Notulae Scientia Biologicae (http://www.notulaebiologicae.ro), Issue 2, Volume 13, 2021: The papers published in this issue represent interesting novelties in different topics of life science. Among the exciting researches or reviews, we invite readers to find news about: Xenobiology: An expanded semantical review; Hog plums: Its importance, potentials and future prospects; Organic waste utilization and urban food waste composting strategies in China; Antimalarial phytochemicals as inhibitors against COVID-19 ACE2 receptor: Computational screening; Acute and sub-acute toxicity profile of methanol extract of Hura crepitans leaf on Wistar rats; Ethnopharmacological survey of medicinal plants used to treat cutaneous leishmaniasis in Ain Sekhouna, Saida, Algeria; Anti-proliferating activity of some toxic and medicinal plants used by Wancho tribe of Arunachal Pradesh, India; Apomictic development during different flower development stages in Crataegus tanacetifolia (Lam.) Pers., endemic to Turkey; Endophytic fungal isolation from Blumea axillaris: Identification and biological activity of secondary metabolites; Nutrient and metal concentrations in Nepenthes macfarlanei Hemsl. (Nepenthaceae) from a Malaysian montane forest.