Nutrients and antinutrient constituents of Amaranthus caudatus L. Cultivated on different soils

Nutrients, bioactive compounds and antinutritional properties of marigold genotypes as promising functional food

The rising demand for health promoting functional foods has sparked interest in diversifying diets by incorporating innovative items like edible flowers. Considering this, the nutritional composition, bioactive properties and antinutritional factors of the flowers of eight marigold genotypes (M1 to M8) were quantified and compared to elucidate their value and safety as functional food. The study outcomes highlighted significant differences among the genotypes for most of the attributes. Anthocyanin, carotenoid and lutein contents were observed within a range of 0.02 to1.90 mg/100 g, 5.02 to 11.08 mg/100 g and 0.19 to 9.78 µg/g, respectively. The content of sugars, β-carotene, vitamins (C and E) and minerals (sodium, potassium, calcium, magnesium and iron) were also found to be present in substantial amounts. The analysis of bioactive compounds revealed the richness in total phenolic (TPC) (428.58 to 592.71 mg gallic acid equivalent (GAE)/100 g) and flavonoid content (TFC) (135.06 to 233.39 mg quercetin equivalent (QE)/100 g). Among the assessed antinutrients, alkaloid, tannin and saponin exceeded permissible limits in the studied genotypes, while phytate remained within the safe range. However, the elevated levels of these antinutrients would not pose any problem if processed through methods such as soaking, boiling or cooking. Out of eight genotypes, M1 had the highest content of anthocyanin (1.90 mg /100 g), reducing sugar (21.63 mg/100 g), and antioxidant activities. M5 stood out with the highest levels of TSS (6.10 °Brix), β-carotene (0.50 mg/100 g), vitamin C (28.61 mg/100 g), Ca (225.33 mg/100 g), and TPC (592.71 mg GAE/100 g), while M6 contained significant amounts of carotenoids (11.08 mg/100 g) and TFC (232.41 mg QE/100 g). Principal component analysis and cluster dendrogram findings further confirmed that among the eight studied genotypes, M1, M5 and M6 genotypes were found as the most prominent with the remarkable contributions of the majority of the studied variables. Hence, these marigold genotypes could be considered as promising options to improve and diversify healthy diets, potentially serving as valuable sources of dietary supplements and functional food ingredients.

Salinity Influenced Proximate, Minerals, Anti-Nutrients and Phytochemical Composition of Trachyandra ciliata Kunth (Wild Cabbage): A Promising Edible Halophyte

Climate change, drought, and soil salinization present huge limitations to global agricultural output, which threatens food security. This necessitates the cultivation and domestication of wild edible halophytes as alternatives to mainstream food crops, especially in arid and semi-arid regions. Trachyandra ciliata is one of the under-researched and underutilized edible halophytes native to South Africa. The plant was used as a food source by Khoisan people in the past although its edibility and nutritional capacity are undocumented. Thus, the current study explored the effect of varying salinity concentrations on minerals, proximate, phytochemical, and anti-nutrient composition of T. ciliata to evaluate its edibility and promote its cultivation among South African households. Plants were subjected to varying salinity treatments from 0, 50, 100,150, and 200 mM prepared by adding sodium chloride (NaCl) to the nutrient solution. Salinity significantly influenced the mineral, proximate, antinutrient, and phytochemical composition of T. ciliata. Control and 50 mM treatments recorded significantly higher macro and micronutrient content in the flower buds and leaves, except for heavy metals such as Zn and Cu, which increased with increasing salinity and significantly higher in the roots. Leaves under low salinity treatments recorded higher moisture and protein content, while leaves also recorded higher ash content under high salinity. On the other hand, flower buds under low salinity recorded significantly high fat and NDF composition. Phytochemicals and antinutrients increased with increasing salinity concentrations. The low antinutrient content and high nutritional, mineral and phenolic contents validate the edibility and suitability of T. ciliata for human consumption.

