Phytochemical and Nutritional Quality Changes During Irrigation and Postharvest Processing of the Underutilized Vegetable African Nightshade

Exploring biodiversity and ethnobotanical significance of Solanum species in Uzbekistan: unveiling the cultural wealth and ethnopharmacological uses

Despite its millennial existence and empirical documentation, the ethnological knowledge of herbs is a more recent phenomenon. The knowledge of their historical uses as food, medicine, source of income and small-scale businesses, and the sociological impacts are threatened due to the slow ethnobotanical research drive. Species of the genus Solanum have long been extensively used in folk medicine to treat various illnesses of humans since the dawn of civilization. All data were systematically obtained from papers, monographs, and books written in Uzbek, Russian, and English through various scientific online databases, including Google, Google Scholar, PubMed, Scopus, Semantic Scholar, Science Direct, and Web of Science using specific keywords focused on eight Solanum species. Eight native and non-native Solanum species as S. dulcamara L., S. lycopersicum L., S. melongena L., S. nigrum L., S. rostratum Dunal., S. sisymbriifolium Lam., S. tuberosum L., and S. villosum Mill. have been recorded in Uzbekistan of Central Asia. In this article we presented recently obtained data on the diversity, morphological characteristics, global distribution, habitat, population status, phenology, reproduction, pharmacology and phytochemistry of these Solanum species in Uzbekistan. Furthermore, relying on a combination of literature reviews and analyses from various scientific papers, we focus on food consumption coupled with global ethnobotanical and ethnopharmacological uses in human diseases of the Solanum species growing in Uzbekistan. Since the dawn of civilization, these eight cultivated and non-cultivated species of Solanum have provided sustainable resources of medicinal plants in Uzbekistan to prevent and treat various human diseases. Based on the collected data, it was shown that Solanum species have not been studied ethnobotanically and ethnomedicinally in Uzbekistan and it is necessary to conduct phytochemical and biotechnological research on them in the future. Traditional uses and scientific evaluation of Solanum indicate that S. nigrum, S. sisymbriifolium and S. tuberosum are one of the most widely used species in some parts of the world. Although considerable progress has been made to comprehend the chemical and biological properties of S. nigrum and S. tuberosum species, more research on the pharmacology and toxicology of these species is needed to ensure the safety, efficacy, and quality of their biologically active extracts and isolated bioactive compounds. Additionally, conducting additional research on the structure-activity relationship of certain isolated phytochemicals has the potential to enhance their biological efficacy and advance the scientific utilization of traditional applications of Solanum taxa.

Effects of Different Ripening Stages on the Content of the Mineral Elements and Vitamin C of the Fruit Extracts of Solanum Species: S. melanocerasum, S. nigrum, S. villosum, and S. retroflexum

Studies on the mineral and vitamin C contents of different species and ripening stages of Solanum fruits are very limited. The aim of the research was to evaluate the content of the mineral elements and vitamin C of four different Solanum species (S. melanocerasum-SM, S. nigrum-SN, S. villosum-SV and S. retroflexum-SR), and three ripening stages. The mineral composition of Solanum fruits was detected using a CEM MARS 6® (Matthews, NC, USA) digestion system outfitted with a 100 mL Teflon vessel, by microwave-assisted extraction (MAE). In total, eleven mineral elements were detected (K, Ca, Mg, P, Fe, Na, Cu, B, Mn, Al, and Zn). Vitamin C content was assessed by a spectrophotometric method. Depending on the ripening stage/species, content of microelements ranged from 756.48 mg kg-1 DW in SV fruits at ripening stage III, to 211.12 mg kg-1 DW in SM fruits at ripening stage III. The dominant microelement was Fe. The total content of macroelements in Solanum fruits ranged from 26,104.95 mg kg-1 DW in SV fruits at ripening stage II to 67,035.23 mg kg-1 DW in SR fruits at ripening stage I. The dominant macroelement was K. The data from two experimental years showed that the significantly highest content of vitamin C was in SM fruits and ranged from 48.15 mg 100 g-1 at ripening stage I to 45.10 mg 100 g-1 at ripening stage III.

