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Annually, significant crop losses are reported due to diseases caused by phytopathogens. Most subsistence farmers cannot afford the high cost of chemical treatments thereby resulting in the increasing dependence on plant extracts to manage crop diseases. In this study, we documented plants used for the management of cabbage and spinach diseases in OR Tambo Municipality, Eastern Cape Province. An ethnobotanical survey using semi-structured questionnaires was used to document plants and plant parts used by the subsistence farmers in managing cabbage and spinach diseases. Semi-structured questionnaires were administered to 41 consenting subsistence farmers from November to December in 2021, using snowball sampling. The collected data were subjected to descriptive statistical and ethnobotanical analyses. A total of 17 plants belonging to 10 families were identified by the participants as being used in mitigating cabbage and spinach diseases. Tulbaghia violacea , Aloe ferox , and Capsicum annuum had the highest use value of 0.32 each, whereas Tulbaghia violacea had the highest relative frequency of citation of 0.39. This current study revealed the importance of plants in managing crop diseases in local communities. It provides baseline data for future pharmacological evaluations in authenticating the efficacies of the identified plants in managing crop diseases.

Ethnopharmacological Relevance: Hypoxis hemerocallidea (commonly known as African Potato) is popular in African traditional medicine. It is used in the management of diverse ailments including burns, wounds and skin-related diseases., Aim of the Study: The current study investigated the antimicrobial effects of Hypoxis hemerocallidea against six microorganisms associated with skin diseases. In addition, the antioxidant activity, phytochemical profiles and cytotoxicity of the bulb extracts were evaluated., Materials and Methods: The antimicrobial activity of 50% methanol (MeOH) and petroleum ether (PE) extracts of Hypoxis hemerocallidea bulbs was tested against two bacterial and four fungal strains implicated in causing opportunistic skin-related diseases. Antioxidant potential of the extract was investigated via the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging assay and β-carotene linoleic acid model. Phytochemical profiling of the 50% MeOH extract of Hypoxis hemerocallidea was done using spectrophotometric assay and Gas Chromatography-Mass Spectrometry (GC-MS). The extracts were also evaluated for cytotoxicity against African green monkey Vero kidney cell lines based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay., Results: Both 50% MeOH and PE extracts showed considerable inhibitory effects against all six microorganisms. The extracts were potent against Shigella flexneri and Trichophyton tonsurans with minimum inhibitory concentration (MIC) values less than 1 mg/ml. However, there was relatively poor antifungal activity against the other fungal strains. In the DPPH assay, the MeOH extract of the bulb had an EC 50 of 29.8 μg/ml while 76.91% antioxidant activity was observed in the β-carotene-linoleic acid model. The extract contained total phenolics (41 mg GAE/g) and flavonoids (10 mg CE/g). The GC-MS analysis of Hypoxis hemerocallidea bulb revealed 29 and 160 bioactive compounds for 50% MeOH and PE extracts, respectively. Based on the cytotoxicity, Hypoxis hemerocallidea had LC 50 value of 210.9 ± 18.4 and 95.5 ± 13.3 μg/ml for PE and MeOH extracts, respectively., Conclusions: The bulb extracts of Hypoxis hemerocallidea exhibited good antimicrobial and antioxidant activities, which could be attributed to the presence of phenolics, flavonoids and the other bioactive compounds identified through GC-MS, making it a potentially effective cosmetic plant. These findings also account for the multi-pharmacological use of Hypoxis hemerocallidea in traditional medicine, especially related to skin diseases. The plant extracts can be considered as safe based on their LC 50 values (< 20 μg/ml). However, other form of cytotoxicity studies need to be carried out on Hypoxis hemerocallidea, as well as in vivo tests, to confirm its safety and efficacy as a treatment for skin-related diseases., (Copyright © 2019 Elsevier B.V. All rights reserved.)