Plants by their genetic makeup possess an innate ability to synthesize a wide variety of phytochemicals that help them to perform their normal physiological functions and/or to protect themselves from microbial pathogens and animal herbivores. The synthesis of these phytochemicals presents the plants their natural tendency to respond to environmental stress conditions. These phytochemicals are classified either as primary or secondary metabolites. The secondary metabolites have been identified in plants as alkaloids, terpenoids, phenolics, anthraquinones, and triterpenes. These plant-based compounds are believed to have diverse medicinal properties including antioxidant properties. Plants have therefore been a potential source of antioxidants which have received a great deal of attention since increased oxidative stress has been identified as a major causative factor in the development and progression of several life-threatening diseases, including neurodegenerative and cardiovascular diseases and wound infection. Consequently, many medicinal plants have been cited and known to effect wound healing and antioxidant properties. This chapter briefly reviews antioxidant properties of medicinal plants to highlight the important roles medicinal plants play in wound healing.

Background. Abrus precatorius is used in folk medicine across Afro‐Asian regions of the world. Earlier, glucose lowering and pancreato‐protective effects of Abrus precatorius leaf extract (APLE) was confirmed experimentally in STZ/nicotinamide‐induced diabetic rats; however, the underlying mechanism of antidiabetic effect and pancreato‐protection remained unknown. Objective. This study elucidated antidiabetic mechanisms and pancreato‐protective effects of APLE in diabetic rats. Materials and Methods. APLE was prepared by ethanol/Soxhlet extraction method. Total phenols and flavonoids were quantified calorimetrically after initial phytochemical screening. Diabetes mellitus (DM) was established in adult Sprague‐Dawley rats (weighing 120–180 g) of both sexes by daily sequential injection of nicotinamide (48 mg/kg; ip) and Alloxan (120 mg/kg; ip) over a period of 7 days. Except control rats which had fasting blood glucose (FBG) of 4.60 mmol/L, rats having stable FBG (16–21 mmol/L) 7 days post‐nicotinamide/Alloxan injection were considered diabetic and were randomly reassigned to one of the following groups (model, APLE (100, 200, and 400 mg/kg, respectively; po) and metformin (300 mg/kg; po)) and treated daily for 18 days. Bodyweight and FBG were measured every 72 hours for 18 days. On day 18, rats were sacrificed under deep anesthesia; organs (kidney, liver, pancreas, and spleen) were isolated and weighed. Blood was collected for estimation of serum insulin, glucagon, and GLP‐1 using a rat‐specific ELISA kit. The pancreas was processed, sectioned, and H&E‐stained for histological examination. Effect of APLE on enzymatic activity of alpha (α)‐amylase and α‐glucosidase was assessed. Antioxidant and free radical scavenging properties of APLE were assessed using standard methods. Results. APLE dose‐dependently decreased the initial FBG by 68.67%, 31.07%, and 4.39% compared to model (4.34%) and metformin (43.63%). APLE (100 mg/kg) treatment restored weight loss relative to model. APLE increased serum insulin and GLP‐1 but decreased serum glucagon relative to model. APLE increased both the number and median crosssectional area (×10⁶μm²) of pancreatic islets compared to that of model. APLE produced concentration‐dependent inhibition of α‐amylase and α‐glucosidase relative to acarbose. APLE concentration dependently scavenged DPPH and nitric oxide (NO) radicals and demonstrated increased ferric reducing antioxidant capacity (FRAC) relative to standards. Conclusion. Antidiabetic effect of APLE is mediated through modulation of insulin and GLP‐1 inversely with glucagon, noncompetitive inhibition of α‐amylase and α‐glucosidase, free radical scavenging, and recovery of damaged/necro‐apoptosized pancreatic β‐cells.

Context: Polyscias fruticosa (L.) Harms (Araliaceae) is used as a traditional remedy for asthma in Ghana. Objective: The objective of this study is to establish the anti-asthmatic property and a possible mode of activity of an ethanol leaf extract of P. fruticosa (PFE). Materials and methods: The time (min) for pre-convulsive dyspnea, and time for recovery, after sensitization with 150 μg OVA and induction of bronchospasm with 1% acetylcholine or histamine in normal, and 100, 250, and 500 mg/kg PFE-treated Dunkin Hartley guinea pigs, were recorded. Atropine (0.1 mg), mepyramine (0.1 mg), and PFE (1 mg) effect on a contractile response of 2.0 × 10⁻² μg/ml acetylcholine and 5.8 × 10⁻² μg/ml histamine on the isolated guinea pig ileum was investigated. Cytological and histological studies were conducted using guinea pig peritoneal mast cells and mesenteric cells, respectively, to establish PFE effect on compound 48/80-induced mast cell degranulation. Results: PFE (100–500 mg/kg) prolonged the onset of pre-convulsive dyspnea by 76.1–180.2% (p ≤ 0.01–0.001), and decreased recovery time by 71.9–78.5% (p ≤ 0.01–0.001). It also enhanced percentage protection against histamine-induced bronchospasm by 15.8–80.1-fold (p ≤ 0.05–0.01), and decreased percentage recovery time 2.5–3.3-fold (p ≤ 0.05–0.01). PFE significantly inhibited (60.4 ± 8.3%) contractile responses of histamine and produced significant inhibition (56–79%: p ≤ 0.001) of mast cell degranulation. Conclusion: PFE has anti-asthmatic, antihistaminic, and mast cell stabilization effect making it useful in traditional asthma management.

