Nutritional value of leafy vegetables of sub-Saharan Africa and their potential contribution to human health: A review

A comprehensive approach to the monitoring of steroidal glycoalkaloids in foods of plant origin

Steroidal glycoalkaloids (GAs) are toxins produced by solanaceous plants. As there are no fully standardized methods for their extraction and determination in food, the research aimed to: (1) develop and critically compare methods based on gas (GC) and liquid (LC) chromatography, including their coupling with mass spectrometry, and (2) to develop and optimize a universal GA extraction method. Hyphenated techniques proved to be the most useful in GA analysis: LC-MS was the most sensitive one, while GC-MS offered the highest chromatographic resolution. It was proven that quantitative results obtained using different analytical techniques cannot be directly compared. New extraction method that is more efficient than the AOAC method (997.13) was then designed and optimized. It was characterized by higher absolute recovery (99% and 34%, respectively) and allowed to extract much more GAs from the same material (e.g. 21.2 ± 1.4 and 11.82 ± 0.97 mg g-1 of potato tubers, respectively).

Heavy metals and potential health risk assessment of Lactuca sativa and Daucus carrota from soil treated with organic manures and chemical fertilizer

The large-scale production of food crops with heavy application of chemical fertilizers in the effort to meet the astronomical increase in food demands may be counterproductive to the goal of food security. This study investigated the effect of different soil treatments on the levels of heavy metals (Cr, Cu, Fe, Ni, Pb, and Zn) in two types of vegetables Lactuca sativa (lettuce) and Daucus carrota (carrot). The potential carcinogenic and non-carcinogenic health risks from their consumption were also evaluated. Planting experiment was set up in a randomized block design, with different soil treatments of soil + cow dung (CD), soil + sewage sludge (SS), soil + chemical fertilizer (nitrogen-phosphorus-potassium (NPK)), and untreated soil (UNTRD). The vegetables were harvested at maturity, washed with distilled water, and subjected to an acid digestion process before the levels of heavy metals were measured by inductively coupled plasma spectrometry (ICP-MS). The mean concentrations of the metals in the vegetables across all treatments were below the maximum permissible limits. The pattern of heavy metal accumulation by the vegetables suggested that the lettuce from SS treatment accumulated higher concentrations of heavy metals like Cr (0.20 mg/kg), Cu (3.91 mg/kg), Ni (0.33 mg/kg), and Zn (20.44 mg/kg) than carrot, with highest concentrations of Fe (90.89 mg/kg) and Pb (0.16 mg/kg) recorded in lettuce from NPK treatment. The bioaccumulation factor (BAF) showed that lettuce, a leafy vegetable, has bioaccumulated more heavy metals than carrot, a root vegetable. The BAF was generally below the threshold value of 1 in both vegetables, except in lettuce from NPK and CD treatments and carrot from NPK treatments, with BAF values of 1.6, 1.69, and 1.39, respectively. The cancer risk assessment factors were well below the unacceptable maximum range of 10-4 suggesting that consuming these vegetables might not expose an individual to potential risk of cancer development. The hazard quotient estimations were below the threshold values of 1 for all heavy metals; however, the hazard index (HI) values of 1.27 and 1.58 for lettuce from NPK and SS treatments indicate a potential non-carcinogenic health risk to consumers from intake of all the heavy metals.

Indigenous knowledge and nutritional and morphological characterization of okra (Abelmoschus esculentus (L.) Moecnh) varieties in Western Ethiopia

Okra (Abelmoschus esculentus (L.) Moecnh) is a versatile crop that is widely grown in western Ethiopia, despite that it is less researched. This study, therefore, investigates the traditional knowledge, nutritional, and morphological characteristics of two commonly grown okra varieties (Kenketse and Sharma) in west Ethiopia. A semi-structured questionnaire, checklist, and observations were used to collect primary data from households, key informants, and farms. In addition, proximate composition parameters like moisture content, total ash, crude fat, crude protein, crude fiber, utilizable carbohydrates, and gross energy fruits were measured through laboratory analysis. Fruit morphological traits, including fruit dimensions such as length and width, were determined using a digital Vernier caliper. For data analysis, SPSS software was used. The results revealed that the entire plant is used for both food and ethnomedicinal purposes. Curing ailments such as stomach pain, constipation, wound/cut, heart discomfort, back pain, malaria, diarrhea, and amoebae were among the medical benefits of okra. The proximate composition (%) on a dry matter basis of okra fruits differed significantly (p < .05) by cultivar type and drying method. Moisture (3.69%-5.24%), total ash (6.60%-8.01%), crude fat (4.87%-8.58%), crude protein (4.06%-5.23%), crude fiber (12.85%-15.26%), utilizable carbohydrate (56.42%-67.63%), and gross energy contents (326-341 kcal) were the ranges of the various proximate and energy levels. Morphological characteristics of fruit and leaf length, width, and length-to-width ratio varied with cultivar type, where Sharma had more than double the length of Kenketse (70.1 vs. 187.1 mm). Despite being an undervalued native vegetable crop in Ethiopia, the study's findings show that okra is a multipurpose vegetable for promoting human health and ensuring food and nutritional security. Therefore, stepping up its production, marketing, and consumption could help alleviate the food shortage and improve human nutrition and health in the study areas.

A Review on Bioactive Compounds, Ethnomedicinal Importance and Pharmacological Activities of Talinum triangulare (Jacq.) Willd

Talinum triangulare (Jacq.) Willd. is a traditional leafy vegetable used by tribal communities for ethnomedicinal and ethnoculinary preparations. This article reviews the current knowledge of its multiple uses, including pharmacological activities and nutritional composition. The literature survey shows that it has been traditionally useful in the treatment of several diseases, such as anaemia, diabetes, measles, and ulcers and the preparation of various traditional foods. Analysis of the literature on its phytochemicals shows its richness in bioactive compounds. Further, research also shows that this plant has antidiabetic, antiobesity, antitumor, antiulcer, hepatoprotective, and neuroprotective activities besides anti-inflammatory and antioxidant properties. Nutrient analysis of the plant reveals the presence of Ca, Zn, Fe, vitamins C and E, dietary fibre and protein in considerable quantities. The results of the pharmacological studies on the antidiabetic, antiulcer and anti-anaemic activities provide support in favour of its ethnomedicinal uses. The presence of bioactive compounds and pharmacological activities show the usefulness of this plant as a functional food.

Underutilized green leafy vegetables: frontier in fortified food development and nutrition

From the ancient period, Green leafy vegetables (GLV) are part of the daily diet and were believed to have several health beneficial properties. Later it has been proved that GLV has outstanding nutritional value and can be used for medicinal benefits. GLV is particularly rich in minerals like iron, calcium, and zinc. These are also rich in vitamins like beta carotene, vitamin E, K, B and vitamin C. In addition, some anti-nutritional elements in GLV can be reduced if it is grown properly and processed properly before consumption. Tropical countries have a wide variety of these green plants such as Red Spinach, Amaranth, Malabar Spinach, Taro Leaf, Fenugreek leaf, Bengal Gram Leaves, Radish Leaves, Mustard Leaves, and many more. This review focuses on listing this wide range of GLVs (in total 54 underutilized GLVs) and their compositions in a comparative manner. GLV also possesses medicinal activities due to its rich bioactive and nutritional potential. Different processing techniques may alter the nutritional and bioactive potential of the GLVs significantly. The GLVs have been considered a food fortification agent, though not explored widely. All of these findings suggest that increasing GLV consumption could provide nutritional requirements necessary for proper growth as well as adequate protection against diseases caused by malnutrition.

The role of orphan crops in the transition to nutritional quality-oriented crop improvement

Micronutrient malnutrition is a persisting problem threatening global human health. Biofortification via metabolic engineering has been proposed as a cost-effective and short-term means to alleviate this burden. There has been a recent rise in the recognition of potential that underutilized, orphan crops can hold in decreasing malnutrition concerns. Here, we illustrate how orphan crops can serve as a medium to provide micronutrients to populations in need, whilst promoting and maintaining dietary diversity. We provide a roadmap, illustrating which aspects to be taken into consideration when evaluating orphan crops. Recent developments have shown successful biofortification via metabolic engineering in staple crops. This review provides guidance in the implementation of these successes to relevant orphan crop species, with a specific focus on the relevant micronutrients iron, zinc, provitamin A and folates.

