Antioxidant and Antibacterial Activities of Four Underutilized Fruits of Bangladesh

Antioxidant and antibacterial activities of four underutilized fruits namely Jujube (Ziziphus mauritiana Lam.), Olive (Elaeocarpus serratus L.), Roselle (Hibiscus sabdariffa L.), and Taikor (Garcinia pedunculata Roxb.) commonly found in Bangladesh were evaluated. The highest total phenolic content (685.08 ± 27.65 mg GAE/100 ml) and total flavonoid content (148.18 ± 0.40 mg QE/100 ml) were found in Taikor extract, which compliance with its highest DPPH scavenging activity and antibacterial properties. It exerted a significantly higher (p ≤ 0.05) zone of inhibition against Escerichia coli, Staphylococcus spp. and Pseudomonas spp. than the other experimented fruit extracts. The antioxidant activity was found as Taikor (43.15 ± 1.61%)> Roselle (33.07 ± 1.61%) > Olive (28.68 ± 0.78%) > Jujube (24.81 ± 1.34%). Bacillus spp. are found to be more susceptible to the experimented sample extracts. Fruit samples studied may be utilized as potential sources of natural antioxidants and antibacterial compounds, and their extracts may be used as natural biopreservatives to extend the shelf life of foodstuffs. Bangladesh J. Bot. 50(4): 1035-1039, 2021 (December)

Formulation of herbal cream based on Ziziphus Mauritiana leaves extract and evaluation on physicochemical properties

Plant derived substances and herbal medicines have recently attracted the great interest towards their versatile application, as medicinal plants used in traditional and modern medicine. The aim of the current study was to investigate the antioxidant activity of Ziziphus mauritiana leaves extract followed with the formulation of herbal creams based on ZM methanolic extract then evaluate the physical characteristic and stability of the creams. After the methanolic extract was obtained by using Soxhlet extraction, the extract was assessed for antioxidant activity by using stable 2,2- Diphenyl-1-picrylhydrazyl (DPPH) which showed the IC50 value of the ZM extract is 10.57 µg/ml, while IC50 value for ascorbic acid is 4.19 µg/ml. Four formulations of water in oil (w/o) emulsion based cream was formulated based on Ziziphus mauritiana leaves extract which are F1, F2, F3 and F4. Several physical properties were evaluated such as organoleptic, pH, viscosity, homogeneity, washability and emmolliency which proved that all formulations have good homogeneity, non greasy and under suitable pH and viscosity. Based on thermal stability test (45 °C ± 70 % RH, for 48 hours), it showed that F4 is not stable at high temperature compared to other formulations. Therefore, the present study indicated that the Ziziphus mauritiana leaves extract has great potential for personal care product development.

First Report of Colletotrichum fructicola Causing Anthracnose on Indian Jujube (Ziziphus mauritiana) in Taiwan

Ziziphus mauritiana Lamarck known as Indian jujube is one of the most popular and delicious fruit crops in Taiwan. This crop is mainly planted in southern Taiwan and their fruit are harvested for providing fresh fruit. In March 2015, an anthracnose-like disease was observed on Indian jujube fruit (cv. Candied date) planted in an orchard in Yanchao District (22°46'33" N, 120°21'37" E) in Kaohsiung City. The disease was quickly distributed around the orchard after rain and caused great loss (around 40% of fruit infected). The diseased fruit would completely rot and lose its market value. Symptoms could be observed on all the developmental stages of fruit. On ripe fruit, symptoms were round, brown, water-soaked lesions covered with salmon-colored spore masses. Four fungal isolates from diseased fruit in the same orchard were collected by single spore isolation with hand-made glass needle. They were grown on potato dextrose agar (PDA) at 24 to 28°C with diffused light. All four strains produced white to gray, aerial, and cottony mycelia scattered with abundant salmon-colored conidial mass on the center of the colony on PDA. The conidia were hyaline, single celled, round cylindrical on both ends, thin walled, and the contents guttulate. The sizes of conidia were 15.2 (17.5 to 13.0) × 5.0 (5.5 to 4.5) μm (length/width ratio = 3.03, n = 40). DNA was isolated from JC1 and used for amplification of partial sequences of the internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin (ACT), β-tubulin 2 (TUB2), chitin synthase 1 (CHS-1), manganese-superoxide dismutase (SOD2) and the intergenic region of apn2 and MAT1-2-1 gene (ApMat) genes (Silva et al. 2012; Weir et al. 2012). A BLAST search against the NCBI database revealed that JC1 gene sequences [GenBank accession nos. MT197188 (ITS), MT199871 (GAPDH), MT199872 (ACT), MT199870 (TUB2), MT815918 (CHS-1), MT815919 (SOD2) and MT221653 (ApMat)] displayed 100.0, 100.0, 99.1, 100.0, 99.7, 99.5 and 99.8% nucleotide identity to the respective gene sequences of Colletotrichum fructicola ICMP 18581 (JX010165, JX010033, FJ907426, JX010405, JX009866, JX010327, and JQ807838). Conidial suspension (1 × 106 conidia/mL) was prepared from JC1 isolate of C. fructicola and inoculated by spraying onto detached, ripe, healthy, non-wounded and surface-disinfected jujube fruit (cv. Candied date, n = 4). Four control fruit were sprayed with sterile water. Fruit were kept in a moist chamber (greater than 90% relative humidity, 24 to 28°C) for 24 h and maintained in the lab for additional 5 days. The inoculated fruit initially showed small light-colored spots in 5 to 7 days, which eventually developed into brown, sunken, water-soaked lesions 8 to10 days after inoculation, similar to the symptoms in the orchard. C. fructicola was re-isolated from symptomatic fruit showing similar morphological characteristics to those collected from the field, thus fulfilling Koch’s postulates. No symptom was observed on fruit treated with water and no pathogen was re-isolated. The experiment was performed twice. The JC1 isolate of C. fructicola with the identification number BCRC FU31437 has been deposited at Taiwan Bioresource Collection and Research Center. This pathogen has been found in many plant species in various countries (Weir et al. 2012). To our knowledge, this is the first report of C. fructicola causing Indian jujube fruit anthracnose in Taiwan and worldwide.