Background. Despite the enrollment of new small molecules such as Sorafenib for the treatment of hepatocellular carcinoma (HCC), HCC still remains a significant contributor to cancer-related mortality and morbidity globally. Zanthoxylum zanthoxyloides is long suspected of possessing anticancer bioactive compounds that may hold the prospect of adjunctive therapy against inflammation-related cancers such as HCC. Objective. This study assessed the effects of an alkaloidal extract of the leaves of Zanthoxylum zanthoxyloides on CCl₄/olive oil (1 : 1 v/v)-induced HCC-like phenotypes in rats. Materials and Methods. Zanthoxylum zanthoxyloides alkaloidal extract (ZZAE) was prepared using Soxhlet and liquid-liquid extraction methods. Subsequently, ZZAE was characterized phytochemically. In the curative method, experimental HCC was established in adult (8–10 weeks old) male Sprague-Dawley rats weighing 150–300 g by twice-daily administration of CCl₄/olive oil (1 : 1 v/v) (2 mL/kg ip). After confirmation of experimental HCC in rats, the rats were randomly reassigned into seven (7) groups of seven (7) rats each and treated daily for 12 weeks as follows: control (normal saline, 5 ml/kg po), model (CCl₄, 5 ml/kg, ip), ZZAE (50, 100, and 200 mg/kg po), carvedilol (6.25 mg/kg po), and 20% Tween20 (1 mL/rat, po). To assess whether ZZAE has a prophylactic (preventive) effect, rats were first treated with ZZAE and later exposed to CCl₄ reconstituted in olive oil. Results. ZZAE (100 and 200 mg/kg) and carvedilol decreased tumor incidence compared to that of control. Compared to control, ZZAE (100 and 200 mg/kg) significantly ( ) improved serum GGT. Compared to control, ZZAE improved hepatohistological distortions induced by CCl₄/olive oil and also improved liver/body weight ratio. Compared to water, ZZAE arrested mitosis in the Allium cepa assay. Conclusion. ZZAE ameliorated CCl₄/olive oil-induced HCC-like phenotype in rats and demonstrated general hepatoprotective effects by improving liver and kidney function markers. This finding rationalizes the need for further studies on ZZAE as a potential source of bioactive anti-HCC compounds.

Background. Parkia clappertoniana Keay (Family: Fabaceae) (P. clappertoniana) fruit husk is commonly used in northern Ghana for wound treatment. However, this folk claim remains to be confirmed scientifically. Objective. This study investigated wound healing and antimicrobial effects of P. clappertoniana fruit husk extract (PCFHE) by using excision wound model in rats. Materials and Methods. After preparation and phytochemical analysis of PCFHE, it was reconstituted in purified water and emulsifying ointment yielding a wound healing formula (0.3, 1, and 3%). Excision wounds were established in healthy male Sprague‐Dawley rats (aged 8‐10 weeks; weighing 150–200 g). Rats were randomly assigned into six groups (model, 1% silver sulfadiazine [SSD], vehicle, and PCFHE [0.3, 1, and 3%, respectively]) and topically treated daily until complete wound healing. The endpoints (period of epithelialization, wound contraction, collagen content, erythema index, oedema index, inflammatory cell infiltration, and antimicrobial activity) were assessed for all groups. Minimum fungicidal concentration (MFC), minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time‐kill were assessed. Results. Quercetin and catechin were detected in PCFHE. Compared to model and vehicle groups, PCFHE‐treatment groups improved wound healing and antimicrobial (MBC, MFC, and MIC) endpoints. PCFHE demonstrated bacteriostatic and fungicidal effects against identified wound contaminants (Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Candida albicans). Conclusion. P. clappertoniana fruit husk possesses wound healing and antimicrobial effects in excisional wounds in rats that confirms its folk use, and the reported pharmacological properties of PCFHE are attributable to its quercetin and catechin phyto‐constituents.