Selection and Validation of Reference Genes for Normalization of RT-qPCR Analysis in Developing or Abiotic-Stressed Tissues of Loquat (Eriobotrya japonica)

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.

Molecular Cloning and Expression of Carotenogenic Genes in Yellowish and Mutant Whitish Loquat (Eriobotrya japonica) Fruits

ObjectiveThe study aimed to explore the factors regulating carotenoid accumulation in flesh color. MethodA loquat mutation （red-or orange-fleshed plant emerged a bud mutation of white-flesh in trunk） was used as material; HPLC analysis of β-carotene content was conducted. ResultThe β-carotene concentration in the flesh of wild and mutant types was 60.9 and 4.6 μg/g fresh weight, respectively. According to the conserved regions of genes from rose family genome, carotenogenic gene fragments in wild and mutant types were obtained. No nucleotide variation of the carotenogenic gene fragments was observed between wild and mutant genome. Real-time quantitative polymerase chain reaction （Q-PCR） was compared and one carotenogenic gene, β-ring hydroxylase （HYB） were considerably suppressed in mature mutant loquat fruits compared with that in wild. The other six carotenogenic genes were also expressed but the expression patterns appeared to be not correlated with the amount of β-carotene concentration in wild loquat flesh. ConclusionThe mutant whitish loquat lacks the ability to synthesize β-carotene because of the transcriptional down-regulation of carotenogenic gene HYB.

Occurrence, Prevention and Control of Cryphalus eriobotryae, a New Devastating Pest of Loquat

A devastating trunk beetle has been found in Baisha loquat in Dongshan Town, Wuzhong District, Suzhou City in recent years. It is iden-tified as a new insect species, Cryphalus eriobotryae, belonging to Scolytinae, Curculionidae, Coleoptera. So far, loquat is known as the unique host of C. eriobotryae, and trees of 20-30 years old or 3-4 years old are all attacked by the insect. Holes drilled by adults with the diameter of about0.8 mm and sores(ate by adults) with the diameter of 1 mm are found on bark and trunk of damaged trees. Three-dimensional channels in 3-4 layers are formed in cortex, which are filled with insect dung. The phloem turns black-brown in late stage, and loses transport function, resulting in plant death and a great impact on loquat production and industrial development. During the occurrence period of C. eriobotryae from April to November,the damaged trunks and branches should be sprayed with 48% chlorpyrifos EC or 5% imidacloprid EC 100 times dilution once every 10 d for con-tinuous 2-3 times, and various states of the insect could be killed. If the phloem is damaged in the early and middle stages and does not turn black and brown completely, the plant could grow new cortex to realize recovery.

Polyphenol Oxidase Inactivation by Microwave Oven and Its Effect on Phenolic Profile of Loquat (<i>Eriobotrya japonica</i>) Fruit

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.

Taxonomic Status of Daduhe Loquat （Eriobotrya prinoides var. dadunensis）

The taxonomic status of Daduhe loquat （E. prinoides var. dadunensis） was studied through analyzing genetic relationships among Oakleaf loquat （E. prinoides）, Daduhe loquat and Common loquat （E. japonica） using inter simple sequence repeats （ISSR） molecular marker and morphologic marker in this paper. Based on ISSR marker research, the similarity coefficient between Oakleaf loquat and Common loquat was lower than the similarity coefficient between Oakleaf loquat and Daduhe loquat while the similarity coefficient between Daduhe loquat and Common loquat was intermediate. The highest additivity was obtained when Daduhe loquat was regarded as the undetermined hybrid （45.8%）. The specific bands of Oakleaf loquat and Common loquat were present in Daduhe loquat. Based on morphologic traits research, Daduhe loquat was also between Oakleaf loquat and Common loquat but a little leaning to Oakleaf loquat. All the results support that Daduhe loquat was hybrid of Oakleaf loquat and Common loquat.