Activated Carbons derived by Phosphoric acid Activation of Agricultural waste and their Adsorption of Methylene Blue

Agricultural wastes can be considered as suitable raw materials for activated carbon production, as activated carbon is considered as an economical adsorption material. Seeds from biomass of Ziziphus mauritiana Lam, grown in Algerian have been valorized for activated carbon production by the phosphoric acid, activation method with pyrolysis temperatures of 400, 500 and 600 °C. The effect of changes in pyrolysis temperatures on the yield and quality of the prepared activated carbon was studied. The obtained activated carbons were characterized by FT-IR and MB adsorption, a good yield of 38,625 %, a high BET surface area of 915,58 m2/g. The removal rate of methylene blue was strongly influenced by contact time, adsorbent mass and pH. An excellent removal % of methylene blue (MB) was obtained at the preferred temperature of 500 °C (AC 500).

Phytochemical Screening and Antimicrobial Activity of Ziziphus mauritiana Lam. And Ziziphus mucronate Lam. Extracts

The objective of this study was to determine the phytochemical profile and antimicrobial activity of leaf and bark extracts of Ziziphus mauritiana and Ziziphus mucronata. For this purpose, an extraction by maceration using ethanol was carried out and the extracts were subjected to antibacterial activity assessment through qualitative and quantitative approaches. The qualitative tests were performed using agar well diffusion method while for quantitative tests minimal inhibitory, bactericidal and fungicidal concentration (MIC, MBC or MFC) were used determined through microdilution in microplates method. The antimicrobial mechanisms such as cell lysis and action on the proton pump of the extracts were also studied. The highest extraction yield was obtained with the Z. mauritiana leaf extract (28.8%). In addition, the highest contents of polyphenols (256.6 mg GEA/g DM) and flavonoids (165.2 mg CE/g DM) were obtained with the bark of Z. mucronata. The bark extracts of Z. mauritiana exhibited highest antibacterial activity (36.7 mm on Staphylococcus aureus) while, Z. mucronata extracts are more active on fungi, with the highest activity on Candida albicans (26.7 mm). The antimicrobial activity of the extract increases with the concentration and, regarding the MBC/MIC and MFC/MIC ratio, the extracts showed bacteriostatic activity on the different bacteria and fungi and the possible mechanism included an activity on the proton pump. The bark and leaf extracts of Z. mauritiana and Z. mucronata could be used in traditional medicine to treat infections due to these multiple pathogens.

Identification of marker-trait associated SNPs for fruit weight and plant height in a wild and domesticated jujube fruit tree (Ziziphus spp.) collection using genotyping-by-sequencing

Ziziphus are economically and nutritionally important fruiting plants that were domesticated in China around 7000 years ago. We identified genetic diversity in 141 accessions of four, different species collected in Pakistan and in China, including wild species of Ziziphus mauritiana, Z. nummularia and Z. oxyphllya, and both wild and domesticated Z. jujuba Mill. Population structure, phylogenetic analysis and principal coordinates analysis based on 10,889 high-quality SNPs derived from genotyping-by-sequencing indicated that the accessions clustered into two major groups. The wild Pakistani Z. jujuba and Z. nummularia exhibited higher genetic diversity and polymorphic information content (0.37 and 0.23 respectively) than other species. We further conducted a genome-wide association study and discovered six highly significant marker-trait associations for fruit weight and plant height in this population. Our study provides important information for future breeding of Ziziphus species.

PENGARUH METODE PENGERINGAN DAN PERSENTASE TEH KERING TERHADAP KARAKTERISTIK SEDUHAN TEH DAUN BIDARA (Ziziphus mauritiana L.)

Bidara merupakan tanaman tradisonal yang daunnya mengandung tinggi polifenol sehingga berpotensi untuk dikembangkan menjadi produk teh herbal. Pengeringan daun bidara sangat berpengaruh terhadap kualitas rasa, warna, dan aroma teh. Penelitian ini bertujuan untuk mengkaji pengaruh – pengaruh yang dapat ditimbulkan dari metode pengeringan dan persentase teh kering terhadap karakteristik sampel seduhan teh bidara yang dibuat pada penelitian ini. Desain penelitian digunakan RAKF 2 faktor. Faktor pertama meliputi metode pengeringan yang sering digunakan dalam pengeringan teh yaitu pengeringan kabinet, sangrai, dan sinar matahari. Faktor 2 meliputi persentase penggunaan teh kering yaitu 1%, 3%, dan 5% dengan masing-masing 3 kali ulangan. Respon yang diuji meliputi warna, pH, fenol, flavonoid, aktivitas antioksidan, tanin, dan uji organoleptik yang dilakukan dengan uji hedonik. Penelitian ini menunjukkan bahwa teh daun bidara terbaik dihasilkan dari pengeringan sinar matahari dengan presentase penggunaan teh kering sebesar 5% dengan nilai fenol, flavonoid, tanin, antioksidan, dan skor hedonik paling optimal.