Folates in various African foods: Contents, food processing and matrix effects

Poor folate status is implicated in a wide variety of health disorders including megaloblastic anaemia, neural tube defects, and cardiovascular diseases. Human diet remains the main provider par excellence. Despite several public-health options to overcome this micronutrient deficiency, dietary folate intakes of women of childbearing age and children are still below recommendations in many African countries. Therefore, this review aims at presenting the current knowledge on folate contents in various African foods, and on folate losses during food processing. Seventy one food sources were evaluated in this study. These various food sources included thirty six vegetables, six cereals, height cereal products, six processed leafy vegetables, six pulses, three fruits, three legumes and three roots. All of them were originated from six African countries including Burkina Faso, Côte d'Ivoire, Egypt, Ethiopia, Nigeria, and South Africa. Folate content ranged between 11 and 73.4 μg/100 g in cereals, 1.8 and 39 μg/100 g in cereal-based processed foods, 8.48 and 48.6 μg/100 g in cooked leafy vegetables, 11.6 and 633 μg/100 g in vegetables, 10 and 22 μg/100 g in pulses, 52 and 148 μg/100 g in legumes, 8 and 106 μg/100 g in fruits. The structure of the food matrix has been shown to influence folate digestibility in foods. High bioaccessible folate, assessed by in vitro digestion, was observed among food products with dense porosity structures while low bioaccessible folate was recorded among food products with open porous structures such as porridges and some gelatinized doughs. Numerous food processing steps have also been shown to influence negatively folate contents in foods.

Cultural Influences on African Migrant Pregnant and Postnatal Women's Dietary Behaviours and Nutrition Support Needs in the UK

Black women in the UK face significantly higher risks of overweight and obesity and adverse pregnancy outcomes compared to women from other ethnic groups. Maternal nutrition plays a pivotal role in influencing the health outcomes of women and their children, especially during preconception and pregnancy. Cultural and environmental factors significantly influence the dietary experiences of African women after migration. This study explored the unique nutrition-related challenges faced by African migrant pregnant and postnatal women in the UK, and their nutrition support needs. Interviews were conducted with 23 African migrant women living in the UK, who were either pregnant or had a pregnancy within the past 3 years. These were analysed thematically, resulting in five overarching themes: food rituals and beliefs, pregnancy cravings, limited access to culturally appropriate food, limited access to culturally appropriate and evidence-based nutritional guidance, and the focus on healthy weight. The study identified challenges that African migrant women face in balancing their cultural heritage with the UK food environment and dietary recommendations, including potential implications on their health and pregnancy outcomes. It emphasised the importance of addressing these challenges through culturally sensitive approaches and tailored interventions, to enable informed decision making and enhance health outcomes for these women.

Antioxidant Capacity of Polar and Non-Polar Extracts of Four African Green Leafy Vegetables and Correlation with Polyphenol and Carotenoid Contents

In sub-Saharan Africa, chronic malnutrition is often associated with intestinal inflammation and oxidative stress. African green leafy vegetables (GLVs), commonly consumed by these populations and rich in bioactive compounds, may improve the antioxidant status. The aim of this study was to measure the antioxidant capacity using complementary assays (DPPH, FRAP, ABTS, ORAC and NO scavenging) in polar and non-polar leaf extracts of four African GLVs, cassava (Manihot esculenta), roselle (Hibiscus sabdariffa), jute mallow (Corchorus olitorius), and amaranth (Amaranthus spp.), with spinach (Spinacia oleracea) chosen as a reference. Their antioxidant capacity was correlated with their total polyphenol (TPC), flavonoid (TFC), condensed tannin, lutein, and β-carotene contents. Identification of phenolic compounds by UHPLC-DAD-MS/MS revealed the presence of three main classes of compound: flavonols, flavones, and hydroxycinnamic acids. Cassava and roselle leaves presented significantly higher TPC and TFC than amaranth, jute mallow, and spinach. They also exhibited the highest antioxidant capacity, even higher than that of spinach, which is known for its important antioxidant effect. The antioxidant capacity was 2 to 18 times higher in polar than non-polar extracts, and was more strongly correlated with TPC and TFC (R > 0.8) than with β-carotene and lutein contents. These findings provide new data especially for cassava and roselle leaves, for which studies are scarce, suggesting an appreciable antioxidant capacity compared with other leafy vegetables.

Morpho-physiological and biochemical characterization of African spider plant (Gynandropsis gynandra (L.) Briq.) genotypes under drought and non-drought conditions

The African spider plant (Gynandropsis gynandra (L.) Briq.) is a nutrient-dense, climate-resilient indigenous vegetable with a C4 carbon fixation pathway. Understanding African spider plant drought tolerance mechanisms is essential for improving its performance in water-stressed areas. The objective of this study was to evaluate the stress tolerance potential of African spider plant accessions based on thirteen morphological, physiological, and biochemical traits under three different water treatment regimes. Eighteen accessions were evaluated over two growing seasons in the greenhouse using a split-split plot design with four replications and three water treatment-regimes namely optimum (100% field capacity), intermediate drought (50% field capacity) and, severe drought (30% field capacity). The results revealed that water regime had a significant effect (P< 0.01) on the accessions for the traits studied. A significant reduction across most of the studied traits was observed under drought conditions. However, proline content in all the accessions significantly rose under drought conditions. The principal component analysis revealed a considerable difference in the performance of the 18 African spider plant accessions under optimum and drought stress conditions. Several morphological and physiological parameters, including days to 50% flowering (r = 0.80), leaf length (r = 0.72), net photosynthesis (r = 0.76) and number of leaves per plant (r = 0.79), were positively associated with leaf yield under drought conditions. Cluster analysis categorized the 18 accessions and 13 measured parameters into 4 clusters, with cluster-1 exhibiting greater drought tolerance for most of the studied traits, and cluster-4 having the most drought-sensitive accessions. Among the accessions tested, accessions L3 and L5 demonstrated excellent drought tolerance and yield performance under both conditions. As a result, these accessions were selected as candidates for African spider plant drought tolerance breeding programs. These findings will serve as the foundation for future studies and will aid in improving food and nutrition security in the face of drought.

Hydrothermally-treated soybean-fortified maize-based nsima (stiff porridge) could contribute towards alleviating seasonal body weight loss in farming communities in sub-Saharan Africa

Objective

This study explored the use of hydrothermally-treated soybean-fortified maize-based stiff porridge (nsima) in managing body weight losses among the farming family community in Malawi during the labour-intensive cropping (growing) season. We hypothesized that soybean-fortified maize-based nsima could prevent seasonal body weight losses in farming communities during labour-intensive seasons better than conventional 100% maize nsima.

Research methods & procedures

A single-blind parallel dietary intervention 90-day study. During energy stress months, 42 farming households in Malawi were supplied with 15 kg of blind formulation of soybean-fortified maize flour (soybean: maize, 1:4, wt/wt) per person per month except for under-fives who were allotted half the quantity. Forty households were provided with equivalent quantities of 100% maize flour and served as control. Body weights of participants were taken at baseline and endpoint.

Results

After 3 months, the experimental group registered 3.7, 4.2, 2.9, and 5.2% statistically higher body weight compared to the controls for the under-five, the 5-9-year-olds, the 10-19-year-olds, and the >20-year-olds, respectively.

Conclusion

Soybean-fortified stiff porridge could feasibly be used to alleviate wasting among the resource-constraint populace in Malawi and many other parts of sub-Saharan Africa that rely on maize as a major staple.

Plant-based traditional foods and beverages of Gumare Village, Botswana

The consumption of traditional and indigenous foods and beverages varies across different ethnic communities and is often influenced by geographical location. However, the diversity of edible plants is rapidly declining due to climate change, leading to a loss of knowledge about useful plants used by different communities before the plant itself becomes extinct. This research investigated the edible plant types and investigated the processing steps of plant-based traditional foods/dishes and beverages of Gumare village, located in the catchment area of the Okavango Delta in the northwest of Botswana. Questionnaire interviews and focus group discussions (FGD) were used to collect data. The study identified 52 wild and 19 domesticated edible plants used in the preparation of traditional foods/dishes and beverages of Gumare village. Maize, sorghum, millets, beans, melon, watermelon, pumpkin, bottle gourd and sweet potato are widely used domesticated crops. The wild edible plants are either directly used after minor processing or as recipes in traditional dishes and/or as an inoculum in the fermentation, as a substrate in traditional beverages and some as medicinal plants. However, some taboos and food safety challenges were observed in the use of certain plants. The study highlighted a decline in the use of traditional foods/dishes and beverages, particularly among the young generation. The youth indicated that they have a low interest in gathering traditional foods and beverages due to the time-consuming nature during harvesting and the labour-intensive processing. In addition, they indicated the dangers of attacks by wild animals from veld by reptiles (for example snakes and pythons) and alligators (crocodiles) from rivers during the harvesting of raw materials used in traditional foods and dishes. For the communities, the diverse edible wild plants documented are a source of nutrients and bioactive compounds such as dietary fibers, phenolics, terpenes, essential oils, carotenoids, and alkaloids that help to combat malnutrition and for use as traditional medicines to support health and wellness. In conclusion, the significant diversity of wild edible plants and domesticated crops in Gumare village, likely due to its location in the catchment area of the Okavango Delta, plays a crucial role in diet diversification and can contribute to food and nutrition security. However, for most wild edible plants of Botswana, information on their nutrient and bioactive compounds are still limited. This study provides baseline information for further chemical investigation and development of resources in the formulation of functional foods and nutraceuticals.