Seed Germination Traits of Loquat (Eriobotrya japonica Lindl.) as Affected by Various Pre-Sowing Treatments (Cutting of Cotyledons, Removal of Perisperm, Moist Chilling and/or Exogenous Application of Gibberellin)

The purpose of this study was to investigate the effects of various presowing treatments on the germinability(final germination percentage)and germination rate of loquat seeds in order to increase seedling production in nurseries(applied research)as well as provide answers for important physiological issues related to loquat seeds and their seed coat(basic research).Three experiments were carried out with various pre-sowing treatments.These treatments included full or partial removal of seed coat(perisperm),partial cutting of cotyledons as well as moist chilling at 5℃ for 13 days and/or soaking the seeds in water or 250 ppm gibberellic acid(GA_(3))solution for 24 h.According to the results,cotyledons excision resulted in delayed germination,regardless of the presence or absence of the seed coat in comparison with the decoated seeds that demonstrated the highest germination rate amongst them.In addition,even the partial excision of seed coats affected positively both the germinability and the germination rate,compared to the control-intact seeds.Furthermore,control-intact seeds had a higher germination percentage when exposed to moist chilling independently of the application or not of gibberellin;while the combination of gibberellin application and moist chilling improved both the percentage and the rate of germination of decoated seeds.In conclusion,the role of perisperm(seed coat)in the germination procedure of loquat seeds seems to be important,indicating the existence of seed coat-imposed dormancy on loquat seeds.Finally,the existence of a mild endogenous embryo-dormancy on loquat is also discussed.

Fingerprinting Patterns of SSR Markers Constructed for 33 Loquat[Eriobotrya japonica (Thunb. ) Lindl. ]Germplasms

[ Objective ] This study aimed to explore the ways of using SSR technology to construct the fingerprinting maps of the loquat. [ Method ] Fingerprinting patterns of the SSR markers for 33 loquat varieties in national loquat germplasm resource garden were constructed by specifically amplifying palymorphism from 7 pairs of primers screened from 51 pairs of primers of the relatives Mains and Pyrus. [ Result ] The results showed that the uses of 7 primers, namely, Hi01d05F, Hil2iO4F, CH02B10F, Hi03a03, Hi03e04, Hi04a05 and Hi02c07 could distinguish 33 loquat germplasms from one another completely. [ Conclusion] This study provides an essential criterion for classification and identification of the loquat resources.

双水相协同超声法提取枇杷叶中绿原酸的工艺研究

试验采用响应面法优化双水相协同超声法提取枇杷叶中绿原酸的工艺,探讨提取液中乙醇体积分数、超声温度、超声时间、磷酸氢二钾用量和超声功率对绿原酸提取率的影响。结果显示,双水相协同超声法提取枇杷叶中绿原酸最佳提取工艺条件为乙醇体积分数61%、超声温度61℃、超声时间25 min、磷酸氢二钾用量4.6 g,此条件下绿原酸提取率1.53%,与预测值相接近。研究表明,双水相协同超声法提取枇杷叶中绿原酸的提取工艺稳定可行,可为枇杷叶的资源化开发与利用提供参考。

