PISTILLATA (PI)-like genes are crucial regulators of flowering in angiosperms. A homologue of PI, designated as AcPI (Genbank accession number HQ717796), was isolated from pineapple cultivar Comte de Paris by reverse transcriptase polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The cDNA sequence of AcPI is 907 bp in length and contains an open reading frame of 594 bp, which encodes a protein of 197 amino acids. The molecular weight was 2.29 kDa and the isoelectric point was 9.28. The alignment showed that AcPI had a high identity with CsPIC2 (78.6%), AoPI (77.4%), OrcPI (75.7%) and HPI2 (72.4%). Quantitative real-time polymerase chain reaction (qRT-PCR) analyses in different tissues showed that the expression pattern of AcPI was different from the B-class genes in eudicots. AcPI was expressed in all the tissues investigated. The expression level was very low in fruit stems, bracts, leaves and sepals, high in petals and carpels, and moderate in apical meristems, flesh and stamens. The qRT-PCR analyses in different stages indicated that the expression of AcPI reached the highest level at 40 days after flower inducement, when the multiple fruit and floral organs were forming. It proved the important role of AcPI in floral organs and fruit development. The 35S::AcPI transgenic Arabidopsis plants flowered earlier and had more inflorescences or branches than wild type plants.

Hyperlipidemia, characterized by an abnormal lipid metabolism, is related to multiple cardiovascular diseases that pose challenges to global public health. Macadamia oil (MO), rich in monounsaturated fatty acids (around 80%), is regarded as a functional oil used to regulate lipid accumulation. Nonetheless, the lipid-lowering mechanism of MO is still unknown. Therefore, the lipid-lowering effects of MO in high-fat diet (HFD)-induced hyperlipidemic mice were evaluated in this study. The results revealed that MO could effectively reduce body weight and the organ index and improve serum lipid levels by reducing total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels and elevating high-density lipoprotein cholesterol levels. Additionally, MO supplementation could improve abnormal liver function caused by hyperlipemia, characterized by decreased liver enzyme levels, including alanine aminotransferase and aspartate aminotransferase. Meanwhile, MO also exhibited an inhibitory effect on oxidative stress and lipid accumulation caused by an HFD. Moreover, findings from qRT-PCR and Western blotting analyses suggest that MO supplementation markedly prevented hyperlipidemia by inhibiting the expression of AMPK pathway-related genes, SREBP-1c, FAS, ACC, and PPAR-γ, as well as upregulating the levels of Nrf2, HO-1, and γ-GCS. These results indicate that MO attenuates lipid accumulation in vivo via AMPK/Nrf2 pathway activation, suggesting that MO could serve as a dietary supplementation or medication for treating hyperlipidemia.

Amomum villosum Lour. (A. villosum), known as Sharen in China, is widely used for culinary and medicinal purposes due to containing a diverse set of bioactive compounds. In this study, the optimum ethanol extraction process was optimized and the composition and biological activities (antioxidant and antitumor) of five different fractions (dichloromethane, petroleum ether, ethyl acetate, n-butanol and H₂O) extracted from the ethanol extract of A. villosum were investigated. The results showed that the optimal extraction conditions were extraction temperature 80°C, extraction time 120 min, ethanol concentration 40% and solid–liquid ratio 1:25 g/mL. Moreover, 35 bioactive compounds were successfully identified by UPLC-ESI-QTOF-MS/MS from five factions for the first time, including 12 phenolic acids and derivatives, 2 organic acids, 12 flavonoids and derivatives, 2 oxylipins and 7 proanthocyanidins. Among them, ethyl acetate fraction (Fr-EtOAc) exhibited the highest content of total phenolic (374.01 mg GAE/g DW) and flavonoid (93.11 mg RE/g DW), where vanillic acid, catechin, epicatechin and protocatechuic acid were the predominant phenolic compounds that accounting for 81.65% of the quantified bioactive compounds. In addition, Fr-EtOAc demonstrated excellent total antioxidant activity (IC₅₀ of DPPH and ABTS assays were 0.23, 0.08 mg/mL, respectively, and FRAP assay was 322.91 mg VCE/100 g DW) and antitumor activity (1,000 μg/mL, 79.04% inhibition rate). The results could provide guidance for the industrial production and application of A. villosum.

Tropical rainforest soils, or latosols, are distinguished by their low pH and low fertility. In orchards, co-cultivating grass has become popular as a way to improve soil quality and boost fruit production. Nevertheless, insufficient information is currently available about the response of soil microbial communities in tropical rainforest orchards to grass co-cultivation. Therefore, the present research investigates the effect of grass cultivation on the soil properties and microbial diversity of guava (Psidium guajava L. cv Pearl) latosol orchards. Two varieties of the tropical legume grass Stylosanthes guianensis, i.e., Reyan No. 2 and Ubon, were studied, besides the control (CK), which is without any grass, and the natural grasses treatment (N). The study contained four treatments, i.e., S. guianensis cv. Reyan No. 2, S. guianensis cv. Ubon, CK, and N. Soil samples from the top layer (0–20 cm) and subsoil layer (20–40 cm) were collected to follow the changes in soil microbial biodiversity based on 16 S rDNA analysis. A total of 17,231 kinds of OTUs (Operational Taxonomic Units) were obtained, including 17,165 kinds of bacteria and 66 kinds of Archaea. S. guianensis cv. The Ubon variety, natural grasses, and CK treatments significantly increased the soil microbial richness and evenness in the topsoil layer compared to Reyan No. 2 variety. The β-diversity of soil microbial community was significantly reduced in the natural grasses and Ubon variety treatments at the topsoil layer compared to CK treatment. In the subsoil layer, natural grasses, Reyan No. 2, and Ubon treatments significantly increased the soil microbial community based on β-diversity. The presence of natural grasses caused 49% and 42% increases in the SOC in the top and subsoil layers, respectively, as well as remarkable increases in the available and total soil nitrogen. The grass intercropping enhanced the levels of soil carbon and nitrogen and altered the nature of the soil’s microbial community. The diversity of soil microorganisms in the subsoil layer is significantly altered by the shallow root systems of tropical legume and natural grasses, which have most of their roots concentrated in the top soil layer. Overall, growing grass in tropical orchards benefits the latosolic soil microorganisms, which has enhanced the theoretical underpinnings for using grass to improve the soil quality in latosols orchards.