Graphical Abstract

Can consumption of local micronutrient- and absorption enhancer-rich plant foods together with starchy staples improve bioavailable iron and zinc in diets of at-risk African populations?

Iron and zinc deficiencies remain prevalent in developing countries, often due to monotonous starchy diets that are low in bioavailable minerals. This review addresses the question as to whether consumption of starchy staple foods in Africa together with micronutrient-dense and absorption enhancer-rich plant foods can enhance iron and zinc bioavailability in the diets of at-risk populations. While green leafy vegetables (GLVs) fortification of starchy staples can improve mineral contents, especially iron, it may not improve bioavailable iron and zinc, due to GLVs' high contents of mineral absorption inhibitors, notably polyphenols, phytate and calcium. Fruits, although low in minerals, could improve bioavailable iron and zinc in the staples because of their high ascorbic and citric acid and/or β-carotene contents, which can form soluble chelates with the minerals. More human studies are needed to establish whether such a technology or fortification strategy can improve bioavailable iron and zinc in African-type plant-based diets.

The effect of coconut coir substrate on the yield and nutritional quality of sweet peppers (Capsicum annuum) varieties

The industry standard for estimating the quantity of horticultural produce harvested is crop yield. Producing sufficient amounts of high-quality biochemical ingredients crops can therefore aid in resolving concerns with food security and nutrition. Most producers prefer the use of organic substrate over natural soils when growing crops such as peppers in greenhouses, to ensure that there is a sufficient supply of food all year round. The objective of the study was to determine the effect of coconut coir substrate on the yield and biochemical constituents of peppers varieties grown under greenhouse environment. For two successive seasons [2021 and 2022], two sweet pepper types (Sondela and Ilanga) were cultivated on fertigated coconut coir and loamy soil (control). Fruit number, together with their dry weight and some biochemical constituents, were examined. To evaluate the impact of coconut coir substrate on the growth, yield, and biochemical constituents of different pepper cultivars grown in a greenhouse, dry plant materials and freeze-dried fruit samples were analyzed. Results showed that the coconut coir and variety (Ilanga) treatment combination produced more fruits than other treatments. Biochemical constituents such as vitamins, total phenols, total flavonoids, copper, iron and Zinc were in fruits grown under coir substrate when compared to loamy soil (control). Therefore, farmers are encouraged to grow sweet peppers varieties under coconut coir substrate for better yield, nutritional quality and profit maximisation.

Can cereal-legume intercrop systems contribute to household nutrition in semi-arid environments: A systematic review and meta-analysis

Introduction

Intercropping cereals with legumes can intensify rainfed cereal monocropping for improved household food and nutritional security. However, there is scant literature confirming the associated nutritional benefits.

Methodology

A systematic review and meta-analysis of nutritional water productivity (NWP) and nutrient contribution (NC) of selected cereal-legume intercrop systems was conducted through literature searches in Scopus, Web of Science and ScienceDirect databases. After the assessment, only nine articles written in English that were field experiments comprising grain cereal and legume intercrop systems were retained. Using the R statistical software (version 3.6.0), paired t-tests were used to determine if differences existed between the intercrop system and the corresponding cereal monocrop for yield (Y), water productivity (WP), NC, and NWP.

Results

The intercropped cereal or legume yield was 10 to 35% lower than that for the corresponding monocrop system. In most instances, intercropping cereals with legumes improved NY, NWP, and NC due to their added nutrients. Substantial improvements were observed for calcium (Ca), where NY, NWP, and NC improved by 658, 82, and 256%, respectively.

Discussion

Results showed that cereal-legume intercrop systems could improve nutrient yield in water-limited environments. Promoting cereal- legume intercrops that feature nutrient-dense legume component crops could contribute toward addressing the SDGs of Zero Hunger (SDG 3), Good Health and Well-3 (SDG 2) and Responsible consumption and production (SDG 12).

Effect of Common Cooking and Drying Methods on Phytochemical and Antioxidant Properties of Corchorus olitorius Identified Using Liquid Chromatography-Mass Spectrometry (LC-MS)

In this study, Corchorus olitorius leaves were subjected to different thermal treatments (blanching, boiling, drying, frying, and steaming) and analyzed, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Furthermore, Fourier transform infrared spectroscopy (FTIR) was used to identify functional groups, while metabolites were identified with LC-MC. The TPC and antioxidant activity of C. olitorius were significantly (p < 0.05) increased by cooking and drying. The steam-cooked sample had the highest TPC (18.89 mg GAE/g) and TFC (78.42 mg QE/g). With ABTS, FRAP, and DPPH assays, the steam-cooked sample exhibited the highest antioxidant activity of 119.58, 167.31, and 122.23 µM TE/g, respectively. LC-MS identified forty-two (42) metabolites in C. olitorius that included phenolic acid derivatives, flavonoid derivatives, and amino acid derivatives. Overall, steaming appears to be the best cooking method, with respect to the retention of phytochemical compounds and antioxidant activity.

Prospective Role of Indigenous Leafy Vegetables as Functional Food Ingredients

Indigenous leafy vegetables (ILVs) play a pivotal role in sustaining the lives of many people of low socio-economic status who reside in rural areas of most developing countries. Such ILVs contribute to food security since they withstand harsher weather and soil conditions than their commercial counterparts and supply important nutrients such as dietary fibre, vitamins and minerals. Furthermore, ILVs contain bioactive components such as phenolic compounds, flavonoids, dietary fibre, carotene content and vitamin C that confer health benefits on consumers. Several studies have demonstrated that regular and adequate consumption of vegetables reduces risks of chronic conditions such as diabetes, cancer, metabolic disorders such as obesity in children and adults, as well as cardiovascular disease. However, consumption of ILVs is very low globally as they are associated with unbalanced and poor diets, with being food for the poor and with possibly containing toxic heavy metals. Therefore, this paper reviews the role of ILVs as food security crops, the biodiversity of ILVs, the effects of processing on the bioactivity of ILVs, consumer acceptability of food derived from ILVs, potential toxicity of some ILVs and the potential role ILVs play in the future of eating.

Antidiarrheal Activity of Dialium guineense Willd Fruit Pulp in Wistar Rats

Objective. This study is aimed at evaluating the effects of Dialium guineense Willd fruit pulp powder on diarrhea induced by castor oil in Wistar rats. Materials and Methods. Three different tests were carried out. A preventive test by administration of a single dose of 250, 500, 1000, 2000, and 4000 mg/kg before the induction of diarrhea by castor oil. Another preventive test after repeated administration of Dialium guineense at 250, 500, and 1000 mg/kg/day for 8 days, before the induction of diarrhea, was done. The third test was a curative test with a single dose of 250, 500, 1000, and 2000 mg/kg after the induction of diarrhea by castor oil. Results. D. guineense fruit pulp at 1000, 2000, and 4000 mg/kg administered before the induction of diarrhea, has significantly delayed diarrhea; reduced the frequency of defecation, reduced the amount of diarrheal stools, and also reduced the purging index, with a degree of inhibition comparable to that of loperamide. But the water content of the stools of the group treated with D. guineense does not change significantly compared to the controls. D. guineense has reduced significantly from 500 mg/kg the diarrhea induced by castor oil after 8 days of treatment. It appears that the doses of 250 and 500 mg/kg, which were not effective with the single-dose preventive test, significantly delayed diarrhea; reduces the frequency of diarrheal stools and also reduces the purging index. D. guineense administered, after the induction of diarrhea, by castor oil has significantly reduced the diarrhea from 250 mg/kg. Conclusion. The fruit pulp of D. guineense has showed antidiarrheal activities in Wistar rats by reducing the frequency of defecation, the amount of diarrheal fecal matter emitted as well as the water content. It also delayed the onset of diarrhea and significantly reduced the purging index like loperamide.