In vitro anti-HIV, cytotoxicity and nutritional analysis of Trianthema portulacastrum L. (Aizoaceae)

The development of antiretroviral therapy has brought a tremendous relief to the world as it minimizes mortality, reduces HIV transmission, and suppresses progression in infected patients. However, the orthodox antiretroviral therapy is faced with limitations which have necessitated a continuous search for more novel plant-based antiviral compounds, which can bypass the existing barriers created by drug resistance and target more viral proteins. Despite the edibility and enormous pharmacological benefits of T. portulacastrum, little is known about its nutrient profiles and potential use as a natural source of antiviral drug. This study focuses on the full feed analysis and anti-HIV potential of two biotypes of T. portulacastrum. Ethanolic extracts of both biotypes of T. portulacastrum (T01 and T02) had significant inhibitory effects on the level of replication of the HIV-1. Both extracts induced the inhibition of at least 50% of the HIV-1 viral load at considerably low IC50 values of 1.757 mg/mL (T01) and 1.205 mg/mL (T02) which is comparable to the AZT standard. The protein composition ranged between 8.63-22.69%; fat (1.84-4.33%); moisture (7.89-9.04%); fibre (23.84-49.98%); and carbohydrate content (38.54-70.14%). Mineral contents of tested T. portulacastrum varied considerably in different parts of the plant. Nitrogen N mineral ranged between 13.8-36.3 mg/g; sodium Na (2.0-14.0 mg/g); potassium K (14.0-82.0 mg/g); magnesium Mg (2.8-7.1 mg/g); calcium Ca (9.1-24.7 mg/g); phosphorus P (1.3-3.6 mg/g); iron Fe (193.5-984.0 ppm); zinc Zn (42.5-96.0 ppm); manganese Mn (28.5-167.5 ppm); and copper Cu (2.0-8.5 ppm). These mineral values are comparable or higher than values quoted for common vegetables, suggesting that T. portulacastrum is a nutrient-dense vegetable that could provide alternative sources of antiviral nutrients to HIV-infected individuals. Further studies are recommended to unravel key metabolites responsible for high nutrient profiles and antiretroviral effects in T. portulacastrum.

Nutrients and phytochemical density in Mesembryanthemum crystallinum L. cultivated in growing media supplemented with dosages of nitrogen fertilizer

Mesembryanthemum crystallinum L. is an annual halophyte that originated from southern Africa. However, little has been reported about factors that modulate the quantity of secondary metabolites in the plant. In this study, the twin effect of different nitrogen concentrations (0.36, 0.6, 0.8 g/L) and growing media (LECA clay, peat, vermiculite and silica sand) on plant growth, chlorophyll contents, minerals, proximate and antioxidant metabolites in hydroponically cultivated M. crystallinum was investigated. This is important to determine the dosage of N fertilizer that will optimize the bio-productivity and biosynthesis of secondary metabolites and antioxidants in M. crystallinum grown in a hydroponic system. The untreated plant (0 g/L N) was taken as the control. At the end of the experiment, optimum yields in leaf number (9.2), fresh weight (50.40 g), Ca, N, and Protein (34.04 %) were recorded in M. crystallinum grown with peat enhanced with different dosages of N-fertilizer. Likewise, chlorophyll level, dry weight, ABTS/TEAC, FRAP, ADF and NDF contents were optimized in LECA clay treated with N-fertilizer. Silica sand with 0.36 g/L dosage of nitrogen fertilizer optimized P, Mn and Zn levels, so also the moisture (9.83 % at 0.8 g/L N), fat (2.38 %, 0 g/L N) and carbohydrates (44.98 and 44.95 %). The highest ash content, Mg and Fe were recorded in the untreated vermiculite as well as polyphenols and K, at 0.6 g/L; Cu and root length (14.60 cm), at 0.8 g/L. In conclusion, different dosages of nitrogen fertilizer and growing media could enhance the growth potential, chlorophyll, phytochemicals, and nutritional properties of M. crystallinum.