Hibiscus sabdariffa calyx protect against oxidative stress and aluminium chloride-induced neurotoxicity in the brain of experimental rats

We evaluated the antioxidant and neuroprotective potentials of extracts of Hibiscus sabdariffa calyx in Wistar albino male rats injected intraperitoneally with aluminium chloride at a dose of 7 mg/kg/day. Phytochemical screening of H. sabdariffa calyx show that coumarin glycosides and steroid were absent after drying at 50 ^oC. At 30 ^oC, there were significant (p < 0.05) highest amounts of phenols, flavonoids, alkaloids, tannin, and saponin. The extracts showed significantly (p < 0.05) high dose-dependent antioxidant activities. MDA significantly (p < 0.05) increased, while GSH, GPX, SOD, CAT activities significantly (p < 0.05) decreased in the brain of the experimental rats induced with AlCl₃, while treatment with the extracts reversed these effects to a relatively normal level. At doses of 500 and 1000 mg/kg body weight, the extracts of the calyx dried at 30 ^oC exhibited the highest capacity to increase the activities of GSH and GPx. Also, AlCl₃ caused significant increases (p < 0.05) in the percentage inhibition of acetylcholinesterase and butyrylcholinesterase activities, and a significantly (p < 0.05) lower protein levels in the brain of the test rats, while treatment with the extracts, at low and high doses, significantly (p < 0.05) reversed these effects in the rat brain to near normal.H. sabdariffa exhibited a good potential to protect against oxidative stress and neurotoxicity.

Nutritional, health benefits and toxicity of underutilized garden cress seeds and its functional food products: a review

Garden cress seed is a potential source of macro and micronutrients including essential fatty acids and amino acids as well as minerals such as iron, potassium, calcium and phosphorus. The seed also provides appreciable amount of health-protective bioactive compounds used to treat diabetes, hypercholesterolemia, bone fracture, asthma, constipation and some forms of cancer. Besides,, it is used to develop functional foods of therapeutic value in food manufacturing industries and traditional food preparations. Even though, it is known for its superior health benefits, provision of essential nutrients, and wider application in functional food development it is among the most underutilized crop in the world. Additionally, majority of studies conducted on garden cress seeds are mainly animal trials and hence needs to conduct studies on human. Therefore, the aim of this review paper is to provide up to date research evidence on the nutrient composition and therapeutic use of underutilized garden cress seeds and its functional food products, promising for the prevention of non-communicable and communicable diseases.

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Effect of lactic acid fermentation on the nutritional quality and consumer acceptability of African nightshade

African nightshade (ANS) is among many underexploited and neglected indigenous vegetables. This study assessed the effect of lactic acid fermentation (LAF) on nutritional and sensory quality in Solanum villosum (Sv) and Solanum scabrum (Ss). Spontaneously fermented (SF) and controlled fermented (CF) conditions using Lactobacillus plantarum LP90 and Leuconostoc mesenteroides LM58 were employed for 15 days and 120 h. From the fermented pickles, relish products were prepared using cooking oil and a variety of spices. The relish products were subjected to a consumer acceptability test. Results show a significant drop in pH to <3.5, increasing titratable acidity (TTA) to around 0.6 after 120 h and 15 days of CF and SF, respectively. LAF resulted in a 2.6-5 and 1.6-4.8-fold significant rise in β-carotene in pickles and their relish products. All pickles and relish products exhibited a significant decrease (p < .05) in vitamin C by 88.33%-95.90%. LAF significantly reduced total phenolic (26%- 43%) and Chlorophyll (16.45%-39.25%). On the other hand, LAF showed improvement in minerals content (P, Ca, Fe, and Zn) and reduction of tannin (76.27%-92.88%) and oxalate (77.33%-90%) levels. LAF relish products were highly preferred by the consumers, with S. villosum controlled fermented relish (SvCFR) leading. All fermented relishes were stable at ambient (27°C) and refrigeration (4°C) temperatures after 6 months of storage. Generally, LAF is an effective method for ANS preservation, with improved nutritional quality and safety. LAF can therefore be recommended to small-scale farmers, processors, and households for ANS preservation. Ultimately, this method enhances the nutrition and sensory quality, safety, and livelihood.