贵州枇杷种质资源分布及其产业发展概述

贵州立体气候突出,野生枇杷种质资源丰富,性状差异性明显。目前已找到普通枇杷、大花枇杷、小叶枇杷3个种类,普通枇杷在全省广泛分布,大花枇杷主要分布在黔东南州雷公山一带,小叶枇杷主要分布在黔西南州兴义市一带。贵州省枇杷商品化栽培始于1958年,由黔东南州率先从江苏、浙江、福建等省引进优良品种进行试验示范。进入20世纪80年代中后期,贵阳市、黔南州、黔西南州等各地州(市)相继开展引种试验及小规模推广应用。截至2010年,在贵阳市、黔东南州、毕节市等地区拥有了万亩以上的规模化种植。特别是2015年以来,贵州各地枇杷种植生产发展速度迅猛,据2022年贵州省农业农村厅统计数据,全省枇杷种植面积已达2.3万hm^(2),年产量16.3万t,产值达17.1亿元,鲜果采摘期超过2个月。但栽培技术与管理水平仍较低,面积上升与产量增长不成正比,全省平均每666.7 m^(2)商品果产量不足500 kg,提升空间很大。存在问题主要为,一是缺乏地方规范的引、试、推制度体系,盲目性引种,造成品种混杂,良莠不齐,商品性低;二是对遗传优良性状的种质资源挖掘不足,缺乏地方特色的主导品种,市场竞争力不强;三是枇杷品牌创建与营销策略意识不强,形成行业内竞争压价销售,影响效益;四是鲜果产后冷链及深加工产品技术研发滞后,产业附加值增长有限;五是旱涝寒暑等极端天气频繁出现,山地果园设施栽培配套条件滞后,抗风险能力不强等。主要围绕贵州枇杷种质资源分布特征、引种与育种、栽培技术演变、产业发展及其制约因子等方面进行了分析,尝试提出贵州枇杷产业当前与未来的主要任务,以推动枇杷产业高质量发展。

基于MobileViT-CBAM的枇杷表面缺陷检测方法

为实现枇杷采后快速、准确筛选,本文以MobileViT为主干特征提取网络,通过分别在Layer1和Layer2层之后嵌入注意力模块CBAM(Convolutional block attention module),强化网络在通道和空间上对细节特征的提取能力,构建了一种轻量化网络模型MobileViT-CBAM。相较于MobileViT,在验证集和测试集上本文方法对疤痕、机械伤、腐烂等缺陷果的识别准确率分别提高1.17、1.23个百分点。试验结果表明,MobileViT-CBAM模型与VGG16、ResNet34、MobileNetV2相比较,准确率最高(97.86%),同时兼具内存占用量小(3.768 MB)、推理时间短(每幅图像需42 ms)的优势。该轻量化网络模型可部署于嵌入式系统。本研究为构建枇杷在线检测系统提供了缺陷识别理论基础,为枇杷等农产品外部品质检测提供了一个高效、准确的方法。

优质大果中熟白肉枇杷新品种中白的选育

中白是从早钟6号×贵妃杂交群体中选育的优质大果中熟白肉枇杷新品种。该品种树势中庸偏强,树冠圆头形,中心干较明显,枝梢较强壮。平均单果质量60.1 g,大小整齐;果实倒卵圆形,果基钝圆少数尖峭,果顶钝圆微凹;果皮橙黄色,厚度中等偏薄,锈斑少,果点密度中等,果点中等大;萼片平展,萼孔闭合;果肉黄白色,平均厚度10.9 mm,肉质细嫩、化渣、汁多;平均可溶性固形物含量(w)13.4%,味鲜、风味浓郁,品质优;平均可食率71.2%,平均种子4.6粒·果^(-1);在福建福州地区,果实4月中下旬成熟。高接换种后第2年可少量开花,第3年枝梢抽穗率50%左右,第4年株产22.8 kg,折合666.7 m^(2)产709.7 kg,早结、丰产、稳产。中白是一个优质、大果、丰产稳产、抗性较强的中熟白肉枇杷新品种,适宜在福建、四川、重庆、云南等枇杷产区应用。

“贵妃”枇杷高产高效栽培技术

“贵妃”枇杷是福建省农业科学院果树研究所通过实生选种选育出的白肉枇杷新品种,2014年6月30日通过全国热带作物品种审定委员会审定。近年来在福建、四川、重庆、广东等地引种示范,取得了良好效果。为了更好地促进福建枇杷品种结构调整、品质提升和枇杷产业的可持续发展,本文从肥水管理、生草栽培、树体管理、花果管理和病虫害防治等方面介绍了“贵妃”枇杷高产高效栽培技术。