Phytochemical profiling of three Amaranthus species using LC-MS/MS metabolomic approach and chemometric tools

Several Amaranthus vegetables (Amaranthaceae) have been recognized as valuable sources of minerals, vitamins, proteins, and phytonutrients, with health-promoting characteristics. In this study, three edible Amaranthus species, namely A. hybridus (AH), A. blitum (AB), and A. caudatus (AC), were chemically characterized using non-targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique. Further, multivariate chemometric analyses were conducted, including principal component analysis (PCA) and correlation-covariance plot (C-C plot). As a result, forty-one diverse compounds were identified, which varied in distribution and abundance across the investigated species. Amino acids and flavonoid glycosides were the most prevalent metabolites. Other identified compounds comprised nucleoside, chlorogenic acids, hydroxy cinnamoyl amides, and triterpenoid saponins. The most discriminant metabolites were flavonoid glycosides and hydroxy cinnamoyl amides, giving each species a chemotaxonomic identity. Advancing the chemotaxonomy of Amaranthaceae, adenosine nucleoside and N-coumaroyl-ʟ-tryptophan were first reported from this family. Isorhamnetin and tricin glycosides were uniquely identified in AC, offering useful chemotaxonomic markers for this species. Notably, AB and AH profiles shared most metabolites, yet with varying abundance. These include adenosine, nicotiflorin, dicaffeoylquinic acids, and N-trans-feruloyl-4-O-methyldopamine. However, N-coumaroyl-ʟ-tryptophan and kaempferol dirhamnoside were exclusively found in AB, separating it from AH. In conclusion, the applied analytical techniques established molecular fingerprints for the included species, identified specific biomarkers, and investigated their interconnections.

Potassium Application Enhanced Plant Growth, Mineral Composition, Proximate and Phytochemical Content in Trachyandra divaricata Kunth (Sandkool)

Wild leafy vegetables are commonly included in the diet of people in rural homesteads. Among various wild edible vegetables in South Africa, Trachyandra divaricata (Sandkool) is one of the most abundant but underutilized due to the dearth of literature on its cultivation and nutritional value. In the present study, the effect of potassium application and pruning on growth dynamics, mineral composition, and proximate and phytochemical content in T. divaricata were evaluated. Treatments consisted of three potassium concentrations (0.0072, 0.0144, and 0.0216 M) supplemented in the form of potassium sulphate (K2SO4) with four pruning levels (unpruned, 5, 10, and 15 cm) applied in each treatment. The potassium doses were added to the nutrient solution, while the control treatment was sustained and irrigated with nutrient solution only. The results revealed a significant increase in flower bud yield, height, total dry and wet weight of shoots and roots, as well as ash and neutral detergent fibre in plants irrigated with 0.0072 M of K2SO4 without pruning. Conversely, chlorophyll content and Ca were comparable among treatments, while the highest yield of Na, P, N, and Zn was recorded in treatment 100 mL of K2SO4 with 10 cm pruning. Likewise, the highest antioxidant value (Polyphenols, Flavonol and DPPH) was obtained from plants irrigated with 0.0072 M of K2SO4 with 10 cm pruning. Based on these findings, T. divaricata is a promising leafy vegetable as a minimum dose (0.0072 M) of K with moderate pruning optimised its productivity in terms of growth, biomass parameters, nutritional content, and antioxidant potential. Due to its rich nutritional value, the plant should be domesticated and studied further for its potential nutraceutical benefits.

