The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic ext...The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic extracts prepared from fresh, and microwave-treated samples were analyzed. Antioxidant activity was also evaluated by 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH+) methods. In addition, polyphenol oxidase inactivation was carried out using a response surface methodology to establish the optimal conditions of treatment. The phenolic content of fresh mesocarp was 311 ± 0.60 mg gallic acid equivalents (GAE)/100g dry weight (DW) and that of microwave-treated mesocarp was 1230 ± 0.36 mg GAE/100g DW. Total phenolic content of water/ methanol extract significantly increases after microwave treatment rather than methanolic extract of fresh loquat. Five glycoside phenolics were identified by HPLC-DAD-MS as 3-caffeoylquinic acid, 3-p-coumaroylquinic acid, 5-caffeoylquinic acid and quercetin-3-O-sambubioside. Methanolic extract of microwave-treated mesocarp showed higher antioxidant activity than that of fresh mesocarp. Thus, polyphenol oxidase inactivation by microwave energy preserved the integrity of phenolic compounds as well as antioxidant activity in mesocarp extracts prepared from loquat fruit. It was also noted that phenolics were more abundant in the microwaved samples than in the fresh samples.展开更多
Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-...Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments.展开更多
[Objective] The study aimed to investigate the Ioquat leaf mould disease in Mengzi City of Yunnan Province and lay the foundation for determination of effective prevention and control methods.[Method] Loquat leaf moul...[Objective] The study aimed to investigate the Ioquat leaf mould disease in Mengzi City of Yunnan Province and lay the foundation for determination of effective prevention and control methods.[Method] Loquat leaf mould pathogenic fungus was isolated by tissue separation method and inoculated with conidial suspension.The pathogenicity of Ioquat leaf mould pathogen was verified by Koch＇s postulate.Under a microscope,mycelial morphology and conidial fructification were observed,spore sizes were measured,and Ioquat leaf mould pathogen was identified according to the morphological characteristics.[Result] Velvet-like,olive green fungal colonies were generated on PDA medium.Conidiophores erect,apex curved,dark brown,smooth,with obvious spore marks and no diaphragm,（33.0-152.8） μm×（2.6-4.0）μm.Cladosporium was brown or pale olive with spore marks,monocelled or with one diaphragm,（7.1-19.0） μm × （1.9-5.9） μm.Conidia concatenate （2-4）,oval or spherical,with no spore mark,light olive,monocelled,smooth,（2.1-9.4） μm × （1.2-2.6） μm.[Conclusion] Loquat leaf mold disease began to occur in the germination period of spring shoots and summer shoots and became serious in the germination period of autumn shoots.Sooty mold-like layer grew on both front and back surfaces and densely covered the whole leaves,thus seriously affecting the photosynthesis of plants.The pathogen was preliminarily identified as Cladosporium eriobotryae Pass.＆ Beltrani.展开更多
[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharves...[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .展开更多
To investigate chemical constituents of Eriobotrya japonica(Thunb.) Lindl.leaf,six compounds were isolated by combination of RP-18,silica gel and Sephadex LH-20 column chromatographies,and their structures were identi...To investigate chemical constituents of Eriobotrya japonica(Thunb.) Lindl.leaf,six compounds were isolated by combination of RP-18,silica gel and Sephadex LH-20 column chromatographies,and their structures were identified by chemical and spectral methods.They were identified as tricosanoic acid(Ⅰ),phenylpropyl acid(Ⅱ),rutin(Ⅲ),2β,3β,19α-trihydroxyurs-12-en-28-oic acid(Ⅳ),2α,3α,19α-trihydroxyurs-12-en-28-oic acid(Ⅴ),Nerolidol-3-O-α-L-rhamnopyranosyl(1→4)-α-L-rhamnopyranosyl(1→2)-[α-L-rhamnopyranosyl(1→6)]-β-D-glucopyranoside(Ⅵ).Compound Ⅰ,Ⅱ and Ⅳ were isolated from this plant for the first time.展开更多
文摘The objective of this research was investigated the effect of polyphenol oxidase microwave treatment on phenolic composition, antioxidant activity and microstructure of loquat fruit. Phenolic profile of methanolic extracts prepared from fresh, and microwave-treated samples were analyzed. Antioxidant activity was also evaluated by 2,2’-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH+) methods. In addition, polyphenol oxidase inactivation was carried out using a response surface methodology to establish the optimal conditions of treatment. The phenolic content of fresh mesocarp was 311 ± 0.60 mg gallic acid equivalents (GAE)/100g dry weight (DW) and that of microwave-treated mesocarp was 1230 ± 0.36 mg GAE/100g DW. Total phenolic content of water/ methanol extract significantly increases after microwave treatment rather than methanolic extract of fresh loquat. Five glycoside phenolics were identified by HPLC-DAD-MS as 3-caffeoylquinic acid, 3-p-coumaroylquinic acid, 5-caffeoylquinic acid and quercetin-3-O-sambubioside. Methanolic extract of microwave-treated mesocarp showed higher antioxidant activity than that of fresh mesocarp. Thus, polyphenol oxidase inactivation by microwave energy preserved the integrity of phenolic compounds as well as antioxidant activity in mesocarp extracts prepared from loquat fruit. It was also noted that phenolics were more abundant in the microwaved samples than in the fresh samples.