High Value-Added Application of Two Renewable Sources as Healthy Food: The Nutritional Properties, Chemical Compositions, Antioxidant, and Antiinflammatory Activities of the Stalks of Rheum officinale Baill. and Rheum tanguticum Maxim. ex Regel

Rhubarb plants (Rheum officinale and R. tanguticum) have edible stalks. In this work, we aimed to compare the nutritional properties, chemical compositions, and bioactivities of R. officinale (SRO) and R. tanguticum (SRT) stalks and to analyze the composition–function relationship. Results showed that the two stalks were good sources of fiber, as well as minerals. They contained abundant essential amino acids and essential fatty acids to regulate the immunity and prevent some chronic diseases; the contents of polyunsaturated fatty acids were 2,244.32 mg/100 g and 2,844.69 mg/100 g, respectively. The antioxidant activity were also proved. Metabolomics showed that SRO and SRT contained abundant phenolic acids. Due to the higher concentrations of flavones, SRT has better antiinflammatory activities than SRO by inhibiting NF-κB signaling pathway. Rhubarb stalks exhibited good safety in acute toxicity and cytotoxicity tests. This work indicated that the two stalks have nutritional value, safety, and bioactivities, and could be used as sources of nutritional ingredients for regulating the immunity of body in food industry.

Critical stages for post-harvest losses and nutrition outcomes in the value chains of bush beans and nightshade in Uganda

The reduction of post-harvest losses (PHLs) has been identified as a key pathway to food and nutrition security in sub-Saharan Africa. However, despite policy prioritisation, knowledge about the severity of PHLs remains scant, especially when it comes to nutrient-dense crops such as African nightshade and bush beans. Therefore, this paper identifies loss hotspots, causes and effects throughout the value chains of nightshade and bush beans in eastern Uganda. Primary data collected following the Informal Food Loss Assessment Method, combined with small-scale load tracking and secondary data, allows for an analysis of physical, economic, quality, and nutritional losses throughout the value chains of both crops. Results show that in the bush bean value chain, severe physical and quality losses occur during post-harvest handling by farmers, leading to high economic losses at this stage of the chain. Nutritional losses are not expected to be significant in the bush bean value chain. By contrast, due to the shortness of the nightshade value chain, where produce is moved from harvest to consumption within one or two days, physical losses in most parts of the chain are relatively minor. Only at consumption stage, high physical losses occur. This is also the stage where economic losses and potential nutritional losses are most pronounced. The results of this study offer a deeper understanding of the value chain dynamics of bush beans and nightshade, including underlying gender relations, and identify concrete loss hotspots, upon which further research and practical interventions can build.

African nightshades (Solanum nigrum complex): The potential contribution to human nutrition and livelihoods in sub-Saharan Africa

Achieving zero hunger in sub-Saharan Africa (SSA) without minimizing postharvest losses of agricultural products is impossible. Therefore, a holistic approach is vital to end hunger, simultaneously improving food security, diversity, and livelihoods. This review focuses on the African nightshades (ANS) Solanum spp. contribution to improving food and nutrition security in SSA. Different parts of ANS are utilized as food and medicine; however, pests and diseases hinder ANS utilization. African nightshade is rich in micronutrients such as β-carotene, vitamins C and E, minerals (iron, calcium, and zinc), and dietary fiber. The leaves contain a high amount of nutrients than the berries. Proper utilization of ANS can contribute to ending hidden hunger, mainly in children and pregnant women. Literature shows that ANS contains antinutritional factors such as oxalate, phytate, nitrate, and alkaloids; however, their quantities are low to cause potential health effects. Several improved varieties with high yields, rich in nutrients, and low alkaloids have been developed in SSA. Various processing and preservation techniques such as cooking, drying, and fermentation are feasible techniques for value addition on ANS in SSA; moreover, most societies are yet to adopt them effectively. Furthermore, promoting value addition and commercialization of ANS is of importance and can create more jobs. Therefore, this review provides an overview of ANS production and challenges that hinder their utilization, possible solutions, and future research suggestions. This review concludes that ANS is an essential nutritious leafy vegetable for improving nutrition and livelihoods in SSA.