Physical, functional and sensory properties of bitter chocolates with incorporation of high nutritional value flours

Due to the growing demand for healthy food products, the industry is seeking to incorporate inputs with high nutritional potential to traditional products. The objective of this research was to evaluate the effect of incorporating Lepidium meyenii, Chenopodium pallidicaule, Amaranthus caudatus, Sesamum indicum and Salvia hispanica flours on the physical, chemical, rheological, textural and thermal characteristics, and the degree of sensory acceptance of dark chocolate bars (65% cocoa). To this end, chocolate bars were made with the incorporation of five flours in four doses (1, 2, 3 and 4%), obtaining 20 different formulations compared with a control treatment (without flour addition). It was found that as flour incorporation levels increased, viscosity, antioxidants and particle size of the chocolates increased, but hardness and pH decreased. The addition of the flours also affected the acceptability and microstructure of the chocolate bars. The incorporation of up to 4% of the flours studied improved the degree of acceptance of the chocolates. Consequently, the incorporation of grain flours with high nutritional value can enhance the characteristics of dark chocolates, becoming a technological alternative for the chocolate industry.

Effects of Germination and Popping on the Anti-Nutritional Compounds and the Digestibility of Amaranthus hypochondriacus Seeds

Amaranth seeds, although a valuable food in Mexico, contain anti-nutritional compounds that can affect food quality. As a part of this work, the proximate composition, fatty acid profile, protein digestibility, and the effect of germination and popping of Amaranthus hypochondriacus seeds was analyzed with the aim of eliminating anti-nutritional compounds. Untreated seeds comprised of 11.35-18.8% protein and 0.27-13.39% lipids, including omega 3, 6, and 9 fatty acids such as oleic, linoleic, linolenic, and arachidonic acid. The main minerals detected were Ca+2, K+1, and Mg+2. Nevertheless in vitro studies indicate that germination significantly improved digestibility, whereby treatments aimed at reducing anti-nutritional compounds decreased lectin concentration, while significantly increasing tannins and completely eliminating trypsins and saponins.

Colorant Pigments, Nutrients, Bioactive Components, and Antiradical Potential of Danta Leaves (Amaranthus lividus)

In the Indian subcontinent, danta (stems) of underutilized amaranth are used as vegetables in different culinary dishes. At the edible stage of the danta, leaves are discarded as waste in the dustbin because they are overaged. For the first time, we assessed the colorant pigments, bioactive components, nutrients, and antiradical potential (AP) of the leaves of danta to valorize the by-product (leaf) for antioxidant, nutritional, and pharmacological uses. Leaves of danta were analyzed for proximate and element compositions, colorant pigments, bioactive constituents, AP (DPPH), and AP (ABTS+). Danta leaves had satisfactory moisture, protein, carbohydrates, and dietary fiber. The chosen danta leaves contained satisfactory magnesium, iron, calcium, potassium, manganese, copper, and zinc; adequate bioactive pigments, such as betacyanins, carotenoids, betalains, β-carotene, chlorophylls, and betaxanthins; and copious bioactive ascorbic acid, polyphenols, flavonoids, and AP. The correlation coefficient indicated that bioactive phytochemicals and colorant pigments of the selected danta leaves had good AP as assessed via ABTS+ and DPPH assays. The selected danta leaves had good ROS-scavenging potential that could indicate massive possibilities for promoting the health of the nutraceutical- and antioxidant-deficit public. The findings showed that danta leaves are a beautiful by-product for contributing as an alternate origin of antioxidants, nutrients, and bioactive compounds with pharmacological use.

Phytonutrients, Colorant Pigments, Phytochemicals, and Antioxidant Potential of Orphan Leafy Amaranthus Species

