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This manuscript focuses on the development of Fruit Storage Chamber (FSC) equipped with nano-TiO2 and its modular prototype to improve the value of bamboo-based FSC by its photocatalytic and feasibility aspects. Its effects on fruit shelf life and ripening-related gene expression were studied. Cavendish bananas were stored in FSC equipped with nano-TiO2 and modular FSC for treatments. Relative expression level of ethylene biosynthesis-related (MaACS1, MaACO1) and polyphenol oxidase (MaPPO4, MaPPO5) genes were examined. The dynamics of ripening variables throughout the storage period were illustrated in regression lines, followed with hypothesis testing. Banana quantity showed no significant changes upon storage in FSC equipped with nano-TiO2. Physical appearance indicated a ripening delay of up to two days on nano-TiO2 treatments compared to control. Ethylene production rate and ethylene related gene expression were not significantly altered. Browning index was more maintained in nano-TiO2 treated samples, supported by the observation of slower increase of MaPPO4 and MaPPO5 relative expressions compared to control. The findings highlight the suppression of fruit ripening related gene expression and the maintenance of fruit quality in treated samples compared to control, indicating the potential use of nano-TiO2 to prolong banana shelf life. [ABSTRACT FROM AUTHOR]

Bananas are one of the most popular fruits, and their production generates significant agricultural waste. Banana pseudostems, a by-product of the banana industry, are being investigated as a renewable and biodegradable alternative to synthetic food packaging materials. However, these pseudostems have the potential to harbor harmful bacteria due to their natural fiber composition. Therefore, this study analyzes the effect of beeswax coating on the microbial communities in banana pseudostems. The microbial community is analyzed through a metagenomics approach that targets the 16S rRNA gene of the Saba banana (Musa × paradisiaca) pseudostem. Two experimental conditions were considered: pseudostem with beeswax coating and pseudostem without beeswax coating. The findings indicate that the microbial communities in all samples are primarily composed of the phyla Proteobacteria, Cyanobacteria, and Firmicutes. The dominant species found in uncoated banana pseudostem is Pantoea sp. At-9b, Escherichia coli, Synechococcus sp. JA-3-3-Ab, Pantoea vagans, and Klebsiella pneumoniae. The dominant species found in beeswax-coated banana pseudostem is Synechococcus sp. JA-3-3-Ab, Pseudanabaena sp. PCC 7367, Chroococcidiopsis thermalis, Priestia megaterium, and Ammonifex degensii. The Chao1, Shannon, Simpson, and Equitability indices indicate that the species richness, diversity, and evenness in the uncoated banana pseudostem are higher than in the beeswax-coated banana pseudostem. The degree of similarity between bacterial populations found in uncoated banana pseudostem and beeswax-coated banana pseudostem is around 53.9%. [ABSTRACT FROM AUTHOR]

3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR) enzyme plays an important role in the biosynthesis of diterpene lactones such as andrographolide, a specialized metabolite that is widely used as a therapeutic agent. This study aimed to enhance the content of andrographolide through the overexpression of 3-hydroxy-3-methylglutaryl coenzyme-A reductase-1 (HMGR1) in A. paniculata. HMGR1 was constructed into the pBI121 expression vector controlled by the cauliflower mosaic virus (CaMV 35S) promoter. The pBI121-HMGR1 construct was transformed to A. paniculata through Agrobacteriummediated transformation followed by plant regeneration to obtain transgenic plants. Polymerase chain reaction (PCR) analysis was conducted to validate the transgenic plants, quantitative reverse transcription PCR (RT-qPCR) was used for the HMGR1 expression analysis, and high-performance liquid chromatography was employed to quantify the andrographolide content of the transgenic plants. PCR analysis on the transgenic plantlets indicated the presence of a 2,262 bp fragment that corresponded to HMGR1, thus confirming the integration of HMGR1 into the A. paniculata genome. The RT-qPCR results showed a 52.5-fold greater HMGR1 expression in the transgenic plant under the CaMV 35S promoter compared to the normal plant. As the expression level of HMGR1 increased, the amount of andrographolide was enhanced by up to 2.6 times in the transgenic plant compared to the control plant. This study demonstrates that the overexpression of HMGR1 driven by CaMV 35S can enhance the production of andrographolide in A. paniculata. [ABSTRACT FROM AUTHOR]

