Vegetables and fruits are excellent sources of vitamins, minerals, and phytochemicals, which are known for immune-strengthening properties that resist diseases (Zhen et al., 2016). Spices are aromatic vegetables in the form of the roots, tubers, seeds, or leaves (Oyewale et al., 2020). They are usually added to improve the palatability of foods. However, some vegetables and spices are extracted for juice preparation to produce refreshing drinks while extracts of some, singly or in combinations, are sometimes employed in traditional medicine practices (Mensah et al., 2008; Zhen et al., 2016).
One important vegetable which is reported to be potent in naturally occurring antioxidants and antiviral compounds is Hibiscus sabdariffa (Roselle, ‘Isapa’) locally known as zoborodo in the northern parts of Nigeria (Yadeng et al., 2015). The green leaves of this plant are employed in soup preparation among the Yoruba tribe of Nigeria, while the dried calyces of the red cultivars are used in the preparation of a refreshing drink popularly referred to as Zobo or ‘Soborodo’ which originated from the northern parts of Nigeria (Aworh, 2014). There exists credible documentation on the presence of a high level of polyphenolic compounds and anthocyanins with notable anti-oxidative, anti-viral, anti-hypertensive, and anti-inflammatory effects in the leaf and calyx extracts of Hibiscus sabdariffa (Umaru et al., 2007; Chen et al., 2013; Zhen et al., 2016).
Spices are also rich sources of phytochemicals (polyphenols) that are active natural immune-balancing compounds (Mensah et al., 2008). Phenolic acids like gallic acids and flavonoids occur naturally in plant food materials like spices (Oyewale et al., 2020). Vegetables, spices, herbs, and natural flavouring agents owe their antioxidant and immune balancing potentials to these embedded bioactive compounds (Aworh, 2014; Zhen et al., 2016). When foods or drinks rich in these agents are consumed in sufficient quantities, the immunity of the body will be balanced/boosted to fight against infections, probably as recently witnessed by the Coronavirus (COVID-19) pandemic.
Our research team recently worked on Zobo drink flavoured with natural/local spices: ginger (Zingiber officinale), alligator pepper (Aframomum danielli; ‘atare’), and cloves (Caryophllus aromaticus; ‘kanafuru’). The findings showed that their mineral contents: magnesium, potassium, sodium, iron, and zinc, (potential immunity-boosting agents) were adequate and higher than the Zobo drink flavoured with commercial strawberry essence. Also, potassium was found to be the most abundant mineral element in all the samples but with higher amounts in Zobo drinks made with spices. Potassium is important in maintaining a balanced body fluid to prevent cases of hypertension (Otolowo et al., 2018); this confirmed the anti-hypertensive potential of the spiced Zobo drink. The antioxidant capacities of spiced Zobo drinks in terms of vitamins C and A contents were moderately adequate.
The remarkable content of vitamins and high phenolic contents of Zobo calyces and spices used in the preparation are responsible for the antioxidant property of the Zobo drinks. The antioxidant properties demonstrated by the drink suggest its potential in combating free radical-mediated and immune-related diseases as antioxidants are reported as agents that prevent or halt (where it has been initiated) the production of free radicals in the human cells (Juliani et al., 2009). As revealed by our study, the prominent antioxidant effect of Zobo drink was due to its vitamins, minerals, tannins, and phytates (phenolic compounds) contents. Consequently, phytoconstituents that are present in the spices in addition to its naturally occurring anthocyanins may have contributed to the overall health-claim benefits of Zobo drinks.
TThus, pleasurable and regular consumption of spiced Zobo drinks will provide the body with strong immunity against infections and diseases. In this era of the COVID-19 pandemic, the effect of the infection can easily be managed by the strengthened immunity of the body. This is not unconnected with the fact that most of the COVID-19 pandemic death toll in Nigeria falls within the categories of people said to have been with underlining sicknesses and the associated impaired immunity (PTF Brief on COVID-19, Nigeria). We, therefore, advocate that people find naturally refreshing Zobo drinks made with spices as good replacements for the commonly hawked around Zobo drinks that are stuffed only with sweeteners that have no health benefits. Hygienically prepared spiced Zobo drink in presentable packaging can be served in social gatherings as this will also discourage the use of the usual carbonated or alcoholic drinks. In so doing, a strong and balanced immune system will be built to guide against infections and diseases like COVID-19.
As a way to take the ‘gown’ to the ‘town’, Wesley University Ondo, headed by an erudite, dynamic and quintessential academic and leader par excellence, the Vice-Chancellor, Prof. Sunday Ndubueze Ukachukwu is passionate about contributing her own quota in using research findings to solve emerging societal challenges. Nevertheless, in the light of the present Coronavirus pandemic, the advisories by the Nigeria Centre for Disease and Control (NCDC) and other appropriate health authorities should strictly be adhered to. Stay Safe!! Stay Healthy!!!
A Research team of the Department of Food Science and Technology, Wesley University Ondo; led by Dr. Dupe Temilade Otolowo.