The underutilized Amaranthus leafy vegetables are a unique basis of pigments such as β-cyanins, β-xanthins, and betalains with radical scavenging capacity (RSC). They have abundant phytonutrients and antioxidant components, such as pigments, vitamins, phenolics, and flavonoids. Eight selected genotypes (four genotypes from each species) of underutilized Amaranthus leafy vegetables were evaluated for phytonutrients, pigments, vitamins, phenolics, flavonoids, and antioxidants in a randomized complete block design under ambient field conditions with three replicates. The studied traits showed a wide range of variations across eight genotypes of two species of Amaranthus leafy vegetables. The highest fat, β-xanthins, K, dietary fiber, Mg, β-cyanins, Mn, chlorophyll ab, Zn, TP, TF, betalains, chlorophyll a content, and (RSC) (DPPH) and RSC (ABTS+) were obtained from A. tricolor accessions. Conversely, the highest protein, Cu, carbohydrates, Ca, and chlorophyll b content were obtained from A. lividus accessions. The highest dry matter, carotenoids, Fe, energy, and ash were obtained from A. tricolor and A. lividus. The accession AT2 confirmed the highest vit. C and RSC (DPPH) and RSC (ABTS+); AT5 had the highest TP content; and AT12 had the highest TF content. A. tricolor accessions had high phytochemicals across the two species, such as phytopigments, vitamins, phenolics, antioxidants, and flavonoids, with considerable nutrients and protein. Hence, A. tricolor accessions can be used as high-yielding cultivars comprising ample antioxidants. The correlation study revealed that vitamin C, pigments, flavonoids, β-carotene, and phenolics demonstrated a strong RSC, and showed a substantial contribution to the antioxidant potential (AP) of A. tricolor. The investigation exposed that the accessions displayed a plentiful origin of nutritional values, phytochemicals, and AP with good quenching ability of reactive oxygen species (ROS) that provide enormous prospects for nourishing the mineral-, antioxidant-, and vitamin-threatened community.

OBTAINING OF BIOLOGICALLY ACTIVE SUBSTANCES FROM AMARANTHUS CAUDATUS L. SEEDS IN ONE TECHNOLOGICAL CYCLE

Nowadays, amaranth is a valuable multi-purpose crop, a source of a number of very important biologically active substances. The aim of this study was to develop a comprehensive scheme for obtaining fatty oil, a sum of triterpenoids and a lectin from the seeds of Amaranthus caudatus L. in one technological cycle. Two variants of the lectin and the triterpene compounds purification from amaranth seeds were tested. It was determined that extracted of triterpene compounds should be carried out after purification of the lectin from degreased seeds. The rationality of this sequence of technological operations is explained by the lability of the lectin and insolubility in water triterpene compounds from amaranth seeds. The study also presents a scheme for obtaining squalene from amaranth oil by chromatography on silica gel and proposed a more effective affinity sorbent for purification of the lectin. The use of such sorbent also opens the possibility of preserving other water-soluble substances from amaranth seeds. Physicochemical characteristics and carbohydrate specificity of the lectin are described, new data on the results of interaction of the lectin with human and animal erythrocytes are given. The obtained results are discussed in the light of complex use of raw materials.

A Systematic Review on Amaranthus-Related Research

Leafy vegetables promote reparation of energy loss due to oxidative stress, and they have the potential to alleviate hunger and malnutrition as well as other forms of metabolic imbalance ravaging the world. However, these vegetables are underutilized, despite the fact that they harbor essential minerals needed for critical cellular activities. As amaranth is one of the earliest vegetables reputed for its high nutraceutical and therapeutic value, in this study, we explored research on the Amaranthus species, and identified areas with knowledge gaps, to harness the various biological and economic potentials of the species. Relevant published documents on the plant were retrieved from the Science Citation Index Expanded accessed through the Web of Science from 2011 to 2020; while RStudio and VOSviewer were used for data analysis and visualization, respectively. Publications over the past decade (dominated by researchers from the USA, India, and China, with a collaboration index of 3.22) showed that Amaranthus research experienced steady growth. Findings from the study revealed the importance of the research and knowledge gaps in the underutilization of the vegetable. This could be helpful in identifying prominent researchers who can be supported by government funds, to address the malnutrition problem in developing countries throughout the world.