An explorative study with convenience vegetables in urban Nigeria—The Veg-on-Wheels intervention

Nigerian consumers have been found to view vegetables as healthy and health is a principal motivation for consumption; however, consumers also experience barriers related to preparation time and availability of vegetables. We therefore conducted a Veg-on-Wheels intervention, in which ready-to-cook, washed and pre-cut green leafy vegetables (GLV) were kept cool and sold for five weeks at convenient locations near workplaces and on the open market in Akure, Nigeria. Surveys were conducted prior to the intervention with 680 consumers and during the final week of the intervention with 596 consumers near workplaces and 204 consumers at the open market. Both buyers and non-buyers of the intervention were included; 49% buyers in the workplace sample and 47% in the open market sample. The Veg-on-Wheels intervention was successful, with high awareness, positive attitudes and high customer satisfaction. GLV intake was higher for Veg-on-Wheels buyers compared with non-buyers after the intervention, i.e., 10.8 vs. 8.0 portions per week, respectively. Also the intake of other vegetables was higher in the intervention group. The motives and barriers for buyers and non-buyers differed across the selling locations: main barriers were trust in the vendor and GLV source. These trust issues and vendor preferences were viewed as more important to respondents at the market than those near workplaces. This study is the first intervention study on the selling of ready-to-cook convenience vegetables in urban Nigeria. It shows that a market exists for convenience vegetables and that they have the potential to increase vegetable intake. Insights on both the food environment and consumers’ motives and behaviour was crucial for designing and evaluating the intervention.

Cleome gynandra: A wonder climate-smart plant for nutritional security for millions in semi-arid areas

Spider plant (Cleome gynandra) is predominantly used as a traditional leafy vegetable throughout Africa and is considered a rich natural source of essential nutrients such as vitamins, minerals and proteins. With the increase in malnutrition, diet related non-communicable diseases and poverty across the continent of Africa, the spider plant is a bona fide alternative healthy food crop to alleviate these challenges. Spider plant is an erect annual herb that could grow up to 150 cm tall, strongly branched, with a long taproot and few secondary roots. It is commonly consumed in resource-poor communities especially during times of major food scarcity. It is a drought-tolerant and resilient annual vegetable crop capable of growing well in a wide range of climatic and edaphic conditions. Despite the potential benefits and wide adaptability, progressive attempts towards the development of C. gynandra as a crop have been impeded by issues like low investment in research and development resulting in poor seed quality, relatively low yields and susceptibility to pests and diseases. In this paper, we reviewed the research that has been done regarding its morphology, growing conditions, production and utilisation (i.e., nutrition). The current review highlighted the status of the science in advancing the domestication of C. gynandra as a potential power crop for several African countries. The review concluded that with the advancement of modern biotechnology techniques and genome sequencing, there is a compelling case for investment and development in C. gynandra as a candidate for managing micronutrient deficiencies during the post-pandemic era. Finally, the existing knowledge gaps (e.g., breeding) that necessitate explorations were identified and recommendations that could enhance its development and potential commercialisation were made.

A review on the potential of underutilized Blackjack (Biden Pilosa) naturally occurring in sub-Saharan Africa

Several Indigenous edible vegetables in sub-Saharan countries have potential bioactive compounds, including underutilized Biden pilosa (BP). Bioactives from Indigenous edible vegetables are re-evolving as an alternative medicine potential for drug formulations. BP has also been used to mitigate over 40 different diseases in people and animals as herbal medication. Due to globalization and urbanization, people move from more active to more sedentary lifestyles, home-cooked meals to fast foods and snacks, organic foods to processed food with high sugar, salt, and fat. The consumption of native fruits and vegetables is now replaced by a highly processed calory diet, leading to metabolic syndromes such as diabetes, obesity, and other diet-related non-communicable diseases. Hence this article was designed to investigate the existing reports on the use, knowledge and the need to utilize the potentiality of BP further to overcome nutritional deficiencies, food scarcity and mitigation of medical conditions in sub-Saharan Africa. The use of plant-based drugs will aid to decrease the health capitation load as most countries do not have enough funds for purchasing synthetic chemicals used to mitigate diseases.

Leafy vegetables fortification enhanced the nutritional profile and reduced the glycemic index of yellow cassava pasta

Food-to-food fortification of yellow cassava flour with leafy vegetable powders (Amaranthus and Telfairia occidentalis) was employed in this study to develop cassava-vegetable spaghetti-like pasta products (YP, YPA5, YPA10, YPU5, YPU10, YPA5O). The nutritional profile, micronutrient retention, bioaccessibility, starch digestibility and in vitro glycemic index were assessed. The incorporation of leafy vegetable powder enhanced the nutritional quality of the yellow cassava pasta (YCP) products. The fortification increased (up to 3-fold) the protein in fortified YCP, increased the fibre (11%), doubled the ash and increased the beta-carotene (about 7-fold), iron (72%) and zinc contents by 10%. The phenolic content of fluted pumpkin leaf-fortified pasta with 10% leaf powder inclusion (YPU10) was 1100 μg GAE g^-1, almost four times higher than that of the unfortified YCP. Leaf powders in the cassava pasta also favoured the retention of micronutrients during cooking and slowed down the starch digestibility. The retention during cooking was up to 91% in YPU10 for beta-carotene with no loss in iron, while the bioaccessibility of beta-carotene was impeded, the zinc retention was high and became significantly more bioaccessible with leaf addition and cooking. The estimated glycemic index of YCP was reduced by 19% and 15% in YPU10 and YPA10, respectively. The inclusion of the vegetables also reduced the glycemic index of the fortified YCP. Thus, adding leafy vegetable powder up to 10% into YCP is a promising approach to both valorise yellow provitamin A biofortified cassava and enhance the nutritional value.

Assessment of Mineral Nutrient Efficiency in Genetically Diverse Spinach Accessions by Biochemical and Functional Marker Strategies

Leafy vegetable crops are considered as a natural source of mineral nutrients that could decrease the risk factor of many growth issues in children and adults. Spinach is globally considered as the most desirable leafy crop, due to its taste and nutrient richness along with greater nitrate contents and better nitrogen use efficiency. To evaluate the mineral nutrient efficiency of this crop, thirty genetically diverse spinach accessions were analyzed through nutritional and functional marker strategies. The accession 163,310 from Pakistan was found to be rich in minerals (sodium, calcium, potassium, zinc, and manganese) and nitrates. However, the oxalate contents were lesser in the accessions that had greater quantity of nutrients. These represented a negative correlation between mineral availability and oxalate accumulation in the leaves. To study the relationship of oxalates and minerals in the accessions, a functional marker analysis was performed, based on the genes involved in oxalate metabolism and disease resistance in spinach. High level of genetic polymorphism was observed among the accessions represented with 115 polymorphic bands out of 130 bands. Heat map clustering represented the accessions from Asian countries (Pakistan, India, China, and Iran) as the most adaptable accessions to the local environment. The correlation between nutritional and genetic analysis also revealed the nutrient richness of these accessions along with good oxalate metabolism and disease resistance. Hence, these accessions could be considered as useful genotypes in future breeding programs.

Major Production Constraints and Spider Plant [Gynandropsis gynandra (L.) Briq.] Traits Preferences Amongst Smallholder Farmers of Northern Namibia and Central Malawi

Spider plant (Gynandropsis gynandra (L.) Briq.) is among the most important African Leafy Vegetables (ALVs) as a source of essential nutrients with the potential of contributing significantly to household food and nutritional security and mitigation of hidden hunger. Nevertheless, the vegetable is considered an orphan crop and its production is challenged by inadequate research to identify and improve traits preferred by smallholder farmers. The research was conducted to identify the main challenges impacting the production of spider plants and identify traits preferred by smallholder farmers in northern Namibia and central Malawi for use in demand-led crop improvement. Semi-structured interviews involving a random selection of 197 farming households from five regions of northern Namibia and three districts of central Malawi were conducted. In addition, six key informant interviews and four focus group discussions were conducted to triangulate the findings. Data were analyzed using IBM SPSS version 20. Fischer's exact test was used to test for independence in the ranking of production constraints and agronomic traits, while Kendall's Coefficient of Concordance (W) was used to measure agreement levels in the ranking across the countries. Farmers indicated lack of seed, poor soil fertility, poor seed germination and drought as the main production challenges across the two countries. Production constraints were ranked differently (p &lt; 0.001) across the study sites suggesting the influence of biophysical and socio-economic factors associated with production. High yield and drought tolerance were considered the most important agronomic traits among the smallholder farmers in both countries. The findings of this study are useful for designing demand-driven pre-breeding trials that prioritize the needs of the end-users. Demand-led breeding has the potential to stimulate the production and utilization of spider plant, hence contributing to household food and nutritional security.

