The most abundant was cyanidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside, which comprised up to 20% of the total anthocyanins. Of the young leaves (1st and 2nd slip cuttings), Bonita contained the highest anthocyanin content followed by P40. Of the mature leaves (vine stage), Beauregard had the greatest anthocyanin (592.5 ± 86.4 mg/kg DW) and total phenolic (52.2 ± 3 mg GAE/g DW). It should be noted that the lowest anthocyanin and total phenolic content of shoots were found in P40, while tubers of P40 contain the highest content of each. Furthermore, the increase in leaf anthocyanin content over the growth stages that was observed in three of the cultivars but not in P40. No significant difference of anthocyanin content was found in Beauregard leaves grown in the high tunnels when compared with that in the open field. This study demonstrated for the first time that anthocyanin levels were significantly changed in response to various growth stages but not high tunnel condition, indicating that the effect of anthocyanin biosynthesis in sweet potato leaves is highly variable and genotype specific.

Optimization of Water Cooking of Sweet Potato (Ipomea batatas) Leaves and Characterization of Three Nutritional Interest Molecules (Folic Acid, Iron and Phytate)

Sweet potato (Ipomea batatas) leaves are among the leafy vegetables most consumed by Ivorian population. In order to preserve iron and folic acid, and to eliminate phytates, a study of optimization of water cooking of these leaves was conducted. Response surface methodology was employed to describe the effects of cooking time and leaf quantity on iron, folic acid and phytate contents of sweet potato leaves using a central composite design. Response surfaces and isoresponse curves were plotted to visualize areas of interest (optimal points). Results showed that the experimental data were adequately fitted into the second-order polynomial model. Cooking time had significant effects (P < .05) on folic acid and phytate contents. The effect of leaf quantity was significant (P < .01) on the three response variables. In addition, the optimal points were located in areas of the experimental domain where iron and folic acid contents were high. Therefore, three optimal conditions for water cooking (cooking time, leaf quantity) were identified: (10 min, 400 g), (7.93 min, 300 g) and (22.07 min, 441.4 g). Under these conditions, iron and folic acid contents (mg/100 g) were: (49.17, 12.58), (37.00, 16.27) and (48.77, 11.26), respectively. These results could be exploited to formulate iron and folic acid supplementation products from sweet potato leaves.

Ornamental potential of sweet potato accessions / Potencial ornamental de acessos de batata-doce

Sweet potato [Ipomoea batatas (L.) Lam.] is a multipurpose plant due to the different uses for its roots, leaves, and branches. The objective of this study was to evaluate the ornamental potential of sweet potato accessions from the Germplasm Bank of Embrapa Hortaliças, Brasilia, DF, Brazil. The morphological characterization and evaluation of the ornamental potential used five accessions with distinct leaf shape (CNPH 980, CNPH 1205, CNPH 895, CNPH 796, CNPH 1284) and 12 qualitative and quantitative descriptors [plant type (PT), leaf lobe type (LLT), immature leaf color (ILC), leaf lobe number (LLN), branch color (BC), shape of central leaf lobe (SCLL), petiole pigmentation (PP), mature leaf size (MLS), mature leaf color (MLC), leaf shape (LS), branch yield (BY), and root yield (RY)]. In the evaluation of the ornamental potential, each criterion was scored from 10 (minimum) to 100 (maximum). Leaf lobe number was the trait that pleased the evaluators the most, and the greater the number of lobes, the greater was the ornamental potential. CNPH 980, CNPH 1205, and CNPH 1284 stood out for this trait. CNPH 1284 (almost divided leaf type) had the greatest score and was considered, by the evaluators, as the accession with the most harmonious aesthetics, indicating a great ornamental potential for the consumer market. All accessions studied presented considerable ornamental potential and could be used in floral arrangements or garden beds.

A batata-doce [Ipomoea batatas (L.) Lam.] é uma planta com diferentes aptidões de uso das suas raízes, folhas e hastes. O objetivo deste trabalho foi avaliar o potencial ornamental de acessos de batata-doce oriundas do banco de germoplasma mantidos na Embrapa Hortaliças, Brasília, DF, Brasil. Para a caracterização morfológica e avaliação do potencial ornamental, foram escolhidos cinco acessos com formatos de folhas diferentes (CNPH 980, CNPH 1205, CNPH 895, CNPH 796, CNPH 1284) e utilizados doze descritores qualitativos e quantitativos [tipo de planta (TP), tipo de lóbulo da folha (TLF), cor da folha imatura (CFI), número de lóbulos por folha (NLF), cor das ramas (CR), formato do lóbulo central (FLC), pigmento no pecíolo (PP), tamanho da folha madura (TFM), cor da folha madura (CFM), formato da folha (FF), produção de ramas (BY) e produção de raízes (RY)]. Na avaliação do potencial ornamental, cada critério foi pontuado por meio de notas variando de 10 (mínimo) a 100 (máximo). A característica número de lóbulos da folha foi a que mais agradou os avaliadores. Observou-se que quanto mais lóbulos, maior o potencial ornamental, sendo que os acessos CNPH 980, CNPH 1205 e CNPH 1284 se destacaram para essa característica. CNPH 1284, com folhas no formato quase dividido, obteve a maior nota e foi considerado como o acesso com a estética mais harmoniosa, indicando grande potencial ornamental para o mercado consumidor, na opinião dos avaliadores. Os cinco acessos estudados apresentaram considerável potencial ornamental, podendo ser usados como forragem, complementos para arranjos florais ou como jardineiras.