Ginger from Farmyard to Town: Nutritional and Pharmacological Applications

Ginger (Zingiber officinale) is one of the most widely used natural products consumed as a spice and medicine for treating diabetes, flatulent intestinal colic, indigestion, infertility, inflammation, insomnia, a memory booster, nausea, rheumatism, stomach ache, and urinary tract infections. To date, over 400 bioactive components, such as diarylheptanoids, gingerol analogues, phenylalkanoids, sulfonates, monoterpenoid glycosides, steroids, and terpene compounds have been derived from ginger. Increasing evidence has revealed that ginger possesses a broad range of biological activities, especially protective effects against male infertility, nausea and vomiting, analgesic, anti-diabetic, anti-inflammatory, anti-obesity, and other effects. The pharmacological activities of ginger were mainly attributed to its active phytoconstituents such as 6-gingerol, gingerdiol, gingerol, gingerdione, paradols, shogaols, sesquiterpenes, zingerone, besides other phenolics and flavonoids. In recent years, in silico molecular docking studies revealed that gingerol (6-gingerol, 8-gingerol, and 10-gingerol) and Shogaol (6-shogaol, 8-shogaol, 10-shogaol) had the best binding affinities to the receptor protein in disease conditions such as diabetes, inflammation, obesity, and SARS-CoV-2. Furthermore, some clinical trials have indicated that ginger can be consumed for alleviation of nausea and vomiting induced by surgery, pain, diabetes, obesity, inflammation, male infertility. This review provides an updated understanding of the scientific evidence on the development of ginger and its active compounds as health beneficial agents in future clinical trials.

The Impact of Salt Stress on Plant Growth, Mineral Composition, and Antioxidant Activity in Tetragonia decumbens Mill.: An Underutilized Edible Halophyte in South Africa

Climate change, expanding soil salinization, and the developing shortages of freshwater have negatively affected crop production around the world. Seawater and salinized lands represent potentially cultivable areas for edible salt-tolerant plants. In the present study, the effect of salinity stress on plant growth, mineral composition (macro-and micro-nutrients), and antioxidant activity in dune spinach (Tetragonia decumbens) were evaluated. The treatments consisted of three salt concentrations, 50, 100, and 200 mM, produced by adding NaCl to the nutrient solution. The control treatment had no NaCl but was sustained and irrigated by the nutrient solution. Results revealed a significant increase in total yield, branch production, and ferric reducing antioxidant power in plants irrigated with nutrient solution incorporated with 50 mM NaCl. Conversely, an increased level of salinity (200 mM) caused a decrease in chlorophyll content (SPAD), while the phenolic content, as well as nitrogen, phosphorus, and sodium, increased. The results of this study indicate that there is potential for brackish water cultivation of dune spinach for consumption, especially in provinces experiencing the adverse effect of drought and salinity, where seawater or underground saline water could be diluted and used as irrigation water in the production of this vegetable.

Evaluation of nutritional and elemental compositions of green and red cultivars of roselle: Hibiscus sabdariffa L

Roselle—Hibiscus sabdariffa L. leaves at different stages of growth, calyces and seeds were analyzed for nutritional and anti-nutritional factors. All the treatments contained a good but varied proportion of carbohydrate in a range of 26.93–54.13%, crude protein from 5.7 to 27.06%, crude fat 1.16–13.09%, crude fibre 15.75–36.10%, energy 631.36–1065 kJ, ash 6.08–13.74% and moisture content 6.00–9.7%. The vitamins A, C and E were also found to be present in all the treatments in a different but substantial amount. The calcium, magnesium and iron contents in all the treatments were higher than the recommended daily allowance of 1250, 350, and 15 mg for adults, while the phosphorus and sodium values in all the treatments were below 1000 and 1500 mg RDA for adults. However, the Na + /K + for all the treatments were lower than 1. The values of anti-nutrients in the samples were small except post-flowering red which had high phytate content of 21.02%, although this can be easily reduced during processes like boiling and cooking. Thus, both cultivars of roselle contain high nutritional, elemental, and vitamins compositions and small content of anti-nutrients.