Indigenous Foods of India: A Comprehensive Narrative Review of Nutritive Values, Antinutrient Content and Mineral Bioavailability of Traditional Foods Consumed by Indigenous Communities of India

India is endowed with several indigenous foods (IFs), that hold special cultural significance among local and ethnic caommunities, yet no attempts have been made till date to systematically compile their nutritive values. As per FAO's recent mandate on creation of “Global-Hub on Indigenous Food Systems,” IFs have received renewed global recognition for their potential to contribute to improved food security while enhancing biodiversity across the world. Hence, the useful properties of wild IFs require proper study and documentation in order to bridge the gap between scientific evidence generation and indigenous peoples' ancestral knowledge. For this purpose, we conducted a literature search in two scientific databases: PubMed and Google Scholar, between July 2020 and December 2021, to identify studies reporting nutritive values and/or antinutrient content of IFs (not included in Indian food composition database), consumed by Indian indigenous communities. A total of 52 Indian research articles were included, from which data was selected and extracted, to create a compendium on nutrient (n = 508) and antinutrient (n = 123) content of IFs, followed by computation of antinutrient-to-mineral molar ratios for 98 IFs to predict their mineral bioavailability. Maximum nutritive values were available for green leafy vegetables (n = 154), followed by other vegetables (n = 98), fruits (n = 66), cereals (n = 63), roots &amp; tubers (n = 51) and nuts and legumes (n = 36). Several IFs seen to have better nutritional content than conventional foods and were found to be rich (i.e., &gt;20% Indian recommended dietary allowances per reference food serve) in iron (54%), calcium (35%), protein (30%), vitamin C (27%), vitamin A (18%), zinc (14%) and folate (13%). Some IFs displayed high levels of antinutrients, however, anti-nutrient-to-mineral molar ratios were found to be low (for mainly leafy vegetables, other vegetables, and roots and tubers), thus indicating high mineral bioavailability. Hence, efforts are desirable to encourage the inclusion of these nutritionally superior IFs into the usual diets of indigenous communities. The IF database collated in our review can serve as a resource for researchers and policymakers to better understand the nutritional properties of region-specific IFs and promote them through contextual food-based interventions for improved dietary quality and nutrition outcomes in indigenous population of India.

A Comparison of Bioactive Metabolites, Antinutrients, and Bioactivities of African Pumpkin Leaves (Momordica balsamina L.) Cooked by Different Culinary Techniques

Prior to consumption, African pumpkin leaves (Momordica balsamina L.) are generally cooked. In this study, the effects of common household cooking methods (boiling, steaming, microwaving, stir-frying) on bioactive metabolites, carotenoids, antioxidant activity, antinutrients and inhibitory effects on α-glucosidase and α-amylase activities were examined. A set of 14 bioactive metabolites were identified in raw and cooked African leaves using UPLC-QTOF/MS. The results showed that the four different types of household cooking methods had different effects on the bioactive metabolomics profile of African pumpkin leaves. In comparison to raw leaves and leaves cooked in other methods, the concentrations of six phenolic compounds, rutin, cryptochlorogenic acid (4-caffeoylquinic acid), pseudolaroside A, isorhamnetin 3-O-robinoside, quercetin 3-galactoside, and trans-4-feruloylquinic acid, were highest in stir-fried leaves. Of all household cooking methods tested, stir-frying increased the content of lutein, β-carotene, and zeaxanthin by 60.00%, 146.15%, and 123.51%, respectively. Moreover, stir-frying African pumpkin leaves increased the antioxidant activity (DPPH and ABTS) and the inhibition of α-glucosidase and α-amylase. Compared to all four methods of household cooking, stir-frying reduced the antinutritive compounds compared to raw leaves. This work provides useful information to the consumers on the selection of suitable cooking methods for African pumpkin leaves.

Implementing a 'Vegetables First' Approach to Complementary Feeding

Purpose of Review

To provide a rationale for promoting a vegetables first approach to complementary feeding (CF), building on prior exposure to vegetable flavours experienced in utero and via breastfeeding (chemosensory continuity).

Recent Findings

Vegetables confer selective health benefits but population intakes are below recommendations globally; maternal intake of vegetables during both pregnancy and lactation promotes familiarity with some vegetable flavours. Building on this exposure, vegetables as a first food during CF further promote acceptance. However, experiments testing efficacy of a vegetables first approach to CF demonstrate increased liking and intake, some evidence of generalisability but little evidence of sustained effects beyond infancy.

Summary

The aim to increase the quantity and variety of vegetables eaten by children is both desirable, to improve nutrient quality of the diet, and achievable. However, longer, larger, randomised control trials are needed to evidence any longer term, sustainable benefits to liking and intake of vegetables.

Ethnobotanical Uses, Nutritional Composition, Phytochemicals, Biological Activities, and Propagation of the Genus Brachystelma (Apocynaceae)

The Brachystelma genus (family: Apocynaceae) consists of geophytes that are traditionally utilised among rural communities, especially in East Africa, southern Africa, West Africa, and northern and western India. Apart from being used as a food source, they are indicated as treatment for ailments such as colds, chest pains, and wounds. This review provides a critical appraisal on the ethnobotanical uses, nutritional value, phytochemical profiles, and biological activities of Brachystelma species. In addition, we assessed the potential of micropropagation as a means of ensuring the sustainability of Brachystelma species. An inventory of 34 Brachystelma species was reported as a source of wild food and traditional medicine (e.g., respiratory-related conditions, pains, and inflammation) across 13 countries, predominantly in Africa and Asia. Brachystelma circinnatum and Brachystelma foetidum were the most popular plants based on the high number of citations. Limited data for the nutritional content was only available for Brachystelma edulis and Brachystelma naorojii, as well as phytochemical profiles (based on qualitative and quantitative techniques) for five Brachystelma species. Likewise, a few Brachystelma species have evidence of biological activities such as antimicrobial, antioxidant, and acetyl cholinesterase (AChE) inhibitory effects. Extensive studies on Brachystelma togoense have resulted in the isolation of four compounds with therapeutic potential for managing different health conditions. As a means of contributing to the sustainability of Brachystelma species, micropropagation protocols have been devised for Brachystelma glabrum, Brachystelma pygmaeum, Brachystelma ngomense, and Brachystelma pulchellum. Nevertheless, continuous optimisation is required to enhance the efficiency of the micropropagation protocols for these aforementioned Brachystelma species. Despite the large number of Brachystelma with anecdotal evidence as food and medicine, a significant number currently lack empirical data on their nutritional and phytochemical profiles, as well as their biological activities. The need for new propagation protocols to mitigate the declining wild populations and ensure their sustainability remains pertinent. This is important should the potential of Brachystelma species as novel food and medicinal products be achieved.

Neglected and Underutilised Crops: A Systematic Review of Their Potential as Food and Herbal Medicinal Crops in South Africa

The African continent harbours many native species with nutraceutical and pharmaceutical potential. This study reviewed underutilised crops in South Africa to determine their potential as food and herbal medicinal crops. Over 5,000 species have been identified and earmarked for their medical attributes in formal and informal setups. Researchers, plant breeders and policymakers have mostly ignored the development potential of these crops. Consequently, their value chains are poorly developed. In South Africa, there is a wide range of neglected and underutilised crops, which were historically popular and used by communities; however, over the years, they have lost their status within farming systems and been relegated to the status of neglected and underutilised. Recently, driven by the need to transition to more sustainable and resilient food systems, there has been renewed interest in their potential as food and herbal medicinal crops to establish new value chains that include vulnerable groups. They are now gaining global attention, and their conservation and sustainable utilisation are now being prioritized. The review confirmed that several of these crops possess nutraceutical and pharmaceutical properties, highlighting their potential for development as food and herbal medicines. However, current production levels are too low to meet the requirements for industrial development; research and development should focus on all aspects of their value chain, from crop improvement to utilisation. A transdisciplinary approach involving a wide range of actors is needed to develop the identified neglected and underutilised crops' potential as food and herbal medicinal crops and support the development of new and inclusive value chains.

