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This work demonstrates how priming durations affect high-and low-vigor sunflower (Helianthus annuus L.) seeds and relate to the dynamics of enzymatic and nonenzymatic antioxidant systems against heat stress. Heat tolerance of high-vigor seeds were enhanced when primed 3-6 h, and low-vigor seeds were enhanced when primed 3-12 h. Priming at optimum duration led to increases in ascorbate peroxidase (APX) activity and higher levels of total phenolic content (TPC), vitamin C and total chlorophyll combined with decreased H 2 O 2 content. After exposure to heat stress, the primed seeds maintained reactive oxygen species (ROS) levels and alleviated seeds damage. This may be due to protective mechanisms of priming that prevented severe loss in catalase (CAT) and APX activities, maintained superoxide dismutase (SOD) activity, and increased TPC, proline, vitamin C, and carotenoid accumulation. However, extending priming to 18 h with subsequent heat stress decreased germination percentage. Control seeds lost viability, as oxidative balance was not maintained due to heat stress. These results support the participation of nonenzymatic antioxidants in the improved tolerance to heat stress of primed seeds.

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In the Philippines, indigenous vegetables like ‘alugbati’ (Basella alba L.) can be utilized to address micronutrient deficiencies, such as vitamin A deficiency (VAD). This study aimed to develop fresh egg noodles with higher vitamin A content through the utilization of ‘alugbati’ leaves powder. Powder from ‘alugbati’ leaves was produced through dehydration of fully expanded leaves. The resultant powder was used to create three formulations of fresh egg noodles at 10%, 15%, and 20% substitution levels, with 100% wheat flour serving as the control. All formulations and the control were subjected to a water disintegration test and preference ranking test. The most preferred formulation was further evaluated for proximate composition, total carotenoid content (TCC), color, physical characteristics, and consumer acceptability. Data from triplicate experiments were statistically analyzed (p ≤ 0.05). Results showed that all samples were resistant to water disintegration (20 min in boiling water) and egg noodle with 15% substitution level was the most preferred. This sample had significantly higher ash (2.27 ± 0.28), fiber (1.77 ± 0.38), and protein (11.50 ± 0.11) contents than the control. A significantly higher TCC (1550 µg/g) compared to the control (610 µg/g) also signified that substituting with ‘alugbati’ leaves powder increased the vitamin A content of the noodles. From this, consuming 5–10 g of ‘alugbati’ egg noodles will be able to provide the vitamin A requirement of 400–800 µg retinol equivalent (RE). The egg noodles with a 15% substitution level also had a significantly darker green color and significantly lower elasticity. Moreover, this formulation was generally acceptable with mean Hedonic scores ranging from 7.20 (Like Moderately) to 7.80 (Like Very Much). This study demonstrated that fresh egg noodles with ‘alugbati’ leaves powder can be a good source of vitamin A. Clinical studies should be conducted to determine the role of the product in alleviating VAD especially in children and pregnant women.

High temperature is a limiting factor in the seed germination of most crops. This study evaluated the effects of hydropriming at 6, 12 and 18 h on germination performance and seedling establishment of sunflower seeds under high air temperature. Results showed that germination of unprimed seeds was suppressed at an average elevated temperature of 44.3 °C (range of 39.3 °C to 53.3 °C) for eighteen days indicated by an increased lag time to onset of germination and decreased germination percentage. Conversely, priming seeds for 12 h to 18 h increased the germination percentage, time to 50% seedling emergence (T₅₀), germination index and vigour index. Seedlings emerging from primed seeds exhibited uniform 16-day old seedlings (18 days after sowing), leading to greater seedling dry weight and shoot length as compared to unprimed seeds. Conversely, the total chlorophyll content remain unchanged for all seeds. The significant increase in the shoot parameters suggested a positive association with priming and stress tolerance. The priming duration of 12 h to 18 h showed improvement at elevated air temperature through the reduction of ungerminated seeds and increase in seedling growth characteristics.