Chemical Compositions, Antioxidant and Antimicrobial Activities of Essential Oils of Psidium guajava L. Leaves from Different Geographic Regions in China

Abstract

Hydrodistilled essential oils (EO) of Psidium guajava L. leaves from different regions in China were analyzed by GC and GC/MS. The samples from Guangdong Province displayed high EO yields (0.61 - 0.75%, v/w). A total of 50 components, representing over 98.00% of the EOs, were identified and semi-quantitatived. The major constituents of EOs included β-caryophyllene (17.17 - 31.38%), γ-gurjunene (9.17 - 15.22%), τ-cadinol (1.35 - 10.02%) and calamenene (2.13 - 7.80%). The terpenoids in all sample oils were dominated by sesquiterpenes hydrocarbons (70.18 - 84.35%), followed by oxygenated sesquiterpenes (9.89 - 22.19%). The similarities and differences among EOs from different samples were evaluated by hierarchical cluster analysis and principal component analysis methods. The IC values of EOs from different regions were between 18.52 - 33.72 mg/ml (DPPH) and 13.12 - 25.15 mg/ml (ABTS ). The FRAP value of EO from Guangdong Province was 7.34 - 9.13 mmol Vc/g DM, while the FRAP value of EO from Taiwan Province was 2.29 - 2.36 mmol Vc/g DM. The antimicrobial tests revealed that EO had a higher antimicrobial activity against all Gram-positive bacteria and two fungi. Moreover, EO from P. guajava leaves of Guangdong Province showed the highest antimicrobial activity. These properties can be considered in the design of industrial products and for further application in the food, pharmaceutical and cosmetic industries.

Evaluating Antitumor and Antioxidant Activities of Yellow Monascus Pigments from Monascus ruber Fermentation

“…The antioxidant activities of the yellow Monascus pigments were determined by the activities of DPPH radical scavenging and ABTS radical cation (ABTS + ) scavenging evaluated. According to the method reported by Wang et al [37], with minor modifications, 50 μL NYMPs solution at concentrations of 25, 75, 100, 500, and 1000 μg/mL were mixed with 200 μL DPPH methanol solution (600 μmol/L). The mixture was kept in the dark at room temperature for 60 min.…”

“…The freshly prepared ABTS + solution was prepared by oxidation of 7 mmol/L ABTS with 2.45 mmol/L potassium persulfate [37]. A 50 μL sample solution at concentrations of 25, 50, 75, 100, and 250 μg/mL was thoroughly mixed with 200 μL of ABTS + solution and kept at room temperature for 60 min in the dark.…”

Monoterpenes and Sesquiterpenes of Essential Oils from Psidium Species and Their Biological Properties

“…Profile II corresponded to a record oil from Cuba, rich in the sesquiterpenes of caryophyllane, acyclic, cadinane and aromadendrene types: E -caryophyllene (21.6%), E -nerolidol (l9.2%), selin-11-en-4α-ol (13.4%), viridiflorene (8.8%), α-selinene (8.3%), caryophyllene oxide (8.2%), and cedr-8(15)-en-9α-ol (7.9%) [ 52 ]. The profile III displayed compounds with caryophyllane and aromadendrene skeletons, as E -caryophyllene (24.4–36.4%) and γ-gurjunene (12.7–14.0%) corresponding to three oil records from China [ 53 ], and another from Tunisia, which was characterized by viridiflorol (36.4%) and E -caryophyllene (5.9%) [ 54 ].…”

“…Profile IV was composed by sesquiterpenes with caryophyllane, cadinane, and aromadendrene skeletons, as E -caryophyllene (17.2–25.7%), calamenene (6.6–7.8%), γ-gurjunene (9.2–9.5%), and epi -α-cadinol (6.0–10.0%) occurring in five oil records from Asia (China and Taiwan) [ 53 ]. Profile V was composed by three oil records from Brazil, belonging to caryophyllane, bisabolane, p -menthane, and acyclic sesquiterpene types, as E -caryophyllene (5.2–9.4%), β-bisabolol (9.2–19.5%), limonene (0–17.8%), 1,8-cineole (2.0–21.4%), E -nerolidol (5.0–7.4%), α-humulene (0–16.5%), β-bisabolene (0–6.3%), humulene epoxide II (0–6.0%), and α-pinene (0–23.9%) [ 55 , 56 ].…”

Karakteristik Densitas Dan Indeks Bias Minyak Atsiri Daun Jambu Kristal (Psidium Guajava) Menggunakan Metode Microwave Hydrodistillation Dengan Variabel Daya Dan Rasio Bahan : Pelarut

“…Salah satu penelitian tentang ekstraksi menggunakan metode destilasi air (konvensional) dari daun jambu selama 4 jam yang diterapkan pada bahan baku yang diperoleh di dataran Kathmandu, Nepal menghasilkan rendemen minyak atsiri sebesar 0,5% dengan pengaplikasian sifat mikrobanya [5]. Penelitian dengan bahan baku yang sama, tetapi pada daerah geografi yang berbeda yaitu pada beberapa teritorial di Cina menunjukkan bahwa ekstraksi menggunakan metode destilasi air selama 4 jam menghasilkan rendemen 0,61 -0,75% yang digunakan sebagai antioksidan dan antimikroba [6].…”