Potential Role of African Fermented Indigenous Vegetables in Maternal and Child Nutrition in Sub-Saharan Africa

Hunger and malnutrition continue to affect Africa especially the vulnerable children and women in reproductive age. However, Africa has indigenous foods and associated traditional technologies that can contribute to alleviation of hunger, malnutrition, and communicable and noncommunicable diseases. The importance of African indigenous vegetables is undeniable, only that they are season-linked and considered as "food for poor" despite their high nutritional contents. The utilization of African indigenous vegetables (AIVs) is hindered by postharvest losses and antinutrients affecting the bioavailability of nutrients. In Africa, fermentation is among the oldest food processing technologies with long history of safe use. Apart from extending shelf life and improving food organoleptic properties, fermentation of African indigenous vegetables (AIVs) is known to improve food nutritional values such as proteins, minerals, vitamins, and other beneficial phytochemicals. It can also increase bioavailability of various vitamins, minerals, and phytochemicals and increase synthesis of vital blood pressure regulators thus protecting against cardiovascular diseases and cancer and further helping fight certain malnutrition deficiencies. Some lactic acid bacteria (LAB) involved in food fermentation are known to produce exopolysaccharides with cholesterol-lowering, immunomodulator, antioxidant, and anticancer properties. Fermented foods (vegetables) are superior in quality and safety since most microorganisms involved in fermentation are good starter cultures that can inhibit the growth of foodborne pathogens and detoxify harmful compounds in foods. Thus, fermented foods can boost growth and well-being in children and women due to their higher nutritional contents. Therefore, fermentation of AIVs can contribute to the attainment of food and nutrition security especially among women and children who rely on these vegetables as a staple source of micronutrients and income. These benefits have a positive impact on the implementation of the second sustainable development goals and African Union agenda 2063. This review is aimed at shedding light on the potential of African fermented indigenous vegetables in combating maternal and child malnutrition in Sub-Sahara Africa.

Nutritional and Functional Properties of Wild Leafy Vegetables for Improving Food Security in Southern Angola

In Southern Angola, numerous non-woody forest products are sold at local markets, namely in Lubango (Huíla Province). Such is the case of herbaceous wild plants, locally known as lombi, which are sold fresh throughout the year and cooked as a vegetable. Although these wild leafy vegetables are commercialized and widely used in local food, there is still a lack of scientific knowledge about their properties. Thus, this study aimed to identify and characterize the species sold, and to determine their nutritional and functional properties. Our results revealed that three species—Amaranthus hybridus, Bidens pilosa, and Galinsoga parviflora—are usually sold at Lubango markets and consumed by local populations. These are annual exotic plants, native to Southern America, and usually occur spontaneously in croplands or disturbed areas, but can also be cultivated, particularly A. hybridus. Physico-chemical analyses of lombi species and mixtures sold at the markets included measurements of moisture, protein, lipid, and mineral content, as well as total phenolic content, antioxidant activity, and levels of heavy metal contaminants. The results revealed that lombi contain a significant amount of protein (20–28 g/100 g, dry basis), high values of macronutrients and micronutrients, as well as of phenolic compounds (10–40 mg GAE/g) and a good antioxidant capacity. Given the availability of lombi throughout the year, our study demonstrated the importance of wild edible plants in Angola, both as a valuable natural resources and as a complementary food sources, as well as additional sources of income for many families.

Dietary Phytochemical Screening of Spider Plant (Gynandropsis gynandra (L.) Briq.) Accessions From Africa and Asia to Identify Genotypes for Use in Nutraceutical Breeding

Increased public awareness of healthy foods and healthy living, coupled with escalating medicinal costs and recent advances in research and technology, has sparked a paradigm shift to nutraceuticals, which guarantee human health and disease prevention. Spider plant (Gynandropsis gynandra) contains dietary phytochemicals with high nutritional and medicinal properties that can contribute to healthy living. A study was conducted to identify spider plant (Gynandropsis gynandra (L.) Briq.) accessions with superior levels of dietary phytochemicals and anti-oxidative activity for use in nutraceutical breeding. Thirty-three accessions of spider plant, representing a wide genetic diversity based on geographic areas of origin (Asia, East Africa, Southern Africa, and West Africa), were used. Total phenolic acids, tannins, and anthocyanins were extracted and quantified using the Folin-Ciocalteau colorimetric, spectrophotometric, and pH differential methods, respectively. Antioxidant activity was determined using phosphomolybdenum method. Results showed significant variation in levels of total phenolic compounds, tannins, anthocyanins, and antioxidant activity (P &lt; 0.05) amongst the spider plant accessions and regions of origin; ODS-15-037 (464 mg TAE/g DW), ODS-15-053 (270 mg GAE/g DW), and BC-02A (127 mg cyanidin-3-glucoside/g DW) had the highest levels of total tannins, phenolic compounds, and anthocyanins, respectively. Antioxidant activity was high in ODS-15-053 (492.2 mg AAE/100 g DW), NAM 2232 (445.3 mg AAE/100 g DW), and NAM-6 (432.5 mg AAE/100 g DW). On average, West African accessions had significantly high tannin concentrations (239 mg TAE/g DW), while Southern Africa accessions contained significantly high anthocyanin content (58.9 mg cyanidin-3-glucoside/g DW). The superior accessions are potential candidates for use in nutraceutical breeding, while the regions of origin could be used as gene pools for specific phytochemicals for improving dietary supplements of nutraceuticals. The strong antioxidant activity exhibited by spider plant accessions suggests the presence of compounds responsible for scavenging free oxygen or nitrogen radicals. Further studies are recommended to identify the chromosomal regions that contain genes controlling the dietary nutraceuticals in the genetic materials and to determine their association with foliage yield and other phenotypes, which can be utilized in spider plant improvement.

Underutilization Versus Nutritional-Nutraceutical Potential of the Amaranthus Food Plant: A Mini-Review

Amaranthus is a C4 plant tolerant to drought, and plant diseases and a suitable option for climate change. This plant could form part of every region’s cultural heritage and can be transferred to the next generation. Moreover, Amaranthus is a multipurpose plant that has been identified as a traditional edible vegetable endowed with nutritional value, besides its fodder, medicinal, nutraceutical, industrial, and ornamental potentials. In recent decade Amaranthus has received increased research interest. Despite its endowment, there is a dearth of awareness of its numerous potential benefits hence, it is being underutilized. Suitable cultivation systems, innovative processing, and value-adding techniques to promote its utilization are scarce. However, a food-based approach has been suggested as a sustainable measure that tackles food-related problem, especially in harsh weather. Thus, in this review, a literature search for updated progress and potential uses of Amaranthus from online databases of peer-reviewed articles and books was conducted. In addition, the nomenclature, nutritional, and nutraceutical value, was reviewed. The species of focus highlighted in the review include, A. blitum, A. caudatus, A. cruentus, A. dubius, A. hypochondriacus, A. spinosus, A. thunbergii, A. tricolor, and A. viridis.

Evaluation of Leaf Mineral, Flavonoid, and Total Phenolic Content in Spider Plant Germplasm

Spider plant (Cleome gynandra L.) is an important leafy vegetable that grows naturally in many parts of the world. The leaves are highly nutritious and are used mainly for human consumption. The mineral content and phenolic compounds of 17 genotypes (local and exotic) of spider plant and four standards (swiss chard, jute mallow, cowpea, and pumpkin) were investigated. Leaf samples were harvested from plants raised at Thohoyandou, South Africa. Exotic genotypes were superior to local genotypes for most of the minerals. Swiss chard possessed significantly high levels of some minerals such as iron and manganese in comparison with exotic spider plant genotypes. The calcium content in the local (‘MP-B-3-CG’) and exotic (‘GPS’) genotypes was >30.0% and >60.0% higher than in swiss chard, respectively. Total phenolics among spider plant genotypes ranged from 9.86 to 12.21 mg GAE/g DW and were superior to pumpkin. In addition, the spider plant genotypes varied significantly in the antioxidant capacity as estimated by the 2,2 diphenyl-1-picrylhydrazyl method and ferric-reducing antioxidant power. The main flavonoid in the leaves of spider plant genotypes was quercetin-3-rutinoside. Crotonoside (glycoside) was detected in all the spider plant genotypes and swiss chard. A positive correlation was observed between total phenolic content and each of the three flavonoids. The PCA biplot associated exotic genotypes (‘ML-SF-29′, ‘PS’, ‘TZ-1’, and ‘GPS’) and local genotypes (‘ML-3-KK’, ‘ML-13-SDM’, and ‘ML-12-TMP’) with high Al, Fe, Zn, N, and TPC. Cluster analysis indicated high “distant groups” between exotic and local genotypes of spider plant. These results indicated that some of the local germplasm of spider plant was largely inferior to the exotic germplasm in terms of their mineral composition but contained considerable quantities of quercetin-3-rutinoside, particularly in the local genotypes ‘MP-B-2-CG’ and ‘MP-B-1-CG’. There is a need for genetic improvement of the local germplasm in some of the minerals particularly to benefit the end-users.