不同采收期枇杷叶中氨基酸的组成与分析

目的 对12个月份采收期枇杷叶的氨基酸成分组成及含量变化进行分析,为确定枇杷叶采收期及资源利用提供理论依据。方法 采用异硫氰酸苯酯柱前衍生化高效液相色谱法测定不同月份枇杷叶氨基酸组成及含量;采用SPSS22.0版软件进行数据统计学差异及相关性分析;根据世界卫生组织(WHO)和联合国粮农组织(FAO)提出的理想模式及朱圣陶提出的氨基酸比值系数法,对不同采收期的枇杷叶氨基酸进行评分。结果 不同采收期枇杷叶中均含有17种氨基酸,7种人体必需氨基酸(EAA)、9种儿童必需氨基酸(CEAA)及9种药用氨基酸。17种氨基酸分别是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、组氨酸、精氨酸、苏氨酸、丙氨酸、脯氨酸、酪氨酸、缬氨酸、甲硫氨酸、胱氨酸、异亮氨酸、亮氨酸、苯丙氨酸、赖氨酸,它们的平均含量分别为3.41~7.23、4.64~9.66、2.05~3.75、2.99~4.95、0.01~1.56、2.33~4.85、2.10~4.03、2.67~5.48、5.37~7.64、1.45~3.49、2.70~5.53、0.01~0.48、3.64~4.78、1.91~4.15、3.96~7.83、2.39~4.60、1.85~3.65 mg·g^(-1)。不同采收期枇杷叶中17种氨基酸、总氨基酸(TFAA)、EAA总量、CEAA总量、药用氨基酸、苦味氨基酸的含量间差异有统计学意义(P<0.05);苦味氨基酸在总氨基酸中的百分含量较稳定。不同采收期枇杷叶的EAA含量为44.26%~50.33%,明显高于WHO/FAO模式值(35.00%);EAA/非必需氨基酸(NEAA)均值(55.67%)和EAA/TFAA均值(35.74%)分别接近WHO/FAO模式值的60%、40%;不同采收期枇杷叶的17种氨基酸含量峰值前2位是7月和11月;氨基酸比值系数分(SRC)值为62.53~76.17,前3位为11月、8月及7月。赖氨酸为枇杷叶的第一限制氨基酸。苦味氨基酸与药用氨基酸、TFAA呈正相关(P<0.01)。结论 枇杷叶中氨基酸种类齐全,组成合理,具有较佳开发利用价值;不同月份氨基酸的含量差异大,7月和11月是枇杷叶氨基酸合理开发利用的较佳时期。

枇杷中氟吡菌酰胺、肟菌酯及代谢产物残留分析与膳食风险评估

为明确氟吡菌酰胺和肟菌酯在枇杷上的残留与膳食风险,采用超高效液相色谱-串联质谱仪(ultra-performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测了枇杷中氟吡菌酰胺及其代谢物2-(三氟甲基)苯甲酰胺和肟菌酯及其代谢物肟菌酸在果实生长过程中的消解动态和残留量,并进行了膳食风险评估。样品采用乙腈提取,氨基固相萃取柱净化,UPLC-MS/MS检测。结果表明,在0.01~1.00 mg/kg添加水平下,回收率为82%~93%,相对标准偏差为1.4%~2.8%,定量限均为0.01 mg/kg,方法灵敏度及准确度良好,能够满足枇杷中农药残留检测要求。按照良好农业规范要求,在枇杷上施用43%氟吡菌酰胺·肟菌酯悬浮剂,当剂量为333 mg/kg、施药2次,施药间隔10~15 d,距末次施药后28、35 d时,枇杷中氟吡菌酰胺残留量为<0.01~0.03 mg/kg、消解率>90%;肟菌酯的残留量为<0.02~0.04 mg/kg、消解率>85%,肟菌酯的残留量低于我国规定的最大残留限量0.7 mg/kg。膳食风险评估表明,按照推荐剂量使用,枇杷中氟吡菌酰胺残留水平对一般人群健康不会产生不可接受的风险。研究结果可为氟吡菌酰胺和肟菌酯在枇杷树上的科学合理使用提供数据和技术支撑。