Variabilities in alkaloid concentration of Sceletium tortuosum (L.) N.E. Br in response to different soilless growing media and fertigation regimes in hydroponics

This study was designed to investigate the variations in alkaloid concentrations of Sceletium tortuosum when grown in soilless mediums under different fertigation regimes and to examine the suitability of the plant for hydroponic cultivation. A mother plant obtained from Verve Dynamics (Pty) Ltd (a manufacturer and supplier of purified botanical extracts) was cultivated into three hundred plants used for this research study. Twenty treatments were evaluated with 15 sample replicates. Treatments were made up of 4 different soilless growing media, namely: pure silica sand, 50% silica sand with 50% coco-peat, 50% silica sand with 50% vermiculite, and 50% silica sand with 50% perlite. These growing media were tested in conjunction with 5 different fertigation regimes (FR). Plants grown in FR1 received aqueous nutrient solution once every week, FR2 received aqueous nutrient solution once every second week, FR3 received aqueous nutrient solution once every third week, FR4 received aqueous nutrient solution once every fourth week and FR5 received aqueous nutrient solution once every fifth week respectively. Results from this experiment showed that different soilless growing media and fertigation had varying effects on alkaloid concentrations in S. tortuosum. It was also observed that roots contained higher amounts of delta 7 mesembrenone and mesembrenone, while shoots contained higher amounts of the alkaloid mesembrine.

Suitability of Roselle-Hibiscus sabdariffa L. as Raw Material for Soft Drink Production

Consumption of conventional soft drinks has been linked with several diseases in man. This has called for the consumption of natural soft drinks such as roselle drink. Roselle-Hibiscus sabdariffa L. is the major raw material for the production of beverage called cranberry (Florida), bissap (Egypt), zobo (Nigeria), and roselle drink generally. The nutritional and phytochemical properties found in roselle make the plant useful in the preparation of some drugs and food. It has been reported that consumption of roselle drink helps to cure diseases such as high blood pressure and diabetes. The pharmacological properties of the plant are traceable to activities of flavonoid and anthocyanin which are the major antioxidants in roselle. Good aroma and colour of the drink are among the characteristics displayed by the plant. However, consumers are sometimes exposed to risks when the drink is consumed after 24 hours of preparation due to the proliferation of spoilage microorganisms in the drink. Most of these microbes thrive even at extreme temperatures. Unfortunately, some of these microorganisms are of public health importance causing diseases such as meningitis and dysentery. Researchers have revealed that roselle calyx is the major source of contamination in the drink. This paper reviews the suitability of the plant for soft drink production. It further highlights the nutrition, pharmacology, and limitations of the plant for soft drink production.

Toxicity and Antimicrobial Activities of Amaranthus caudatus L. (Amaranthaceae) Harvested From Formulated Soils at Different Growth Stages

This study examined the toxicity and antimicrobial effects of ethanol and aqueous extracts from Amaranthus caudatus grown on soils formulated from parent particles of silt, sand and clay in a glasshouse. Four different soils namely; sandy clay loam, loam, clayey loam and silty clay loam from were formulated were used for cultivation with the unfractionated soil which was the control. Crude extracts obtained from the plant shoots harvested at different growth stages were tested on some certain gram-negative and gram-positive bacteria and some fungi via agar dilution assay. The toxicity of the water and ethanol extracts was also examined via Artemia salina assay and the level of lethality was measured against Clarkson's lethality scale. All aqueous samples, as well as ethanol extracts of flowering and pre-flowering harvests of control soil tested, were non-toxic (LC50 > 1 mg/mL). At post flowering, the ethanolic extracts were highly toxic mostly in clayey loam, control, sandy-clayey loam soils (LC50 < 0.5 mg/mL). Also, antifungal effects of the plant revealed that extracts inhibited the growth of Candida albicans significantly with mild effect on Candida glabrata, Penicillium chrysogenum and Penicillium aurantiogriseum suggesting that the plant is a promising pharmacological candidate in the treatment of candidiasis. For an optimal yield of non-toxic supplement for household consumption which may also serve as pharmacological precursors, clayey loam soil is recommended for cultivation and harvesting may occur at pre-flowering or flowering stage using ethanol and water as solvents of extraction.