African Leafy Vegetables for Improved Human Nutrition and Food System Resilience in Southern Africa: A Scoping Review

The economic potential of African leafy vegetables (ALVs) remains obscured by a poorly developed value chain. This scoping review assembled and examined scattered knowledge generated on ALVs across southern Africa, focusing on production, processing, marketing, and consumption. Two electronic databases (Scopus and Web of Science) were screened, and a total of 71 relevant studies were included and evaluated. The review provides a state of the art on knowledge related to utilisation of ALVs across the entire value chain. The findings show that functional properties are of prime importance in the production and consumption of ALVs. However, the lack of improved germplasm and a non-existent seed supply system are significant production bottlenecks. Pests and diseases affecting the productivity of ALVs remain mostly unexplored. Sun-drying and boiling were the most reported post-harvest processing methods, suggesting that traditional processing methods are still prominent. Many studies also confirmed the predominance of informal markets in the trading of ALVs as they fail to penetrate formal markets because of poor product positioning and exclusion from produce demand and supply forecasts. The inception of cultivar development, mechanised processing methods, and market linkages will enhance the profitability of ALVs in the region. This review enhances the gaining of insight into the state of different value chain components will assist in upscaling production, value addition of products, and enhance marketing efficiency. There is a great opportunity for basic and applied research into ALVs.

Food Choice Behaviors of Lactating Women: Association with Body Mass Index and Fruits and Vegetables Intake in Central Amhara Region, Ethiopia-An Observational Study

BACKGROUND

What food people choose to eat is embraced by circumstances that are essentially influenced by the underlying motives of food choices which are important to a healthful dietary change. Therefore, this study aimed to explore food choice behaviors associated with nutritional status and FVs intake in women during lactation from central Amhara.

METHODS

A multistage sampling technique was applied to select study participants. A study was conducted among 423 randomly selected lactating women using a face-to-face interview of the questionnaire. A community-based cross-sectional, quantitative study with descriptive and analytical components was done. Anthropometrics measurements such as weight, height, waist, and hip circumference were taken from all participants. Body mass index was calculated to determine the nutritional status of women. Data were analyzed using SPSS version 20 computer software program. Association between dependent and independent variables was identified by logistic regression analysis, and a P-value< 0.05 was taken as statistically significant.

RESULTS

About 21.7% of women were underweight. Approximately 37.4% of women had good consumption trends to fruits and vegetables. Healthy meal eating motivation, price-consciousness, and mood concern were identified as the most significant behaviors of food choice, influencing the nutritional status of women with AOR (95% CI) of 2.1 (1.21-3.62), 3.01 (1.32-6.9), and 0.5 (0.30-0.95), respectively. Natural content (AOR (95%): 2.37 (1.39-4.06)), mood concern (AOR (95%): 2.29 (1.15-4.56)), religion concern (AOR (95%): 2.45 (1.37-4.4)), husband encouragement (AOR (95%): 2.26 (1.04-4.89)), and availability of milk and milk products (AOR (95%): 1.6 (1.39-2.74)) and fruits and vegetables (AOR (95%): 1.66 (1.16-3.48)) in home were associated significantly with a good intake of fruit and vegetables.

CONCLUSIONS

This finding provides a useful insight into the food choice motivations of a group of women with preference for natural foods, mood concern, religion concern, and husband support with good fruit and vegetable intake. This can help practitioners make recommendations for health promotion strategies. Emphasis on assisting women with healthy meal eating and avoiding psychological stress is important. Nutrition education about healthy food choice is recommended for communities.

Socioeconomic and Geographic Pattern of Food Consumption and Dietary Diversity among Children Aged 6-23 Months Old in Ghana

Dietary inadequacy is a major challenge among young children in Ghana. Nutritional policies are required for optimum child nutrition and development. This study explored food consumption and dietary diversity by socioeconomic status and geographical location among children aged 6–23 months in Ghana. We used the latest national representative, cross-sectional data from the Ghana Demographic and Health Survey (GDHS-2014). A total of 887 children aged 6–23 months were used in the final analysis. The survey collected data on children’s food consumption through their mothers in the 24 h recall method. Multiple logistic regression models were used to assess the relationship between socioeconomic status and geographical location with food consumption and adequate dietary diversity after adjusting for control variables. The study revealed an association between specific food item consumption, food groups, and dietary diversity by socioeconomic and geographic characteristics. However, dairy consumption increased faster than other nutritional foods when socioeconomic status increased. Furthermore, the study revealed that children’s chances of consuming particular food items and food groups differed across Ghana’s 10 regions. The average probabilities of consuming adequate dietary diversity between the Greater Accra region and Ashanti region were 43% vs. 8% (p < 0.001). Consumption of grains, root, and tubers were relatively higher but low for Vitamin A-rich fruits and vegetables and legumes and nuts for children aged 6–23 months in Ghana. Overall, the mean dietary diversity score was low (3.39; 95% CI: 3.30–3.49) out of eight food groups, and the prevalence of adequate dietary diversity was 22% only. There is a need for policy interventions to ensure appropriate dietary practices to promote healthy growth of children.

In vitro bioavailability-based assessment of the contribution of wild fruits and vegetables to household dietary iron requirements among rural households in a developing country setting: The case of Acholi Subregion of Uganda

Wild fruits and vegetables (WFV) are believed to contain substantial quantities of micronutrients and are commonly consumed in rural areas of developing countries endowed with natural vegetation. Previous studies that provided evidence on the contribution of WFV to household micronutrient intake in a developing country setting did not consider the effect of antinutritional factors. Therefore, applying the in vitro bioavailability assessment technique and using the Acholi subregion of Uganda a case area, this study examined the contribution of commonly consumed WFV to the pooled annual household dietary requirement for iron. Laboratory analysis showed that the concentration of antinutrients varied with plant species but the pool was dominated by phytate (10.5-150 mg/100 g) and phenolic substances (38.6-41.7 mg GAE/g). In vitro iron bioavailability varied with plant species was quantitatively higher from vegetables than fruits by 27% although total concentration of the micronutrient was higher in fruits than vegetables by 142%. Nutritional computation, taking into account, household composition, and physiological status revealed that consumption of WFV resulted in a median contribution of 1.8% (a minimum of 0.02 and a maximum of 34.7%) to the pooled annual household dietary iron requirements on the basis of bioavailable iron fraction. These results demonstrate that WFV contributes meagerly to household iron needs but may serve other dietary and non-nutrient health purposes.

Potential role of neglected and underutilized plant species in improving women's empowerment and nutrition in areas of sub-Saharan Africa

In the context of the nutrition transition, women in sub-Sahara Africa are a critical target group from a nutrition standpoint, and they experience significant discrimination in food production. Food-based, women-centered strategies are recommended to address nutrient gaps, and to educate and empower women. In this context, local natural resources, such as neglected and underutilized plant species (NUS), may contribute to adding nutritional value, enriching diet diversity, and ensuring nutrition security. The aim of the current narrative review is to investigate the nutritional status of the sub-Saharan African population and the potential role of local agriculture strategies in improving food production and diet diversity and in expanding income-generating activities for women. The nutritional properties of the most important regional NUS are also discussed.