西藏墨脱地区枇杷新拟盘多毛孢菌培养特征及致病力分析

【目的】为探究来自西藏墨脱地区枇杷叶斑病新拟盘多毛孢菌的生物学特性,有效预防病害的发生。【方法】采用平板培养法和离体叶片接种法对病原菌进行培养和致病力测定。【结果】供试21个菌株在PDA培养基上培养12 d,依据培养基中着生的分生孢子盘数量的高、中和低,将菌落培养表型划分为Ⅰ型、Ⅱ型和Ⅲ型,菌株出现频率分别为38.10%、33.33%和28.57%。培养5 d,菌落生长速率范围值为12.68~15.60 mm/d,平均值为14.33 mm/d。培养12 d,菌落产孢量高于和低于1×10^(5)个孢子/cm^(2)的菌株出现频率分别为71.43%和28.57%,有致病力和无致病力的菌株出现频率分别为61.90%和38.10%。菌株致病力与菌落生长速率以及产孢量之间均无相关性。【结论】西藏墨脱地区流行的新拟盘多毛孢菌培养特征及致病力出现明显分化,大部分菌株产孢能力强,且对枇杷有致病力。

低温胁迫对枇杷生理特性及抗寒相关基因差异表达的影响

研究低温胁迫下2个枇杷幼果种胚生理指标变化及抗寒相关EjICE1基因的表达规律,为枇杷抗寒新材料的筛选及枇杷抗寒分子机理的解析提供理论依据。以洞庭枇杷(黄肉,DT)及洞庭枇杷突变型(白肉,DTM)挂果容器苗为材料,研究人工模拟低温对枇杷相对电导率(REC)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性及EjICE1基因的表达规律的影响。结果表明,低温胁迫下2个枇杷幼果种胚相对电导率REC均呈“S”型曲线变化,Logistic方程显示,洞庭枇杷和突变型(DTM)半致死温度LT50分别为-4.759、-2.811℃,突变型(白肉,DTM)幼果的抗寒能力强于洞庭枇杷;2个枇杷的SOD、POD及CAT活性及洞庭枇杷(DT)的MDA含量均呈现出先升后降的变化趋势,但达到最大阈值的时间点不同,而突变型(DTM)MDA含量则呈现缓慢上升趋势,洞庭枇杷SOD在1℃达到最大阈值,丙二醛(MDA)含量、POD及CAT活性在-1℃达到最大阈值;突变型(DTM)SOD、POD及CAT活性在-3℃达到最大阈值,丙二醛(MDA)含量则在-5℃达到最大阈值。EjICE1基因在2个枇杷中的表达呈先升后降的趋势,突变型(DTM)EjICE1基因的表达水平均高于同时期的洞庭枇杷,最大表达量出现在-3℃,洞庭枇杷EjICE1基因最大表达量出现在-1℃,在-5℃时2个枇杷中EjICE1基因的表达均被强烈抑制。突变型(DTM)幼果的抗寒能力强于亲本洞庭枇杷(DT),低温胁迫下,突变型(DTM)具有较高的保护酶活性,能快速激活抗寒相关基因的表达,启动低温应答机制,进而抵御和适应低温伤害。

