Influence of agro-ecological production areas on antioxidant activity, reducing sugar content, and selected phytonutrients of orange-fleshed sweet potato cultivars

Abstract

Sweet potato is an important staple, and it is mainly known for its contribution of β-carotene in human diet. The effects of cultivar and habitat on this pigment and other nutritional characteristics of the crop still require investigation. In this study, three locally bred cultivars of sweet potato, two of which are orange-fleshed, were grown in three different agro-ecological areas to determine soluble sugar content, β-carotene, and total antioxidants of roots. In addition antioxidant activity, total carotenoids, and chlorophyll content were determined in edible leaves. Reducing sugars, β-carotene, total antioxidants capacity, total carotenoids, and chlorophyll content were significantly affected by environmental conditions. The location at lower altitude and closer to the coastline showed high evapotranspiration, thus reducing sugar content, antioxidant activity, and phytonutrients in both storage roots and leaves. Absence of water stress in agro-ecological locations further inland and at higher altitudes was associated with an increase in these compounds. Free radical scavenging activity of DPPH was higher in the storage roots (610.49 µmoles TE/100g) than in the leaves (426.06 µmoles TE/100g); nevertheless, opposite results were found for the ferric ion reducing activity (FRAP). The deep orange-fleshed cultivar A45 contained high β-carotene (15 mg/100g), which is enough to meet RDA for vitamin A. There is evidence of agro-ecological effect on sweet potato nutritional value.

Characterization of Rosa canina Fruits Collected in Urban Areas of Slovakia. Genome Size, iPBS Profiles and Antioxidant and Antimicrobial Activities

“…The contents of polyphenols and the antioxidant activity can be influenced by agro-ecological conditions, including locality, humidity, soil composition, water deficit, and temperature. Motsa et al [36] found that the contents of secondary metabolites, especially of polyphenols, can increase under drought conditions because of the increased oxidative stress perceived. Similarly, Oh et al [37] revealed that drought stress and high temperatures can lead to increased amount of bioactive compounds which may serve as the main defense mechanism.…”

Sifat Fisik dan Kimia Ubijalar pada Berbagai Pemupukan N di Lahan Pasang Surut Kalimantan Selatan

“…Faktor lingkungan, yakni radiasi sinar matahari diperlukan dalam sintesis karotenoid (karotenogenesis) karena kemampuannya untuk menyerap cahaya. Selain itu, pupuk K, jenis tanah, ketinggian tempat, suhu, ketersediaan air, musim, umur panen, dan ukuran umbi juga berpengaruh terhadap warna dan kadar beta karoten ubi jalar (Liu et al 2009;Ukom et al 2009;Abd El-baky et al 2010;Ukom et al 2011;Laurie et al 2012;Faber et al 2013;Motsa et al 2015;Kathabwalika et al 2016). pemberian pupuk rekomendasi urea, TSP, dan KCl masing-masing 100 kg/ha (Ginting et al 2013).…”

“…pemberian pupuk rekomendasi urea, TSP, dan KCl masing-masing 100 kg/ha (Ginting et al 2013). Pada kondisi lingkungan tumbuh yang kurang optimal, sisntesis metabolit sekunder, termasuk beta karoten, biasanya meningkat sebagai mekanisme pertahanan diri tanaman (Jaleel et al 2009;Wang dan Frei 2011;Motsa et al 2015). Namun hasil penelitian ini perlu dikonfirmasi lagi pada lokasi yang sama melihat besarnya variasi kadar beta karoten umbi (Tabel 2) dan relatif kecilnya ukuran umbi untuk memastikan pengaruh perlakuan pemupukan N terhadap kadar beta karoten ubi jalar di lahan pasang surut.…”

“…Varietas Beta 3 memiliki kadar gula reduksi 4,72% bk, sedangkan varietas lokal hanya 2,56% bk. Kadar gula reduksi dilaporkan meningkat jika ubi jalar ditanam pada lokasi dengan ketinggian tempat dan ketersediaan air rendah (Motsa et al 2015).…”

The Pruning Effect on the Storage Root Yield and Starch Content of Sweet Potato Clones Planted at Dry Land

“…Sweet potatoes are food crops with wide ecological adaptability, drought-tolerant, often cultivated in the marginal soils under low agricultural input and are able to grow with limited water available for irrigation (Motsa et al, 2015a;Motsa et al, 2015b;Chipungu et al, 2018;Lestari et al, 2019). Sweet potato plantations can reduce soil erosion because of its vines' ability to cover the soil surface (Oshunsanya, 2016).…”