基金funded by the Natural Science Foundation of Fujian Province(2021J05240)Fujian Provincial Science and Technology Project(2021N5014,2022N5006)+1 种基金Research Project of Putian Science and Technology Bureau(2021ZP08,2021ZP09,2021ZP10,2021ZP11)Scientific Research Project of Putian University(2018064).
文摘Loquat(Eriobotrya japonica Lindl.)is a subtropical evergreen fruit tree that produces fruits with abundant nutrients and medicinal components.Confirming suitable reference genes for a set of loquat samples before qRT-PCR experiments is essential for the accurate quantification of gene expression.In this study,eight candidate reference genes were selected from our previously published RNA-seq data,and primers for each candidate reference gene were designed and evaluated.The Cq values of the candidate reference genes were calculated by RT-qPCR in 31 different loquat samples,including 12 subgroups of developing or abiotic-stressed tissues.Different combinations of stable reference genes were screened according to a comprehensive rank,which was synthesized from the results of four algorithms,including the geNorm,NormFinder,BestKeeper andΔCt methods.The screened reference genes were verified by normalizing EjLGA1 in each subgroup.The obtained suitable combinations of reference genes for accurate normalization were GAPDH,EF1αand ACT for floral development;GAPDH,UBCE and ACT for fruit setting;EF1α,GAPDH and eIF2B for fruit ripening;ACT,EF1αand UBCE for leaves under heat stress;eIF2B,UBCE and EF1αfor leaves under freezing stress;EF1α,TUA and UBCE for leaves under salt stress;ACT,EF1αand eIF2B for immature pulp under freezing stress;ACT,UBCE and eIF2B for immature seeds under freezing stress;EF1α,eIF2B and UBCE for both immature pulp and seeds under freezing stress;UBCE,TUB and TUA for red-fleshed fruits under cold-storage stress;eIF2B,RPS3 and TUB for white-fleshed fruits under coldstorage stress;and eIF2B,UBCE and RPS3 for both red-and white-fleshed fruits under cold-storage stress.This study obtained different combinations of stable reference genes for accurate normalization in twelve subgroups of developing or abiotic-stressed tissues in loquat.To our knowledge,this is the first report to obtain stable reference genes for normalizing gene expression of abiotic-stressed tissues in E.japonica.The use of the three most stable reference genes could increase the reliability of future quantification experiments.
文摘[Objective] The study aimed to investigate the Ioquat leaf mould disease in Mengzi City of Yunnan Province and lay the foundation for determination of effective prevention and control methods.[Method] Loquat leaf mould pathogenic fungus was isolated by tissue separation method and inoculated with conidial suspension.The pathogenicity of Ioquat leaf mould pathogen was verified by Koch＇s postulate.Under a microscope,mycelial morphology and conidial fructification were observed,spore sizes were measured,and Ioquat leaf mould pathogen was identified according to the morphological characteristics.[Result] Velvet-like,olive green fungal colonies were generated on PDA medium.Conidiophores erect,apex curved,dark brown,smooth,with obvious spore marks and no diaphragm,（33.0-152.8） μm×（2.6-4.0）μm.Cladosporium was brown or pale olive with spore marks,monocelled or with one diaphragm,（7.1-19.0） μm × （1.9-5.9） μm.Conidia concatenate （2-4）,oval or spherical,with no spore mark,light olive,monocelled,smooth,（2.1-9.4） μm × （1.2-2.6） μm.[Conclusion] Loquat leaf mold disease began to occur in the germination period of spring shoots and summer shoots and became serious in the germination period of autumn shoots.Sooty mold-like layer grew on both front and back surfaces and densely covered the whole leaves,thus seriously affecting the photosynthesis of plants.The pathogen was preliminarily identified as Cladosporium eriobotryae Pass.＆ Beltrani.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest "Tec-hnology Research and Experimental Demonstration of Loquat Industry"(201003073)~~
文摘[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .
文摘To investigate chemical constituents of Eriobotrya japonica(Thunb.) Lindl.leaf,six compounds were isolated by combination of RP-18,silica gel and Sephadex LH-20 column chromatographies,and their structures were identified by chemical and spectral methods.They were identified as tricosanoic acid(Ⅰ),phenylpropyl acid(Ⅱ),rutin(Ⅲ),2β,3β,19α-trihydroxyurs-12-en-28-oic acid(Ⅳ),2α,3α,19α-trihydroxyurs-12-en-28-oic acid(Ⅴ),Nerolidol-3-O-α-L-rhamnopyranosyl(1→4)-α-L-rhamnopyranosyl(1→2)-[α-L-rhamnopyranosyl(1→6)]-β-D-glucopyranoside(Ⅵ).Compound Ⅰ,Ⅱ and Ⅳ were isolated from this plant for the first time.
