Comparative analysis of bioactive components across basil varieties

Abstract

Background: In every civilized nation, the stewardship of edible, aromatic, and medicinal plants holds a moral imperative for preservation and sustainable utilization. In Armenia, the rich gene pool of aromatic plants stands as a national treasure, deeply ingrained in the traditional Armenian diet. Among these, basil (Ocimum basilicum L.) emerges as a revered herb, steeped in ancient usage and renowned for its remarkable nutritional profile. With its abundant array of nutrients, basil earns its moniker as a 'sacred plant' in various cultures. Bursting with microelements, organic acids, vitamins, proteins, carbohydrates, sugars, and essential oils, basil serves as a vital source of essential components crucial for maintaining human health. Its antioxidant prowess renders it capable of combating hazardous chemicals and carcinogens, safeguarding the body against serious ailments. Additionally, basil boasts a wealth of vitamin C, beta-carotene, and polyphenols, further enhancing its therapeutic value.

Objectives: To study the bioactive components and antioxidant properties of basil varieties with distinct tastes and aromas, cultivated under Ararat Valley conditions.

Methods: Dry matter content was determined using a refractometer, while raw protein content was analyzed via the Kjeldahl method. Total sugars, vitamin C, and carotene were quantified using a spectrometric method employing the Cary 60 UV-Vis. Essential oils were assessed using Ginsberg method. Throughout the vegetation period, the duration of phenological stages, bio-morphological indicators, and yield were investigated. The experiments were conducted with four repetitions, following accepted protocols for crop studies. Each experimental plot measured 10 m². Isolation nets were used to avoid cross-pollination between varieties. Statistical analysis was performed using the ANOVA method.

Results: The 'Vkus korici' and 'Kitroni burmunq' cultivars exhibited early ripening, while the 'Karamelni', 'Rozi', and 'Manushakaguin teghakan' cultivars showed medium maturity, and the 'Kanach burmunq' variety demonstrated late ripening. This characteristic is crucial for selecting suitable basil varieties based on agricultural zones and cultivation objectives. Yield indicators among the studied varieties ranged from 0.6 to 2.0 kg/m², with the 'Manushakaguin teghakan' variety showcasing the highest yield (2.0 kg/m²), which was 3.3 times greater than that of the 'Kitroni burmunq' variety with the lowest yield. Additionally, the 'Manushakaguin teghakan' variety exhibited a relatively larger above-ground plant mass. 'Karamelni' and 'Kitroni burmunq' varieties were distinguished by their dry matter content, measuring 10.8% and 10.3%, respectively. Conversely, the 'Manushakaguin teghakan' variety had the least amount of dry matter. However, it is worth mentioning that the difference is not significant. The crude protein content among the studied varieties ranged from 14.7% to 16.2%, with the 'Kitroni burmunq' variety boasting the highest amount and the 'Kanach burmunq' variety presenting the lowest. Similar to the content of dry matter, the difference is minor. Notably, the 'Manushakaguin teghakan' and 'Vkus korici' varieties exhibited high levels of vitamin C and beta-carotene content (4.5 mg/100 g and 145 mg/kg for 'Manushakaguin teghakan', and 4.2 mg/100 g and 144.5 mg/kg for 'Vkus korici'), which are correlated with antioxidant properties. Additionally, the 'Manushakaguin teghakan' and 'Kitroni burmunq' varieties were distinguished by their total essential oil content, measuring 0.75% and 0.74%, respectively.

Conclusion: Basil, as a unique spice crop, offers considerable potential for functional food applications owing to its antioxidant properties. Therefore, selecting the appropriate variety considering functional attributes, yield, and maturity period is paramount. Among the six basil varieties studied, the 'Manushakaguin teghakan' and 'Vkus korici' varieties displayed high levels of vitamin C and beta-carotene, what determines antioxidant activity. Notably, 'Vkus korici' and 'Kitroni burmunq' showcased early maturity in the conditions of the Ararat Valley of Armenia, while 'Karamelni', 'Rozi', and 'Manushakaguin teghakan' exhibited medium maturity, and the 'Kanach burmunq' variety demonstrated late maturity. These findings suggest the potential incorporation of all basil varieties into functional foods. Among the investigated varieties, the 'Manushakaguin teghakan' is of highest interest and potential, offering not only superior nutritional and functional benefits but also economic viability attributed to its high yield and quality.

Keywords:  aromatic plant, vitamin C, beta-carotene, productivity, dry matters