枇杷叶三萜酸联合重组人表皮生长因子对激素依赖性皮炎豚鼠皮肤屏障功能的修复及免疫失衡的影响

目的 观察枇杷叶三萜酸(TAL)联合重组人表皮生长因子(rh-EGF)对激素依赖性皮炎(HDD)豚鼠模型皮肤屏障功能修复及免疫失衡的影响。方法 选取40只无特定病原(SPF)级豚鼠,随机分为对照组、模型组、rh-EGF组、TAL组和联合组,每组各8只。除对照组外,其他各组涂抹0.05%卤米松乳膏,连续45 d,构建HDD模型。构建成功后,rh-EGF组涂抹rh-EGF凝胶,TAL组涂抹TAL溶液,联合组涂抹TAL和rh-EGF凝胶,对照组和模型组涂抹生理盐水,共15 d。记录各组临床症状并打分;检测经皮水分丢失(TEWL)、角质层含水量(WCSC)和皮脂量(SC);HE染色观察各组豚鼠皮肤组织病理变化;采用酶联免疫吸附测定(ELISA)法检测总免疫球蛋白E(IgE)、白细胞介素-4(IL-4)、干扰素-γ(IFN-γ)水平。结果 与对照组比较,模型组症状明显、皮肤组织损坏严重,TEWL增加,WCSC和SC减少;免疫因子Ig E和IL-4水平升高、IFN-γ水平降低(P<0.05)。与模型组比较,rh-EGF组、TAL组和联合组用药后临床症状减轻、皮肤组织损伤不明显;TEWL减少,WCSC和SC增加,免疫因子IgE和IL-4水平降低、IFN-γ水平升高(P<0.05)。且联合组与rh-EGF组和TAL组比较,作用效果更加明显(P<0.05)。TAL组和联合组各指标比较,差异无统计学意义(P>0.05)。结论 TAL联合rh-EGF可有效缓解HDD豚鼠的临床症状,改善皮肤细胞损伤,修复皮肤屏障功能,提升免疫能力。

枇杷叶提取物对高糖饮食诱导的黑腹果蝇代谢紊乱的缓解作用

为了探究枇杷叶提取物对高糖饮食诱导的代谢紊乱的缓解作用,以黑腹果蝇为研究对象,设置基础培养基、高糖培养基和分别添加1%、5%、10%枇杷叶提取物的含药培养基对黑腹果蝇进行培养,对各组黑腹果蝇的寿命、运动能力、生长发育指标、抗氧化能力、肠道完整性、肠道微生物多样性进行检测。结果表明,高糖饮食能造成黑腹果蝇代谢紊乱,在饮食中添加10%的枇杷叶提取物能通过延长黑腹果蝇寿命、提高老年黑腹果蝇的运动能力、提高黑腹果蝇卵的蛹化率和羽化率来提高黑腹果蝇的生长性能;通过提高黑腹果蝇体内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性,降低脂质过氧化物丙二醛(MDA)含量来提高黑腹果蝇的抗氧化能力;通过肠道菌群16S rRNA测序和分析发现,高糖饮食能导致黑腹果蝇肠道菌群失调,在饮食中添加10%枇杷叶提取物能通过提高菌群丰度、抑制肠炎相关菌群增殖、改变菌群组成等方式缓解菌群失调。结果显示,枇杷叶提取物可在一定程度上缓解高糖饮食造成的代谢紊乱。

灵芝菌发酵枇杷叶茶的研制

以枇杷叶为主料,研究利用灵芝菌来发酵枇杷叶制成养生茶,并测定其营养成分与重金属、农残含量。结果表明:美芝、大红芝可作为发酵枇杷叶的灵芝菌株;美芝菌丝生长速度较大红芝的快,生长速度配方B>配方C>配方A;添加少量的玉米粉、甜叶菊能够促进灵芝菌丝的生长,添加少量的甜叶菊有助于提升发酵茶的口感;发酵后的枇杷叶中多糖、总蛋白、游离氨基酸含量均有显著增加,但三萜酸含量有所下降;不同灵芝菌株发酵后的枇杷叶营养成分有所差别;发酵后的枇杷叶的重金属、农残含量均符合检测标准。

Effects of Peracetic Acid(PAA) Combined with Calcium Treatments on Storage Quality of Loquat Fruit

[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 .