________________________________________________________________________________ ResumoDiariamente volumosas quantidades de resíduos de melancia são produzidas ainda na colheita. Este estudo objetivou avaliar a produção, o rendimento e as características físico-químicas da pectina de (Citrullus lanatus) cultivar Crimson Sweet Extra através da otimização por experimento Box-Behnken. O planejamento composto central rotacional com quatro pontos axiais e três repetições no ponto central com as variáveis concentrações ácida, tempo e temperatura. A extração da pectina foi realizada com 5 g da farinha da entrecasca para 150 mL de solução de ácido cítrico, a precipitação foi realizada utilizando 150 mL de etanol. As pectinas obtidas apresentaram-se de baixa esterificação, alto teor de ácidos galacturônicos e alta pureza. Palavras-chave: Grau de esterificação. Ácido galacturônico. Resíduo agrícola. 44Rev. Agr. Acad., v.3, n.1, Jan/Fev (2020) AbstractDaily large quantities of watermelon waste are still produced at harvest. The objective of this study was to evaluate the production, yield and physicochemical characteristics of pectin (Citrullus lanatus) grow crops Crimson Sweet Extra by optimization by Box-Behnken experiment. The central rotational composite design with four axial points and three repetitions at the central point with the acid concentrations, time and temperature variables. Extraction of pectin was performed with 5 g of the starch flour to 150 mL of citric acid solution, precipitation was performed using 150 mL of ethanol. The pectins obtained were of low esterification, high content of galacturonic acids and high purity.

Bauhinia rufa is one of the species found inhabiting the Cerrado domain. Annually this plant species presents flowering with a light sweet aroma. The objective of this work was to evaluate the chemical profile and antifungal activity of the essential oil of B. rufa flowers on Sclerotinia sclerotiorum, Coletotrichum gloeosporioides and Aspergillus flavus. Flowers were collected in the early hours of the morning, being sent to the laboratory for extraction and yield of essential oil by the Clevenger-type system. The chemical profile of the essential oil was obtained by gas chromatography with mass detector (GC-MS), and for antifungal activity, sequences of concentrations 100, 50, 25, 12.5; 6.25; 3.13 and 1.56 µL mL-1 on strains of S. sclerotiorum, C. gloeosporioides and A. flavus. The essential oil of B. rufa showed a yield of 0.05%, 28 compounds identified, the majority being Myrcene (8.27%), O-Cymene (31.14%), 1,2-dimethyl-4-ethyl-benzene (13.08%), Trans-Pinocarveol (12.55%) and Kryptone with (8.94%). The antifungal activity showed the best results for S. sclerotiorum and C. gloeosporioides where they exhibited fungistatic activity between 100 and 54.84% at all concentrations. For A. flavus, the best inhibition concentrations were observed between 100 to 25 µL-1 with 100%, and in the lowest concentrations of 12.5 and 6.25 µL-1 with 40.55 and 10.08%, no inhibition was observed at concentrations 3.13 and 1.56 µL-1. The essential oil of B. rufa showed richness in chemical compounds and effective fungicidal action.