Impact of Household Cooking Techniques on African Nightshade and Chinese Cabbage on Phenolic Compounds, Antinutrients, in vitro Antioxidant, and β-Glucosidase Activity

Different household cooking techniques (boiling, steaming, stir frying, and microwave) were tested on the changes of targeted phenolic compounds, antioxidant property (ferric reducing-antioxidant power (FRAP) activity), α-glucosidase activity, antinutritive compounds, and sensory properties in commonly consumed traditional leafy vegetables in Southern Africa, the non-heading Chinese cabbage (Brassica rapa L. subsp. chinensis) and African nightshade (Solanum retroflexum Dun). Stir frying increased kaempferol-3-O-hydroxyferuloyl-trihexoside, kaempferol-dihexoside, sinapoyl malate, rutin, and isorhamnetin-O-dihexoside in Chinese cabbage leaves, followed by steaming. Similarly, stir frying increased kaempferol-3-O-rutinoside, chlorogenic acid, caffeoylmalic acid, and quercetin-3-O-xylosyl-rutinoside in nightshade, followed by steaming. Biomarkers, sinapoyl malate (Chinese cabbage) and caffeoylmalic acid (nightshade), separated the stir frying from the other cooking techniques. Steaming and stir-frying techniques significantly increased the FRAP activity; whereas boiling and microwaving reduced the tannin, oxalate, and phytate contents in both leafy vegetables and steroidal saponins in nightshade. Stir-fried nightshade leaf extract showed the most effective inhibition against α-glucosidase activity, with an IC₅₀ of 26.4 μg ml^-1, which was higher than acarbose, a synthetic compound (positive control; IC₅₀ 69.83 μg ml^-1). Sensory panelists preferred the stir-fried Chinese cabbage and nightshade leaves, followed by steamed, microwaved, and boiled vegetables.

Free amino acids in African indigenous vegetables: Analysis with improved hydrophilic interaction ultra-high performance liquid chromatography tandem mass spectrometry and interactive machine learning

A hydrophilic interaction (HILIC) ultra-high performance liquid chromatography (UHPLC) with triple quadrupole tandem mass spectrometry (MS/MS) method was developed and validated for the quantification of 21 free amino acids (AAs). Compared to published reports, our method renders collectively improved sensitivity with lower limit of quantification (LLOQ) at 0.5~42.19 ng/mL with 0.3 μL injection volume (or equivalently 0.15~12.6 pg injected on column), robust linear range from LLOQ up to 3521~5720 ng/mL (or 1056 ~ 1716 pg on column) and a high throughput with total time of 6 min per sample, as well as easier experimental setup, less maintenance and higher adaptation flexibility. Ammonium formate in the mobile phase, though commonly used in HILIC, was found unnecessary in our experimental setup, and its removal from mobile phase was key for significant improvement in sensitivity (4~74 times higher than with 5 mM ammonium formate). Addition of 10 (or up to100 mM) hydrochloric acid (HCl) in the sample diluent was crucial to keep response linearity for basic amino acids of histidine, lysine and arginine. Different HCl concentration (10~100 mM) in sample diluent also excreted an effect on detection sensitivity, and it is of importance to keep the final prepared sample and calibrators in the same HCl level. Leucine and isoleucine were distinguished using different transitions. Validated at seven concentration levels, accuracy was bound within 75~125%, matrix effect generally within 90~110%, and precision error mostly below 2.5%. Using this newly developed method, the free amino acids were then quantified in a total of 544 African indigenous vegetables (AIVs) samples from African nightshades (AN), Ethiopian mustards (EM), amaranths (AM) and spider plants (SP), comprising a total of 8 identified species and 43 accessions, cultivated and harvested in USA, Kenya and Tanzania over several years, 2013~2018. The AN, EM, AM and SP were distinguished based on free AAs profile using machine learning methods (ML) including principle component analysis, discriminant analysis, naïve Bayes, elastic net-regularized logistic regression, random forest and support vector machine, with prediction accuracy achieved at ca. 83~97% on the test set (train/test ratio at 7/3). An interactive ML platform was constructed using R Shiny at https://boyuan.shinyapps.io/AIV_Classifier/ for modeling train-test simulation and category prediction of unknown AIV sample(s). This new method presents a robust and rapid approach to quantifying free amino acids in plants for use in evaluating plants, biofortification, botanical authentication, safety, adulteration and with applications to nutrition, health and food product development.

Diet composition and preferences of Bohor reedbuck (Redunca redunca ) in the compound of Alage College, Central Rift Valley of Ethiopia

Numerous indices have been developed to compare use and availability of foods in field diets of wild ungulates. However, little attention has been given to laboratory analysis for comparing food preferences. To this end, a study aimed at investigating the diet composition and preference of Bohor reedbuck was conducted in the compound of Alage Agricultural College, Central Rift Valley of Ethiopia from 2017 to 2018 encompassing both dry and wet seasons. Bohor reedbuck is a medium sized horned antelope species endemic to Africa. Continuous focal animal observation was used to collect the data on plant species included in the diet of Bohor reedbuck. Focal individuals' observation was carried out for 30 min in 10 min sampling interval during their active feeding period (early morning and late afternoon) over four different habitat types. The nutrient composition of plants consumed was determined using wet chemistry laboratory analysis. Bohor reedbucks consumed 15 species of plants; herbs comprised 94.3% of the foods they consumed. Digitaria abyssinica was the most preferred plant species with highest crude protein (23.75%) and less fiber (61.8% nitrogen detergent fiber and 27.8% acid detergent fiber). These findings suggest that food preference of Bohor reedbuck is determined by the nutritional content of the plant it consumed, since the area is more or less natural habitat in terms of plant species composition. For sustainable conservation of the species, there is a need to actively promote management of the plant species most preferred by the reedbuck to feed on.

Nutrient density, but not cost of diet, is associated with anemia and iron deficiency in school-age children in South Africa

OBJECTIVES

This study aimed to investigate the relationship of nutrient density and diet cost with anemia and iron deficiency (ID) in children.

METHODS

Dietary intake data of 5- to 12-y-old children (n = 578) from three independent studies in low-income communities were pooled. Nutrient densities were calculated using the Nutrient Rich Foods index and Nutrient Rich Diet index, with higher scores indicating more nutrient-dense foods and diets. Food prices and food intake data were used to calculate ratios of nutrient density to price for foods and diets. Descriptive and correlation analyses examined associations of nutrient density and diet cost with anemia and ID.

RESULTS

Most children (>50%) consumed starchy staples (100%), vegetables that are not vitamin A rich (63.9%), and legumes (58.1%), with mean NRF9.3 scores ranging from 31.9 to 56.3. Cheese, eggs, organ meat, fish, dark-green leafy vegetables, and vitamin A-rich vegetables and fruits had mean NRF9.3 scores ranging from 112.6 to 184.7, but each was consumed by less than a third of the children. Children with anemia or ID had lower NRD9.3 scores than children without (P < 0.001 and P = 0.039, respectively). Diet cost did not differ according to anemia and iron status, but nutrient-density-to-price ratio was lower in children with anemia than without (P = 0.001).

CONCLUSIONS

Careful selection of nutrient-dense foods as substitutes for foods with lower nutrient density could make it possible for children to consume a diet richer in specific nutrients and help prevent anemia and ID without affecting diet cost.

A review of micronutrient deficiencies and analysis of maize contribution to nutrient requirements of women and children in Eastern and Southern Africa

This paper reviews and analyses the importance of maize as staple food in Eastern and Southern Africa (E&SA) and contributes in understanding the nexus between maize nutritional composition and prevalence of micronutrient deficiencies (MNDs) in these regions. MNDs remain a major public health concern particularly for women and children, with calcium, iodine, iron, selenium, zinc, folate and vitamin A deficiencies being the most common. Estimates of their prevalence are among the highest in E&SA: iron-deficient anemia affected 26 to 31% of women of reproductive age, and deficiencies up to 53%, 36%, 66%, 75% and 62% for vitamin A, iodine, zinc, calcium and selenium, respectively, were measured in populations of these regions. Besides, these two regions show the highest worldwide maize per capita consumption (g/person/day) as main staple, with 157 in Eastern Africa and 267 in Southern Africa, including up to 444 in Lesotho. The analysis of food composition tables from these regions showed that 100 g of maize foods consumed by these populations could to some extent, contribute in satisfying dietary reference intakes (DRIs) of children and women in energy, proteins, carbohydrates, magnesium, zinc, vitamins B1 and B6. However, it provides very low supply of fats, calcium, sodium, selenium, vitamins C, A and E. The high occurrence of MNDs and considerable nutritional potential of maize consumed in E&SA can be explained by loss of nutrients due to processing practices, low food diversification and reduced nutrients bioavailability. Success cases of the main strategies to tackle the issue of MNDs in these regions by improving maize nutritional quality are discussed in this paper. Maize fortification was shown to improve nutrition and health outcomes of population. Increasing dietary diversity by complementing maize with other foods has improved nutrition through integration of micronutrient-rich foods in the diet. Mostly, biofortification has successfully contributed in reducing vitamin A and zinc deficiencies in rural communities more than nutrient supplementation, fortification and dietary diversity.