β-carotene is an important nutritional content in banana. However, its lifetime depends on the enzymes controlling its conversion into strigolactone. To understand the involved enzymes' activity, which are β-carotene isomerase (D27), carotenoid cleavage dioxygenase 7 (CCD7), and CCD8, would be the key to manipulate the rate of β-carotene degradation. In this research, the structure of genes and proteins of the D27, CCD7, and CCD8 from Musa acuminata were characterized. 'DH-Pahang' and Musa balbisiana 'Pisang Klutuk Wulung' (PKW). The corresponding sequence of genes from both species were aligned to determine similarity and intron/exon positions. Domains and motifs in the sequences of putative proteins of D27, CCD7, and CCD8 were also identified. It was found that D27, CCD7, and CCD8 genes in DH-Pahang and PKW comprise of various nucleotide sequence length, putative proteins, and numbers and length of exons and introns. However, the putative proteins possess the same domains: DUF4033 (domain of unknown function) in D27 and RPE65 (retinal pigment epithelium) in CCD7 and CCD8. Phylogenetic trees showed that D27, CCD7, and CCD8 proteins from DH-Pahang and PKW are conserved and clustered in the same clades with the same proteins of monocot plants. Hence, the results could be useful for future research in optimizing β-carotene content in banana. [ABSTRACT FROM AUTHOR]

Pisang tongkat langit (Musa troglodytarum L.) is a banana cultivar originated from Eastern Indonesia. Previous studies showed that ACS1 and ACO1 are genes that play an important role in banana ethylene biosynthesis. However, characterization and analysis of M. troglodytarum ACS1 and ACO1 genes have not been reported. This study aims to isolate and characterize the ACS1 and ACO1 gene expression profile during fruit ripening process. Gene fragment isolation was performed using PCR based method. Results showed that the isolated genomic fragments of ACS1 was 400 bp and ACO1 was 500 bp. cDNA fragments of ACS1 was 200 bp and ACO1 was 300 bp. Analysis of genomic fragments using BLAST NCBI showed that ACS1 had a high homology with 1818 bp ACS1 gene of Musa acuminata AAA Group (GenBank: GQ396304.1), while ACO1 gene had the highest homology with 1593 bp ACO1 gene of M. acuminata AAA Group (GenBank: AJ223232.1). ACS1 genomic fragments of M. troglodytarum had one intron and two exons, while ACO1 had two introns and three exons. Homology analysis showed that gene fragment of ACS1 and ACO1 of M. troglodytarum had conserved region similar to M. acuminata. [ABSTRACT FROM AUTHOR]

Fusarium wilt which is caused by the soil-borne fungus, Fusarium oxysporum f.sp. cubense (Foc), is one of important diseases in banana plant. Foc tropical race 4 (Foc TR4) is the most pathogenic race which could infect various banana cultivars including Cavendish cultivar which was previously considered as resistant cultivar. Molecular detection of Foc using PCR analysis is indispensable to determine the race of Foc. We demonstrate a faster DNA isolation procedure described in previous method by substituting sodium acetate precipitation with ammonium acetate precipitation without affecting the result. Based on our experience, some fungal genomes were troublesome to be amplified. We suggested pre-treatment step prior to amplification procedure by incubating fungal DNA in 65°C for 10 minutes for any samples of fungal genome, including stubborn samples, before mixing into PCR mix reagent. PCR reagents should be tested for stubborn samples since some of the reagents were unable to amplify the desired DNA fragment. Pre-treatment and the choice of robust PCR reagent should be taken into consideration for a reliable and consistent Foc TR4 molecular detection result. [ABSTRACT FROM AUTHOR]