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Abstract Terpenoids from natural plant sources are valuable for their diverse biological activities that have important roles in the medical and agrochemical industries. In this study, we assessed the antioxidant, antifungal, and aphicidal activities of a mixture of spinasterol and 22,23-dihydrospinasterol from the leaves of Citrullus colocynthis. We used 1,1-diphenyl-2-picrylhydrazyl (DPPH) to assess antioxidant activity, and we measured antifungal activity using mycelium growth inhibition assays with three pathogenic fungi, Magnaporthe grisea, Rhizoctonia solani, and Phytophthora infestans. Aphicidal activity against adults of Myzus persicae was determined using in vitro and in vivo assays. Spinasterol and 22,23-dihydrospinasterol exhibited moderate antioxidant activity, even at lower concentrations: 19.98% at 0.78 µg mL−1, 31.52% at 3.0 µg mL−1, 36.61% at 12.5 µg mL−1, and 49.76% at 50 µg mL−1. Spinasterol and 22,23-dihydrospinasterol showed reasonable levels of fungicidal activity toward R. solani and M. grisea, with EC50 values of 129.5 and 206.1 µg mL−1 , respectively. The positive controls boscalid and carbendazim were highly effective against all fungi except boscalid for M. grisea (EC50 = 868 µg mL−1) and carbendazim for P. infestans (EC50 = 8721 µg mL−1). Significant insecticidal activity was observed in both residual and greenhouse assays, with LC50 values of 42.46, 54.86, and 180.9 µg mL−1 and 32.71, 42.46, and 173.8 µg mL−1 at 72, 48, and 24 h, respectively. The antioxidant activity of spinasterol and 22,23-dihydrospinasterol was strongly positively correlated with their antifungal and insecticidal activity. Spinasterol and 22,23-dihydrospinasterol therefore show good antioxidant and aphicidal activity with moderate fungicidal activity, making them suitable candidates for an alternative to synthetic agents.

Abstract Climate change is among the greatest drivers of biodiversity loss, threatening up to 15–30% of described species by the end of the twenty-first century. We estimated the current suitable habitat and forecasted future distribution ranges of Indian pangolin (Manis crassicaudata) under climate change scenarios. We collected occurrence records of Indian pangolin using burrow counts, remote camera records and previously published literature in Pakistan during 2021–2023. We downloaded bioclimatic data for current (1970–2000) and future (2041–2060, 2061–2080, 2081–2100) climate scenarios from the WorldClim database using the Hadley Global Environment Model (HadGEM3-GC31-LL). We used MaxEnt software to predict current and future distributions of Indian pangolin, then computed the amount of habitat lost, gained, and unchanged across periods. We obtained 560 Indian pangolin occurrences overall, 175 during the study, and 385 from our literature search. Model accuracy was very good (AUC = 0.885, TSS = 0.695), and jackknife tests of variable importance showed that the contribution of annual mean temperature (bio1) was greatest (33.4%), followed by the mean temperature of the coldest quarter (bio-12, 29.3%), temperature seasonality (bio 4, 25.9%), and precipitation seasonality (bio 15, 11.5%). The maxent model predicted that during the current time period (1970–2000) highly suitable habitat for Indian pangolin was (7270 km2, 2.2%), followed by moderately suitable (12,418 km2, 3.7%), less suitable (49,846 km2, 14.8%), and unsuitable habitat (268,355 km2, 79.4%). Highly suitable habitat decreased in the western part of the study area under most SSPs and in the central parts it declined under all SSPs and in future time periods. The predicted loss in the suitable habitat of the Indian pangolin was greatest (26.97%) under SSP 585 followed by SSP 126 (23.67%) during the time 2061–2080. The gain in suitable habitat of Indian pangolin was less than that of losses on average which ranged between 1.91 and 13.11% under all SSPs during all time periods. While the stable habitat of the Indian pangolin ranged between 64.60 and 83.85% under all SSPs during all time periods. Our study provides the current and future habitat ranges of Indian pangolin in the face of a changing climate. The findings of our study could be helpful for policymakers to set up conservation strategies for Indian pangolin in Pakistan.